Mild clinical phenotype of Kindler syndrome associated with late diagnosis and skin cancer.

Kindler syndrome (KS) is a heritable skin disorder with a complex phenotype consisting of congenital skin blistering, photosensitivity, progressive generalized poikiloderma and extensive skin atrophy. Here we describe 2 siblings with KS, who are, to the best of our knowledge, the oldest patients reported so far in the literature. The diagnosis was established in their seventh and eighth decades of life, and confirmed by mutation analysis. Both patients were homozygous for the recurrent FERMT1 mutation, c.328C→T, p.R110X. Because of a relatively mild course of the disease, mucosal membranes in the eyes and oesophagus being predominantly affected in recent years, they had been treated under other diagnoses, such as scleroderma. Cutaneous precancerous lesions and epithelial skin cancer arose in both siblings after the age of 50 years and were treated in an early stage. Taken together, we describe the natural course of KS, the morphological abnormalities occurring in the skin of older KS patients, we discuss the differential diagnosis and the association between KS and squamous cell carcinoma.