Bloch–Sulzberger syndrome in the practice of a pediatric oncologist

Bloch–Sulzberger syndrome (SBS, incontinentia pigmenti) is a rare genodermatosis associated with pathogenic variants of the IKBKG (NEMO) gene localized on the long arm of the X chromosome (Xq28). Among the clinical manifestations, the most common are typical stageby-stage skin lesions, the development of ophthalmological and neurological pathology, as well as abnormalities of teeth, hair and nails. Cancer in SBS is extremely rare and known by sporadic cases of retinoblastoma, Wilms tumor, leukemia and skin cancer. We performed clinical and genetic investigation of two families with SBS. In both cases, the deletion of the 4–10 exons of the IKBKG gene was transmitted through the maternal line. In the first case, ophthalmological changes were suspicious of retinoblastoma, but further examination revealed vitreous fibrosis and retinal detachment. In the second case, one of the three sisters was diagnosed with squamous cell skin carcinoma at the age of 11. These clinical observations and the literature review, make necessary to increase the awareness of pediatric oncologists about SBS due to the possible association of this syndrome with an oncogenic risk.