Review Article | Vol. 6, Issue 1 | Journal of Neuro and Oncology Research | Open Access |
Eduardo Augusto Iunes1
, Christian Luiz Baptista Gerbelli2 , Jean Eduardo de Sousa Carvalho Dezena2 , Telmo Augusto Barba Belsuzarri3 , Tiago Kiyoshi Kitabayashi Braga2 , Fabio Veiga de Castro Sparapani1, Sérgio Cavalheiro1, Franz Jooji Onishi1*
1Department of Neurosurgery, Federal University of São Paulo (Unifesp), São Paulo, Brazil
2Division of Neurosurgery, Department of Surgery and Anatomy, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
3Department of Neurosurgery, Pontifical Catholic University of Campinas (PUC-Campinas), Campinas, São Paulo, Brazil
*Correspondence author: Franz Jooji Onishi, Department of Neurosurgery, Federal University of São Paulo (Unifesp), São Paulo, Brazil;
Email: onishi@huhsp.org.br
Citation: Iunes EA, et al. Sacral Melanotic Schwannoma: A Systematic Review of the Literature. J Neuro Onco Res. 2026;6(1):1-22.
Copyright: © 2026 The Authors. Published by Athenaeum Scientific Publishers.
This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
License URL: https://creativecommons.org/licenses/by/4.0/
| Received 28 January, 2026 | Accepted 16 February, 2026 | Published 23 February, 2026 |
Background: Melanotic schwannoma (MS) is a rare variant of nerve sheath tumor, accounting for less than 1% of all primary schwannomas. Although historically considered benign, MS has demonstrated unpredictable behavior.
Methodology: A comprehensive search was performed in the PubMed and Embase databases to identify relevant case reports and case series on spinal melanotic schwannoma. Study selection was based on predefined inclusion criteria. The methodological quality and risk of bias of the included reports were assessed using the Joanna Briggs Institute (JBI) Critical Appraisal Checklist for Case Reports.
Results: Our review identified 70 articles describing a total of 118 patients with spinal melanotic schwannoma. MS primarily affects adult individuals, with no apparent sex predilection. The lumbosacral region was the most commonly affected spinal segment. Gross total resection was the preferred treatment in the majority of cases. Adjuvant therapies were inconsistently applied. Recurrence occurred in a significant proportion of patients and mortality was reported despite aggressive treatment in some cases.
Conclusion: Melanotic schwannoma of the spine is a rare tumor with potentially more aggressive behavior than previously thought. Gross total resection remains the mainstay of treatment.
Keywords: Melanotic Schwannoma; Spinal Schwannoma; Intradural Extramedullary Tumor; Spinal Neoplasms; Sacral Tumors; Nerve Sheath Tumors; Malignant Peripheral Nerve Sheath Tumor
Melanotic Schwannoma (MS) is a rare variant of nerve sheath tumor composed of melanin-producing neoplastic Schwann cells. First described by Millar in 1932, MS accounts for less than 1% of all primary schwannomas [1-3]. Unlike conventional schwannomas, its biological behavior remains incompletely understood. A subset of MS cases occurs in association with Carney complex, a rare autosomal dominant syndrome characterized by cutaneous pigmentation, cardiac and extracardiac myxomas, endocrine tumors and psammomatous melanotic schwannomas. This association was first described by Carney in 1990 [4].
Approximately 200 cases of malignant schwannoma have been reported to date. These tumors most often arise from spinal nerve roots, particularly in the lumbosacral and thoracic regions, with rarer involvement of the sympathetic chain, cranial nerves, peripheral nerves and the gastrointestinal tract. Clinical presentation typically consists of localized pain related to tumor location [2,5,6].
Historically considered benign, MS is now recognized to have unpredictable and potentially aggressive behavior, with several reports documenting local recurrence, distant metastasis and even disease-related mortality [7,8].
There is currently no standardized treatment protocol for MS. Most authors recommend Gross Total Resection (GTR) as the primary treatment, aiming to reduce the risk of recurrence or progression [1,8-14]. The role of adjuvant therapy remains controversial, with some centers offering radiotherapy or chemotherapy in selected cases, particularly when complete resection is not achieved or in cases of recurrence.
In this review, we present an illustrative case of sacral melanotic schwannoma in a young woman, managed with surgical resection and adjuvant radiotherapy, followed by over four years of recurrence-free follow-up. In addition, we conducted a systematic review of the literature to summarize the clinical features, treatment strategies and outcomes of spinal MS, aiming to contribute to a better understanding of this rare entity.
Melanotic schwannomas are rare nerve sheath tumors with more aggressive behavior than conventional schwannomas. Although diagnosis is challenging, characteristic MRI features such as T1 hyperintensity and early enhancement can help differentiate them. This study provides the most comprehensive review to date, highlighting key clinical, radiological and pathological findings.
Systematic Review
This systematic review followed PRISMA guidelines. We included original reports of spinal melanotic schwannoma with histopathological confirmation, encompassing case reports, case series and cohort studies. Review articles, letters, conference abstracts without data and animal studies were excluded.
A comprehensive search of PubMed and Embase was performed up to June 2024, with no language or date restrictions. Reference lists were also screened manually. Two reviewers independently selected studies, extracted data and resolved disagreements by consensus.
Extracted variables included demographics, tumor characteristics, treatment, neurological outcomes, recurrence and follow-up duration. Study quality was assessed using the Joanna Briggs Institute checklist, with all included cases scoring 7-8. Due to heterogeneity, a narrative synthesis was performed rather than a meta-analysis.
Illustrative Case
History and Presentation
A 21-year-old woman presented with a two-year history of low back pain radiating to the left lower limb, corresponding to the S1 dermatome. She had no relevant family history or clinical signs suggestive of Carney complex. Electromyoneurography demonstrated mild radiculopathy involving the left S1 nerve root.
Initial Magnetic Resonance Imaging (MRI) revealed a nodular intradural extramedullary lesion located at the left S1 foramen, with associated remodeling of the adjacent sacral bone and evidence of necrotic and hemorrhagic components. The lesion appeared isointense on T1-weighted sequences and hypointense on T2-weighted sequences (Fig. 1-4). These imaging features were consistent with a peripheral nerve sheath tumor. Despite minimal clinical symptoms, subsequent MRI demonstrated progressive growth of the lesion, reaching dimensions of 3.5 × 3.3 × 1.8 cm. Given the documented enlargement, surgical intervention was indicated (Fig. S1).
