The Doctor Found a Suspicious-Looking Lesion. Now What?
If skin cancer is suspected, a skin biopsy is conducted. A biopsy is the only way to confirm the presence of skin cancer. The doctor takes a skin sample from the suspicious area for examination by a lab. The type of biopsy depends on the size and location of the suspicious area:
- Shave Biopsy: a thin layer of the lesion is shaved off
- Punch Biopsy: a special tool rotates and cuts through layers of the skin to take a skin sample
- Incisional Biopsy: takes a deeper skin sample using a surgical knife to cut through the full thickness of the skin, removing only a portion of the tumor
- Excisional Biopsy: removes the entire tumor and is the recommended method when a melanoma is suspected.
Depending on the thickness of the tumor, most biopsies are simple and quick procedures that can be performed in the doctor’s office. The doctor uses a local anesthetic to numb the affected area and uses sutures for all but the shave biopsy. The samples are examined by a pathologist under a microscope to confirm the presence or absence of skin cancer and its type.
Once melanoma is diagnosed, the next step is determining the stage of the disease. Staging determines the extent of a person’s cancer. It includes the determination of the following:
- The thickness of the tumor (Breslow depth)
- Presence or absence of ulceration
- Number of mitoses (dividing cells) within the tumor
- Whether the tumor had spread to the lymph nodes and the number of lymph nodes involved
- Whether the tumor had spread or metastasized to distant parts of the body.
Staging may involve laboratory tests and imaging studies.
Staging is very important. Treatment recommendations and prognoses are based on the stage of the cancer. Stages range from stage 0 to stage IV.
The tumor has not spread and is still limited to the outer layer of the skin (melanoma in situ).
In Stage IA, the tumor is not more than 1 millimeter thick with no ulceration or mitosis.
In Stage IB, the tumor is 1 to 2 millimeters thick with no ulceration.
The tumor has spread to the dermis (deep part of the skin), but has not reached the lymph nodes.
In Stage IIA, the tumor is 1 to 2 millimeters thick with ulceration or 2 to 4 millimeters thick with no ulceration. In Stage IIB, the tumor is 2 to 4 millimeters thick with ulceration or more than 4 millimeters thick with no ulceration. In Stage IIC, the tumor is more than 4 millimeters thick with ulceration.
The tumor has spread to lymph nodes near the affected skin.
In Stage IIIA, the tumor may have spread to as many as three lymph nodes, but the nodes are not enlarged, and the tumor in the lymph nodes can only be seen under a microscope.
In Stage IIIB, the following may happen:
- The tumor is ulcerated and has spread to as many as three lymph nodes but the lymph nodes are not enlarged and the tumor in the lymph nodes can only be see under the microscope OR
- The tumor is not ulcerated and has spread to as many as three lymph nodes but the lymph nodes are enlarged OR
- The tumor has not spread to the lymph nodes, but has produced satellite tumors in the vicinity (within 2 centimeters) of the original melanoma or the tumor cells are in the lymphatic channels nearby.
In Stage IIIC, the tumor has spread to four or more lymph nodes or has clinically evident enlarged lymph nodes.
The tumor has spread to other organs, such as the lung, liver, brain or to lymph nodes far away from the original site.
Read more about the stages of melanoma here.