Abstract Book

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ESTRO 37

Purpose or Objective Chemoradiation is the primary treatment in anal cancer. However the optimal total dose and the role of a radiation boost is still unclear. No randomized trial nor systematic review have been performed to investigate the role of brachytherapy (BCT) as boost in anal cancer. Therefore, we performed this systematic review in attempt to define the role of BCT as a boost in anal cancer Material and Methods A systematic search of the bibliographic databases PubMed, Scopus and Cochrane library from the earliest possible date through August 31, 2017 was performed. The primary outcome was loco-regional control (LRC). The secondary outcome were colostomy free survival (CFS), overall survival (OS), disease free survival (DFS), and toxicity Results Ten articles fulfilled the inclusion criteria. All the studies had retrospective design. All studies were classified to provide a level of evidence graded as 3 according to SIGN classification. Five year LCR, OS, CFS and DSF ranged: 70- 98%,66-85%,61-86%,63-82%, respectively. The toxicity was acceptable. Acute toxicity ≥ G3 ranged from 2% to 42%. The most frequent were proctitis ( range 15% - 42%), skin toxicity (range 1.4%-2% ), and diarrhea (range 1.4%- 6%). Severe late (≥ G3 ) toxicity ranged from 1.1% to 8%. The most frequent toxicities were radionecrosis (range 2%- 8%), incontinence (4%) and rectal bleeding (2.6%) Conclusion Chemoradiation is the cornerstone of treatment in anal cancer. Evidences from studies regarding the role of BCT boost in anal cancer is low. Further studies should investigate the optimal radiation dose and the number of fractions EP-1476 A qRT-PCR assay for assessment of survival in patients with locally advanced rectal cancer Z. Jing 1 , W. Yaqi 1 , S. Lijun 1 , D. Yun 1 , D. Weijuan 1 , Y. Lifeng 1 , S. Xiaoyang 1 , Z. Hui 1 , L. Liping 1 , Z. Zhen 1 1 Fudan University Shanghai Cancer Center, Department of Radiotherapy, Shanghai, China Purpose or Objective The difficulties in obtaining high-quality genome-wide transcriptome data are obstacles toward widespread adoption of colorectal cancer molecular classifiers. We investigated the clinical utility of a multigene qRT-PCR- based gene expression assay simplified from Colorectal Cancer Assigner (CRCA) for assessment of survival in patients with locally advanced rectal cancer (LARC). Material and Methods We sought validation by using RNA extracted form frozen tissues of 187 primary LARC treated with preoperative radiotherapy together with Oxaliplatin and Capecitabine weekly or Capecitabine alone. Five gene markers (MUC2, CFTR, RARRES3, SFRP2, and TFF3) by qRT-PCR were used to determine rectal cancer subtypes and their association with neoadjuvant chemoradiotherapy benefit. Results Among 187 LARC patients, 48 (25%) were stem-like. Results are shown in Table 1 and Table 2. Patients with stem-like subtype who received preoperative chemoradiotherapy had shorter OS (HR 0.762, 95% CI [0.329, 1.768]) but uncertain PFS (HR 1.125, 95% CI [0.589, 2.148]) than others. In addition, retrospective analysis demonstrated the benefit of adding Oxaliplatin to Capecitabine and radiotherapy in patients with LARC of stem-like subtypes.

Purpose or Objective After testing the feasibility in an initial Phase I trial, we analyzed the efficacy of an IMRT and integrated-boost chemoradiation scheme with a median of 17 months follow-up reaching 30.6% of complete pathological responses (ypT0N0). We update here the results of the tested scheme with an increased number of patients and longer follow-up. Material and Methods Form July 2008 to October 2016, 100 patients were treated with IMRT and integrated-boost neoadjuvant chemoradiation, all were at least T3N0 or anyT - N+ rectal cancer patients and all were previously discused on the multydisciplinary tumor board. Total prophylactic dose to pelvic lymph nodes was 46 Gy, and the boost reach up to 57.5 Gy to tumor and affected nodes. Treatment was administered in 23 fractions. All patients received concurrent standard capecitabine-based chemotherapy. Patients underwent surgery after complete reevaluation (average time 10 weeks [±4]). Results Median follow up was 35 months, we achieve a 28% ypT0N0, and a 38% Rödel 3 regression. Surgical margins were free of tumor on 96%. On follow up, only 17 patients developed distant metastases and no local relapses were found. The only factor affecting disease control was Rödel regression 1 (p=0.001), associated with higher probability of relapse. Stimated overall survival at 5 and 7 years was 89% and 78% respectively. Tumors located 5 cm or less from the anal margin have less survival (p=0.02). Acute gastrointestinal toxicity G-III or higher was 9%, genitourinary 3% and cutaneous 2%. Any grade surgical complications appeared in 39% of the patients, being ileus the most frequent. Late toxicity G-III or higher was only 4%. Conclusion IMRT and integrated-boost neoadjuvant scheme achieve a high percentage of ypT0N0 and major pathological responses. Long-term result shows the efficacy and safety of this promising approach. Further controlled studies are necessary to implement modern schemes that could improve the neoadjuvant radiotherapy in locally advanced rectal cancer. EP-1475 Brachytherapy boost after chemoradiation in anal cancer: a systematic review R. Frakulli 1 , S. Cammelli 1 , A. Guido 1 , A. Arcelli 1,2 , L. Fuccio 3 , M. Ferioli 1 , G.C. Mattiucci 4 , F. Cellini 4 , G. Macchia 5 , F. Deodato 5 , S. Cilla 6 , E. Farina 1,7 , V. Valentini 4 , G.D.A. Padula 8 , A.G. Morganti 1 , Galuppi 1 1 Radiation Oncology Center, Dept. of Experimental- Diagnostic and Specialty Medicine – DIMES- University of Bologna- S.Orsola-Malpighi Hospital, Bologna, Italy 2 Radiation Oncology Unit, Bellaria Hospital, Bologna, Italy 3 Department of Medical and Surgical Sciences, S.Orsola- Malpighi Hospital, University of Bologna, Italy 4 Department of Radiotherapy, Policlinico Universitario "Agostino Gemelli"- Catholic University, Rome, Italy 5 Radiotherapy Unit, Fondazione di Ricerca e Cura “Giovanni Paolo II”, Campobasso, Italy 6 Medical Physics Unit, Fondazione di Ricerca e Cura “Giovanni Paolo II”, Campobasso, Italy 7 Department of Radiation Oncology, CRO-IRCCS- National Cancer Institute, Aviano, Italy 8 Department of Radiation Oncology, Lacks Cancer Center Saint Mary’s Health Care, Grand Rapids- MI, USA