I would first like to say I am sorry for not posting a blog in awhile. Life is super busy!
Skin cancer is the most commonly diagnosed cancer in the United States. Basal cell carcinoma and squamous cell carcinoma are two types of skin cancer that are usually less aggressive cancers and cured by excision. Melanoma, however, is quite different.
Approximately 76,000 cases of melanoma will be diagnosed this year with a little over 10,000 people dying from it(1). The estimated number of people with melanoma may be much higher because many superficial melanomas taken care of in the outpatient setting may not be recorded. With the incidence of almost all cancers on the decline, melanoma is an exception. The incidence of melanoma is increasing faster in males than any other cancer. In females it is increasing faster than all cancers except for lung cancer. It is estimated that the lifetime risk of developing a melanoma in females is 1 in 34 and for males 1 in 53.
Risk factors associated with melanoma include a prior history of melanoma, a history of dysplastic nevi, a family history of melanoma and there are also some genetic mutations associated with melanoma. Excessive sun exposure, as well as, artificial tanning beds using UV rays contribute to the development of melanoma.
Melanoma can occur in many different areas. In men, the most common areas are the back and chest. In women, the legs. There are different types of melanoma. Superficial spreading melanoma is the most common type and can grow for years. Approximately 70% of melanomas are this type according to the National Cancer Institute. Nodular melanoma represents approximately 15% of melanomas. It occurs as a “bump” and can grow deep into the layers of the skin quite quickly. Acral-lentiginous melanoma occur more frequently in those with darker skin. The National Cancer Institute estimates that this melanoma represents about 70% of melanomas in African Americans and ~50% in Asians. Acral-lentiginous melanoma can appear on the palms of the hands, soles of the feet and under the nails. Lentigo maligna melanoma is most commonly found on the arms, face, and legs. The areas that see chronic sun exposure. Amelanotic melanoma is a rare type which can be hard to diagnose/spot due to the lack of pigment. Ocular melanoma represents about 3% of melanomas.
It is estimated that 84% of melanomas present at a localized stage, 9 % with regional disease (involvement of the lymph nodes) and 4% with distant disease (1) Those who present with early stage localized melanomas which are 1.0 mm thick or less have an approximate 90% 5-year overall survival rate. Those with a melanoma greater than 1mm in thickness have a 5-year survival between 50-90% . The variability depends on whether or not the melanoma is ulcerated (worse prognostic factor) and the mitotic rate (more mitoses=worse prognosis.) Those with disease which has spread to lymph nodes have a 5-year overall survival varies between 20-70% depending lymph node burden. Those with melanoma that has spread to the organs have a much poorer prognosis. However, with the advent of immunotherapy people are living longer and obtaining remissions for a greater period of time.
Treatment of melanoma includes surgery, chemotherapy, immunotherapy and targeted agents. Cytokines such as interferon alpha and interleukin are sometimes used. Chemotherapy had been the mainstay for metastatic melanoma until the approval of targeted and immunotherapeutic agents. Immunotherapeutic drugs help to stimulate ones own immune system which then “fights” the cancer. These agents include: Yervoy, Opdivo and Keytruda. Targeted agents work by inhibiting cancer cells from growing by blocking signals/pathways. These agents are given if someone is noted to have a specific mutation in the BRAF gene. There is also an oncolytic virus (Imlygic) which is a modified herpes virus. It is injected into melanomas or lymph nodes which then “tricks” the immune system to attack the cancer.
When out and about please don’t forget to use sunscreen. Burns are not healthy and obviously can damage your skin, as well as, cause one of the most deadly cancers. Fortunately, we are making progress against melanoma, however, prevention is the key.
- Siegel RL, Miller KD, Jemel A. Cancer statistics, 2015. CA Cancer J Clin 2015; 65:5-29.