The prognosis depends on whether the malignant melanoma is localized, regional, or metastatic at the time of diagnosis. 83.7% are diagnosed at the local stage and the 5-year survival for localized malignant melanoma is 98.5%. The overall 5-year survival rate for patients with malignant melanoma during the period 2007-2013 was 91.7%.
The number of deaths is highest among people aged 75-84.
Death rates have been stable over 2005-2014. In 2014, there were an estimated 1,169,351 people living with malignant melanoma in the United States and in 2017 there are an estimated 9,730 people will die of this disease (1).
Prognostic factors for skin melanoma
- Vertical thickness of primary tumor. The Breslow thickness is the most important prognostic parameter as long as metastases are not present at the time of diagnosis.
- Ulceration. The prognosis is worse in cases of ulceration (9,10).
- Mitotic rate. Tumor cell proliferation measured by mitotic rate is an independent prognostic factor for the thinnest melanomas. The presence of > 1 mitosis / mm ² predicts a poorer prognosis.
- Regional and metastatic disease. Metastases to regional lymph nodes will lead to a drastic fall in five year survival. The number of metastatic glands greatly influences the prognosis. For distant metastases, the chance of survival is < 10%. The prognosis is best if the metastatic spreading is to the skin, subcutanous tissue, lymph nodes, and lungs. The prognosis is the poorest in cases of spreading to the brain and liver.
Prognostic factors for malignant melanoma in mucous membranes
- Tumor thickness. This is the most important prognostic indicator. Lesions with thickness < 0.75 mm metastases are rare. Lesions with thickness > 5 mm have a poor prognosis.
- Vessel infiltration. This is a significant prognostic factor and predicts local relapse, regional metastases, and distant metastases, as well as disease-free survival.