Definition

A group of tumor cells in an area near the primary (original) tumor. In melanoma, satellite tumors occur within 2 centimeters of the primary tumor, on or under the skin, and can be seen without a microscope. Satellite tumors may also be found in other types of cancer, including cancers of the breast, lung, liver, and brain. Having a satellite tumor is a sign that the cancer has spread from where it first formed.