Abstract A02: Pediatric ovarian cancer in the United States: Incidence trends over four decades
Authors: Christopher Kara M. , Boakye Eric Adjei , Barnes Justin M. , Simpson Matthew C. , Kline Brittany J. , Mass Katherine , Schwartz Theresa L. , Grabosch Shannon , Osazuwa-Peters Nosayaba 
Published: August 2020

Abstract
Objectives: Ovarian cancer is rare in children, accounting for 1% of childhood cancers. However, it is the most common cancer of the female genital tract in adolescents. Due to the rarity of the disease and the histologic and prognostic differences between pediatric and adult cases, there is a paucity of data describing incidence trends of pediatric ovarian cancer in the United States. It is unknown whether pediatric ovarian cancer has increased in incidence over time. The aim of the current study was to examine incidence and trends in pediatric ovarian cancer in the last four decades in the United States.
Methods: We queried the Surveillance, Epidemiology, and End Results 9 database from 1975-2016 for age-adjusted ovarian cancer incidence rates for pediatric cases, aged 0 to 19 years. We used Joinpoint regression analyses to examine incidence trends stratified by race (white, blacks, and others, which included Hispanics, American Indians/Alaskan Natives, and Asian Pacific Islanders), histology (carcinoma, germ cell tumor, others), and age groups (0-14, and 15-19 years).
Results: There were 897 pediatric ovarian cancer cases in the study. Whites accounted for 71.3% of tumors, and 75.6% of tumors were germ cell. Overall, there was a 46% increase in the incidence of pediatric ovarian tumors in (12.59 per 100,000 in 1975 vs. 18.38 per 100,000 in 2016). Average annual percent change (AAPC) was 0.9 (p &lt; 0.05), and APC from 1975 to 1977 was 5.1 (p = 0.5), from 1977 to 2006 APC was 0.5 (p &lt; 0.05), and from 2006 to 2016, APC was 1.3 (p &lt; 0.05). There was an upward trend in tumor incidence in all racial groups, and age-adjusted incidence rate was highest among whites (18.95 per 100,000). Among whites, APC changed significantly between 1981 and 2016 (APC = 0.8, p &lt; 0.05); however, among blacks, APC increased between 1997 and 2016 (APC = 1.3, p &lt; 0.05); and among other races, it increased between 1975 and 1997 (APC=1.1, p&lt;0.05) and between 2000 and 2016 (APC = 1.9 p &lt; 0.05).
Conclusions: In the past four decades, there has been a steady increase in the age-adjusted incidence rate of pediatric ovarian tumors, and while overall incidence is highest among whites, there has been a sharp increase in incidence among blacks and other minority populations, especially in the last two decades. This surveillance information may be relevant to issues germane to survivors of pediatric cancers, such as oncofertility issues.
Citation Format: Kara M. Christopher, Eric Adjei Boakye, Justin M. Barnes, Matthew C. Simpson, Brittany J. Kline, Katherine Mass, Theresa L. Schwartz, Shannon Grabosch, Nosayaba Osazuwa-Peters. Pediatric ovarian cancer in the United States: Incidence trends over four decades [abstract]. In: Proceedings of the AACR Special Conference on the Advances in Pediatric Cancer Research; 2019 Sep 17-20; Montreal, QC, Canada. Philadelphia (PA): AACR; Cancer Res 2020;80(14 Suppl):Abstract nr A02.