The increasing incidence of granulosa cell tumors in the United States: what factors are responsible?

Abstract

Objectives: Although the incidence of ovarian cancer has decreased over the past several years, it is unclear if this finding is represented in the uncommon histologic types. As such, we investigated the incidence and trends of granulosa cell tumors of the ovary in the United States. Methods: Data were extracted from the United States Cancer Statistics, 2001-2016. Trends in the incidence was analyzed by SEER*Stat 8.3.8. Chi-square tests were used for statistical analysis. Results: Of 5,531 patients with granulosa cell tumors, 60.7% were White, 23.9% Black, 11.2% Hispanic, and 2.6% Asian. Local, regional, and distant, and unknown stages represented 52.7%, 26.5%, 13.1%, and 7.7% of the study population. The annual percent change in incidence (APC) of White individuals was 2.15% (p<0.01) compared to 2.59% in Black patients (p<0.01) and 1.35% in Hispanic patients (p=0.2). We then evaluated APC by age groups based on decade in White individuals and found that those aged 50-59 had an increase of 2.0% (p<0.01). White patients residing in the Middle Atlantic and East North Central experienced a significant increase as well (APC=1.9%, 3.8%; p=0.03 and <0.01, respectively). Conclusions: Despite the overall decrease in the incidence of epithelial ovarian cancer in the US, the new cases of granulosa cell tumors have been increasing. Black patients and White patients aged 50-59 years residing in the Central US are at higher risk. Factors such as genetics and social determinants of health may further explain these findings. Although the incidence of ovarian cancer has decreased over the past several years, it is unclear if this finding is represented in the uncommon histologic types. As such, we investigated the incidence and trends of granulosa cell tumors of the ovary in the United States. Data were extracted from the United States Cancer Statistics, 2001-2016. Trends in the incidence was analyzed by SEER*Stat 8.3.8. Chi-square tests were used for statistical analysis. Of 5,531 patients with granulosa cell tumors, 60.7% were White, 23.9% Black, 11.2% Hispanic, and 2.6% Asian. Local, regional, and distant, and unknown stages represented 52.7%, 26.5%, 13.1%, and 7.7% of the study population. The annual percent change in incidence (APC) of White individuals was 2.15% (p<0.01) compared to 2.59% in Black patients (p<0.01) and 1.35% in Hispanic patients (p=0.2). We then evaluated APC by age groups based on decade in White individuals and found that those aged 50-59 had an increase of 2.0% (p<0.01). White patients residing in the Middle Atlantic and East North Central experienced a significant increase as well (APC=1.9%, 3.8%; p=0.03 and <0.01, respectively). Despite the overall decrease in the incidence of epithelial ovarian cancer in the US, the new cases of granulosa cell tumors have been increasing. Black patients and White patients aged 50-59 years residing in the Central US are at higher risk. Factors such as genetics and social determinants of health may further explain these findings.