A new American Joint Committee on Cancer staging system for cutaneous melanoma
The Melanoma Staging Committee of the AJCC has proposed major revisions of the melanoma TNM and stage grouping criteria. The committee members represent most of the major cooperative groups and cancer centers worldwide with a special interest in melanoma; the committee also collectively has had clinical experience with over 40,000 patients. The new staging system better reflects independent prognostic factors that are used in clinical trials and in reporting the outcomes of various melanoma treatment modalities. Major revisions include 1) melanoma thickness and ulceration, but not level of invasion, to be used in the T classification; 2) the number of metastatic lymph nodes, rather than their gross dimensions, the delineation of microscopic versus macroscopic lymph node metastases, and presence of ulceration of the primary melanoma to be used in the N classification; 3) the site of distant metastases and the presence of elevated serum LDH, to be used in the M classification; 4) an upstaging of all patients with Stage I,II, and III disease when a primary melanoma is ulcerated; 5) a merging of satellite metastases around a primary melanoma and in-transit metastases into a single staging entity that is grouped into Stage III disease; and 6) a new convention for defining clinical and pathologic staging so as to take into account the new staging information gained from intraoperative lymphatic mapping and sentinel lymph node biopsy. The AJC Melanoma Staging Committee invites comments and suggestions regarding this proposed staging system before a final recommendation is made.