Akasu Takayuki, Iinuma Gen, Takawa Masashi, Yamamoto Seiichiro, Muramatsu Yukio, Moriyama Noriyuki
Colorectal Surgery Division, National Cancer Center Hospital, Tokyo, Japan.
Ann Surg Oncol. 2009 Oct;16(10):2787-94. doi: 10.1245/s10434-009-0613-3. Epub 2009 Jul 18.
To achieve better prognosis and quality of life for patients with rectal cancer, extent of surgery and neoadjuvant chemoradiotherapy should accurately reflect disease extent. The aim of this study was to evaluate accuracy of high-resolution magnetic resonance imaging (HRMRI) for preoperative staging of rectal cancer.
Between 2001 and 2003, 104 patients with primary rectal cancer were examined with HRMRI and underwent radical surgery. Transmural invasion depth and lymph node metastasis were assessed prospectively and classified according to the American Joint Committee on Cancer (AJCC) tumor-node-metastasis (TNM) system by both HRMRI and histopathology, and results were compared. Criteria for mesorectal and lateral pelvic lymph node involvement were short-axis diameters of > or =5 mm and > or =4 mm, respectively.
There were 15 pT1, 25 pT2, 50 pT3, and 14 pT4 tumors. Overall accuracy rate for transmural invasion depth was 84%. The mesorectal fascia could be visualized in 98% of patients. Twenty-three patients had mesorectal fascia involvement and the overall accuracy rate was 96% (sensitivity, 96%; specificity, 96%). Fifty-three patients had mesorectal lymph node metastasis and the overall accuracy rate was 74% (sensitivity, 83%; specificity, 64%). Lateral pelvic lymph node metastasis was observed in 15 patients and the overall accuracy rate was 87% (sensitivity, 87%; specificity, 87%).
HRMRI was moderately accurate for prediction of mesorectal lymph node metastasis and highly accurate regarding transmural invasion depth, and mesorectal fascia and lateral pelvic node involvement. Therefore, HRMRI appears useful for preoperative decision-making in rectal cancer treatment.
为了使直肠癌患者获得更好的预后和生活质量，手术范围和新辅助放化疗应准确反映疾病范围。本研究的目的是评估高分辨率磁共振成像（HRMRI）对直肠癌术前分期的准确性。
2001年至2003年期间，对104例原发性直肠癌患者进行了HRMRI检查并接受了根治性手术。前瞻性评估透壁浸润深度和淋巴结转移情况，并根据美国癌症联合委员会（AJCC）的肿瘤-淋巴结-转移（TNM）系统，通过HRMRI和组织病理学进行分类，然后比较结果。直肠系膜和侧盆腔淋巴结受累的标准分别为短轴直径≥5mm和≥4mm。
有15例pT1、25例pT2、50例pT3和14例pT4肿瘤。透壁浸润深度的总体准确率为84%。98%的患者可观察到直肠系膜筋膜。23例患者有直肠系膜筋膜受累，总体准确率为96%（敏感性96%；特异性96%）。53例患者有直肠系膜淋巴结转移，总体准确率为74%（敏感性83%；特异性64%）。15例患者观察到侧盆腔淋巴结转移，总体准确率为87%（敏感性87%；特异性87%）。
HRMRI对直肠系膜淋巴结转移的预测准确性中等，对透壁浸润深度、直肠系膜筋膜和侧盆腔淋巴结受累的预测准确性高。因此，HRMRI似乎有助于直肠癌治疗的术前决策。
