Prognosis and staging in melanoma.

For patients who have primary cutaneous melanoma, tumor thickness is the most significant prognostic factor. In addition, other factors, including Clark's level (In thin melanoma), anatomic site of tumor, tumor histology (especially ulceration), patient age, and gender all have prognostic significance. With regional lymph node metastases, the number of lymph nodes involved, and secondarily the presence of nodal capsular invasion, are the most important prognostic features. In distant metastatic disease, the number (I versus > I) and site of metastatic lesions, were the most important prognostic variables. Staging of primary melanoma with extensive radiological imaging is not cost effective, but patients who have positive lymph nodes or other sites of metastases should have such studies to include magnetic resonance imaging of the brain. The follow-up of patients with high risk or advanced melanoma should reflect the fact that metastatic disease is largely incurable, and most recurrences are discovered on history, physical examination, and chest x-ray. Elaborate laboratory and imaging studies should only be used in patients for whom more extensive disease is suggested by simple and limited evaluation.