Surgical therapy for anorectal malignant melanoma

Abstract

Objective To evaluate clinical features, diagnosis and treatment of anorectal malignant melanoma (ARMM).Methods The clinical data of 15 patients of ARMM in our hospital and 18 patients in the First Affiliated Hospital of China Medical University from 1990 to 2010 were reviewed.Twenty-five patients underwent curative surgical resection, 14 patients underwent abdominoperineal excision of the rectum (APR), and 11 patients underwent local excision (LE).Survival analysis was carried out.Fisher's exact test and Log-rank test was used to compare the effects of these two different surgical procedures.Results ARMM had a female predominance, the mean age was 22 -77(54.5 ± 7.6) years.The major clinical signs included hematochezia, anus pain.The misdiagnosis rate was 67% (22/33).The average tumor size was (3.5 ±1.7) cm.Thirty-one petients(94% ,31/33) had ARMM within 5 cm from anus margin.Mean survival time was (14.0 ± 6.5)months.The overall 1-,3-,and 5-year survival rates were 48% ,22% , and 10% , respectively.Local recurrence after curative LE was higher than APR (LE,64% vs APR, 21% , P = 0.049) , The overall 3-year disease-specific survival rates after curative LE was not significantly different from that of APR (LE, 28% vs APR ,31%, x2 = 0.268, P = 0.582).Conclusions Anorectal malignant melanoma has a high rate of misdiagnosis.Radical resection could not prolong the survival time significantly in anorectal malignent melanoma patients. Key words: Melanoma; Anal canal; Rectal neoplasms; Gastrointestinal hemorrhage