Malignant melanoma of the mucous membranes: a review of 119 cases.

Background: Melanomas arising from the mucous membranes lining the respiratory, digestive, and genitourinary tracts are rare. Women are more commonly affected than are men, mainly because there is no male counterpart for vulvovaginal lesions. The mainstay of therapy is surgery, with little current use of adjuvant modalities in primary therapy. These lesions usually are advanced at initial presentation; consequently, the prognosis is poor, with 5-year survivals well below 50% in most series.
Methods: One hundred and nineteen patients with primary mucosal melanoma were reviewed. They represented 1.1% of the 10,393 melanoma patients seen at Duke University between 1970 and 1995. All data were obtained from the patients' clinic charts and computerized databases.
Results: There were 43 tumors arising from the head and neck region, 46 from the urogenital tract, and 30 from the anorectum. A female predominance was observed, with a female-to-male ratio of 2.7:1. All but five of the patients underwent resection with curative intent. Regional or distant metastases, or both, were encountered in 36 patients at the time of presentation. In patients with head and neck and urogenital tumors, local recurrences accounted for most of the treatment failures, whereas systemic recurrences were more common with tumors arising in the anorectum. The age and gender of the patient, anatomic site of origin of the tumor, clinical stage at initial presentation, and ulceration of the primary all clearly affected prognosis. Overall, the probabilities of being alive 1, 5, and 10 years after diagnosis were 80%, 29%, and 15%, respectively.
Conclusions: Widely accepted classification systems are needed so that results from separate institutions can be compared adequately. Multi-institutional trials could help in delineating standardized therapeutic protocols and in establishing the potential roles of emerging modalities in the treatment of this subtype of melanoma.