Subtype-dependent prognostic significance of Ki-67, histological grade, and vascular invasion in breast and colorectal cancer
Year: 2026
Type: article
Study design: Observational Study
Abstract: Traditional pathological markers remain relevant in prognostic assessment for solid tumors, but their clinical value may differ according to tumor biological context. This study evaluated the prognostic significance of Ki-67, histological grade, and vascular invasion (VI) in breast and colorectal cancer, with emphasis on subtype-specific differences. This single-center retrospective cohort included 846 patients with breast cancer or colorectal cancer who underwent curative-intent surgery between 2015 and 2022. Ki-67 expression, histological grade, and VI were extracted from pathological records. The pooled analysis was designed as an exploratory cross-cancer comparison of shared pathological features rather than as an assumption of biological equivalence between the 2 malignancies; cancer-specific and molecular-context analyses were therefore emphasized. Overall survival was assessed using Cox proportional hazards regression, with subgroup analyses according to breast cancer surrogate molecular subtype and colorectal cancer mismatch repair status. A simple Ki-67/VI score was explored for risk stratification. In multivariable analysis, increased age, stage III disease, high Ki-67 expression, and VI were independently associated with worse overall survival, whereas histological grade was not retained as an independent predictor. In breast cancer, the prognostic effect of Ki-67 was evident in luminal B and triple-negative subtypes but not in luminal A disease. In colorectal cancer, VI showed stronger prognostic value in proficient mismatch repair tumors than in deficient mismatch repair tumors. The combined Ki-67/VI score provided incremental prognostic stratification and showed better discriminatory performance than any single marker alone. Ki-67 and VI were associated with prognosis in this retrospective cohort, and the magnitude of these associations varied according to tumor biological context. The Ki-67/VI score should be regarded as exploratory and hypothesis-generating pending internal optimism correction and external validation. Interpretation of conventional pathological indicators should therefore remain cancer- and subtype-specific.
Source: Medicine
Authors: Hongyan Ji, Binzheng Liu, Lisha Xie
Language: English
Subfield: Cancer Research
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $1,950
OpenAlex ID: W7212254612