Epidemiology and Outcome of Squamous Cell Carcinoma in Epidermolysis Bullosa in Australia and New Zealand

: We investigate the epidemiology and outcomes of squamous cell carcinoma (SCC) in recessive dystrophic epidermolysis bullosa (RDEB) from the Australasian EB registry cohort. Seventeen out of 49 (34.6%) RDEB patients developed at least one SCC. Data detailing SCC was obtainable from 16/17 RDEB-SCC patients. A total number of 161 primary SCCs occurred in 16 RDEB-SCC patients with a mean of 10 SCCs per person. The earliest age of first SCC development was 16 years. Eleven out of 16 RDEB-SCC patients eventually developed metastatic SCCs. The majority of the tumours were well and moderately differentiated. The cumulative risk of SCC development by age 35 was 76.1% for RDEB-Generalized Severe (RDEB-GS) and 10% for RDEB-Generalized Intermediate (RDEB-GI). Amongst those who developed SCCs, their median time to death after first SCC was 5 years for RDEB-GI and 4 years for RDEB-GS. This is the first retrospective study of RDEB-SCC in Australasia.