SkinCancerNet Article
Biopsies Used to Detect the Spread of Melanoma

If a lymph node near the melanoma feels hardened or enlarged, one of the following biopsies is generally performed:

• Fine needle aspiration biopsy – The purpose of a fine needle aspiration (FNA) biopsy is to determine the cause of an enlarged lymph node. This biopsy is performed by inserting a thin needle into the lymph node in question and removing a small amount of tissue so that it can be examined under a microscope to find out if cancer cells are present. This type of biopsy also can be used to collect cells from an internal organ, such as the liver or a lung, when it is suspected that the melanoma has spread to an internal organ.

• Open biopsy – When a lymph node feels abnormally large or hard, the entire lymph node may be surgically removed via an open biopsy. During this procedure, the lymph node is extracted by making a small incision in the skin. An open biopsy provides a larger sample than a fine needle aspiration biopsy, which may reduce the risk of cancer cells being overlooked. For this reason, an open biopsy may be considered if a fine needle aspiration biopsy does not show evidence of melanoma.

If the lymph nodes do not feel enlarged, but the risk that the melanoma may have spread is high, a sentinel lymph node biopsy may be performed:

• Sentinel lymph node biopsy – This surgical procedure is used to stage (determine the extent) melanoma. The procedure begins with the surgeon identifying the first lymph node, known as the "sentinel node," to receive lymph draining from the tumor because this is the node most likely to contain cancer cells. The sentinel node is found by injecting radioactive material and/or dye next to the tumor and tracing the flow of lymph from the site of the melanoma to the local and regional lymph nodes. Once the sentinel node is identified, it is surgically removed and sliced into sections for laboratory analysis to determine if melanoma cells are present. Sometimes, the surgeon will remove two or three nodes. The removed node(s) is usually sent to a pathologist who will examine the tissue to determine if cancer cells are present.

If melanoma is found in a lymph node, a lymph node dissection (removal of the lymph nodes in that area) may be advised. Like any surgical procedure, a lymph node dissection is not without risk. Occasionally, serious side effects occur; some can be permanent. Serious side effects include painful recovery, temporary or permanent numbness in a leg or arm, and lymphedema.

“Lymphedema” is a condition in which excess fluid builds up in the tissue and causes swelling (edema). Swelling typically occurs in an arm or leg; however, it can occur in other parts of the body. This condition can develop when lymph vessels are impaired, damaged, or removed. Elastic sleeves and stockings may help. Sometimes special devices that squeeze the limbs are useful.

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