Predictive factors of disease-free survival after complete pathological response to neoadjuvant radiotherapy for rectal adenocarcinoma: retrospective case series

Amine Souadka,Basma El Khannousi,Khalid Mazaz,Tijani El Harroudi,Badr Serji,Amine Benkabbou,Mourad Abid,Tarik Souiki,Raouf Mohsine,Sidi Mohammed Bouchentouf,A Souadka ,Aziz Zentar,Hadj Omar El Malki,Mohammed Raiss ,A Belkouchi ,L Ifrine ,M Ahallat ,Mohammed Anass Majbar,A Hrora

doi:10.1186/s12885-019-6239-3

Abstract

BackgroundMany data suggest that patients with low rectal adenocarcinoma who achieved ypT0N0 status have improved survival and disease-free survival (DFS) compared to all other stages however only few data are available regarding the specific prognosis factors of this subgroup. This study aimed to evaluate predictive factors for disease free survival after complete pathological response (CPR) in cases of low rectal adenocarcinoma.Materials and methodsFrom January 2005 to December 2013, all patients with low rectal adenocarcinoma who underwent neoadjuvant chemoradiotherapy followed by total mesorectal excision and achieved CPR were included at 7 Moroccan and 1 Algerian centres. Predictive factors for disease-free survival were analysed by uni and multivariate analysis.ResultsEigthy-four (12.1%) patients achieved a CPR (ypT0N0). Multivariate analysis revealed that both poorly differentiated tumors (OR, 9.23; 95 CI 1.35–62.82; P = 0.023) and the occurrence of perineal sepsis (OR, 13.51; 95 CI 1.96–93.12; P = 0.008) were independently associated with impaired DFS.ConclusionsPatients with low rectal cancer who exhibited a CPR after neoadjuvant therapy have good prognoses; however, the occurrence of perineal sepsis and/or poor initial differentiation may be associated with impaired DFS in these patients.Trial registration: The study was retrospectively registered the 28th July 2018 in ClinicalTrials.gov register with the reference NCT03601689.

Highlights

Many data suggest that patients with low rectal adenocarcinoma who achieved ypT0N0 status have improved survival and disease-free survival (DFS) compared to all other stages only few data are available regarding the specific prognosis factors of this subgroup
Patients with low rectal cancer who exhibited a complete pathological response (CPR) after neoadjuvant therapy have good prognoses; the occurrence of perineal sepsis and/or poor initial differentiation may be associated with impaired DFS in these patients
Currently, the standard treatment for mid-low locally advanced rectal cancer is neoadjuvant-radiation therapy followed by curative surgical resection according to the guidelines of both the European Society of Medical Oncology (ESMO) and the National Comprehensive Cancer Network (NCCN) [1]

Summary

Introduction

Many data suggest that patients with low rectal adenocarcinoma who achieved ypT0N0 status have improved survival and disease-free survival (DFS) compared to all other stages only few data are available regarding the specific prognosis factors of this subgroup. Most patients exhibit a substantial downstaging that may lead to complete pathological responses (CPRs) in 15 to 20% of cases, as defined by the absence of viable tumour cells after full pathologic examination of the resected specimen (ypT0N0), which is referred to as stage 0 disease [2]. These findings have helped many authors to reconsider the need for surgical resection after a CPR [3,4,5,6]; no definitive surrogate of a CPR (clinical, biological or radiological) has been reported in the literature, and surgical resection remains the standard treatment. The aim of this study was to evaluate the long-term oncologic outcomes and predictive factors for DFS after a CPR of low rectal adenocarcinoma

Objectives

Methods

Results

Discussion

Conclusion