Melanoma
see Primary melanocytic neoplasm.
see Melanoma brain metastases.
see Melanoma spine metastases.
Melanoma (Listeni/ˌmɛləˈnoʊmə/; from Greek μέλας melas, “dark”) is a type of skin cancer which forms from melanocytes (pigment-containing cells in the skin).
Although tumorigenesis of melanoma remains poorly understood, recent advances in gene expression profiling have revealed molecular mechanisms of this deadly disease. In addition, high-throughput gene expression has many advantages over techniques in cancer transcriptomic studies and has led to the discovery of numerous diagnostic, prognostic, and therapeutic targets.
Melanomas are characterized pathologically by epithelioid to spindled cells arranged in fascicles or sheets with significant cellularity, pleomorphism, and nuclear atypia. They have elevated mitotic rate and mitotic labeling index (MIB-1/Ki67 labeling). Immunohistochemically, they typically stain for S-100 protein and HMB-45 but not for EMA.
When compared to primary melanocytic lesions of the CNS, metastatic melanomas were characterized by BRAF gene mutations and wild-type GNAQ and GNA11 genes 1).
Epidemiology
In women, the most common site is the legs, and melanomas in men are most common on the back. It is particularly common among Caucasians, especially northern Europeans and northwestern Europeans, living in sunny climates. There are higher rates in Oceania, North America, Europe, Southern Africa, and Latin America.
This geographic pattern reflects the primary cause, ultraviolet light (UV) exposure in conjunction with the amount of skin pigmentation in the population.
Melanocytes produce the dark pigment, melanin, which is responsible for the color of skin. These cells predominantly occur in skin, but are also found in other parts of the body, including the bowel and the eye (see uveal melanoma). Melanoma can originate in any part of the body that contains melanocytes.
The treatment includes surgical removal of the tumor. If melanoma is found early, while it is still small and thin, and if it is completely removed, then the chance of cure is high. The likelihood that the melanoma will come back or spread depends on how deeply it has gone into the layers of the skin. For melanomas that come back or spread, treatments include chemo- and immunotherapy, or radiation therapy. Five year survival rates in the United States are on average 91%.
Melanoma is less common than other skin cancers. However, it is much more dangerous if it is not found in the early stages. It causes the majority (75%) of deaths related to skin cancer.
Globally, in 2012, melanoma occurred in 232,000 people and resulted in 55,000 deaths.
Australia and New Zealand have the highest rates of melanoma in the world.
It has become more common in the last 20 years in areas that are mostly Caucasian.
Perineural spread is a well-known mechanism of dissemination of head and neck malignancies. There are few reports of melanoma involving the brachial plexus in the literature. To their knowledge, Restrepo et al. report the first known case of perineural spread of malignant melanoma to the brachial plexus. Clinicoradiological and anatomopathological correlation is presented, highlighting the importance of peripheral nerve communications in perineural spread 2).
Classification
BRAF V600 mutation in melanoma
In 1999, Brat et al published their description and classification of these lesions.
see Malignant melanoma…
Treatment
The treatment includes surgical removal of the tumor.
Books
Brain Metastases from Primary Tumors, Volume 3: Epidemiology, Biology, and Therapy of Melanoma and Other Cancers
The book discusses the link between primary tumors and brain metastases of melanoma, including molecular mechanisms, treatment options, prognosis, and general applications. Comprehensive chapters discuss systemic therapy, integrin inhibitors, stereotaxic radiosurgery, and more, making this book a great resource for neurooncologists, neurosurgeons, neurologists, and cancer researchers.
Presents the only comprehensive reference detailing the link between primary cancers and brain metastases in melanoma
Aids the target audience in discussing various treatment options for patients with brain metastases from melanoma
Edited work with chapters authored by leaders in the field around the globe – the broadest, most expert coverage available