Tumor deposits for prognostic prediction in colorectal cancer patients: a systematic review and meta-analysis

Colorectal cancer (CRC) is one of the most prevalent cancers worldwide. Tumor deposits (TDs) are discrete tumor nodules located within the lymphatic drainage area of the primary carcinoma. They lack identifiable lymph node tissue and show no evidence of vascular or neural structures. Although TDs were incorporated into the tumor-node-metastasis (TNM) staging system in 1997, their prognostic utility has not been fully elucidated under the current eighth edition. Therefore, the current meta-analysis aimed to investigate the prognostic role of TDs in patients with CRC. Web of Science, PubMed, the Cochrane Library, and Embase were searched up to January 2, 2025, and an updated search was performed on March 15, 2026. Studies examining the association of TDs with cancer-specific survival (CSS), overall survival (OS), and disease-free survival (DFS) in patients with CRC were included. After literature screening, data extraction, and quality assessment, a meta-analysis was conducted in Stata 18.0. Thirty-four eligible studies were included, of which 31 were retrospective and three were prospective. The presence of TDs was significantly associated with poorer survival outcomes in patients with CRC. Specifically, TDs were associated with poorer OS [hazard ratio (HR) (95% confidence interval [CI]): 1.48 (1.41, 1.56)], DFS [1.75 (1.38, 2.23)], and CSS [1.52 (1.43, 1.62)] (all P < 0.05). TDs are adverse prognostic factors for OS, DFS and CSS in colorectal cancer. However, the association between TD-positivity and poor OS and CSS should be interpreted cautiously. This meta-analysis strengthens the clinical relevance of TD-positivity as an adverse pathological feature. Nevertheless, current evidence remains insufficient to establish its independent prognostic value within the current TNM staging system. Moreover, using TD-positivity as a basis for updating the TNM staging system requires external validation. International Prospective Register of Systematic Reviews, CRD420250651373.