Holman Fabian A, Haddock Michael G, Gunderson Leonard L, Kusters Miranda, Nieuwenhuijzen Grard A P, van den Berg Hetty A, Nelson Heidi, Rutten Harm J T
Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands.
Department of Radiation Oncology, Mayo Clinic, Rochester, MN, USA.
J Gastrointest Oncol. 2016 Dec;7(6):903-916. doi: 10.21037/jgo.2016.07.01.
The aim of this study is to analyse the pooled results of intraoperative electron beam radiotherapy (IOERT) containing multimodality treatment of locally advanced T4 rectal cancer, initially unresectable for cure, from the Mayo Clinic, Rochester, USA (MCR) and Catharina Hospital, Eindhoven, The Netherlands (CHE), both major referral centers for locally advanced rectal cancer. A rectal tumor is called locally unresectable for cure if after full clinical work-up infiltration into the surrounding structures or organs has been demonstrated, which would result in positive surgical margins if resection was the initial component of treatment. This was the reason to refer these patients to the IOERT program of one of the centers.
In the period from 1981 to 2010, 417 patients with locally unresectable T4 rectal carcinomas at initial presentation were treated with multimodality treatment including IOERT at either one of the two centres. The preferred treatment approach was preoperative (chemo) radiation and intended radical surgery combined with IOERT. Risk factors for local recurrence (LR), cancer specific survival, disease free survival and distant metastases (DM) were assessed.
A total of 306 patients (73%) underwent a R0 resection. LRs and metastases occurred more frequently after an R1-2 resection (P<0.001 and P<0.001 respectively). Preoperative chemoradiation (preop CRT) was associated with a higher probability of having a R0 resection. Waiting time after preoperative treatment was inversely related with the chance of developing a LR, especially after R+ resection. In 16% of all cases a LR developed. Five-year disease free survival and overall survival (OS) were 55% and 56% respectively.
An acceptable survival can be achieved in treatment of patients with initially unresectable T4 rectal cancer with combined modality therapy that includes preop CRT and IOERT. Completeness of the resection is the most important predictive and prognostic factor in the treatment of T4 rectal cancer for all outcome parameters. IOERT can reduce the LR rate effectively, especially in R+ resected patients.
本研究旨在分析美国罗切斯特梅奥诊所（MCR）和荷兰埃因霍温卡特琳娜医院（CHE）这两个局部晚期直肠癌主要转诊中心对最初无法根治性切除的局部晚期T4直肠癌进行包含多模态治疗的术中电子束放疗（IOERT）的汇总结果。如果经过全面临床检查证实直肠肿瘤已浸润周围结构或器官，若手术切除作为初始治疗手段则会导致手术切缘阳性，那么该直肠肿瘤就被称为无法根治性切除。这就是将这些患者转诊至其中一个中心的IOERT项目的原因。
1981年至2010年期间，417例初诊时局部无法切除的T4直肠癌患者在两个中心之一接受了包括IOERT在内的多模态治疗。首选治疗方法是术前（化疗）放疗以及意向性根治性手术联合IOERT。评估局部复发（LR）、癌症特异性生存、无病生存和远处转移（DM）的危险因素。
共有306例患者（73%）接受了R0切除。R1 - 2切除后LR和转移的发生频率更高（分别为P<0.001和P<0.001）。术前放化疗（preop CRT）与更高的R0切除概率相关。术前治疗后的等待时间与发生LR的机会呈负相关，尤其是在R +切除后。所有病例中有16%发生了LR。五年无病生存率和总生存率（OS）分别为55%和56%。
对于最初无法切除的T4直肠癌患者，采用包括preop CRT和IOERT的联合治疗方式可实现可接受的生存率。切除的完整性是T4直肠癌治疗中所有结局参数最重要的预测和预后因素。IOERT可有效降低LR率，尤其是在R +切除的患者中。
