Comparative Study Between the Role of Trans rectal Ultrasound and Magnetic Resonance Imaging in Preoperative Staging of Rectal Carcinoma (original) (raw)

Transrectal ultrasonography and magnetic resonance imaging in the staging of rectal cancer. Effect of experience

Scandinavian Journal of Gastroenterology, 2008

Objective. To evaluate the effect of experience on preoperative staging of rectal cancer using magnetic resonance imaging (MRI) and transrectal ultrasound (TRUS). Material and methods. From January 2002 to May 2006, 134 consecutive patients with biopsy-proven rectal cancer were examined with a 1.5-Tesla MRI unit and TRUS using a 6.5-MHz transducer. An experienced gastrointestinal radiologist (R1) or a general radiologist (R2) performed the evaluations. All patients (78 M, 56 F, mean age 69.1 years, range 38Á89) were treated with surgery alone. The mean size of the tumour was 4.0 cm (range 1.1Á7.5). A complete postoperative histopathological examination was used as the gold standard. Results. At pathology, 42 of 134 (31%) tumours were classified as T1-T2 and 92 (69%) were classified as T3-T4. The TRUS sensitivity in rectal tumour T-staging was 93% for R1 and 75% for R2 (pB0. 01); specificity was 83% for R1 and 46% for R2 (pB0.05). The MRI sensitivity in rectal tumour T-staging was 96% for R1 and 77% for R2 (pB0. 05); the specificity was 74% for R1 and 40% for R2 (pB0.05). There was no difference in the results of N-staging between R1 and R2 for either TRUS or MRI. Conclusion. Reader experience had a statistically significant positive effect on the preoperative prediction of tumour involvement of the rectal wall. To obtain high-quality preoperative prediction of rectal cancer T-stage, it is suggested that preoperative TRUS and MRI staging should be supervised by an expert in the colorectal cancer team. In addition to this supervision, the person responsible for staging should be trained through a defined training programme.

Comparison of CT and MRI in the pre-operative staging of rectal adenocarcinoma and prediction of circumferential resection margin involvement by MRI

Colorectal Disease, 2003

Objective It has been suggested that MRI may be used as the sole modality of choice in pre-operative staging in rectal cancers. Knowledge of tumour stage and a threatened Circumferential Resection Margin (CRM) pre-operatively are essential for planning neo-adjuvant therapy and as predictors of local recurrence. At present most units utilize CT scanning to assess these parameters. The aim of our study was two fold: firstly to examine the accuracy of preop CT and MRI staging of rectal cancers compared with final histology and secondly to assess the accuracy of MRI in predicting penetration of the mesorectal envelope (ME).

Preoperative staging of rectal cancer

Acta Oncologica, 2008

With the widespread introduction of preoperative radiotherapy for rectal cancer and the development of transanal endoscopic microsurgery for selected early lesions, preoperative radiological staging of these tumours has taken on increasing importance. This study is a systematic review to evaluate computed tomography (CT), endorectal sonography (ES) and magnetic resonance imaging (MRI) as preoperative staging modalities in rectal cancer. A Medline-based search identifying studies using CT, ES, or MRI in preoperative staging of rectal cancer between 1980 and 1998 was undertaken. The list of papers was supplemented by extensive cross-checking of citation lists. Studies were included if they met predetermined criteria. Data from the accepted studies were entered into pooled tables comparing radiological and pathological staging results for each modality both in determining bowel wall penetration and involvement of lymph nodes. Accuracy, sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio and negative likelihood ratio were determined for the pooled results. Eighty-three studies from 78 papers including 4897 patients met the inclusion criteria. In determining the wall penetration of the tumour the values for sensitivity for CT, ES, MRI and MRI with endorectal coil were 78%, 93%, 86% and 89%; for specificity 63%, 78%, 77% and 79%; and for accuracy 73%, 87%, 82% and 84%, respectively. In determining the nodal involvement by tumour the sensitivity values for CT, ES, MRI and MRI with endorectal coil 52%, 71%, 65% and 82%; for specificity 78%, 76%, 80% and 83%; and for accuracy 66%, 74%, 74% and 82%, respectively. MRI with an endorectal coil is the single investigation that most accurately predicts pathological stage in rectal cancer.

