P-274 - Nodal status predict pathologic complete response following preoperative chemotherapy for colorectal liver metastases

Date 04 July 2015
Event WorldGI 2015
Session Posters
Topics Anti-Cancer Agents & Biologic Therapy
Colon Cancer
Rectal Cancer
Pathology/Molecular Biology
Presenter L. Calera
Citation Annals of Oncology (2015) 26 (suppl_4): 1-100. 10.1093/annonc/mdv233
Authors L. Calera1, I. Pajares1, R. Pazo1, J. Martinez Trufero1, P. Bueso1, A. Cebollero1, A.M. Comin1, I. Torres1, R. Jaso2, I. Trueba3, V. Alvarez4, A. Anton1, F. Rivera4
  • 1Hospital Universitario Miguel Servet, Zaragoza/ES
  • 2HUMS, Santander/ES
  • 3Hospital Txagorritxu, Vitoria/ES
  • 4Hospital Universitario Marques de Valdecilla, Santander/ES

Abstract

Introduction

Neoadjuvant chemotherapy for unresectable colorectal liver metastases can downsize tumours for curative resection. Pathological response has been shown to be a predictor for survival after preoperative chemotherapy and surgical resection of colorectal cancer liver metastases. In this study predictive factors of complete pathological response were analyzed.

Methods

Between January 2004, and January 2011, 70 patients (pts) were treated with liver surgery in a single institution. 21 pts received preoperative chemotherapy. Complete pathological response was achieved in 7 patients (33,3%). All patients were stage IV mCRC with liver metastases, were unresectable or marginally resectable tumor before chemotherapy. Pathologic response was evaluated and reported as the mean of the percentage of cancer cells remaining within each tumor. When no residual cancer cells were observed, it was considered complete response. Univariate analysis and logistic regression were performed to identify the predictors of complete pathologic response.

Results

Cumulative 5-year overall were 42% for patients who achieved complete response (no residual cancer cells) after chemotherapy. Univariate analysis identified pretreatment serum FA and GGT levels and N clinical stage as significant correlates of pathological complete response. Logistic regression analysis found N stage as independent clinical predictors for achieving complete response (odds ratio, 0,016; 95% confidence interval, 0.001-0.207; P = 0.002).

Conclusion

We demonstrated an association between low pretreatment FA and GGT levels, and N stage and pathologic complete response in patients treated with preoperative chemotherapy. N stage was independent predictors for achieving complete response. Further studies are needed to evaluate the predictive value of N stage for pathologic complete response in colorectal liver metastases.