Son Il Tae, Kim Young Hoon, Lee Kyoung Ho, Kang Sung Il, Kim Duck-Woo, Shin Eun, Lee Keun-Wook, Ahn Soyeon, Kim Jae-Sung, Kang Sung-Bum
Department of Surgery, Seoul National University Bundang Hospital, Seongnam, South Korea.
Department of Radiology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, South Korea.
Surgery. 2017 Jul;162(1):152-163. doi: 10.1016/j.surg.2017.01.011. Epub 2017 Feb 23.
The oncologic importance of threatened mesorectal fascia detected with magnetic resonance imaging is obscured by the heterogeneity of preoperative treatments. We evaluated the oncologic relevance of threatened mesorectal fascia detected with consecutive magnetic resonance imaging performed before and after long-course, concurrent chemoradiotherapy (LCRT) for mid or low rectal cancer.
We evaluated 196 patients who underwent total mesorectal excision with LCRT. Threatened mesorectal fascia was defined as a shortest distance from tumor to mesorectal fascia of ≤ 1 mm on magnetic resonance imaging. Multivariate analyses for disease-free survival using magnetic resonance imaging-based parameters were conducted with a Cox proportional hazard model before and after LCRT, respectively.
The pathologic positivity of the circumferential resection margin was greater for threatened mesorectal fascia than for clear mesorectal fascia (pre-LCRT, 14.8% vs 3.0%, P = .004; post-LCRT, 15.4% vs 4.5%, P = .025). At a median follow-up of 68 months, 3-year disease-free survival was worse for threatened mesorectal fascia than for clear mesorectal fascia (pre-LCRT, 77.0% vs 88.1%, P = .023; post-LCRT, 76.9% vs 86.6%, P = .029). On multivariate analyses, threatened mesorectal fascia on pre-LCRT magnetic resonance imaging was an independent factor for poor disease-free survival (hazard ratio = 2.153, 95% confidence interval, 1.07-4.32, P = .031), whereas threatened mesorectal fascia on post-LCRT magnetic resonance imaging was not (hazard ratio = 1.689, 95% confidence interval, 0.77-3.66, P = .189).
This study confirms that magnetic resonance imaging-detected threatened mesorectal fascia predicts poor oncologic outcomes for mid or low rectal cancer and shows that the diagnostic performance of pre-LCRT magnetic resonance imaging is different from that of post-LCRT magnetic resonance imaging.
术前治疗的异质性掩盖了磁共振成像检测到的直肠系膜筋膜受威胁的肿瘤学重要性。我们评估了在中低位直肠癌的长程同步放化疗（LCRT）前后连续进行磁共振成像检测到的直肠系膜筋膜受威胁的肿瘤学相关性。
我们评估了196例行LCRT并接受全直肠系膜切除术的患者。磁共振成像上，直肠系膜筋膜受威胁定义为肿瘤与直肠系膜筋膜的最短距离≤1毫米。分别在LCRT前后，使用基于磁共振成像的参数，通过Cox比例风险模型对无病生存期进行多因素分析。
直肠系膜筋膜受威胁组的环周切缘病理阳性率高于直肠系膜筋膜清晰组（LCRT前，14.8%对3.0%，P = 0.004；LCRT后，15.4%对4.5%，P = 0.025）。中位随访68个月时，直肠系膜筋膜受威胁组的3年无病生存期低于直肠系膜筋膜清晰组（LCRT前，77.0%对88.1%，P = 0.023；LCRT后，76.9%对86.6%，P = 0.029）。多因素分析显示，LCRT前磁共振成像检测到的直肠系膜筋膜受威胁是无病生存期差的独立因素（风险比 = 2.153，95%置信区间，1.07 - 4.32，P = 0.031），而LCRT后磁共振成像检测到的直肠系膜筋膜受威胁则不是（风险比 = 1.689，95%置信区间，0.77 - 3.66，P = 0.189）。
本研究证实磁共振成像检测到的直肠系膜筋膜受威胁预示着中低位直肠癌的肿瘤学预后不良，并表明LCRT前磁共振成像的诊断性能与LCRT后磁共振成像不同。
