Isolated Subcutaneous Sarcoidosis (Darier–Roussy Disease) Without Systemic Involvement: Diagnostic Challenge and Remission Following Intralesional Therapy

Subcutaneous sarcoidosis (Darier–Roussy disease) is a rare variant of cutaneous sarcoidosis characterized by painless subcutaneous nodules. We present the case of a 55-year-old woman with a firm, nontender mass overlying her right triceps region, initially misdiagnosed as cellulitis. Biopsy revealed a noncaseating granuloma consistent with subcutaneous sarcoidosis. Extensive systemic work-up was unremarkable, confirming isolated disease. The lesion resolved within 6 months following 2 intralesional corticosteroid injections administered 2 months apart, with no recurrence over 4 years. This case highlights the diagnostic challenges of subcutaneous sarcoidosis and the importance of histopathologic confirmation and multidisciplinary evaluation, even in the absence of systemic symptoms.