Ovarian Cancer Subtyping to Understand Risk, Treatment, Survival, and Racial/Ethnic Disparities

Ovarian cancer is the deadliest gynecologic cancer, with a five-year survival of only 47%. Treatment has remained consistent over the last several decades, using a "one size fits all" approach for the various histotypes, with minimal improvement in outcomes. Doherty and colleagues have focused on deciphering heterogeneity in ovarian cancer tumors, as a guide to the understanding of risk, treatment, survival, and racial/ethnic disparities. In a definitive paper on this topic, they used data from >28,000 cases in the Surveillance, Epidemiology, and End Results (SEER) program. The group found that histotypes, as defined by the new WHO guidelines, are associated with apparent differences in survival in the U.S. population. The most common and lethal histotype, high grade serous ovarian cancer (HGSC), is also highly variable. As part of an international team of investigators, Doherty and colleagues have also developed a new clinical test, PrOTYPE (Predictor of high-grade serous Ovarian carcinoma molecular subTYPE), to classify HGSC into one of four known molecular subtypes associated with differential survival, and distinct biological features believed to respond differently to treatment options. PrOTYPE allows the classification of an individual patient's tumor in real-time and has applications for research studies and clinical trials. They are also examining epidemiologic features associated with each histotype and HGSC subtype, and whether the prevalence and features of the subtypes are linked to racial/ethnic disparities in ovarian cancer outcomes.