Prognostic value of preoperative and postoperative serum CEA in colorectal signet ring cell carcinoma.

BACKGROUND

Colorectal signet ring cell carcinoma (SRCC) is a rare and poorly prognosed tumor with limited established prognostic indicators. This study aims to investigate the prognostic value of serum carcinoembryonic antigen (CEA) in patients with colorectal SRCC.

METHODS

A retrospective, multicenter study was conducted to assess the association between CEA levels and survival outcomes in 942 patients with colorectal SRCC.

RESULTS

Patients exhibiting preoperative CEA (preCEA)-positivity demonstrated significantly lower cancer-specific survival (CSS) compared to those with preCEA-negativity in both Chinese and SEER datasets (5-year CSS: 27.50% vs. 48.27%,  = 0.01; 34.37% vs. 48.47%,  < 0.05). This disparity in outcomes was particularly notable in advanced stages (III, IV and N2; all values < 0.05), while no statistical significance was observed in earlier stages (I/II, N0 and N1; all values > 0.05). Patients with preCEA and postoperative CEA (postCEA)-negativity showed similar CSS to those with preCEA-positivity and postCEA-negativity, but those with postCEA-positivity had worse prognosis. After accounting for potential confounders, preCEA and postCEA maintained as independent predictors for CSS ( < 0.05). The nomogram model incorporating preCEA (preCEA-model) showed a C-index value of 0.75, whereas the model incorporating postCEA (postCEA-model) exhibited a C-index value of 0.73.

CONCLUSIONS

Both preoperative and postoperative elevation of CEA levels were associated with adverse outcomes, with preoperative CEA demonstrating particularly significant predictive value in advanced-stage tumors. These findings propose that CEA could be a valuable tool for dynamically monitoring the prognosis of colorectal SRCC patients.