Sub-type Specific Genomic Mutations in sBOTs

Introduction Borderline Ovarian Tumors (BOTs) behave indolently in the vast majority of cases and the prognosis is usually favorable. There is more evidence that two subtypes of BOTs represent a higher risk of recurrence or even progression to an invasive ovarian cancer. In case of a presentation with a micro-papillary grow pattern or when invasive implants are diagnosed the prognosis tend to be less favorable. Genome sequencing in ovarian cancer helped to differentiate two different pathways in the carcinogenesis. Low grade serous carcinomas evolving from adenofibromas or borderline tumors over non-invasive micropapillary serous borderline tumors to invasive micropapillary serous carcinoma, show frequent mutations in the Kirsten Rat Sarcoma gene (KRAS), B-Raf Kinase gene(BRAF), Erb-B2 Receptor Tyrosine Kinase 2 gene (ERBB2), Phosphatase and Tensin homolog gene (PTEN), Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha gene (PIK3CA) and Catenin Beta 1 gene (CTNNB1). This pathway is called Type I and is characterized by a slow step-wise process. These low-grade invasive tumors are indolent and are known with a better outcome than high-grade invasive tumors. In contrast the Type II pathway development of invasive tumors is rapid and vast majority of tumors show a Tumor Protein p53 (TP53) mutation and loss of Breast Cancer type 1 susceptibility protein (BRCA1). The aim of this study is to identify different origin in carcinogenesis between serous borderline ovarian tumors presenting a. without implants, b. with non-invasive implants, c. with invasive implants and d. with micropapillary pattern. The presence of specific mutations could suggest for a more aggressive primary treatment if a higher risk of recurrence can be expected.