Gangrene Secondary to Perineal Invasion by Rectal Cancer: A Case Report and Literature Review.

Colorectal cancer usually metastasizes through lymphatic, blood, and intraperitoneal implantation. However, rectal cancer combined with perineal invasion after treated with chemotherapy is very rare. The present case study is of a 53-year-old male patient with a history of rectal cancer who developed a recto-perineal fistula with redness, swelling, and pain in the scrotum after repeated chemotherapy. After a CT examination and investigative observation, the patient was diagnosed with a recto-perineal fistula. After surgical debridement and postoperative implant treatment, the patient's infection resolved, and the skin-grafting treatment worked well. The present case called attention to rectal cancer after being treated with chemotherapy.