F N van Erning1, H J T Rutten2, H A van den Berg3, V E P P Lemmens4, H K van Halteren5. 1. Department of Research, Netherlands Comprehensive Cancer Organisation (IKNL), Eindhoven, The Netherlands; Department of Public Health, Erasmus MC University Medical Centre, Rotterdam, The Netherlands. Electronic address: f.vanerning@iknl.nl. 2. Department of Surgery, Catharina Hospital, Eindhoven, The Netherlands; Department of Surgery, Maastricht University Medical Centre, Maastricht, The Netherlands. 3. Department of Radiotherapy, Catharina Hospital, Eindhoven, The Netherlands. 4. Department of Research, Netherlands Comprehensive Cancer Organisation (IKNL), Eindhoven, The Netherlands; Department of Public Health, Erasmus MC University Medical Centre, Rotterdam, The Netherlands. 5. Department of Internal Medicine, Admiraal de Ruyter Hospital, Goes/Vlissingen, The Netherlands.
Abstract
INTRODUCTION: Adjuvant chemotherapy still is a controversial therapy for rectal cancer patients. The aim of this study was to analyze the effect of adjuvant chemotherapy on recurrence-free survival (RFS) for patients with stage III rectal cancer treated in clinical practice, taking into account which neo-adjuvant treatment patients received. METHODS: Patients from regions in the Netherlands diagnosed between 1996 and 2013 with pathological stage III rectal cancer who received short-course radiotherapy, chemoradiation or no neo-adjuvant treatment and who underwent surgery were included. After stratification by neo-adjuvant treatment, 5-year RFS according to adjuvant chemotherapy receipt was calculated using Kaplan-Meier curves. Cox regression was used to discriminate the independent effect of adjuvant chemotherapy on the risk of recurrence/death. RESULTS: The study population consisted of 829 patients, of whom 537 (65%) patients received short-course radiotherapy, 128 (15%) patients received chemoradiation and 164 (20%) patients received no neo-adjuvant treatment. Adjuvant chemotherapy was administered to 152 (18%) patients. Adjuvant chemotherapy was associated with improved 5-year RFS for patients who received short-course radiotherapy (61% vs. 46%, p = 0.005) and for patients who did not receive any neo-adjuvant treatment (70% vs. 28%, p < 0.0001). In multivariable analyses, adjuvant chemotherapy was associated with a reduced risk of recurrence/death for patients treated with short-course radiotherapy (HR 0.65, 95% CI 0.46-0.93) and for patients without neo-adjuvant treatment (HR 0.35, 95% CI 0.18-0.71), but not for patients treated with chemoradiation (HR 1.11, 95% CI 0.51-2.41). CONCLUSION: Among patients with stage III rectal cancer, the effect of adjuvant chemotherapy on RFS seems to vary by neo-adjuvant treatment.
INTRODUCTION: Adjuvant chemotherapy still is a controversial therapy for rectal cancerpatients. The aim of this study was to analyze the effect of adjuvant chemotherapy on recurrence-free survival (RFS) for patients with stage III rectal cancer treated in clinical practice, taking into account which neo-adjuvant treatment patients received. METHODS:Patients from regions in the Netherlands diagnosed between 1996 and 2013 with pathological stage III rectal cancer who received short-course radiotherapy, chemoradiation or no neo-adjuvant treatment and who underwent surgery were included. After stratification by neo-adjuvant treatment, 5-year RFS according to adjuvant chemotherapy receipt was calculated using Kaplan-Meier curves. Cox regression was used to discriminate the independent effect of adjuvant chemotherapy on the risk of recurrence/death. RESULTS: The study population consisted of 829 patients, of whom 537 (65%) patients received short-course radiotherapy, 128 (15%) patients received chemoradiation and 164 (20%) patients received no neo-adjuvant treatment. Adjuvant chemotherapy was administered to 152 (18%) patients. Adjuvant chemotherapy was associated with improved 5-year RFS for patients who received short-course radiotherapy (61% vs. 46%, p = 0.005) and for patients who did not receive any neo-adjuvant treatment (70% vs. 28%, p < 0.0001). In multivariable analyses, adjuvant chemotherapy was associated with a reduced risk of recurrence/death for patients treated with short-course radiotherapy (HR 0.65, 95% CI 0.46-0.93) and for patients without neo-adjuvant treatment (HR 0.35, 95% CI 0.18-0.71), but not for patients treated with chemoradiation (HR 1.11, 95% CI 0.51-2.41). CONCLUSION: Among patients with stage III rectal cancer, the effect of adjuvant chemotherapy on RFS seems to vary by neo-adjuvant treatment.