Metastatic Seeding of Abdominal Wall After Drainage of Perforated Colorectal Cancer in a Presumed Complicated Diverticular Disease.

A 37-year-old male presented multiple times for abdominal pain with a persistent diverticular abscess on imaging that was managed previously with antibiotics and percutaneous drainages. Due to unrelenting abdominal pain and multiple presentations of unresolved acute complicated diverticulitis, the patient underwent an exploratory laparotomy. A colonic mass was discovered, and the patient had a colonic resection. Pathology revealed invasive transverse colonic adenocarcinoma with perforation and involvement of the stomach. Imaging showed no distant metastatic disease and chemotherapy was started. Months after treatment, the patient developed skin lesions and a palpable mass at the previous drain site. Biopsy showed metastatic adenocarcinoma consistent with colonic origin. Colonic adenocarcinoma with metastasis to the abdominal wall after drainage of presumed diverticular abscess is rare. Clinicians should consider malignancy when a patient has a recurrent diverticular abscess that has failed medical management and multiple drainages. Clinicians should remain vigilant of the risk of seeding colonic adenocarcinoma to the abdominal wall when repeated drainage is performed.