Adding Tumor Deposit Status to Cancer Staging May Improve Prognostication in Colon Cancer

Sassun R, Sileo A, Ng JC, et al. Validated Integration of Tumor Deposits in N Staging for Prognostication in Colon Cancer. JAMA Surg. 2025; in press. 

Abbas A, Chu DI. Tumor Deposits—A Blind Spot in Colon Cancer Staging. JAMA Surg. 2025; in press.

In patients undergoing surgical treatment of colorectal cancer, tumor deposits are defined as “discrete tumor nodules located in the pericolorectal adipose tissue within a lymph drainage area discontinuous from the primary tumor.” These deposits are discovered in up to 20% of patients and are associated with worse oncologic outcomes. The presence of these deposits is not included in current staging systems unless lymph node metastases are documented.

The authors used data from institutional and national databases to compare outcomes in patients staged using lymph node status combined with tumor deposit status (n = 788) with patients staged according to standard AJCC staging (n = 77,790).

The data analysis showed that the new staging system provided superior overall survival stratification and that 17.1% of patients were under staged when the conventional AJCC staging system was used.

In the editorial that accompanied the article, Abbas and Chu noted that the strength of the current study included external validation using a large national database, high prognostic discrimination, and important insights regarding the impact of under staging. They recommended that tumor deposits be included in future staging systems.