Anorectal melanoma: Review of 22 consecutive cases

Background/Aims: To evaluate outcome and prognostic factors of patients with anorectal melanoma. Methodology: Twenty-two consecutive patients with anorectal melanoma received operation from 1993 through 2011 were reviewed. The definitions of stage I, II and III are local disease, locoregional lymphadenopathy and metastatic disease, respectively. Results: The patients included 8 men and 14 women, aged from 36 to 83 years (mean, 58.4 years). At the end of the follow-up period, 19 patients died of disease and only 3 patients were alive with disease. Only two patients were alive longer than 5 years after operation. For stage I and II tumors that underwent clinical curative resection (n=17), stage II (p=0.04), tumor size >3cm (p=0.008) and invasion depth to muscle (p=0.021) all showed poorer prognosis in overall survival. Though wide local excision (WLE) were performed in the patients with earlier tumors, there was no statistical difference in overall (p=0.063) and disease-free survival (p=0.333) between WLE and radical surgery. Furthermore, patients with WLE had more chance of local recurrence than radical surgery (6/7 vs. 3/10, p=0.050). Four salvage radical operations could be performed after local recurrence in WLE group. Conclusions: WLE increases the chance of local recurrence more than radical surgery. Care should be taken to avoid microseeding during performed WLE.