Diagnosis

A biopsy is the only certain way of diagnosing melanoma. In a biopsy, the doctor removes an area of the suspicious growth. Biopsies usually are done after the skin is numbed with a local anesthetic so there is almost no pain. Once the tissue sample is removed, a specialist examines it for cancer cells under a microscope.

The type of biopsy depends on the size of the skin growth and its location on the body. Several types of biopsy can be done when the doctor suspects melanoma:

An excisional biopsy excises, or cuts away, the entire growth with a margin of normal surrounding skin. The skin may be stitched together to close the hole. This procedure is more time-consuming and therefore usually needs to be scheduled. Generally, an additional wide local excision of normal surrounding skin will be required if the biopsy is positive. The width of the margin will depend on the thickness of the cancer.

An incisional biopsy, or core biopsy, removes only a sample of the growth, and the resulting hole is closed with stitches. Further treatment is necessary if the microscopic examination reveals cancer cells.

A punch biopsy removes a small, cylindrical shaped sample of skin. It includes the epidermis, dermis, and parts of the underlying tissue. It is done with a surgical tool that looks like a round hollow tube with sharp edges.

A saucerization biopsy removes the entire lesion by cutting under the lesion in a "scoop like" manner. This leaves a large, deep depression in the skin, but can be performed immediately and provides the dermatopathologist with a complete specimen to better analyze the tumors architecture.

A shave biopsy is shaving the top layer of skin (epidermis)Diagnosing many types of skin diseases and in sampling moles when the risk of melanoma is very LOW. May not be thick enough to measure how deeply the melanoma has invaded the skin.

A fine-needle aspiration biopsy is done with a very thin needle and syringe that looks like a hypodermic syringe used for giving injections. It removes a very small sample of tissue. This type of biopsy is not done on a suspicious mole or skin growth. Rather, it is done on other deeper tissue, such as nearby lymph nodes or an internal organ, to see if melanoma has spread.

Lymphoscintigraphy - A tiny dose of radioactive tracer is injected into the skin. The first lymph node which drains the melanoma is called the sentinel node. A gamma camera is used to identify the relevant lymph channels and lymph nodes. it is also called the sentinel node biopsy.

After biopsy, the tissue removed will then be sliced, stained and looked at under a microscope. This comes under histopathology.

to check for metastasis:

blood test

MRI/NMR

Radiology

Ultrasound