Melanoma is a deadly skin cancer that arises from uncontrolled growth of melanocytes. It is the third most common skin cancer in Australia. Non cancerous growth of melanocytes leads to moles and freckles. Cancerous growth of melanocytes results in melanoma.
50 to 70% of melanoma arise “denovo” – meaning it appears as a new mole. 30 to 50% of melanoma arise from existing moles. Melanomas present in many different shapes, sizes and colors. That is why it is difficult to provide a comprehensive set of warning signs. The first sign of a melanoma is most often an unusual looking freckle or mole.
Melanoma is usually curable when detected and treated early. Dermoscopy during a full skin check is an important tool for the early detection of melanoma. Mole mapping provides a photographic record of the location and size of your moles on the skin surface at that particular point in time. This allows for a comparison your moles in the future to see if they have changed in size or if any new moles have appeared.
Once melanoma has spread deeper into the skin or other parts of the body, it becomes more difficult to treat and can be deadly. If the melanoma cells have reached the dermis (deeper layer of the skin), they may spread to other tissues, to the local lymph nodes or via the blood stream to other organs such as the lungs or brain. This is known as metastatic disease or secondary spread.
|Dermoscopic images of melanomas at Chevron Advanced Medical.|
If you’re worried about a mole, book in for a skin check with us. Images of unusual or suspicious moles will be recorded. If there is a high suspicion for melanoma, a biopsy will be recommended. Biopsies of melanoma are different to that of other skin cancers.
With a suspected melanoma, the whole lesion must be removed with 2mm margins. The lesion is then sent to a Pathologist for diagnosis, where cross sections will be taken and analysed under a microscope. The Pathologist will determine if it is a melanoma and how deep the melanoma is, amongst other information. If it is a superficial melanoma, the scar must be excised again with 5mm to 10mm margins. If it is a deeper melanoma, you may require margins of 20mm to 40mm.
Many people ask why a melanoma must be cut out twice. Put simply, the first excision is a biopsy for histopathological diagnosis. The second excision is the treatment. A melanoma cannot be treated without knowing its histopathology.