Implantation metastasis from adenocarcinoma of the colon into a fistula-in-ano: a case report.

Abstract

Viable malignant cells have been isolated from the lumen of bowel and from surgical gloves and instruments after colorectal cancer surgery.1 There are reports of implantation of malignant cells into benign anal lesions during colorectal cancer surgery,2 and of implantation metastasis from colon cancer during colonoscopy and biopsy.3 These reports are, however, rare, and the clinical significance of exfoliated, viable malignant cells from colorectal neoplasms remains unclear. We review a patient with an adenocarcinoma of the left colon and a metastasis in a benign fistula-in-ano, presumably acquired through implantation of viable malignant cells shed from the primary tumour, and discuss the importance of these findings in colorectal cancer surgery.