Figure 1: Sagittal T1, T2 and STIR-weighted (A, B and C) images showing the tumor located at S1, measuring 3.5 x 3.3 x 1.8 cm.
Figure 2: Axial T1 (A), T2 (B) and axial and sagittal T1-fat suppression postcontrast (C and D) weighted image disclosing an oval lesion with hypersignal T1.
Surgical Intervention
The patient underwent an L5-S1 hemilaminectomy via a midline incision. Intraoperatively, a dark, hemorrhagic, fibrous tumor was identified and completely removed after subtotal debulking under microscopic visualization. Oncological margins were not pursued as malignancy was not initially suspected. Histopathology revealed epithelioid, spindle-shaped and polygonal cells with prominent nucleoli and abundant melanin. Immunohistochemistry was positive for S100, HMB-45 and Melan-A, with a high Ki-67 index and negative PRKAR1A expression, confirming a malignant melanotic schwannoma.
Figure 3: Tumor consisting of epithelioid, spindled shaped or polygonal cells with atypical vesicular nuclei and heavy melanin.
Postoperative Course
Postoperatively, the patient experienced significant pain relief with only mild residual hypoesthesia in the S1 dermatome. She received adjuvant radiotherapy (60 Gy) for local control. Early postoperative MRI showed enhancement at the surgical site, which progressively decreased on annual follow-up scans. At 51 months, the patient remained asymptomatic with no evidence of recurrence or metastasis (Table 1).
Table 1: Summary of the clinical course.
Based on a comprehensive search of two electronic databases (PubMed and Embase), our initial screening identified a total of 232 articles, of which 70 (the references are available in the appendix section) met all predefined inclusion and exclusion criteria, collectively reporting on 118 individual patients (PRISMA available in Supplementary material). To the best of our knowledge, this constitutes the most comprehensive literature review of spinal melanotic schwannoma cases published to date.
The literature data review is summarized in a Table available in the supplementary material section. The average age at diagnosis was 43.6 (11-84) years, with an almost equal sex distribution: 60 males and 58 females. The most commonly affected spinal region was the lumbosacral segment (n = 52), followed by the thoracic (n = 39) and cervical (n = 28) regions. Clinical presentation typically involved localized pain and neurological symptoms (Table 2).
Table 2: Key features extracted from the included studies.
Gross total resection was the most frequently reported surgical approach (n = 59). Surgical treatment was performed in the vast majority of cases. When adjuvant therapy was applied, radiotherapy was the most commonly used modality (n = 31). In total, 33 cases received some form of adjuvant therapy (radiotherapy and/or chemotherapy), while 39 studies explicitly reported no adjuvant treatment. In 46 studies, this information was not provided (Table 3).
Figure 4: Adjuvant therapy for melanotic schwannoma of the spine.
Parameter | Findings |
Neurological outcome | Favorable (improvement or stabilization) in 38 patients |
Tumor recurrence | Documented in 37 patients |
Recurrence-free | 58 patients |
Recurrence data unavailable | 23 patients |
Studies reporting follow-up | 89 studies |
Follow-up duration | 2-300 months |
Mean follow-up | 38.3 months |
Median follow-up | 18 months |
Mortality | 21 patients |
Median time to death | 12 months postoperatively |
Table 3: Summary of clinical outcomes and follow-up data.
Melanotic Schwannoma (MS) is a rare nerve sheath tumor characterized by melanin-producing Schwann cells, first described by Millar in 193212. It is considered a distinct entity due to its potential for aggressive behavior, including local recurrence and distant metastasis. MS may occur sporadically or in association with Carney complex; in our review, most cases were sporadic. Although it can affect both young and older adults, no pediatric cases were identified, underscoring its extreme rarity in this age group.
MS and conventional schwannomas share clinical and anatomical features, including slow growth and nerve root involvement. Both show strong post-contrast enhancement, but MRI signal differences help distinguish them: MS typically presents T1 hyperintensity and T2 iso- or hypointensity due to melanin, unlike conventional schwannomas, which are usually T1 iso-/hypointense and T2 hyperintense [8,13]. Additional features such as hemorrhage, calcifications and Carney complex also support the diagnosis [1,10]. Histopathology and immunohistochemistry (HMB-45, S100 positivity) confirm the diagnosis (Table 4) [1,9,10].
Table 4: MRI features- conventional vs. melanotic schwannoma.
Gross Total Resection (GTR) remains the preferred treatment and is associated with lower recurrence and metastasis rates8. The role of adjuvant therapy is unclear and its use varies, though it may be considered in residual or recurrent disease14. Given its unpredictable course, long-term follow-up is essential. Most reported follow-ups were under 25 months, likely underestimating late events. Although once considered benign, growing evidence including the series by Torres-Mora, et al., indicates that melanotic schwannoma carries malignant potential, with disease-related deaths occurring despite gross total resection and adjuvant therapy, highlighting the uncertainty surrounding its prognosis and optimal treatment [15]. For rare tumors such as melanotic schwannoma, systematic reviews of case reports are essential. The strength of this study is its ability to synthesize dispersed clinical evidence into actionable insights regarding prognosis, recurrence and survival, thereby supporting more informed clinical decision-making (Table S1-4).
Melanotic schwannoma is a rare nerve sheath tumor with a more aggressive biological behavior than traditionally recognized. Gross total resection remains the mainstay of treatment; however, the role of adjuvant therapy remains uncertain and should be individualized. Given the rarity of the disease and the reliance on heterogeneous case reports, current evidence is limited, yet the risk of late recurrence or metastasis supports the need for long-term MRI surveillance. Future multicenter studies and dedicated registries are required to better define prognostic factors and optimize management strategies.
The authors declared no potential conflicts of interest with respect to the research, authorship and/or publication of this article.
This research did not receive any specific grant from funding agencies in the public, commercial or non-profit sectors.
None
Not applicable.
The project did not meet the definition of human subject research under the purview of the IRB according to federal regulations and therefore, was exempt.
Informed consent was taken for this study.
All authors contributed equally to this paper.
Figure S1: PRISMA flow diagram.
