Predictive Factors of Histological Response after Preoperative Concomitant Radiochemotherapy in Middle and Low Rectal Cancer

Asmae Ouabdelmoumen; Ali Sbai; Fouad Elmejjatti; Zohour Bourhaleb; Naima Abda; Loubna Mezouar

doi:10.31557/apjcc.2018.3.3.65

Authors

Asmae Ouabdelmoumen
Ali Sbai Departement of Radiotherapy, Center of oncology HassanII, University Hospital MOHAMED VI, km 8 route Jerada, BP:2013, Oued Ennachef, 60000 Oujda, Morocco.
Fouad Elmejjatti Departement of Radiotherapy, Center of oncology HassanII, University Hospital MOHAMED VI, km 8 route Jerada, BP:2013, Oued Ennachef, 60000 Oujda, Morocco.
Zohour Bourhaleb Departement of Radiotherapy, University Hospital IBN ROCHD, quartier des Hôpitaux, rue Sebta, 20360 Casablanca, Morocco.
Naima Abda Laboratory of Epidemiology and Public Health, Medical Faculty of Oujda, Mohammed Premier University, Morocco.
Loubna Mezouar Departement of Radiotherapy, Center of oncology HassanII, University Hospital MOHAMED VI, km 8 route Jerada, BP:2013, Oued Ennachef, 60000 Oujda, Morocco.

DOI:

https://doi.org/10.31557/apjcc.2018.3.3.65

Keywords:

Rectal cancer- adenocarcinoma- neoadjuvant radiochemotherapy- histologic response- predictive factors

Abstract

Objective: The aim of our study was to identify potential predictive factors beyond pathologic response after neoadjuvant radiochemotherapy.
Patients and Methods: Between January 2009 and December 2014, 40 patients with rectal carcinoma were included in the study. The treatment consisted of radiation ranging between 39 and 50.4 Gy associated with a concomitant chemotherapy with capecitabine. The correlation between histological response (complete response and downstaging) and potential predictive factors were investigated.
Results: Complete response was 15% (06 patients), tumor regression of 32.5% (13 patients), and the absence of tumor response of 52.5% (21 patients). In univariate analysis, the circumferential extension of the tumor was significantly associated with tumor downstaging (p = 0.007) and complete tumor response (p = 0.001). However, the delay between the RCT and the surgery was a significant predictor for downstaging (p = 0.02).
Conclusion: the parietal circumferential extension was a potential predictor of pathologic complete response (PCR) and downstaging after neoadjuvant chemoradiation. The time between the radiochemotherapy and the surgery was a significant predictor for downstaging. Delaying surgery beyond 8 weeks seems to result in the highest probability of PCR.