Glomus tumor of the great toe: An uncommon case report

Abstract

Introduction: Masson’s glomus tumor is a neuromyoarterial hamartomatous proliferation that develops from corpuscules located at the dermal-hypodermal junction, it is a rare but not exceptional benign tumor and it is less frequently reported in the foot. Case presentation: We present a unique case based on its unusual location, clinical presentation (pain being the primary symptom) and its misleading appearance on MRI. Treatment involved surgical excision of the tumor, resulting in a favorable outcome. Histopathological examination of the excised specimen remains crucial for definitive diagnosis, highlighting the importance of considering this unusual location in the differential diagnosis. Discussion: Pathogenesis remains poorly understood, and diagnosis can be difficult. It preferentially affects the hands (75%) and it is subungual in 50% of cases. Diagnosis is based on the clinical triad of sensitivity, pain and intolerance. Advances in high-resolution MRI have improved false negatives, with lesions showing hypo-signal in T1 and hypersignal in T2, with clear contrast between normal tissue and tumor. Diagnostic certainty is provided by histology. After complete removal of the tumor, results are generally considered excellent. In most cases, pain disappears rapidly, and the affected finger or limb returns to normal within three months. Conclusion: Glomus tumors are certainly rare, but not exceptional, and a high degree of suspicion is required when faced with a painful purplish nodule. Usually distal, periungual in location, they can occur anywhere, with sometimes unusual and puzzling localizations.