Huge perianal basal cell carcinoma

Introduction: Basal cell carcinoma (BCC) is a common skin malignancy, but perianal BCC is rare and usually small. Here, we present a patient with a condyloma-like huge perianal BCC. Patient concerns: A 60-year-old Chinese man presented with a progressively growing perianal mass that had been growing for 8 years. The diameter of the perianal mass was ultimately up to 7 cm, accompanied by intermittent bleeding. Diagnosis: Histopathological evaluation of the punch biopsy specimen revealed BCC. Interventions: Total excision of the mass and transverse colostomy was performed. The postoperative pathological result was BCC, but part of the specimen's incisal margin was infiltrated by cancer. Therefore, after a month of recovery, local radiotherapy was started, and the wound healed completely. Stoma reversal was performed 4 months after the surgery. Outcomes: Postoperative anal function was satisfactory. The patient was asymptomatic and showed no signs of BCC recurrence one year after surgery. Conclusion: We present a case of isolated large perianal BCC in a patient with no known risk factor. As for huge perianal BCC, local wide resection is the preferred treatment. If the wound is large and close to the anus, transverse colostomy is needed. However, it is difficult to ensure a safe incisal margin because of the large size of the tumor; therefore, radiotherapy is also required.