Geographic disparities in surveillance adherence among individuals with <i>DICER1</i> pathogenic variants.

Abstract

e22656 Background: Individuals with pathogenic DICER1 variants require lifelong surveillance to enable early cancer detection. However, adherence to recommended surveillance varies widely, and the contribution of geographic and sociodemographic factors to adherence remains poorly understood. We evaluated adherence patterns in a single clinic (in-person and telemedicine visits) multi-state cohort to identify disparities in adherence that may inform targeted interventions. Methods: We conducted a retrospective cross-sectional study of individuals with DICER1 pathogenic variants followed at Huntsman Cancer Institute in Salt Lake City, Utah. Adherence was defined as completion of all age-appropriate recommended imaging until December 2025 (“Fully Adherent” vs “Non-Adherent”). Demographic variables included age, sex, race, insurance type, and residential geography using Rural–Urban Commuting Area (RUCA) codes. RUCA was dichotomized as Urban (1–3) vs Rural (4–10). Patterns in adherence were assessed using descriptive statistics. Results: Of 86 individuals with DICER1 variants, 66% were female, 78% identified as White, and 76% as non-Hispanic. Nearly 40% of patients (n=37) had a tumor, 6 patients had ≥1 tumor, and mean age at first tumor was 13 years. The most common tumors included sarcomas (n=10), pleuropulmonary blastomas (n=8), and ovarian Sertoli–Leydig cell tumors (n=7). Tumor development did not differ by RUCA category (urban vs rural), with similar proportions in both groups (38% vs 35%). Overall adherence to recommended surveillance imaging and follow-up clinic visits was low. Only 32 patients (37%) were up to date with recommended surveillance clinic visits, and 30 (35%) were adherent with guideline-recommended imaging (fully adherent). A significant geographic disparity emerged: 0% of rural-residing patients were fully adherent with guideline-recommended imaging compared with 45% of urban patients (Fisher p &lt; 0.0001). When we examined up-to-date clinic attendance by rural/urban geography, we found a similarly pronounced difference: 0% of rural patients were up to date with clinic follow-up compared with 58% of urban patients (Fisher p &lt; 0.0001). Additional Fisher’s tests and Wilcoxon rank-sum tests to examine distributions of surveillance imaging by sex, race, insurance, and age demonstrated no statistically significant differences according to these categories. Conclusions: Rural residence was strongly associated with non-adherence to DICER1 surveillance, with no rural patients meeting full adherence criteria. These findings highlight a critical geographic inequity in access to or uptake of recommended surveillance. Interventions tailored to rural populations — including telehealth-based surveillance pathways, decentralized imaging strategies, and navigation support — may be essential to improving outcomes for individuals with DICER1 pathogenic variants.