Tissue and tumor mosaicism of the myotonin protein kinase gene trinucleotide repeat in a patient with multiple basal cell carcinomas associated with myotonic dystrophy.

We describe the third case (to our knowledge) of multiple basal cell carcinoma associated with myotonic dystrophy and carry out a genetic study of the tumor comparing it with healthy skin. We consider that our results show that this association might be not a purely random phenomenon and that the particular genetic characteristics of this disorder might have a role in the pathogenesis of the tumor.