Tumor deposit as a poor prognostic indicator in patients undergoing simultaneous resection forinitially resectable colorectal liver metastases

Abstract

Objective To determine the prognostic value of tumor deposits in initially resectable patients who underwent simultaneous resection for synchronous colorectal liver metastases (SCRLMs). Methods Between July 2003 and July 2015, clinicopathological and outcome data of two hundred and twelve consecutive SCRLMs patients who underwent simultaneous R0 resection were collected from SCRLMs database which was established prospectively. The prognostic value of tumor deposits was evaluated by Kaplan-Meier and Cox regression analysis. Results The positive rate of tumor deposits was 43.9% (93/212). Tumor deposits were significantly correlated with tumor differentiation, lymph node metastasis, vascular invasion and nerve invasion of the primary tumors (P=0.044, 0.001, 0.035, <0.001, respectively). Kaplan-Meier survival analysis revealed that the overall survival (OS) and disease-free survival (DFS) of SCRLMs patients with positive tumor deposits were significantly poorer than those with negative tumor deposits (P=0.003, <0.001, respectively). And multivariate analysis showed that positive tumor deposits were significantly associated with shorter DFS independent of lymph node status (P<0.001). Subgroup analysis found that in the 135 patients with positive lymph node status, the OS of patients with tumor deposits was not significantly different from those without tumor deposits (P=0.608); however, tumor deposits were significantly correlated with shorter DFS (P=0.003). In the 77 SCRLMs patients with negative lymph node status, tumor deposits were significantly associated with shorter OS and DFS (P<0.001, 0.010, respectively). Conclusion Tumor deposits may be an independent adverse prognostic factor for SCRLMs patients who underwent simultaneous R0 resection, which is significantly correlated with tumor differentiation, lymph node metastasis, vascular invasion and nerve infiltration. Key words: Colorectal neoplasms; Tumor deposits; Neoplasm metastasis; Simultaneous resection; Prognosis