Patient | Authors and year | Age | Sex | Location | Size (mm) | Clinical presentation | Surgery (gross ressection x subtotal x partial x biopsy) | Adjuvant treatment (QTX x RTX x Imunoherapy) | Neurological outcome | Survival rate (months) | Recurrence | Follow-up (months) |
1 | Yan, et al., 2023¹ | 33 | M | Sacral (S2) | 20x25x20 | 2 months of low back pain and a half-month of right thigh numbnes | Gross total ressection | RTX | No déficits | Yes | No | 18 |
2 | ER, et al., 2007² | 54 | M | Cervical (C0-C1) | 20x30x20 | 2mo neck pain and right arm hypoesthesia, worsening to right hemiparesis | Gross total ressection | No | N/A | Yes | No | 24 |
3 | Sahay, et al., 2020³ | 35 | M | Lumbar (L2-L3) | 14×12 | lower back pain and pain in the right knee with weakness for 1.5 months | Subtotal resection | RTX | No deficits | Yes | No | 6 |
4 | Sahay, et al., 2020³ | 44 | M | Cervical (C1-C2) | N/A | tingling and numbness in both upper limbs | Subtotal resection | No | N/A | Yes | Yes | 30 |
5 | Sahay, et al., 2020³ | 35 | F | Lumbar (L3) | N/A | progressive left thigh pain | Subtotal resection | RTX and Imunotherapy | N/A | Yes | Yes | 36 |
6 | Sahay, et al., 2020³ | 50 | F | Cervical (C6) | 11x32x20 | bilateral lower limb weakness, paraesthesia since past 4 to 5 months and bladder incontinence since 1 week | Subtotal resection | RTX | Stable, no new déficit | Yes | No | N/A |
7 | Xiang, et al., 2023 | 60 | M | Thoracic (T6-T7) | 43x30x61 | 2-year history of chest and back pain. | Biopsy | No | N/A | N/A | N/A | N/A |
8 | Cheng, et al., 2017 | 47 | M | Thoracic (T4-T5) | 18x21x44 | back pain, hypoesthesia below mamiillary level and left-leg weakness that progressively got worse over a period of fourteen months | Subtotal resscetion | No | Worsening legs strength | Yes | Yes | 72 |
9 | Hou, et al., 2020 | 41 | F | Cervical (C2-C3) | 40×11 | 8-month history of neck pain and 6-month history of numbness and weakness of the upper extremities. | Gross total ressection | RTX after recurrence | No déficits | Yes | Yes | 151 |
10 | Khoo, et al., 2016 | 36 | F | Lumbar-Sacral (L5-S1) | N/A | 4-year history of left hip pain, with progressive radiantiion to the left lateral leg and little toe complained of progressive symptoms with new radiation of | Biopsy -> gross total ressection | N/A | N/A | Yes | 10 months FO osseous tumour infiltration adjacent to the previous resection site | 10 |
11 | Khoo, et al., 2016 | 20 | M | Sacral (S1) | 30 | 4 year low back pain, worse on the left side | Biopsy -> gross total ressection | N/A | N/A | N/A | N/A | N/A |
12 | Khoo, et al., 2016 | 46 | M | Lumbar (L3) | N/A | 2 year of back and left leg pain with intermittent left leg numbness | Gross total ressection | QTX and RTX | N/A | 30 | Yes | 30 |
13 | McGravan et al., 1979 | 12 | M | Thoracic (T2) | 6×8 | gait disturbance and urinary incontinence | Gross total ressection | No | Mild spastic left leg paresis | Yes | No | 60 |
14 | McGravan, et al., 1979 | 49 | F | Cervical-thoracic (C7-T1) | 70×50 | 3-monts pain right forearm and fingers. Atrophy and paresis intrinsic msucules right hand | Gross total ressection | No | No déficits | Yes | No | 24 |
15 | Hoover, et al., 2012 | 62 | F | Thoracic (T12) | 12x10x11 | several years pain in thighs | Gross total ressection | No | diffuse mild corticospinal weakness in the lower extremities bilaterally with spasticity in the right lower extremity. Sensory deficits in the lower extremities resulting in sensory ataxia | Yes | No | 10 |
16 | Paris, et at., 1979 | 49 | F | Cervico-thoracic (C7-T1) | 60x45x22 | 2-year pain in right arm | Gross total ressection | RTX | No déficits | Yes | No | 48 |
17 | Sun, et al., 2023 | 55 | F | Lumbar-Sacral (L5-S1) | 22×19 | right waist to hip swelling pain | Gross total ressection | RTX | No déficits | Yes | No | 12 |
18 | Hall, et al., 2022 | 18 | F | Sacral (S1-S2) | 29×28 | progressive lower back pain and right lower extremity radicular pain for several years | Subtotal -> gross total ressection | RTX | No déficits | Yes | No | 30 |
19 | Tawk, et al., 2005 | 61 | M | Thoracic (T7-T9) | N/A | 2-year history of worsening thoracic back pain and weakness of the lower extremities | Gross total ressection | RTX and QTX | motor function improved progressively on the right side. Remained weak on the left side and retained a sensory level at T8 with paresthesia and numbness | 11 | Yes | 11 |
20 | Santaguida, et al., 2004 | 35 | M | Cervical (C4-C5) | N/A | neck pain that radiated to his right subscapular region. His symptoms worsened progressively, developed right C5 paresthesia accompanied by clonus of his right foot and ankle and gait dysfunction | Gross total ressection | RTX after recurrence | Symptons improvement | Yes | Yes | 48 |
21 | Güzel E, et al., 2016 | 36 | M | Lumbar-Sacral (L5-S1) | 20x20x15 | Low back pain radiating the right leg, with progressive leg weakness and numbness | Subtotal ressection | No | Improvement pain and weakness | Yes | No | 6 |
22 | McCann and Hain, 2023 | 40 | M | Thoracic (T8-T11) | 31×11 | 2-month history of progressive bilateral leg weakness and pain radiated bilaterally to the lower extremities | Gross total ressection | QTX | Worsening legs strength and sensibility. Improvement back pain | Yes | No | 3 |
23 | Acciarri, et al., 1999 | 44 | F | Thoracic (T2-T3) | 30 | 10-year history of numbness and paraesthesiae of both lower lim bs and weakness to the right leg | Gross total ressection | No | Improvement legs strength and sensibility | Yes | No | 4 |
24 | Mouchaty, et al., 2008 | 56 | F | Thoracic-Lumbar (T12-L1) | 30-40 | Legs weakness | Gross total ressection | No | Improvement legs strength | Yes | No | 12 |
25 | Zhao, et al., 2011 | 46 | M | Cervical (C6-C7) | 17x21x15 | pain and distension in his neck for 2 years and numbness of his left hand for 1 year; | Gross total ressection | RTX | No deficits | Yes | No | 16 |
