Female primary peritoneal carcinoma (PPC) has the characteristic of diffuse involvement of the peritoneum by papillary carcinoma in the absence of an obvious primary site and grossly normal ovaries, or minimal involvement. It is histologically indistinguishable from primary epithelial ovarian carcinoma (EOC) and is diagnosed in the absence of another identifiable primary. Most reported PPC cases are primary peritoneal serous papillary carcinoma (PPSPC), while peritoneal mixed epithelial carcinoma (MEC) and malignant mixed Mullerian tumor (MMMT) are rarely reported. Germline BRCA1 mutations in 26% of PPSPC patients was detected. BRCA1 mutation carriers had a higher overall incidence of p53 mutations than wildtype BRCA1 case subjects. It is suggested that p53 has a unique role in the development and progression of BRCA1-related PPSPC.