Abstract: A 63-year-old male presented with a scrotal mass for more than 1 month. The lesion was an oval nodule with relatively clear borders, poor mobility, and blood crusts on the surface. Laboratory examinations showed RPR test was negative, Treponema pallidum antibody (ELISA): 20.33 S/CO, HIV antibody was positive. Histopathological features of the skin lesion were consistent with well-differentiated squamous cell carcinoma. The patient reported occasional perianal discomfort in the recent 8 months. Digital rectal examination revealed a hard mass at the 5-6 o'clock position of the anal canal, and needle biopsy confirmed squamous cell carcinoma. Pelvic magnetic resonance imaging (MRI) with plain and enhanced scans suggested anal canal squamous cell carcinoma, accompanied by enlarged lymph nodes in the bilateral inguinal regions, which were considered metastatic. After multidisciplinary consultation, the patient was transferred to the department of medical oncology for relevant treatment. However, the patient failed to receive regular treatment thereafter and succumbed one year after diagnosis.

Key words: squamous cell carcinoma, scrotal metastasis, anal canal squamous cell carcinoma, HIV, HPV