Familial atypical multiple mole melanoma syndrome (FAMMM syndrome) is an inherited condition characterized by the presence of multiple moles. Atypical moles, also called dysplastic nevi, are benign but are associated with an increased risk of melanoma. They can occur sporadically (with no other cases in a family), but are a symptom of FAMMM when multiple family members are affected. FAMMM syndrome may also increase the risk of pancreatic cancer in addition to melanoma. FAMMM syndrome is marked by:
- one or more 1st or 2nd degree relatives (parent, sibling, child, grandparent, grandchild, aunt, or uncle) with malignant melanoma;
- many moles, some of which are atypical (asymmetrical, raised, or different shades of color) and often of different sizes; and
- moles that have specific features when examined under a microscope.
may be caused by mutations in the CDKN2A gene (in about 40% of cases) or CDK4 gene (in very rare cases). However, in about 60% of cases, the cause is unknown. Inheritance is autosomal dominant. Treatment for FAMMM syndrome typically involves surgery. Family members of people with this condition should have surveillance at periodic intervals for melanoma.