Retrospective competing risk analysis of cancer specific and other cause death in older patients with major salivary gland carcinoma

Older patients with major salivary gland carcinoma may face substantial mortality from causes other than cancer. We conducted a retrospective population-based cohort study using the Surveillance, Epidemiology, and End Results (SEER) database to characterize competing cancer-specific death (CSD) and other-cause death (OCD) among patients aged ≥ 75 years diagnosed during 2004–2018. Cumulative incidence functions estimated absolute event probabilities, and multivariable Fine–Gray models identified predictors of each outcome. Among 4,259 patients, 1,529 experienced CSD and 2,020 experienced OCD; OCD accounted for 56.9% of all deaths. Five-year cumulative incidences were 33.2% for CSD and 29.7% for OCD. CSD was associated mainly with high grade, advanced stage, larger tumor size, positive lymph node involvement, and surgery status, whereas OCD was associated predominantly with age. Although 5-year CSD remained slightly higher, OCD became increasingly prominent during longer follow-up. Principal patterns were consistent after exclusion of SCC-coded tumors and multiple imputation, although several associations varied over follow-up in time-varying analyses. These results support competing-risk methods and geriatric-informed prognostic assessment in older patients with major salivary gland carcinoma.