There are a number of subtypes of melanoma. The two most common are superficial spreading melanoma (SSM) and nodular melanoma. About 70 percent of melanoma cases are SSM and it is the most common type of cutaneous melanoma occurring in light-skinned people. It starts as a deeply pigmented macule or plaque that develops into a cancerous lesion. Nodular melanoma occurs in 15 percent of all melanomas and starts as a uniform nodule. “Rapid growth is also a hallmark of nodular melanoma” (4)
Staging for melanoma is the process of determining how widespread the cancer has become.
Melanoma is staged in two methods: clinical staging and pathologic staging. Clinical staging is based on physical exam, results of a biopsy and other imaging tests. Pathologic staging combines clinical staging results with those of biopsies of lymph nodes or any organs. (2)
Staging for melanoma is expressed using the same classification as other cancers with the TNM.
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