Marital Status, Treatment Delay, and Survival in Renal Cell Carcinoma: A Population-Based SEER Cohort Study

Background Marital status influences cancer outcomes, but whether earlier surgical access explains the "marriage benefit" in renal cell carcinoma (RCC) remains unclear. Methods Using SEER data (2010–2017), we identified adults with primary RCC of the kidney. Marital status was classified as married, single, divorced, separated, widowed, or domestic partner. Time-to-treatment (TTT) was the primary process outcome; delay was defined as TTT >30 days. Overall survival (OS) was the primary clinical outcome. Multivariable logistic regression, Kaplan–Meier and Cox models, propensity score matching (PSM), and mediation analysis were employed. Results Among 19,579 patients (median age 66.0 years; 65.2% male), median TTT was 9.0 days for married patients versus 22.0 days for separated patients and 20.0 days for domestic partners. Black race (OR 1.35), separated status (OR 1.39), and divorced status (OR 1.17) independently predicted a delay of >30 days. Five-year OS ranged from 84.2% (domestic partners) to 65.5% (widowed). Married patients had lower mortality (HR 0.82) and retained a survival advantage after PSM (HR 0.50; 6,924 matched pairs). Mediation analysis showed that TTT accounted for <1% of the association between marriage and survival. Conclusions Marriage is strongly associated with treatment timeliness and survival in RCC, yet earlier surgery explains little of this benefit, implicating broader psychosocial and structural factors. Separated, divorced, domestic partner, older, and Black patients warrant prioritised support.