Trends of low-grade serous ovarian carcinoma in the United States

In the United States, ovarian carcinoma remains the most deadly gynecologic malignancy, and approximately 14,000 deaths are projected from the disease in 2017 [1]. Ovarian carcinoma comprises various histologic subtypes based on the cell of origin, with serous carcinoma being the most common subtype. Serous ovarian carcinomas are commonly grouped into 2 types based on histologic characteristics (high-grade and low-grade) [2,3]. Mounting evidence has shown that low-grade serous ovarian carcinoma (LGSOC) has distinct clinical and molecular differences from high-grade serous ovarian carcinoma (HGSOC) [4,5]. Unlike HGSOC, LGSOC is considered a rare tumor and has been understudied due to its low incidence. To date, there have been no population-based reports of LGSOC statistical trends. The objective of our study was to examine the temporal changes in the proportion of LGSOC among women with epithelial ovarian cancer.