Department of General Surgery, Division of Colorectal Surgery, Clinica Universidad de Navarra, Pamplona, Spain.
Dis Colon Rectum. 2011 Sep;54(9):1141-6. doi: 10.1097/DCR.0b013e31821c4a60.
The finding that some rectal cancers respond to neoadjuvant chemoradiation is broadening new surgical options for the treatment of some of these tumors that, until now, required a total mesorectal excision. Nevertheless, a fine match between clinical and pathological response is required when planning conservative surgical approaches.
This study aims to prospectively validate the use of endoscopic ultrasound as a predictor of clinical and pathological tumor response in patients with locally advanced rectal cancer.
: This is an observational study of a cohort of patients undergoing chemoradiation followed by surgery.
This study was conducted at a tertiary medical center.
A total of 235 consecutive patients who underwent chemoradiation followed by surgery at a single institution during a 7-year period were included.
All tumors were staged and restaged at 4 to 6 weeks after neoadjuvant treatment. Downsizing and downstaging were calculated between the initial and posttreatment measures and correlated to the pathological stage. The accuracy of endoscopic ultrasound to predict response was determined.
Findings after chemoradiation showed T-downstaging in 54 patients (23%) and N-downstaging in 110 (47%). Overstaging occurred in 88 (37%) patients and was more commonly observed than understaging (21 patients; 9%). Related to the pathological report, endoscopic ultrasound correctly matched the T stage in 54% and the N stage in 75% of tumors. Sensitivity, specificity, and positive and negative predictive values to predict nodal involvement were 39%, 91%, 67%, and 76%. Accuracy was not influenced by such factors as age, distance of the tumor from the anal verge, or time to surgery.
This study was limited by the lack of comparison with other imaging methods.
Endoscopic ultrasound allows prediction of involved lymph nodes in 75% of the cases; however, 1 in 5 patients are missclassified as uN0 after neoadjuvant treatment. In our point of view, this percentage is too high to rely only on this diagnostic modality to support a "wait and see" approach.
新辅助放化疗后部分直肠肿瘤的疗效，拓宽了某些此类肿瘤的新的手术治疗选择，在此之前，这些肿瘤需要行全直肠系膜切除术。然而，在规划保守手术方法时，需要对临床和病理反应进行精细匹配。
本研究旨在前瞻性验证内镜超声在预测局部进展期直肠癌患者临床和病理肿瘤反应中的作用。
这是一项对接受放化疗后行手术治疗的患者进行的队列观察性研究。
这项研究在一家三级医疗中心进行。
共纳入 235 例连续患者，他们在 7 年内于一家单机构接受放化疗后行手术治疗。
所有肿瘤在新辅助治疗后 4 至 6 周进行分期和再分期。对初始和治疗后测量结果进行肿瘤缩小和降期计算，并与病理分期相关联。确定内镜超声预测反应的准确性。
放化疗后发现，54 例（23%）患者 T 分期降期，110 例（47%）患者 N 分期降期。88 例（37%）患者出现过分期，过分期比分期过低更为常见（21 例；9%）。与病理报告相比，内镜超声正确匹配了 54%的 T 期肿瘤和 75%的 N 期肿瘤。预测淋巴结受累的敏感性、特异性、阳性预测值和阴性预测值分别为 39%、91%、67%和 76%。准确性不受年龄、肿瘤距肛门缘的距离或手术时间等因素的影响。
本研究的局限性在于缺乏与其他影像学方法的比较。
内镜超声可在 75%的病例中预测受累淋巴结；然而，有 1/5 的患者在新辅助治疗后被错误分类为 uN0。在我们看来，这个百分比太高，不能仅依靠这种诊断方法来支持“等待观察”的方法。
