DOI: 10.36347/sjmcr.2024.v12i01.031

Pages: 119-122

Squamous cell carcinoma, the second most common form of skin cancer, is caused by the cumulative exposure of skin to UV light. It originates from epidermal keratinocytes or adnexal structures (such as eccrine glands or pilosebaceous units). Squamous cell carcinoma (SCC) has several histologic variants, such as clear cell SCC, signet ring SCC, basaloid SCC, desmoplastic SCC, verrucous and pigmented SCC, among others. Although dendritic melanin containing melanocytes can be seen in a variety of epithelial neoplasms, but only 0.01% to 7% of all squamous cell carcinomas (SCC) are pigmented. Most of which have occurred in the oral and ocular mucosa, with relatively few cases to originate in the skin. The main clinical differential diagnosis for pigmented squamous cell carcinoma are pigmented basal cell carcinoma and melanoma. Herein we report a case of 62 year old male who presented with a blue-black growth over the left inguinal region. Routine lab investigations showed no change and no lymphadenopathy was observed. Biopsy of the growth was received and histopathological evaluation revealed pigmented squamous cell carcinoma. Microscopic examination revealed squamous cell carcinoma with numerous dendritic melanophages showing pigmented melanin. Pigmented SCC can be confused with benign and malignant melanocytic neoplasms, pigmented basal cell carcinoma, actinic keratosis, seborrheic keratosis and pigmented bowen’s disease. In conclusion, this case demonstrates that although pigmented squamous cell carcinomas are relatively rare, they should be included in differential diagnosis of pigmented cutaneous lesions and must be distinguished from other tumors with similar histological findings.