Key features of extrauterine pelvic serous tumours (fallopian tube, ovary, and peritoneum)

Ovarian serous carcinoma (OSC) is the most common of the ovarian epithelial malignancies, and accounts for most of the mortality. Traditionally, ovarian cancer has been considered to be one disease; however, it is now apparent that it actually consists of many different entities. OSC can be further segregated into two processes: high-grade serous carcinoma (HGSC) and low-grade serous carcinoma. This classification is supported by molecular changes, morphological appearance, clinical behaviour, and distinct precursor lesions. This review will describe in detail these features of OSC, differential diagnosis, prognosis, and recent challenges to the existing hypotheses regarding the origin of these tumours. Special attention will be paid to HGSC and its relationship with BRCA abnormalities, especially those seen in hereditary breast and ovarian cancer syndrome. Finally, treatment options based on specific molecular targets will be discussed.