Peritoneal Serous Borderline Tumour with Ultra-Mutated NGS Profile Including POLE E, BRAF, RB1, HER2 and P53 Mutations : A Case Report.

Background: Serous borderline tumors of the peritoneum are rare low-grade epithelial proliferation with a tubal-type differentiation occurring in the pelvis or abdomen without underlying tissue invasion that resemble to ovarian serous borderline tumors but by definition without ovrian or tubal involvement. To date, the mutation status in molecular biology of these tumours remains largely unknown.Case presentation: Here we describe the case of a borderline peritoneal serous tumour which occurred in a 48 year old patient in whom an analysis of the mutation status by NGS technique identified a ultra-mutated profile including POLE E, BRAF, RB1, HER2 and p53 mutations.Conclusions: To the best of our knowledge, this particular mutation status has never been described in this type of tumour. It could represent an early event with transient mutations, most of them will not fixate on the genome.