26 | Li and Dai, 2019 | 61 | F | Lumbar (L1) | 16×45 | progressive weakness of the lower limbs and increasing pain and numbness around the left lower extremity 3 years prior to admission | Gross total ressection | N/A | N/A | N/A | N/A | N/A |
27 | De Cerchio, et al., 2006 | 53 | M | Thoracic (T9-T10) | 25 | pain in his right chest and upper limb | Gross total ressection | No | Pain improvement | Yes | No | 24 |
28 | Marton, et al., 2007 | 30 | F | Cervical (C2-C3) | 20 | right cervical pain and cervical muscle contractures for six months. mild raight arm paresis | Gross total ressection | No | Pain improvement | Yes | Yes | 12 |
29 | Solomou, et al., 2020 | 45 | F | Cervical (C6) | N/A | one-year history of insidious neck pain radiating to the shoulder girdle, left arm and thumb, with associated paraesthesia in the same distribution | Subtotal | RTX and Imunotherapy | Pain improvement | 15 | Yes | 15 |
30 | Takatori, et al., 2020 | 39 | M | Lumbar (L4) | N/A | low back pain and numbness of the left leg | Subtotal | RTX | Pain and numbness improvement | 22 | Yes | 22 |
31 | Hu and Wang, 2018 | 40 | M | Cervical (C1-C2) | 15×10 | left arm numbness that gradually worsened | Partial | No | left arm numbness partially subsided | Yes | No | 2 |
32 | Biju, et al., 2020 | 38 | F | Lumbar-Sacral (L5-S1) | N/A | sudden‐onset dull ache in her lower back region followed by sharp radicular pain radiating down from her left gluteal region to the foot | Gross total ressection | No | recovered well with improvement in both her back and radicular pain | Yes | No | N/A |
33 | Gregorios, et al., 1982 | 45 | F | Thoracic (T2) | 30×30 | insidious onset of numbness and tingling over her lower abdomen and upper legs; later developed urinary urgence | Subtotal | No | markedly paraparetic, presumably because of spinal cord manipulation | N/A | N/A | N/A |
34 | Soyland, et al., 2021 | 53 | M | Thoracic (T8-T9) | 44x21x20 | 2-day history of sudden-onset left chest pain radiating to his left back | Gross total ressection | No | doing well other than some persisting incisional pain | Yes | No | 6 |
35 | Erlandson, 1985 | 36 | M | Lumbar-Sacral (L5-S1) | 20x10x5 | dull aching pain in the left hip and left lower back in addition to paresthesias along the lateral aspect of the left foot of 3 years duration. | Gross total ressection | No | neurologic impairment improved | Yes | No | 92 |
36 | Li and Chen, 2015 | 62 | M | Thoracic (T7) | 50x30x20 | routine physical examination | Gross total ressection | No | Stable | Yes | No | 30 |
37 | Mohamed, et al., 2014 | 43 | M | Thoracic (T9-T10) | 26×12 | left-leg weakness that gradually got worse | Gross total ressection | his power in his right leg had reduced to 3/5 throughout all muscle groups and he had developed urinary incontinence requiring catheterisation | Yes | No | 3 | |
38 | Chandran, et al., 2018 | 25 | M | Cervical (C2) | N/A | nonspecific neck pain | Gross total ressection | No | N/A | Yes | No | 60 |
39 | Bakan, et al., 2015 | 31 | F | Thoracic (T4-T5) | 25 | back pain | Gross total ressection | No | uneventfull | Yes | No | 6 |
40 | Alamer and Tampieri, 2019 | 45 | F | Thoracic (T5-T6) | N/A | back pain | Gross total ressection | No | N/A | Yes | No | 23 |
41 | Alamer and Tampieri, 2019 | 54 | F | Sacral (S2-S3) | N/A | back pain | Gross total ressection | No | N/A | Yes | No | 15 |
42 | Arvanitis, 2010 | 36 | M | Lumbar (L3) | 178x170x97 | increasing back pain radiated to the right side of the abdomen and a recent 20 pound weight loss; right leg weakness | Partial | N/A | N/A | N/A | N/A | N/A |
43 | Chen and Gu, 2015 | 47 | M | Thoracic (T2-T4) | 45x25x15 | pain in chest and back; numbness and weakness in lower extremities; occurrence of urinary retention | Gross total ressection | No | sensory disturbances decreased, strength improvement; deep and shallow sensation in both lower extremities was normal; urinary retention remarkably improved | Yes | No | 6 |
44 | Faria, et al., 2013 | 32 | F | Cervical (C4-C5) | 37x30x16 | cervical pain and left arm progressive weakness | Gross total ressection | RTX / QTX and Radiosurgery after recurrency | a patent deficit of left shoulder abduction and paresthesia persist related to the nervous section. | 9 | Yes | 9 |
45 | Yokota, et al., 2012 | 64 | M | Cervical (C7) | 45x22x17 | 3-year history of sensory changes in his left arm and a 1-month history of gait disturbance | Subtotal | RTX after recurrence | symptoms were remarkably improved | 12 | Yes | 12 |
46 | Bosman, et al., 1995 | 43 | M | Lumbar (L4-L5) | N/A | posterior leg pain and hypostenia of the left lower limb | Gross total ressection | N/A | the patient had overcome neurologic impairment | N/A | N/A | N/A |
47 | Shabani, et al., 2015 | 54 | M | Cervical (C5) | 21x19x15 | Incidental finding -> 18 month follow-up with significant pain radiating from the left cervical region into the left thumb and index finger. | Gross total ressection | No | N/A | 7 | Yes | 7 |
48 | Solomon, et al., 1987 | 69 | M | Cervical (C0-C3) | N/A | loss of pain and temperature sensation in distal left leg; weakness of right arm with hand atrophy; weaknesse of left leg; decreased pain and temperature sensation in left upper extremity | Gross total ressection | N/A | increased difficulty with vibratory and position sensation on the right side of the body | N/A | N/A | N/A |
49 | Terry, et al., 2022 | 48 | F | Sacral (S2) | 90x85x70 | severe lower back and right buttock pain with right thigh numbness over a period of one year; difficulty urinating and defecating. | Biopsy -> Gross total ressection | QTX and RTX | dramatic improvement in pain | 18 | Yes | 18 |
50 | Vallat-Decouvelaere, et al., 1999 | 35 | F | Lumbar (L3-L5) | N/A | Lumbar and sciatic pain for 3 years | Gross total ressection | N/A | N/A | 72 | Yes | 72 |
