Consolidation radiotherapy refusal in stage I-II Hodgkin lymphoma: sociodemographic determinants and impact on survival outcomes.

[BACKGROUND] Consolidation radiotherapy following chemotherapy represents the standard of care for stage I-II classical Hodgkin lymphoma, yet treatment adherence varies in clinical practice. No previous study has systematically examined the patient characteristics associated with radiotherapy refusal or its impact on survival outcomes. We aimed to identify determinants of consolidation radiotherapy refusal and evaluate its consequences on cause-specific (CSS) and overall survival (OS).

[METHODS] We conducted a retrospective cohort study using the SEER database (2024 submission, 17 registries) analyzing patients diagnosed with stage I-II Hodgkin lymphoma between 2000 and 2022 who received chemotherapy with indicated consolidation radiotherapy. Patients were categorized based on radiotherapy receipt versus refusal. Chi-square tests compared patient characteristics between groups. Kaplan-Meier methods assessed survival outcomes, and Cox proportional hazards models identified prognostic factors among radiotherapy recipients.

[RESULTS] Among 9150 patients, 141 (1.5%) refused consolidation radiotherapy despite medical indication. Radiotherapy refusal was significantly associated with non-white ethnicity (35.5% vs. 29.9%, p < 0.01) and residence in large metropolitan areas (> 1 million population; 68.8% vs. 59.0%, p < 0.01), with a trend toward higher refusal among women (56.7% vs. 49.0%, p = 0.08). Radiotherapy refusal was significantly associated with inferior survival outcomes: 10-year OS was 83.3% versus 90.0% (p = 0.0014) and 10-year CSS was 90.4% versus 95.0% (p = 0.029) for refusers versus recipients, respectively. Among radiotherapy recipients, multivariable analysis revealed significant socioeconomic disparities, with living with a partner (HR = 0.630, p < 0.001) and higher household income (HR = 0.750, p < 0.001) as protective factors for CSS.

[CONCLUSION] Non-white ethnicity and residence in a large metropolitan area are risk factors for consolidation radiotherapy refusal in stage I-II Hodgkin lymphoma, with significant adverse associations with survival outcomes. Substantial socioeconomic disparities exist in outcomes among treated patients. These findings highlight the need for targeted educational interventions and culturally sensitive counseling to ensure equitable access to optimal care in this highly curable disease.