Staging is a process to determine the extent to which cancer may have spread. Dr. Patel, can you tell us about the stages of melanoma?
Sure, Dr. Mayzik. Generally, cancer can spread in three ways: through tissue, the lymph system, and the blood. When cancer spreads through the lymph system or the blood, it can travel to parts of the body that are quite distant from the original cancer site. This is called metastasis.
Since melanoma has a higher risk of metastasizing, staging is done to learn how dense or thick the growth or tumor is, how deeply it has affected the skin, whether the cancer has spread to other parts of the body, and whether the tumor is ulcerated, meaning it has broken through the skin.
Stage 0 melanoma is also called melanoma in situ. In this stage, abnormal melanocytes, which may become cancer and spread into nearby normal tissue, are found in the epidermis only.
In stage I and stage II melanoma, the cancer has not spread to the lymph nodes or other parts of the body.
These stages may be subdivided into A, B, or C, depending on the primary tumor’s depth, as well as the presence or absence of ulceration.
Stage III melanoma means the cancer has spread into the lymph nodes. In stage IV, melanoma has spread to distant organs or other parts of the body.