Application of Endoscopic Sonography in Preoperative Staging of Rectal Cancer

Abstract

Six-Year Experience n recent years, the development of new surgical techniques and use of neoadjuvant therapy have modified the management and improved the prognosis of rectal cancer. The selection of suitable treatment strategies for rectal cancer is based on accurate staging of the lesions. Several methods have been reported for imaging rectal cancer, such as sonography, computed tomography, magnetic resonance imaging (MRI), and positron emission tomography/computed tomography. [1][2][3][4][5][6][7][8][9][10][11][12] Computed tomography and MRI have advantages of imaging distant metastases (M staging), but for locoregional invasion imaging (T and N staging), endoscopic sonography may be a better choice, especially for assessing the invasive depth of a lesion (T staging). Several studies have shown good accuracy for endoscopic sonography in rectal cancer staging. 3,4,7,8,13 These studies showed that the overall accuracy of T staging fluctuated from 72% to 90%, and the overall accuracy of N staging ranged from 69% to 80%.Shiyong Lin, PhD, Guangyu Luo, MD, Xiaoyan Gao, Hongbo Shan, MD, Yin Li, MD, Rong Zhang, MD, Jianjun Li, MD, Longjun He, PhD, Guobao Wang, PhD, Guoliang Xu, MD Received January 20, 2011, ORIGINAL RESEARCHObjectives-The aim of this study was to evaluate our experience with the application of endoscopic sonography in preoperative staging of rectal cancer. April 2004 and May 2010, 192 patients with rectal cancer first underwent endoscopic sonography and then underwent surgery at our hospital. None of the patients in this study received neoadjuvant therapy. The endoscopic sonographic staging results were compared with those of postoperative pathologic staging. Methods-BetweenResults-The accuracy of overall T staging was 86.5%, and for T1, T2, T3, and T4, the accuracy rates were 86.7%, 94.0%, 86.2%, and 65.5%, respectively. The accuracy of T staging for ulcerated lesions was significantly lower than that for nonulcerated lesions (P = .013). The accuracy of T staging between nontraversable stenotic lesions and traversable lesions was also significantly different (P = .002). The accuracy of N staging was 77.8%, and the specificity and sensitivity were 85.6% and 74.2%, respectively.Conclusions-Endoscopic sonography is safe and effective for preoperative staging of rectal cancer and should be a routine examination before surgery. As for ulcerated and nontraversable stenotic lesions, however, the results of endoscopic sonographic staging could be doubtful. Moreover, the accuracy of endoscopic sonographic N staging still needs modification by further research.

Learning curve of endorectal ultrasonography in preoperative staging of rectal carcinoma

“…In our study, the overall accuracy of T staging was 67%, which is lower compared to that previously reported, but similar to that reported by Garcia-Aguilar, with 16% of the tumors overstaged and 17% understaged, which is similar to the percentages (2.0-23.9% and 2.5-17.0%, respectively) reported in the literature (16). ERUS accurately identified 2 of 3 pT1 tumors and 188 (71%) of 264 pT3 or pT4 tumors that were candidates for preoperative chemoradiation therapy.…”

Performance of Endoscopic Ultrasound in Staging Rectal Adenocarcinoma Appropriate for Primary Surgical Resection

“…[18][19][20][21][22][23][24][25] Although prior estimates of the diagnostic performance of EUS have tended to consider all tumor stages equally, this study focused on staging thresholds that represent the most salient branch points in therapeutic decision making.…”

Value of transrectal ultrasonography for tumor node metastasis restaging in patients with locally advanced rectal cancer after neoadjuvant chemoradiotherapy

“…)uN-staging [15, 16]uN+, the lymph node appears as circular or elliptic with clear margin; low echo or heterogeneous echoes (which is similar to the echoes of primary tumors); and short diameter >5 mmuN0, no lymph nodes, or lymph nodes that did not meet the above descriptions. …”