Intracephalic glomus tumor presenting as peripheral neuropathic pain and literature review

Abstract

Background: Glomus tumors are benign highly vascular neoplasms, originating from glomus body and sprout in subcutaneous layer of acral parts, particularly subangual or digital pulp locations. Extra digital glomus tumors were reported in palm, feet, ear, tongue, nose, mouth, vagina and glans penis. Extra cutaneous glomus was rarely seen in gastrointestinal tract, mesentery, mediastinum, trachea, and cervix, with infrequent occurrence in muscles, bones, periosteal, and intraneural layers. The subcutaneous layer of forearm is the most common extra digital location; however, it is exceedingly rare in intravascular layer of forearm. We are reporting an intracephalic glomus tumor presenting as peripheral neuropathic pain. This presentation was not previously reported in literature.

Case report: A 38-year-old male presented with two years history of spontaneous and nocturnal right forearm pain, provoked by exposure to cold, light touch or brushing of skin. Non painful stimulus and painless touch evoked allodynia, and hyperesthesia respectively. Neurologic examination was negative apart from focal tenderness with no sensory alterations. Grey scale and colored ultrasound, MR and CT venography demonstrated an echo poor small round and avidly enhancing lesion in right cephalic vein. Complete surgical excisional resection was performed. Gross examination revealed dark-red, well defined soft tissue tumor, and histopathology confirmed glomus tumor. Symptoms completely resolved postoperatively.

Conclusion: Intravascular glomus tumors rarely occur in forearm; and exceedingly rare to present as neuropathic pain, therefore, comprehensive history, and thorough physical examination, neuroimaging techniques, and early surgical excision will likely prevent delayed or incorrect diagnosis.