Intramedullary melanotic schwannoma: Case report and review of the literature

Abstract

Background:Intramedullary melanotic schwannomas are very rare. Only seven cases have been previously reported. This is the first reported case of such a tumor presenting with intratumoral hemorrhage closely mimicking a hemorrhagic ependymoma.Case Description:A 23-year-old female patient presented with progressive right lower extremity pain and numbness for 3 months and this was followed by acute paraparesis and urinary incontinence. Physical examination revealed sensory and motor dysfunction below T4 level. Magnetic resonance imaging of her spine showed a heterogeneous signal lesion occupying the intramedullary space with small foci of hyperintensity on T1WI and hypointensity on T2WI at the T4-5 level. She underwent emergent surgical decompression and microsurgical excision of the tumor. A histopathological diagnosis of melanotic schwannoma was made. Postoperative neurological recovery revealed progressive improvement in her examination findings.Conclusion:Among spinal cord neoplasms, melanotic schwannomas are extremely rare tumors. The similar source of Schwann cells and melanocytes, the neuroectoderm, has been suggested to be the origin of melanotic schwannomas. Intramedullary melanotic schwannomas presenting with hemorrhage tend to be mistaken with ependymoma, which by far is the most common spinal tumor to present with hemorrhage. Total surgical excision if safely possible is currently considered the ideal treatment of choice.

Rexin-G®, a tumor-targeted retrovector for malignant peripheral nerve sheath tumor: A case report

“…The ages of those afflicted vary between 10 and 84 years (7,9), although the peak incidence occurs with patients in their fourth decade (7). There have been fewer than 200 cases of PNST reported since it was first described in 1932 (10,11), with approximately 40 reported malignancies as of 2014 (12). To date, there have been no published cases of MPNST originating from the parotid gland.…”

“…The prognosis for PNST is unpredictable at best, with 10% of all cases developing metastasis (8,10,14). Although generally considered benign, the tumor is prone to malignancy and recurrence, occurring in ~20% of patients (1,8,16).…”

Intramedullary melanotic schwannoma: a rare presentation of a rare tumor. Illustrative case

“…Intramedullary MSs (IMSs) are even rarer lesions, with only 12 cases of IMSs reported in the literature as of 2022. [1][2][3][4][5][6][7][8][9][10][11][12] Hemorrhagic IMSs are rarer still, and here we present a case report describing only the second recorded instance of hemorrhagic IMS (the first was in 2014). 8 In 2016, MSs were reclassified as their own malignant type of schwannoma due to their greater malignancy than ordinary schwannomas.…”

“…[1][2][3][4][5][6][7][8][9][10][11][12] Hemorrhagic IMSs are rarer still, and here we present a case report describing only the second recorded instance of hemorrhagic IMS (the first was in 2014). 8 In 2016, MSs were reclassified as their own malignant type of schwannoma due to their greater malignancy than ordinary schwannomas. 13 However, why a peripheral nerve tumor may present in the intramedullary space is still unknown.…”

“… 1–12 Hemorrhagic IMSs are rarer still, and here we present a case report describing only the second recorded instance of hemorrhagic IMS (the first was in 2014). 8 …”