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Final version of 2009 AJCC melanoma staging and classification
Charles M Balch1, Jeffrey E Gershenwald, Seng-Jaw Soong
1Department of Surgery, Oncology and Dermatology, Johns Hopkins Medical Institutions, 600 N. Wolfe St, Osler 624, Baltimore, MD, 21287, USA. balchch@jhmi.edu
Summary
The American Joint Committee on Cancer (AJCC) melanoma staging system was revised using a large database. Key changes include using mitotic rate over invasion level for T1b melanomas and clarifying criteria for regional and distant metastases.
Area of Science:
- Oncology
- Dermatology
Background:
- Cutaneous melanoma staging is crucial for prognosis and treatment.
- The American Joint Committee on Cancer (AJCC) staging system requires periodic updates based on new data.
Purpose of the Study:
- To revise the AJCC staging system for cutaneous melanoma.
- To incorporate data from an expanded AJCC Melanoma Staging Database.
Main Methods:
- Multivariate analysis of 30,946 patients with stages I-III melanoma and 7,972 patients with stage IV melanoma.
- Revision of TNM classifications and stage grouping criteria.
Main Results:
- For localized melanoma, tumor thickness, mitotic rate (mitoses/mm²), and ulceration are key prognostic factors.
- Mitotic rate replaces invasion level for T1b melanoma definition.
- N category for regional metastases considers number of nodes, tumor burden, and ulceration; microscopic nodal metastases are Stage III.
- M category for distant metastases considers metastatic site and serum lactate dehydrogenase levels.
Conclusions:
- Evidence-based revisions to the AJCC melanoma staging system enhance understanding of the disease.
- These revisions are incorporated into the seventh edition (2009) of the AJCC Cancer Staging Manual.
