Pathologic staging of melanoma

The American Joint Committee on Cancer (AJCC) recently launched a new staging system for cutaneous melanoma that was based on clinical experience with a large number of patients treated in major centers worldwide. As this system includes various histopathologic parameters of the primary melanoma and of melanoma metastasis, including micrometastases in the sentinel lymph node (SLN), they are discussed here. Special attention is given to ulceration of the primary tumor, because it remains a dominant prognostic parameter in addition to tumor thickness. Molecular markers that may reflect aggressive behavior of the primary melanoma also are described. Finally, pathologic examination of SLNs is addressed with emphasis on the efficacy of various microstaging approaches.