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International Journal of Colorectal Disease

, Volume 34, Issue 4, pp 657–666 | Cite as

Carcinoembryonic antigen reduction after medical treatment in patients with metastatic colorectal cancer: a systematic review and meta-analysis

  • Giuseppe Antonio CollocaEmail author
  • Antonella Venturino
  • Domenico Guarneri
Original Article
  • 79 Downloads

Abstract

Purpose

The introduction of new drugs and multimodal treatments for the management of patients with metastatic colorectal cancer (mCRC) has reduced the importance of time-to-event endpoints and reported the attention on the response-related endpoints. Furthermore, the prognostic role of the surgical scores before the resection of metastases has not been confirmed for multimodal treatments. The purpose of this research is to perform a meta-analysis of the studies that evaluated the relationship between carcinoembryonic antigen (CEA) response and outcome in patients with mCRC receiving systemic chemotherapy.

Methods

A systematic review of the literature on two databases and a selection of studies that evaluated the relationship between CEA response and outcome were performed according to predefined criteria. After, three meta-analyses were carried out on the selected studies, each for each outcome variable.

Results

Nineteen studies have been selected. Fourteen studies (1475 patients) have documented a close association between radiological response and CEA response (odds ratio (OR), 9.03; confidence intervals (CIs), 5.14–15.87; I2 statistic (I2), 72%). Four studies have reported a longer progression-free survival for patients with a CEA response (hazard ratio (HR), 0.73; CIs, 0.64–0.83; I2, 23%). Finally, 10 studies (13 study cohorts) have shown a strong relationship between CEA response and overall survival (OS) (HR, 0. 62; CIs, 0.55–0.70; I2, 35%).

Conclusions

CEA response merits further investigation as a surrogate endpoint of clinical trials of first-line medical therapy of patients with mCRC, and should be studied as a prognostic factor for those patients who are candidates for multimodal treatment strategies.

Keywords

Colorectal cancer Carcinoembryonic antigen Prognosis Multimodal therapy Endpoint 

Notes

Authors’ contributions

All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflicts of interest.

Supplementary material

384_2018_3230_MOESM3_ESM.jpg (29 kb)
Fig. 1 suppl: Scatter plot of meta-regression (effect of age on the relationship between CEA response and ORR). (JPG 29 kb)
384_2018_3230_MOESM1_ESM.doc (51 kb)
Table 1 suppl: Characteristics of the studies. (DOC 51 kb)
384_2018_3230_MOESM2_ESM.doc (14 kb)
Table 2 suppl: Results of meta-regressions of moderators in the analysis of CEA response with ORR (DOC 14 kb)

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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of OncologyOspedale Civile di SanremoSanremo (Imperia)Italy

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