Evaluation of a 36 Gy elective node irradiation dose in anal cancer.

PURPOSE: To retrospectively analyze the efficacy of 36 Gy of elective node irradiation and report patterns of recurrence in patients with anal cancer treated by chemoradiation with the same radiotherapy (RT) treatment scheme. METHODS AND MATERIALS: Between January 1996 and December 2013, 142 patients with anal squamous cell cancer were scheduled to receive a dose of 36 Gy of elective node irradiation (ENI) to the inguinal area and whole pelvis over 4 weeks followed after a 2-week gap by a boost dose of 23.4 Gy over 17 days to the macroscopic disease. Mitomycin C combined with fluorouracil, capecitabin or cisplatin was given at day 1 of each sequence of RT. RESULTS: Disease stages were I: 3, II: 78, IIIA: 23, IIIB: 38. Compliance rates were 97.2% with RT and 87.9% with chemotherapy. After a median follow up of 48 months [3.6-192], estimated 5-year overall survival and colostomy-free survival were 75.4% and 85.3% respectively. Eleven patients (7.7%) never achieved a complete response, 15 had a local component of recurrence and 5 a regional one. One patient had failure in the common iliac node area outside the treatment fields. The inguinal control rate was 98.5%. The 5-year tumor and nodal control rates were 81.5% and 96.0%, respectively. CONCLUSION: Chemoradiation with a dose of 36 Gy ENI achieved excellent nodal control. However, it is necessary to improve the 5-year control rate of the primary tumor. Omitting the gap and using additional doses per fraction or hyper-fractionation are to be explored.

Selection of appropriate end-points (pCR vs 2yDFS) for tailoring treatments with prediction models in locally advanced rectal cancer.

PURPOSE: Personalized treatments based on predictions for patient outcome require early characterization of a rectal cancer patient's sensitivity to treatment. This study has two aims: (1) identify the main patterns of recurrence and response to the treatments (2) evaluate pathologic complete response (pCR) and two-year disease-free survival (2yDFS) for overall survival (OS) and their potential to be relevant intermediate endpoints to predict. METHODS: Pooled and treatment subgroup analyses were performed on five large European rectal cancer trials (2795 patients), who all received long-course radiotherapy with or without concomitant and/or adjuvant chemotherapy. The ratio of distant metastasis (DM) and local recurrence (LR) rates was used to identify patient characteristics that increase the risk of recurrences. FINDINGS: The DM/LR ratio decreased to a plateau in the first 2 years, revealing it to be a critical follow-up period. According to the patterns of recurrences, three patient groups were identified: 5-15% had pCR and were disease free after 2 years (excellent prognosis), 65-75% had no pCR but were disease free (good prognosis) and 15-30% had neither pCR nor 2yDFS (poor prognosis). INTERPRETATION: Compared with pCR, 2yDFS is a stronger predictor of OS. To adapt treatment most efficiently, accurate prediction models should be developed for pCR to select patients for organ preservation and for 2yDFS to select patients for more intensified treatment strategies.

Role of radiotherapy with surgery for T3 and resectable T4 rectal cancer: evidence from randomized trials.

PURPOSE: The main treatment for resectable rectal cancer T2-T4 N0-N2 M0 is surgery. The benefit of preoperative or postoperative radiation therapy can be analyzed in terms of improvement of local control, sphincter preservation, and survival weighted against increased toxicity. METHODS: Only randomized trials can provide strong evidence of a positive cost-benefit ratio of such combined approach. The most recent trials were reviewed. RESULTS: Three randomized trials, including the latest German CAO-ARO trial, have demonstrated the superiority of preoperative radiotherapy with or without chemotherapy (vs. postoperative) in terms of local control and toxicity. The Ducth TME trial showed that even with modern standard surgery, preoperative radiotherapy improved local control. Preoperative irradiation using a high dose in a small volume and a long interval before surgery may improve sphincter preservation (Lyon trials). Concurrent chemoradiation (FFCD 9203, EORTC 22921, did not significantly improve sphincter preservation or survival but significantly reduced the local recurrence rate. CONCLUSIONS: In 2005 examination of randomized trials provides evidence for the benefit of preoperative chemoradiation in improving local control and probably sphincter preservation in rectal cancer. Randomized trials should be designed to further demonstrate improved sphincter preservation and to increase survival using adjuvant medical treatments.