51 | Vallat-Decouvelaere, et al., 1999 | 27 | M | Lumbar (L5) | N/A | Lumbar and left sciatic pain | Gross total ressection | N/A | N/A | 72 | No | 72 |
52 | Vallat-Decouvelaere et al., 1999 | 34 | M | Cervical (C1) | N/A | Cervical pain for 1 year, right sensitive deficit, left motor deficit | Partial | N/A | N/A | Yes | No | 84 |
53 | Vallat-Decouvelaere et al., 1999 | 45 | F | Thoracic (T6) | N/A | Dorsal pain for 1 year | Gross total ressection | N/A | N/A | 36 | No | 36 |
54 | Vallat-Decouvelaere, et al., 1999 | 41 | F | Sacral (S1) | N/A | Dorsal pain and sciatic pain for 4 years | Partial | N/A | N/A | Yes | No | 72 |
55 | Buhl, et al., 2004 | 28 | M | Lumbar-Sacral (L5-S1) | 60×50 | 4 weeks of low back ache and sciatic pain on the right side for S1. | Gross total ressection | No | paresis of the S1 root on the right side and hypaesthesia | Yes | No | 30 |
56 | Marchese and McDonald, 1990 | 72 | F | Cervical (C4-C6) | 20×15 | more than 20 years for progressive lower extremity weakness; burning dysesthesiae in both feet and having difficulty controlling her bladder and bowels, progressive weakness on upper limbs | Subtotal | N/A | uneventful recovery and regained significant function in both upper extremities | N/A | N/A | N/A |
57 | Grosshans, et al., 2020 | 23 | M | Cervical (C2-C3) | N/A | Cervical myelopathy | Gross total ressection | RTX after recurrence | N/A | Yes | Yes | 180 |
58 | Grosshans, et al., 2020 | 67 | M | Thoracic (T8-T9) | N/A | Thoracic myelopathy | Subtotal | RTX | N/A | Yes | No | 14 |
59 | Grosshans, et al., 2020 | 43 | F | Lumbar (L4-L5) | N/A | Radiculopathy | Subtotal | No | N/A | Yes | No | 2 |
60 | Shen, et al., 2021 | 29 | F | Lumbar (L2-L3) | 43×31 | 1-day history of backache; mild weakness and hypermyotonia in the right leg | Biopsy | QTX | recovered well | Yes | No | 12 |
61 | Shields, et al., 2011 | 65 | F | Thoracic (T6-T8) | 30x20x15 | history of mid-thoracic spinal pain. | Partial | RTX | N/A | 8 | Yes | 8 |
62 | Shields, et al., 2011 | 33 | M | Lumbar-Sacral (L5-S1) | N/A | low back pain and right L5 radiculopathy. | Gross total ressection | RTX and QTX after recurrence | N/A | 42 | Yes | 42 |
63 | Ng and Munoz, 2016 | 20 | F | Sacral (S1) | N/A | history of back pain radiating down the right leg into the foot leading to numbness in the S1 distribution. | Partial | RTX | N/A | Yes | No | 12 |
64 | Mennemeyer et al., 1979 | 25 | M | Thoracic (T7) | 25 | progressive numbness in left leg | Gross total ressection | No | completely recovered | Yes | No | 24 |
65 | Mennemeyer, et al., 1979 | 23 | F | Thoracic-Lumbar (T10-L2) | 25 | weakness of both lower limbs with back pain | Gross total ressection | RTX after recurrence | completely recovered | Yes | Yes | 61 |
66 | Mennemeyer, et al., 1979 | 36 | M | Sacral (S1) | 10x15x20 | low back pain with radiation down the posterior aspect of left leg | Gross total ressection | No | completely recovered | Yes | No | 9 |
67 | Zaninovich, et al., 2019 | 22 | M | Thoracic (T9-T11) | 61 | intermittent back pain becoming more frequent until it worsened and he developed paraparesis, that became paraplegia, with complete anesthesia below the umbilicus, absent lower extremity deep tendon reflexes, rectal tone absent and acute urinary retention with priapism. | Subtotal | RTX after recurrence | remained paraplegic with T11 sensory level; bowel function had returned to normal, but bladder function did not return | Yes | Yes | 33 |
68 | Torres-Mora, et al., 2014 | 21 | F | Cervical (C7) | N/A | N/A | N/A | N/A | N/A | Yes | No | 300 |
69 | Torres-Mora, et al., 2014 | 66 | F | Thoracic (T10) | N/A | N/A | N/A | N/A | N/A | Yes | Yes | 6 |
70 | Torres-Mora, et al., 2014 | 23 | F | Lumbar (L4) | 25X15X5 | N/A | N/A | N/A | N/A | Yes | No | 44 |
71 | Torres-Mora, et al., 2014 | 67 | F | Thoracic (T10) | 25 | N/A | N/A | N/A | N/A | 5 | No | 5 |
72 | Torres-Mora, et al., 2014 | 44 | F | Thoracic (T5-T6) | N/A | N/A | N/A | N/A | N/A | 36 | Yes | 36 |
73 | Torres-Mora, et al., 2014 | 39 | M | Thoracic (T3) | 30 | N/A | N/A | N/A | N/A | Yes | Yes | 108 |
74 | Torres-Mora, et al., 2014 | 47 | M | Lumbar (L3-L4) | 14X13 | N/A | N/A | N/A | N/A | 10 | No | 10 |
75 | Torres-Mora, et al., 2014 | 61 | M | Thoracic (T6-T8) | 60X40 | N/A | N/A | N/A | N/A | 10 | No | 10 |
76 | Torres-Mora, et al., 2014 | 47 | M | Cervical (C5) | 15X14 | N/A | N/A | N/A | N/A | Yes | Yes | 48 |
77 | Torres-Mora, et al., 2014 | 62 | F | Thoracic (T11) | 14 | N/A | N/A | N/A | N/A | Yes | No | 25 |
78 | Torres-Mora, et al., 2014 | 27 | M | Lumbar (L2-L3) | N/A | N/A | N/A | N/A | N/A | Yes | Yes | 128 |
79 | Torres-Mora, et al., 2014 | 69 | M | Sacral | N/A | N/A | N/A | N/A | N/A | Yes | No | 1 |
80 | Torres-Mora, et al., 2014 | 32 | F | Lumbar-Sacral (L5-S1) | 25 | N/A | N/A | N/A | N/A | Yes | No | 18 |
81 | Torres-Mora, et al., 2014 | 32 | F | Cervical (C2) | 28X11 | N/A | N/A | N/A | N/A | Yes | Yes | 72 |
82 | Torres-Mora, et al., 2014 | 32 | M | Cervical (C2) | 31X20X13 | N/A | N/A | N/A | N/A | 12 | No | 12 |
83 | Torres-Mora, et al., 2014 | 25 | F | Sacral | 70 | N/A | N/A | N/A | N/A | 6 | Yes | 6 |
84 | Torres-Mora, et al., 2014 | 62 | F | Cauda Equina | N/A | N/A | N/A | N/A | N/A | Yes | No | 168 |
85 | Torres-Mora, et al., 2014 | 19 | M | Sacral (S1) | N/A | N/A | N/A | N/A | N/A | Yes | No | 7 |
86 | Torres-Mora, et al., 2014 | 30 | M | Sacral (S1) | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A |
87 | Torres-Mora, et al., 2014 | 17 | F | Sacral (S1) | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A |
88 | Torres-Mora, et al., 2014 | 63 | M | Sacral | 50X35X10 | N/A | N/A | N/A | N/A | N/A | N/A | N/A |
89 | Torres-Mora, et al., 2014 | 40 | F | Lumbar (L3-L4) | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A |
90 | Torres-Mora, et al., 2014 | 52 | F | Thoracic-Lumbar | 19X15 | N/A | N/A | N/A | N/A | N/A | N/A | N/A |
