Unusual Cancers of Childhood (PDQ®): Treatment - Patient Information [NCI] - Other Rare Unusual Cancers of Childhood
Tests to diagnose and stage melanoma may include the following:
- Physical exam and history.
- X-ray of the chest.
- CT scan.
- PET scan.
See the General Information section for a description of these tests and procedures.
Other tests and procedures used to diagnose melanoma include the following:
- Skin exam: A doctor or nurse checks the skin for bumps or spots that look abnormal in color, size, shape, or texture.
- Biopsy: All or part of the abnormal-looking growth is cut from the skin and viewed under a microscope by a pathologist to see if cancer cells are present. There are 4 main types of skin biopsies:
- Shave biopsy: A sterile razor blade is used to "shave-off" the abnormal-looking growth.
- Punch biopsy: A special instrument called a punch or a trephine is used to remove a circle of tissue from the abnormal-looking growth.
- Excisional biopsy: A scalpel is used to remove the entire growth.
- Wide local excision: A scalpel is used to remove some of the normal tissue around the area where melanoma was found, to check for cancer cells. Skin grafting may be needed to cover the area where tissue was removed.
- Sentinel lymph node biopsy: The removal of the sentinel lymph node during surgery. The sentinel lymph node is the first lymph node to receive lymphatic drainage from a tumor. It is the first lymph node the cancer is likely to spread to from the tumor. A radioactive substance and/or blue dye is injected near the tumor. The substance or dye flows through the lymph ducts to the lymph nodes. The first lymph node to receive the substance or dye is removed. A pathologist views the tissue under a microscope to look for cancer cells. If cancer cells are not found, it may not be necessary to remove more lymph nodes.
- Lymph node dissection: A surgical procedure in which lymph nodes are removed and a sample of tissue is checked under a microscope for signs of cancer. For a regional lymph node dissection, some of the lymph nodes in the tumor area are removed. For a radical lymph node dissection, most or all of the lymph nodes in the tumor area are removed. This procedure is also called a lymphadenectomy.
- FISH (fluorescence in situ hybridization): A laboratory test used to look at genes or chromosomes in cells and tissues. Pieces of DNA that contain a fluorescent dye are made in the laboratory and added to cells or tissues on a glass slide. When these pieces of DNA attach to certain genes or areas of chromosomes on the slide, they light up when viewed under a microscope with a special light. This test is done to tell the difference between melanoma and melanocytic tumors of unknown metastatic potential (MELTUMP).
- Cytogenetic analysis: A laboratory test in which cells in a sample of tissue are viewed under a microscope to look for certain changes in the chromosomes.