Department of Surgery, School of Medicine of the Federal University of Ceará, Ceará, Brazil.
Colorectal Dis. 2011 Dec;13(12):1344-50. doi: 10.1111/j.1463-1318.2010.02471.x.
The aim of this study was to identify criteria for three-dimensional anorectal ultrasonography (3D-AUS) to assess the response of rectal cancer to chemoradiotherapy; the 3D-AUS results were compared with the histopathological findings of the resected specimen.
Thirty-five patients underwent 3D-AUS and were grouped according to the presence (GI; n = 19) or absence (GII; n = 16) of anal canal invasion. All patients received chemoradiotherapy, then underwent a second 3D-AUS. The response (complete, partial or insignificant and lymph node metastasis) was evaluated. Tumour length (cm) and volume (cm(3) ), length and volume regression percentage (%), distal length regression, and distance between the distal tumour edge and the proximal border of the internal anal sphincter were measured before and after chemoradiotherapy. All patients underwent surgery, and the 3D-AUS image was compared with the histopathological findings.
Before chemoradiotherapy, the average tumour length was similar in G1 and GII, but the volume differed significantly (P = 0.0408). The response was insignificant in seven (37%) patients, partial in 10 (53%) patients and complete in two (10%) patients in GI. The corresponding figures for GII were one (6%) patient, 12 (75%) patients and three (19%) patients (P = 0.0318). The agreement between pathological and post-chemoratherapy 3D-AUS findings was almost identical for the identification of residual tumour or complete response (κ = 1.0) and substantial for lymph node metastases (κ = 0.74). The mean distance to the internal anal sphincter was greater in GII. A sphincter-saving resection was performed in 2/19 patients in GI and in 14/16 patients in GII (P < 0.0001). The histopathological examination revealed a free distal margin.
3D-AUS was shown to evaluate accurately the response to chemoradiotherapy, helping in the selection of patients for a sphincter-saving resection. The distance between the tumour and the internal anal sphincter was the most important parameter in this respect.
本研究旨在确定三维直肠肛门超声（3D-AUS）评估直肠癌放化疗反应的标准；将 3D-AUS 结果与切除标本的组织病理学发现进行比较。
35 例患者接受了 3D-AUS 检查，并根据是否存在（GI 组，n=19）或不存在（GII 组，n=16）肛门管侵犯进行分组。所有患者均接受放化疗，然后再次进行 3D-AUS 检查。评估反应（完全、部分或不明显以及淋巴结转移）。在放化疗前后测量肿瘤长度（cm）和体积（cm³）、长度和体积消退百分比（%）、远端长度消退和远端肿瘤边缘与内肛门括约肌近端边界之间的距离。所有患者均接受手术，并将 3D-AUS 图像与组织病理学发现进行比较。
在放化疗前，GI 组和 GII 组的平均肿瘤长度相似，但体积差异有统计学意义（P=0.0408）。GI 组中 7 例（37%）患者反应不明显，10 例（53%）患者部分反应，2 例（10%）患者完全反应。GII 组中相应的数字为 1 例（6%）患者，12 例（75%）患者和 3 例（19%）患者（P=0.0318）。对于残留肿瘤或完全反应的识别，病理和放化疗后 3D-AUS 结果之间的一致性几乎相同（κ=1.0），对于淋巴结转移的一致性也很高（κ=0.74）。GII 组的内肛门括约肌距离平均值较大。在 GI 组中，2/19 例患者和 GII 组中 14/16 例患者进行了保留括约肌的切除术（P<0.0001）。组织病理学检查显示远端切缘无肿瘤。
3D-AUS 可准确评估放化疗反应，有助于选择适合保留括约肌切除术的患者。肿瘤与内肛门括约肌之间的距离是这方面最重要的参数。
