The study set out to address a long-standing controversy in surgical oncology: whether being very old is, by itself, an independent prognostic factor in gastric cancer. To test this, the team stratified patients using age cutoffs of 80 and 85 years and compared clinicopathological characteristics, postoperative complication rates, and survival outcomes across the resulting groups.

Before any statistical adjustment, the results appeared to support the conventional wisdom. Patients aged 80 and older, and separately those aged 85 and older, showed significantly worse overall survival and recurrence-free survival than their younger counterparts. Superficially, this seemed to confirm that advancing age carries a poorer outlook after curative-intent surgery.

However, the picture changed after the researchers applied propensity score matching, a statistical technique designed to balance the comparison groups for confounding variables. Once patients of different ages were matched on these baseline factors, the apparent survival differences between age groups disappeared, and no significant differences remained in either overall or recurrence-free survival.

Postoperative safety told a similar story. After propensity score matching, the rates of postoperative complications showed no significant differences between the age groups, indicating that carefully selected elderly patients were not intrinsically more likely to suffer surgical complications simply because of the number of years they had lived.

Instead, multivariate analysis identified a set of biologically and functionally meaningful factors as independent predictors of overall survival: performance status, which measures a patient’s functional capacity; the Charlson Comorbidity Index, which quantifies the burden of coexisting diseases; the neutrophil-to-lymphocyte ratio, a marker of systemic inflammation; the Prognostic Nutritional Index, which reflects nutritional and immune status; the type of gastrectomy performed; and the pathological stage of the cancer.

Crucially, chronological age was not a significant prognostic factor at either the 80-year or the 85-year cutoff in these multivariate models. The findings suggest that what matters is not how old a patient is on paper, but the patient’s physiological reserve, comprising functional fitness, comorbidity burden, nutritional condition, and inflammatory state.

The authors conclude that surgical decisions for gastric cancer patients aged 75 and older should be grounded in a comprehensive assessment of these biological parameters rather than age alone. As the study is retrospective and limited to patients who underwent R0 resection, its conclusions apply to patients selected for curative surgery, and the findings suggest that age should not serve as a standalone criterion for withholding or recommending operation in this population.

Subject of Research: Prognostic factors and chronological age in elderly gastric cancer patients after curative resection

Article Title: Chronological age vs. biological reserve: redefining prognostic factors in gastric cancer patients aged 75 and older: a retrospective study

Article References: Toyokawa, T., Yoshii, M., Deguchi, S., Seki, Y., Kuroda, K., Kasashima, H., Miki, Y., Tamura, T., Shibutani, M., & Maeda, K. (2026). Chronological age vs. biological reserve: redefining prognostic factors in gastric cancer patients aged 75 and older: a retrospective study. BMC Cancer. https://doi.org/10.1186/s12885-026-17234-1

Image Credits: AI Generated

DOI: 10.1186/s12885-026-17234-1

Keywords: gastric cancer, elderly patients, R0 resection, propensity score matching, performance status, Charlson Comorbidity Index, neutrophil-to-lymphocyte ratio, Prognostic Nutritional Index, overall survival, retrospective study, biological reserve, Chronological