2120 - Radiation Therapy Utilization and Survival Disparities in Locally Advanced Pancreatic Cancer by Race, Income and Geography: A Population-Based Analysis

03:00pm - 04:00pm ET

Poster Hall - Exhibit Hall A

Screen: 31

POSTER

Presenter(s)

Jeril Lasington, MD, MS, MBBS - New York Medical College at St.Mary's and St. Clare's, Denville, NJ

J. Lasington¹, L. S. Mathew Lasington², S. Umamaheshwaran³, and C. D. Dirican⁴; ¹New York Medical College at St. Mary's and St. Clare's, Denville, NJ, ²Rutger's University, East Hanover, NJ, ³Personio, Manhattan, NY, ⁴New York Medical College at St.Mary's and St. Clare's, Denville, NJ

Purpose/Objective(s): Radiotherapy (RT) utilization for locally advanced pancreatic cancer (LAPC) has declined as systemic therapy has evolved. We characterized national trends in RT utilization and survival disparities by race/ethnicity, income, and geography using the SEER database

Materials/Methods: We identified 41,071 patients with Stage II/III pancreatic cancer (SEER, 2004-2022) and assessed RT utilization trends by race/ethnicity (Non-Hispanic White [NHW], Non-Hispanic Black [NHB], Non-Hispanic Asian/Pacific Islander [NHAPI], Hispanic), area-level median household income (low [<$55K] to high [=$95K]), and geography (large metro [=1M], small metro, rural). Overall Survival (OS) was evaluated by Kaplan-Meier analysis. Multivariable Cox regression was performed adjusting for age, sex, race, stage, chemotherapy, RT, income, and geography (concordance=0.66).

Results: RT utilization declined from ~37% (2004) to ~18% (2022) across all groups. Hispanic patients had persistently lower RT use (23.7% vs 28-30% others), with a widening gap by 2022. Large metros had the lowest RT rates (27.3%) vs smaller metros (31.1%) and rural (30.9%), reflecting earlier chemotherapy-first adoption at academic centers. On multivariable analysis, RT was independently associated with improved OS (HR 0.94, p<0.005); chemotherapy had the strongest effect (HR 0.70, p<0.005). Significant disparities persisted in Non-Hispanic Black (NHB) (HR 1.12, p<0.005), low income (HR 1.16, p<0.005), rural (HR 1.07, p<0.005). Stage III carried HR 1.40 vs Stage II (p<0.005).

Conclusion: RT utilization for LAPC has declined substantially, consistent with evolving systemic therapy paradigms. Non-Hispanic Black (NHB) patients, low-income areas, and rural residents experience worse survival independent of treatment. Hispanic patients show a widening RT utilization gap. High-resource settings de-adopted RT fastest, suggesting uneven dissemination of treatment innovation. These results underscore the need for equitable access to guideline-concordant multimodality care.

Multivariable Cox Regression and RT Utilization by Demographic Subgroup (N=41,071)

Category	Variable	RT %	HR	95% LCI	95% UCI	z	p	Note
*Treatment*	*RT receipt*	*27.5*	*0.94*	*0.92*	*0.97*	*-4.52*	*<0.005*	*Protective*
	*Chemotherapy*	-	*0.70*	*0.69*	*0.72*	*-20.24*	*<0.005*	*Strongest*
*Race*	*NHB*	*28.8*	*1.12*	*1.08*	*1.16*	*6.40*	*<0.005*	*Disparity*
	*NHAPI*	*28.5*	*0.97*	*0.93*	*1.01*	*-1.69*	*0.09*	—
	*Hispanic*	*23.7*	*1.02*	*0.99*	*1.06*	*1.29*	*0.20*	*Low RT%*
*Income*	*Low (<$55K)*	*31.4*	*1.16*	*1.13*	*1.19*	*11.29*	*<0.005*	*Disparity*
*Geography*	*Rural*	*30.9*	*1.07*	*1.03*	*1.11*	*3.45*	*<0.005*	*Disparity*
	*Sm Metro*	*31.1*	*1.02*	*1.00*	*1.05*	*1.81*	*0.07*	-
*Stage*	*III vs II*	-	*1.40*	*1.37*	*1.44*	*28.45*	*<0.005*	*Expected*