Predictive Factors for Pathologic Complete Response Following Neoadjuvant Chemoradiotherapy for Rectal Cancer.

Qi Zhang,Shiwen Mei,Jianwei Liang,Zheng Wang,Jianan Chen

doi:10.31557/apjcp.2021.22.5.1607

Abstract

Background:An accurate assessment of potential pathologic complete response(pCR) following neoadjuvant chemoradiotherapy(NCRT) is important for the appropriate treatment of rectal cancer. However, the factors that predict the response to neoadjuvant chemoradiotherapy have not been well defined. Therefore, this study analyzed the predictive factors on the development of pCR after neoadjuvant chemoradiation for rectal cancer. Methods: From January 2008 to January 2018, a total of 432 consecutive patients from a single institution patients who underwent a long-course neoadjuvant chemoradiotherapy were reviewed in this study. The clinicopathological features were analyzed to identify predictive factors for pathologic complete response in rectal cancer after neoadjuvant chemoradiation. Results:The rate of pathologic complete response in rectal cancer after neoadjuvant chemoradiation was 20.8%, patients were divided into the pCR and non-pCR groups. The two groups were well balanced in terms of age, gender, body mass index, ASA score, tumor stage, tumor differentiation, tumor location, surgical procedure, chemotherapy regimen and radiation dose. The multivariate analysis revealed that a pretreatment carcinoembryonic antigen (CEA) level of ≤5 ng/mL and an interval of ≥8 weeks between the completion of chemoradiation and surgical resection were independent risk factors of an increased rate of pCR. Conclusions: Pretreatment carcinoembryonic antigen (CEA) level of ≤5 ng/mL and an interval of ≥8 weeks between the completion of chemoradiation and surgical resection are predictive factors for pathologic complete response in rectal cancer after neoadjuvant chemoradiation. Using these predictive factors, we can predict the prognosis of patients and develop adaptive treatment strategies. A wait-and-see policy might be possible in highly selective cases.

Highlights

Neoadjuvant chemoradiotherapy (NCRT) and total mesorectal excision (TME) have been shown to significantly decrease the local recurrence rate and improve the overall survival (OS) rate (Sauer et al, 2004; Sauer et al, 2012), which have become the standard of care for patients with clinical stages II and III rectal cancer (Fleming et al, 2011)
A wait-and-see policy might be a consideration in rectal cancer patients treated with neoadjuvant chemoradiotherapy and who have already clinical complete responded to treatment (Habr-Gama et al, 2004; Maas et al, 2011)
A total of 432 consecutive patients with clinical stages II and III rectal adenocarcinoma who underwent long-course neoadjuvant chemoradiotherapy followed by TME were included in this study

Summary

Introduction

Neoadjuvant chemoradiotherapy (NCRT) and total mesorectal excision (TME) have been shown to significantly decrease the local recurrence rate and improve the overall survival (OS) rate (Sauer et al, 2004; Sauer et al, 2012), which have become the standard of care for patients with clinical stages II and III rectal cancer (Fleming et al, 2011). A wait-and-see policy might be a consideration in rectal cancer patients treated with neoadjuvant chemoradiotherapy and who have already clinical complete responded to treatment (Habr-Gama et al, 2004; Maas et al, 2011). Patients with ypT0N0 rectal cancer are a subgroup that responds well to neoadjuvant chemoradiotherapy and have favorable oncological prognosis, with a 5-year disease-free survival (DFS) rate reaching 83%-95% (Stipa et al, 2006; Capirci et al, 2008; Maas et al, 2010b; Zorcolo et al, 2012; Wasmuth et al, 2016). The present retrospective study was designed to evaluate the clinical factors that can be predicted pathologic complete response to neoadjuvant chemoradiotherapy for rectal cancer

Materials and Methods

Results

Hartmann procedure