Cervical Cancer Incidence in the US-Affiliated Pacific Islands

Abstract

ImportanceThe World Health Organization has called for eliminating cervical cancer as a public health problem. Accurate and up-to-date estimates of population-based cervical cancer incidence are essential for monitoring progress toward elimination and informing local cancer control strategies, but these estimates are lacking for the US-Affiliated Pacific Islands (USAPI).ObjectiveTo calculate age-standardized incidence rates for cervical cancer in the 6 USAPI and compare these rates with rates in the US (50 states and the District of Columbia).Design, Setting, and ParticipantsThis cross-sectional study used population-based data from the Pacific Regional Central Cancer Registry for women aged 20 years or older who were diagnosed with invasive cervical cancer from January 1, 2007, to December 31, 2020. The registry comprises data on all cervical cancers from the USAPI, which include 3 US territories (American Samoa, Commonwealth of the Northern Mariana Islands, and Guam) and 3 freely associated states (Federated States of Micronesia [FSM], Republic of the Marshall Islands [RMI], and Republic of Palau). Data were analyzed from July 10, 2023, to November 28, 2023.Main Outcomes and MeasuresThe main outcome was age-standardized cervical cancer incidence rates, stratified by age, stage, and histologic code for the USAPI using population estimates from 3 different sources (US Census Bureau International Database, United Nations Population Division, and Pacific Data Hub). Rate ratios were calculated to compare incidence rates between the USAPI and the US.ResultsFrom 2007 to 2020, 409 cases of cervical cancer were diagnosed in the USAPI (median age at diagnosis, 46.0 years [25th-75th percentile, 39.0-55.0 years]), with an age-standardized incidence rate ranging from 21.7 (95% CI, 19.6-23.9) to 22.1 (95% CI, 20.0-24.4) per 100 000 women, depending on the population estimate. Incidence rates were highest in RMI, ranging from 58.1 (95% CI, 48.0-69.7) to 83.4 (95% CI, 68.3-101.0) per 100 000 women, followed by FSM, ranging from 28.7 (95% CI, 23.4-34.9) to 29.8 (95% CI, 24.3-36.3) per 100 000 women. Compared with the US, incidence rates were highest in RMI (rate ratio, 5.7 [95% CI, 4.7-6.8] to 8.2 [95% CI, 6.7-9.9]) and FSM (rate ratio; 2.8; 95% CI, 2.3-3.4). Of all cases in the USAPI, 213 (68.2%) were diagnosed at a late stage.Conclusions and RelevanceIn this cross-sectional study, cervical cancer remained a major public health issue in some USAPI, with RMI reporting the highest incidence rates. The findings suggest that improvements in human papillomavirus vaccination and cancer screening coverage through efforts tailored to the unique geographic, sociocultural, economic, and health care landscape of the USAPI may reduce the burden of cervical cancer.