Dynamic prognostic evaluation of oral squamous cell carcinoma using net and conditional survival rates: A retrospective cohort study
Year: 2026
Type: preprint
Study design: Observational Study
Abstract: Background Cancer prognosis is conventionally evaluated using the overall survival rate (OSR); however, this metric may not adequately reflect cancer-specific outcomes, particularly in older patients. Net survival rate (NSR) and conditional survival rate (CSR) may provide complementary insights into long-term prognosis. This study investigated the prognostic evaluation of oral squamous cell carcinoma (OSCC) using the NSR and CSR. Methods A retrospective cohort of 783 patients with OSCC treated between 2000 and 2014 was analyzed. OSR and NSR were estimated using the Kaplan–Meier and Pohar–Perme methods, respectively. CSR was derived from survival estimates and compared across the clinicopathological factors. Prognostic determinants were assessed using the Cox proportional hazards model. Results NSR exceeded OSR, with the most discrepancy in patients aged ≥ 65 years, reflecting increased non-cancer-related mortality. CSR analysis demonstrated that the survival probability improved over time. Survival differences progressively decreased between early- and advanced-stage diseases. Site-specific differences persisted: tongue cancer showed favorable long-term outcomes, whereas buccal mucosa and floor of mouth cancers exhibited slower CSR improvement. Sex-related differences diminished after 3 years of follow-up. Conclusion NSR and CSR provide a dynamic and clinically meaningful evaluation of the prognosis of OSCC. Non-cancer mortality substantially influenced survival outcomes in older patients, whereas CSR revealed that the prognosis improved over time among long-term survivors, even in advanced-stage disease. These findings highlight the clinical utility of dynamic survival measures for individualized prognostic assessment and follow-up planning in patients with OSCC.
Source: Research Square
Institutions: Kumamoto University, Jichi Medical University
Language: English
Topic: Head and Neck Cancer Studies
Subfield: Otorhinolaryngology
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W7221782003