09 Aug Diagnosis: Melanoma and Other Skin Cancers
There are several different routes to being diagnosed with melanoma. The first step is generally a physical screening, during which your physician will check your skin for moles or other abnormalities and ask questions, such as if there have been any changes in your skin or moles, or the length of time you have had certain moles. In order to accurately answer these questions, it helps to self-examine your skin monthly to keep track of any changes; more information on moles and skin self-examinations can be found here. During the appointment, your physician will likely also ask you about your medical history, if you have a history of getting sunburned or using tanning beds, whether there has been skin cancer in your family, and other similar inquiries.
If the physician finds something of concern on your skin, he may perform additional tests. These tests are outlined below in some detail.
Dermoscopy is the process of using a hand-held microscope, computer imaging or a dermatoscope to more closely examine a lesion. Your physician might apply mineral oil to the lesion to lessen light reflection on the skin.
The biopsy is a process in which cells or tissue of concern are removed from the body to be tested for cancer cells. Depending on the size and location of the lesion, either an incisional or excisional biopsy will be performed. An incisional biopsy is the removal of part of the lesion because the location or size of the lesion renders a complete removal impossible. An excisional biopsy is the removal of the entire lesion, plus a small margin of surrounding normal tissue.
Biopsies are also often performed on the lymph nodes surrounding the cancer site, given that cancerous fluid is likely to move through them. The closest lymph node(s) to the cancer site is the sentinel node(s). As the most likely place a cancer will first spread, the sentinel node(s) and sentinel node biopsies (SLNB) are important for melanoma staging and prognosis. SLNB is often used when clinical evidence that cancer has spread to other lymph nodes is lacking. SLNB will generally not be performed in cases where the patient has stage 1A melanoma, melanoma in situ, metastatic melanoma, locally advanced melanoma that has spread to a lymph node, or has already had surgery on a lymph node. Ideally, an SLNB will be performed at the same time as another surgery. If cancer cells are present in the sentinel lymph node, it is likely that some of the lymph node biopsy procedures outlined below will be performed. If no cancer cells are present, it is unlikely that cancer has spread to the lymph nodes.
There are several other forms of lymph node related biopsy. A surgical lymph node biopsy involves the surgical removal of lymph nodes to see if they contain cancer cells. This is usually preceded by a fine needle aspiration (FNA) biopsy, in which fluid from a lymph node is removed and tested. There is also the lymph node dissection, in which all of the lymph nodes surrounding the cancer site are removed. This surgery is usually performed if the cancer has metastasized to the lymph nodes.
During your treatments, you may receive other tests to determine whether your melanoma has metastasized to other places in the body. These include x-rays, ultrasounds, blood tests, CT scans, or MRIs.
Thank you for reading; we hope this post answers some of the questions you might have had about the diagnosis procedures for melanoma and other skin cancers. If you would like more information, you can look at one of our sources below. While methods of diagnosing skin cancer are relatively universal, be aware that not every website we source content from is Canadian.
“About Melanoma: Signs and Symptoms of Melanoma”. NCCN Guidelines for Patients: Melanoma. 2014: National Comprehensive Cancer Network Foundation.
“Diagnosing Melanoma”. Canadian Cancer Society.