91 | Torres-Mora, et al., 2014 | 28 | M | Thoracic (T10) | 30 | N/A | N/A | N/A | N/A | N/A | N/A | N/A |
92 | Torres-Mora, et al., 2014 | 84 | F | Conus Medullaris | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A |
93 | Torres-Mora, et al., 2014 | 45 | M | Thoracic (T7) | 20X8X4 | N/A | N/A | N/A | N/A | N/A | N/A | N/A |
94 | Torres-Mora, et al., 2014 | 75 | M | Lumbar (L2) | 35X20X15 | N/A | N/A | N/A | N/A | N/A | N/A | N/A |
95 | Torres-Mora, et al., 2014 | 47 | F | Thoracic (T12) | 18X17X11 | N/A | N/A | N/A | N/A | N/A | N/A | N/A |
96 | Torres-Mora, et al., 2014 | 57 | F | Lumbar (L3) | 25 | N/A | N/A | N/A | N/A | N/A | N/A | N/A |
97 | Martin-Reay, et al., 1991 | 32 | M | Sacral (S3-S4) | 30X25X15 | sudden onset of left buttock and coccygeal pain made worse by sitting | Subtotal | N/A | Pain improvement | N/A | N/A | N/A |
98 | Yeom, et al., 2022 | 58 | F | Thoracic (T11-T12) | 41x16x13 | low back pain, paresthesia and cold sensation in both legs for several years. No motor dysfunction in either leg | Gross ressection | No | low back pain and paresthesia in both lower legs were all improved | Yes | No | N/A |
99 | Yeom, et al., 2022 | 72 | M | Thoracic (T11) | 10x6x6 | a 6-mo history of low back pain and paresthesia in both legs and a 3-mo history of gait disturbance | Biopsy | No | Symptons maintance | Yes | No | 36 |
100 | Azarpira, et al., 2009 | 37 | M | Lumbar (L2) | 35 | 8-month history of lower back pain | Gross ressection | No | N/A | Yes | No | 4 |
101 | Mandybur, 1974 | 59 | M | Thoracic (T7) | N/A | 17-year history of radicular pain and 9 mo weakness in the legs and hesitancy in urination prior apresentation | Subtotal | No | weakness improvement | Yes | Yes | 20 |
102 | Leger, et al., 1996 | 36 | M | Cervical (C4) | N/A | sensory disorders in the region of the left C4 spinal root for months | Subtotal | No | N/A | Yes | Yes | N/A |
103 | Cummings, et al., 1999 | 51 | M | Sacral (S2) | 35×30 | 8-mo history of lower back pain | Biopsy | No | Stable | Yes | Yes | N/A |
104 | Zonenshayn, et al., 2000 | 27 | F | Lumbar (L2-L3) | 11×7 | 2-month history of left-sided hip, typical of L-2-distribution sciatica. slight weakness in the hip flexors and knee extensors on the left | Gross | No | Pain improvement | Yes | No | 6 |
105 | Woodford, et al., 2022 | 60 | M | Cervical (C2-C3), cauda equina | N/A | Numbness/weakness in his hands and neck pain. low back pain and decreased perineal sensation. | Cervical: Gross total ressection. Lumbar: RT | RTX and Imunotherapy | N/A | Yes | Yes | 34 |
106 | Woodford, et al., 2022 | 21 | F | Lumbar: L5-S1 | 45×40 | Back pain | Ressection (total ou partial?) | RTX and Imunotherapy | Death | N/A | Yes | N/A |
107 | Shanmugam, et al., 2015 | 67 | M | Thoracic (T8-T12) | N/A | weakness and numbness in lower limbs | Surgery (ressection, partial or biopsy?) | N/A | N/A | N/A | N/A | N/A |
108 | Georgiev, et al., 2021 | 61 | M | Lumbar: L3 | 50×46 | low back pain, progressive numbness and stiffness in the right lower limb | Gross total ressection | RTX | Mild hyperesthesia along the L3 dermatom. Peroneal nerve paresis | Yes | Yes | 16 |
109 | Jackson, et al., 2021 | 60 | F | Sacral: S1 | 38 | right-sided lower back and leg pain | Gross total ressection | RTX and QTX | Death | 36 | Yes | 36 |
110 | Aprile, et al., 2000 | 70 | F | Lumbar: L3 | 10 | Low back and right leg pain. paraparesis and bilateral hyperalgesia | Gross total ressection | N/A | N/A | Yes | N/A | N/A |
111 | Aprile, et al., 2000 | 60 | M | Lumbar: L4-L5 | N/A | Lumbar pain, Pain in the left leg. hyperalgesia of the leg and hypoaesthesia radiating into the L5-S1 region. | Gross total ressection | N/A | N/A | Yes | N/A | N/A |
112 | Lowman and Livolsi, 1980 | 26 | F | Cervical: C5-C6 | N/A | pain and numbness radiating upwards from the region ofthe right foot. absent vibratory sense and diminution of both pain and touch on the right side | Gross total ressection | No | Improviment. No deficits | Yes | No | 204 |
113 | Lowman and Livolsi, 1980 | 17 | F | Thoracic-lumbar: T12-L1 | N/A | back pain and left-sided sciatica. | Subtotal | RTX | walks with crutches | Yes | No | 168 |
114 | Velz, et al., 2018 | 32 | F | Thoracic: T10-T12 | 46x42x58 | intermittent thoracic and abdominal pain radiating to the right sid | Gross total ressection | RTX | No deficits | Yes | Yes | 3 |
115 | French, et al., 2005 | 76 | F | Thoracic-Lumbar: T11-L5 | N/A | Lumber back pain. right-sided sensorineural deafness, gait ataxia with falling to right. paraparesis | Biopsy | No | Death | 2 | No | 2 |
116 | Shui, et al., 2022 | 21 | F | Lumbar-sacral: L5-S1 | 45×40 | left L5 radicular pain accompanied by L5 hypoesthesia | Gross total ressection | RTX | the patient was discharged wheelchair-bound | Yes | Yes | 7 |
117 | Bonomo, et al., 2023 | 28 | F | Cervical: two lesions C5-C6 and C6-C7 | 20×10 (larger tumor) | cervical pain radiating to the right arm. mild weakness in the right arm and dysesthesia in the C5-C6 right dermatome | Gross total ressection | No | strength recovery, but dysesthesia slightly improved | Yes | No | 12 |
118 | Chakravarthy, 2012 | 45 | F | Lumbar-sacral: L5-S1 | 21x15x18 | Low back pain | Gross total ressection | No | Improviment. No deficits | Yes | No | 18 |
Table S1: Summary of all studies (n=118).
CARE Checklist | |
Description | |
1. Title | Malignant Melanotic Schwannoma of the Sacrum in a Young Woman: A Case Report and 51-Month Follow-Up |
2. Keywords | Melanotic schwannoma, spinal tumor, sacral nerve sheath tumor, malignant peripheral nerve sheath tumor, case report |
3. Abstract | Structured abstract provided (Introduction, Case, Outcome, Conclusion) |
4. Introduction | Brief overview of melanotic schwannomas, significance of case |
5. Patient Information | 21-year-old woman, no family history, 2-year history of back pain and radiculopathy |
