Ben Switzer, DO, MHSA, MS
Assistant Professor of Oncology, Department of Medicine
Diagnosing Melanoma: A Detailed Process
Melanoma diagnosis often begins after the removal and pathological examination of a suspicious lesion or mole, which is then confirmed as cancerous. This critical step, known as a biopsy, entails either partially or completely excising the lesion or mole for microscopic investigation, at which point, if melanoma is identified, the lesion or mole is termed a primary tumor.
The discovery of melanoma varies greatly among patients. It may be identified by a healthcare professional-such as a dermatologist during a skin examination, an ophthalmologist during an eye examination, or a general practitioner during a routine checkup-or by patients themselves who notice changes in a mole or the emergence of a new lesion. In some cases, melanoma is spotted by a spouse, parent, friend, child, or even a hairstylist.
The critical next step upon spotting a suspicious mole or lesion is consulting a healthcare provider experienced with melanoma. They can then assess the lesion, remove it if melanoma is suspected, and conduct a comprehensive skin examination for any other suspicious lesions.
However, melanoma is sometimes detected only after it has spread. Rarely, a skin biopsy might reveal metastasized melanoma instead of a primary tumor. In other scenarios, metastasized melanoma is discovered through an X-ray, scan, or other diagnostic methods. This text focuses on diagnosing a primary tumor melanoma through skin biopsy to explain a more common diagnostic progression.
The Comprehensive Skin Examination
A thorough skin examination by your healthcare provider, conducted without clothing to inspect all skin areas, is crucial. Special attention is given to areas you've indicated as changed or suspicious, and your family history of melanoma is discussed. Your provider may use a dermatoscope to closely examine suspicious lesions or moles, evaluating them based on the 'ABCDE' criteria:
- Asymmetry - whether one half of the lesion/mole differs from the other.
- Border - the presence of irregular or scalloped edges.
- Color - the variation of shades or colors within the lesion/mole.
- Diameter - whether the lesion/mole is larger than 6 mm.
- Evolving - any changes in the lesion/mole over time, including size, shape, color, bleeding, or itching.
Biopsy Procedure
Should melanoma be suspected, your healthcare provider will perform a skin biopsy. This procedure usually involves removing a portion or the entirety of the suspicious lesion/mole for pathological examination by a pathologist or a dermatopathologist-specialists in diagnosing diseases through the microscopic examination of cells, tissues, and organs, with dermatopathologists focusing on skin pathology.
Understanding the Diagnosis
A pathologist or dermatopathologist will scrutinize the tissue sample to detect the presence of melanoma cells. Their findings are documented in a pathology report sent to your physician, who will then discuss the results with you. If melanoma is confirmed, the report will specify the melanoma's stage, typically Stage 0, Stage I, or Stage II, based on the biopsy, since a tissue sample cannot show lymph node involvement (Stage III) or distant metastases (Stage IV). If your pathology report, medical history, or physical examination suggests potential spread to lymph nodes or distant sites, your doctor might recommend further tests to ascertain if the melanoma has advanced to Stage III or IV.