This condition has received many names over the years including dysplastic nevus syndrome, atypical mole syndrome, B-K mole syndrome, and the familial atypical multiple mole melanoma (FAMMM) syndrome. Affected patients have a personal and/or family history of melanoma and multiple, clinically atypical nevi. Patients often have many nevi, e.g., 100, and often have them in unusual places, e.g., tops of the feet. See also Clark nevus.
Some kindreds with the FAMMM syndrome have a CDKN2A mutation on chromosome 9 and are at increased risk for pancreatic and other systemic cancers. See genetics and melanoma.
Many nevi are often present and many of those exhibit several if not all of the ABCDE criteria. Patients routinely have over 50 and some over 100 nevi. Nevi may occur virtually anywhere including the feet, buttocks, and scalp.
Should a patient undergo genetic testing? There is no uniformly accepted criteria. Some use the rule of 3s, i.e. the melanoma patient who has 2 family members with either melanoma or pancreatic cancer should be referred for genetic testing.
The patient must be thoroughly and repeatedly educated on their high risk for melanoma, the ABCDE's, the need for sun protection, monthly need for self mole check, and the vital importance of seeing the dermatologist regularly. Any lesion that has 2 of the ABCDE criteria should be removed entirely for histologic examination. Some dermatologists find great value in using total body photography (TBP) to aid the examinations. TBP helps decrease worry in high-risk patients [JAMA Derm 2015;151;137].