6. Clinical Findings | S1 dermatomal hypoesthesia, radicular pain, no motor deficit |
7. Timeline | Table provided with sequence of clinical events |
8. Diagnostic Assessment | EMG, MRI, histopathology, immunohistochemistry |
9. Therapeutic Intervention | L5-S1 hemilaminectomy, microscopic total resection, adjuvant radiotherapy |
10. Follow-up and Outcomes | 51 months of follow-up, no recurrence, asymptomatic |
11. Discussion | Review of diagnosis, treatment approach, comparison with literature, importance of long-term follow-up |
12. Patient Perspective (opt.) | Not included (optional) |
13. Informed Consent | Obtained and documented |
Table S2: Care checklist (case report).
Study ID | Demographics described | History/timeline clear | Clinical condition on presentation | Diagnostic tests/results described | Intervention clearly described | Post-intervention condition described | Adverse events described | Takeaway lessons present | Total Score | Risk of Bias |
Acciarri, N; 1999 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Alamer, A 2019 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Aprile, I; 2000 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Arvanitis, LD 2010 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Azarpira, N; 2009 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Bakan, S; 2015 | Y | Y | Y | Y | Y | Y | N | Y | 7 | low |
Biju, R; 2020 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Bonomo, G; 2023 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Bosman, C; 1995 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Buhl, R; 2004 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Cerchio, L; 2006 | Y | Y | Y | Y | Y | Y | N | Y | 7 | low |
Chakravarthy, H; 2012 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Chandran, R; 2018 | Y | Y | Y | Y | Y | Y | N | Y | 7 | low |
Chen, D; 2015 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Cheng, X; 2017 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Cummings TJ, ; 1999 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Er, U; 2007 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Erlandson, RA 1985 | Y | Y | Y | Y | Y | Y | Y | N | 7 | low |
Faria, MHG; 2013 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
French, P.J.; 2005 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Georgiev, G.K; 2021 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Gregorios, JB; 1982 | Y | Y | Y | Y | Y | Y | N | Y | 7 | low |
Grosshans, HK; 2020 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Güzel, E; 2016 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Hall, J; 2022 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Hoover, ; 2012 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Hou, Z; 2020 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Hu, L, C Wang 2018 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Jackson, C; 2021 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Khoo, M; 2016 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Leger, F; 1996 | Y | Y | Y | Y | Y | Y | N | Y | 7 | low |
Li, B and Chen, Q 2015 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Li, X; 2019 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Lowman, R.M.; 1980 | Y | Y | Y | Y | Y | Y | N | Y | 7 | low |
Mandybur, TI; 1974 | Y | Y | Y | Y | Y | Y | N | Y | 7 | low |
Marchese, MJ 1990 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Martin-Reay, DG; 1991 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Marton, E; 2007 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
McCann, M; 2023 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
McGravan, W; 1979 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Mennemeyer, RP; 1979 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Mohamed, M; 2014 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Mouchaty, H; etl al 2008 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Ng, J and Munoz, DG 2016 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Paris, F; etl at 1979 | Y | Y | Y | Y | Y | Y | Y | N | 7 | low |
Sahay, A; 2020 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Santaguida, C; 2004 | Y | Y | Y | Y | Y | Y | N | Y | 7 | low |
Shabani, S; 2015 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Shanmugam, S; 2015 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Shen, XZ; 2021 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Shields, LBE; 2011 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Shui, C; 2022 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Solomon, RA; 1987 | Y | Y | Y | Y | Y | Y | N | Y | 7 | low |
Solomou, G; 2020 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Soyland, DJ; 2021 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Sun, Z; 2023 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Takatori, N; 2020 | Y | Y | Y | Y | Y | Y | N | Y | 7 | low |
Tawk, R; 2005 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Terry, M; 2022 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Torres-Mora, J; 2014 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Vallat-Decouvelaere AV; 1999 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Velz, J; 2018 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Woodford, R; 2022 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Xiang, Z; 2023 | Y | Y | Y | Y | Y | Y | N | Y | 7 | low |
Yan, X; 2023 | Y | Y | Y | Y | Y | Y | N | Y | 7 | low |
Yeom, JA; 2022 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Yokota, H; 2012 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Zaninovich, O; 2019 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Zhao, Q; 2011 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Zonenshayn, M; 2000 | Y | Y | Y | Y | Y | Y | Y | Y | 8 | low |
Table S3: JBI appraisal of the 70 studies.
