Melanoma thickness

Melanoma Thickness

Melanoma thickness, also known as Breslow's depth, is a crucial factor in determining the prognosis and treatment plan for melanoma, a type of skin cancer. It is measured in millimeters (mm) and is used to describe the depth of invasion of the melanoma into the skin.

Definition

Melanoma thickness is defined as the total vertical height of the melanoma, measured from the top of the granular layer (or base of superficial ulceration) to the deepest point of invasion. This measurement is taken from the pathological specimen after the melanoma has been surgically removed.

Importance

The thickness of a melanoma is a key prognostic factor. Thicker melanomas are associated with a higher risk of metastasis (spread to other parts of the body) and a worse overall prognosis. The thickness of the melanoma is also used to guide treatment decisions, including whether surgery, chemotherapy, radiation therapy, or immunotherapy is most appropriate.

Measurement

Melanoma thickness is typically measured using a microscope and a micrometer. The measurement is usually performed by a pathologist who specializes in the diagnosis of diseases by examining cells and tissues.

Staging

The thickness of the melanoma is used in the TNM staging system for melanoma, which also takes into account whether the cancer has spread to the lymph nodes (N) or to other parts of the body (M). The T category in the TNM system is based on the thickness of the melanoma and whether it is ulcerated.

Prognosis

The prognosis for melanoma is generally worse as the thickness increases. However, other factors such as the presence of ulceration, the rate of mitosis (cell division), and the patient's immune response also play a role in determining the prognosis.

See also

• Skin cancer
• Melanoma
• Breslow's depth
• TNM staging