Case report: thigh hidradenoma masquerading as lipoma

Area of Science:

• Dermatology
• Surgical Pathology
• Oncology

Background:

• Hidradenomas are benign adnexal neoplasms recently classified into eccrine (poroid) and apocrine (clear cell) types.
• While rare, hidradenomas have been associated with recurrence and malignant transformation, necessitating careful management.

Observation:

• A 35-year-old male presented with two painless, slow-growing lumps, clinically suspected to be lipomas.
• One lump, located on the right upper thigh, was initially presumed to be a lipoma.
• Pre-operative assessment revealed firm, mobile, non-tender masses with intact overlying skin and no lymphadenopathy.

Findings:

• Histopathological examination revealed the left shoulder mass to be a lipoma.
• The right upper thigh mass was definitively diagnosed as a hidradenoma.
• This case highlights the diagnostic challenge in differentiating hidradenomas from other benign soft tissue tumors like lipomas based on clinical presentation alone.

Implications:

• Complete surgical excision with clear margins is crucial for managing hidradenomas to prevent recurrence and monitor for malignant potential.
• Accurate histopathological diagnosis is essential for appropriate patient management and follow-up.
• This case underscores the importance of surgical intervention for definitive diagnosis of clinically ambiguous subcutaneous masses.