Section and Topic | Item # | Checklist Item | Reported on Page(s) |
Title | 1 | Identify the report as a systematic review. | Title page, p. 1 |
Abstract | 2 | Provide a structured summary including background, objectives, methods, results and conclusions. | Abstract, p. 2-3 |
Introduction | |||
Rationale | 3 | Describe the rationale for the review in the context of what is already known. | Introduction, p. 4-5 |
Objectives | 4 | Provide an explicit statement of the objective(s) or question(s) the review addresses. | p. 5 |
Methods | |||
Eligibility Criteria | 5 | Specify the inclusion and exclusion criteria for the review and how studies were grouped for the syntheses. | Methods – Systematic review, p. 6-7 |
Information Sources | 6 | Specify all databases and other sources searched (e.g., reference lists), with the last search date. | Methods – Systematic review, p. 6-7 |
Search Strategy | 7 | Present the full search strategy for each database, including all search terms and filters used. | Methods – Systematic review, p. 6-7 |
Selection Process | 8 | Specify the methods used to decide whether a study met inclusion criteria, including number of reviewers and how disagreements were resolved. | Methods – Systematic review, p. 6-7 |
Data Collection Process | 9 | Specify how data were collected from reports, including number of reviewers and how disagreements were resolved. | Methods – Systematic review, p. 6-7 |
Data Items | 10 | List and define all outcomes for which data were sought and describe any assumptions made. | Methods – Systematic review, p. 6-7 |
Risk of Bias in Studies | 11 | Describe any methods used to assess risk of bias in included studies. | Methods – Systematic review, p. 6-7 |
Effect Measures | 12 | Specify the effect measures used for each outcome (e.g., risk ratio, mean difference). | Not applicable |
Synthesis Methods | 13a-13f | Describe synthesis methods, handling of data and how heterogeneity was addressed. | Methods – Systematic review, p. 6-7 |
Certainty Assessment | 15 | Describe any methods used to assess certainty in the body of evidence (e.g., GRADE). | Methods – Systematic review, p. 6-7 |
Results | |||
Study Selection | 16 | Provide the number of studies screened, assessed and included, ideally with a flow diagram. | Results – p. 13; Figure – p. 13 |
Study Characteristics | 17 | Cite each included study and present its characteristics. | Results, p. 14 Supplementary material |
Risk of Bias in Studies | 18 | Present assessments of risk of bias for each included study. | JBI Appraisal Supplementary material |
Results of Individual Studies | 19 | For all outcomes, present data for each study. | Supplementary material |
Results of Syntheses | 20 | Present summary of findings, heterogeneity and certainty (if applicable). | Results – p.14-15 |
Discussion | |||
Discussion of Results | 23a | Interpret the results in context, including limitations and implications. | Discussion – p. 11-13 |
Limitations of Evidence | 23b | Discuss limitations of the included evidence. | Discussion – p. 12-13 |
Limitations of Review Process | 23c | Discuss limitations of the review process. | Discussion – p. 13 |
Other Information | |||
Registration and Protocol | 24 | Indicate whether the review protocol was registered. | Not registered |
Support | 25 | Describe sources of financial or non-financial support. | Funding section – p. 19 |
Competing Interests | 26 | Declare any competing interests. | Conflicts of Interest – p. 19,20 |
Availability of Data/Materials | 27 | Report availability of data, code and other materials. | Supplementary material |
Table S4: PRISMA 2020 checklist.
PubMed Search Strategy
(“melanotic”[All Fields] OR (“melanocytes”[MeSH Terms] OR “melanocytes”[All Fields] OR “melanocyte”[All Fields] OR “melanocytic”[All Fields])) AND (“neurilemmoma”[MeSH Terms] OR “neurilemmoma”[All Fields] OR “schwannoma”[All Fields] OR “schwannomas”[All Fields]) AND (“spine”[MeSH Terms] OR “spine”[All Fields] OR “spines”[All Fields] OR “spine s”[All Fields])
EMBASE Search Strategy
(‘melanotic schwannoma’/exp OR ‘melanotic schwannoma’ OR ‘melanocytic schwannoma’ OR ‘pigmented schwannoma’)
AND
(‘spine’/exp OR ‘spinal cord’/exp OR ‘vertebra’/exp OR spine OR spinal OR vertebral OR vertebra OR ‘spinal canal’ OR ‘spinal root’ OR ‘spinal nerve’ OR ‘spinal tumor’ OR ‘intraspinal’ OR ‘intradural’).
, Christian Luiz Baptista Gerbelli2 , Jean Eduardo de Sousa Carvalho Dezena2 , Telmo Augusto Barba Belsuzarri3 , Tiago Kiyoshi Kitabayashi Braga2 , Fabio Veiga de Castro Sparapani1, Sérgio Cavalheiro1, Franz Jooji Onishi1*
Copyright: © 2026 The Authors. Published by Athenaeum Scientific Publishers.
This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
License URL: https://creativecommons.org/licenses/by/4.0/
Citation: Iunes EA, et al. Sacral Melanotic Schwannoma: A Systematic Review of the Literature. J Neuro Onco Res. 2026;6(1):1-22.
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