Unusual 'recurrence' sites for colorectal cancer.

Five patients are reported. Four underwent major 'curative' restorative colorectal resections and developed perineal 'recurrence', 2 developed 'recurrence' in the distal ends of previously identified fistulae in ano and 2 developed 'recurrence' at the site of a previously performed haemorrhoidectomy. The fifth patient developed metastasis to a fistula track prior to surgical intervention. The danger of implantation of exfoliated tumour cells in patients with distally situated 'raw' mucosal sites is recognized and anorectal procedures should not be performed prior to resection. Minor anorectal procedures should not be performed at the same time as colorectal resections for carcinoma in these patients either. Some 'recurrences', such as those described in this paper, may be inevitable and in fact really represent preoperative metastases. Routine flexible sigmoidoscopy prior to the performance of any anorectal procedure might identify patients at risk of such 'recurrences' but this may not be cost-effective.