Primary Intratesticular glomus tumor: a rare mesenchymal neoplasm and a diagnostic challenge

Abstract

Abstract Background: Glomus tumors are rare mesenchymal neoplasms of perivascular origin, most commonly found in the dermis or subcutis of distal extremities. Testicular involvement is exceptionally uncommon and poses a diagnostic challenge due to histopathologic similarities with other intratesticular tumors. Case Presentation: We describe an 85-year-old man with a painless, gradually enlarging left testicular mass. Imaging and tumor markers were inconclusive. Radical orchiectomy revealed a well-circumscribed intratesticular lesion. Histology showed uniform round cells with eosinophilic cytoplasm arranged around vascular spaces. Immunohistochemistry demonstrated strong positivity for SMA and negativity for germ cell, stromal, neuroendocrine, and melanocytic markers, confirming the diagnosis of a primary intratesticular glomus tumor. Conclusion: This case underscores the need to consider rare mesenchymal tumors in the differential diagnosis of testicular masses in elderly patients and highlights the pivotal role of immunohistochemistry in establishing an accurate diagnosis.