Spinal intramedullary hemangioblastoma and schwannoma collision tumor: illustrative case

Abstract

Background: Intramedullary spinal cord tumors represent a minority of intradural tumors. Among intramedullary spinal cord tumors, hemangioblastomas are uncommon, and schwannomas are extremely rare. Collision tumors are histologically distinct tumors that are intermingled and growing together.

Observations: In this report, the authors describe a patient with a cervical intramedullary collision tumor involving a hemangioblastoma and schwannoma. To the authors' knowledge, no prior spinal intramedullary collision tumor involving multiple neoplasms has been described. The patient's presentation and management are described.

Lessons: Clinicians should consider the possibility of collision tumors when evaluating intramedullary spinal cord tumors, especially when patient presentation and radiographic findings are atypical. When tumors with similar radiographic characteristics form collision tumors, distinction using preoperative imaging can be extremely challenging. In addition, surgical management of intramedullary collision tumors, like that for all intramedullary spinal cord tumors, should involve meticulous perioperative care and a methodical surgical technique. Maximal safe resection will depend upon histopathological diagnosis, anatomical location of the tumor, presence of distinct dissection planes, and stability of neuromonitoring. Finally, ongoing research on the genetics of intramedullary spinal cord tumors may identify underlying genetic links for intramedullary hemangioblastomas and schwannomas.

Keywords: GTR = gross-total resection; HBL = hemangioblastoma; HIF1α = hypoxia-inducible factor 1α; IMS = intramedullary schwannoma; IMSCT = intramedullary spinal cord tumor; MRI = magnetic resonance imaging; NF2 = neurofibromin 2; STIR = short tau inversion recovery; T1WI = T1-weighted imaging; T2WI = T2-weighted imaging; VHL = von Hippel-Lindau; collision tumor; hemangioblastoma; intramedullary spinal cord tumor; schwannoma; spine.

FIG. 1.

Contrast-enhanced sagittal T1 MRI demonstrating an avidly enhancing intramedullary spinal tumor at the C4 level.

FIG. 2.

Sagittal T2 MRI demonstrating a hypointense intramedullary tumor at C4 and extensive surrounding edema.

FIG. 3.

Schwannoma demonstrating uniform spindle cells arranged in interlacing fascicles (Antoni A pattern) (hematoxylin-eosin stain, original magnification ×400).

FIG. 4.

HBL component with foamy stromal cells and capillary vascular channels (hematoxylin-eosin stain, original magnification ×400).

FIG. 5.

Sagittal T2 MRI 4 weeks following surgery demonstrating marked improvement in the syrinx and cord edema.