Large benign chondroid syringoma of the lower limb-an uncommon presentation of a rare disease

Abstract

Chondroid syringoma (CS) is a sporadic skin appendage tumor that manifests as slow-growing, subcutaneous, non-tender, non-ulcerating dermal nodules, most often in the head and neck. The tumor is more common in men, has a biphasic age distribution, and usually attains a size of 0.5 to 3 cm. Larger lesions up to 9 cm in size have been recorded in the literature, with the majority of them containing malignancies. Rare cases of malignant CS have been described, with local recurrence and metastasis. We report a case of an 85-year-old man presenting with complaints of a significantly large swelling in the inner aspect of his right thigh for the past 25 years. Clinical and radiological differential diagnoses of a large uncomplicated dermoid cyst, sebaceous cyst, epidermal inclusion cysts, neurogenic tumours, or myxoid tumours with cystic degeneration were suggested. Under general anaesthesia, the lesion was completely excised with a 1 cm margin of healthy surrounding tissue. The histopathological examination of the complete surgical specimen was consistent with CS. Patient has been on regular follow-up and has shown excellent response to treatment, with no evidence of recurrence, metastasis, or disfigurement. With this paper, we report a case of benign CS in an unusual location, attaining a huge size (>10 cm) and, even then, not turning malignant. We hope to add to the current knowledge on CS, allowing for early and accurate diagnosis and successful disease management.