MRI of rectal carcinoma: Preoperative staging and planning of sphincter-sparing surgery

The Egyptian Journal of Radiology and Nuclear Medicine, 2014

Background: Rectal cancer constitutes about one-third of all gastrointestinal tract tumors. Because of its high recurrence rates reaching 30%, it is vitally important to accurately stage these tumors preoperatively, so that appropriate surgical resection can be undertaken. MRI is used to assist in staging, identifying patients who may benefit from preoperative chemotherapy-radiation therapy, and in surgical planning. Aim: To determine the accuracy of MRI in the preoperative staging and planning of surgical management of rectal carcinoma. Subjects and methods: Twenty-five patients (14 males, 11 females) with rectal carcinoma were included in this study. MRI scans were performed prior to surgery in all patients, on a 1.5T scanner, and images were evaluated by three experienced radiologists. Inter-observer agreement between the three radiologists and the correlation between the imaging findings, histopathology and operative findings were evaluated. Results: MRI findings were correctly predictive of T category in 21 cases (accuracy, 84%). In 19 (86.4%) of the 22 resectable cases, sphincter-sparing surgical approaches were accurately chosen on the basis of MRI findings. Conclusion: MRI of rectal cancer is accurate for prediction of tumor stage and the feasibility of sphincter-sparing surgery, which are the main factors affecting the outcome of surgery.

Comparative study for preoperative staging of rectal cancer

Diseases of the Colon & Rectum, 1989

Rectum 1989;32:53-56. A comparative study of preoperative evaluation of rectal cancer is presented. Sixty-eight patients with rectal cancer were examined digitally and by computerized tomography and transrectal ultrasound.

Endorectal ultrasonography versus phased-array magnetic resonance imaging for preoperative staging of rectal cancer

World Journal of Gastroenterology, 2008

AIM: To compare the diagnostic accuracy of pelvic phased-array magnetic resonance imaging (MRI) and endorectal ultrasonography (ERUS) in the preoperative staging of rectal carcinoma. METHODS: Thirty-four patients (15 males, 19 females) with ages ranging between 29 and 75 who have biopsy proven rectal tumor underwent both MRI and ERUS examinations before surgery. All patients were evaluated to determine the diagnostic accuracy of depth of transmural tumor invasion and lymph node metastases. Imaging results were correlated with histopathological findings regarded as the gold standard and both modalities were compared in terms of predicting preoperative local staging of rectal carcinoma. RESULTS: The pathological T stage of the tumors was: pT1 in 1 patient, pT2 in 9 patients, pT3 in 21 patients and pT4 in 3 patients. The pathological N stage of the tumors was: pN0 in 19 patients, pN1 in 9 patients and pN2 in 6 patients. The accuracy of T staging for MRI was 89.70% (27 out of 34). The sensitivity was 79.41% and the specificity was 93.14%. The accuracy of T staging for ERUS was 85.29% (24 out of 34). The sensitivity was 70.59% and the specificity was 90.20%. Detection of lymph node metastases using phased-array MRI gave an accuracy of 74.50% (21 out of 34). The sensitivity and specificity was found to be 61.76% and 80.88%, respectively. By using ERUS in the detection of lymph node metastases, an accuracy of 76.47% (18 out of 34) was obtained. The sensitivity and specificity were found to be 52.94% and 84.31%, respectively. CONCLUSION: ERUS and phased-array MRI are complementary methods in the accurate preoperative staging of rectal cancer. In conclusion, we can state that phased-array MRI was observed to be slightly superior in determining the depth of transmural invasion (T stage) and has same value in detecting lymph node metastases (N stage) as compared to ERUS.

Effectiveness of preoperative staging in rectal cancer: digital rectal examination, endoluminal ultrasound or magnetic resonance imaging?

British journal of cancer, 2004

In rectal cancer, preoperative staging should identify early tumours suitable for treatment by surgery alone and locally advanced tumours that require therapy to induce tumour regression from the potential resection margin. Currently, local staging can be performed by digital rectal examination (DRE), endoluminal ultrasound (EUS) or magnetic resonance imaging (MRI). Each staging method was compared for clinical benefit and cost-effectiveness. The accuracy of high-resolution MRI, DRE and EUS in identifying favourable, unfavourable and locally advanced rectal carcinomas in 98 patients undergoing total mesorectal excision was compared prospectively against the resection specimen pathological as the gold standard. Agreement between each staging modality with pathology assessment of tumour favourability was calculated with the chance-corrected agreement given as the kappa statistic, based on marginal homogenised data. Differences in effectiveness of the staging modalities were compared w...

Imaging in rectal cancer with emphasis on local staging with MRI

The Indian journal of radiology & imaging

Imaging in rectal cancer has a vital role in staging disease, and in selecting and optimizing treatment planning. High-resolution MRI (HR-MRI) is the recommended method of first choice for local staging of rectal cancer for both primary staging and for restaging after preoperative chemoradiation (CT-RT). HR-MRI helps decide between upfront surgery and preoperative CT-RT. It provides high accuracy for prediction of circumferential resection margin at surgery, T category, and nodal status in that order. MRI also helps assess resectability after preoperative CT-RT and decide between sphincter saving or more radical surgery. Accurate technique is crucial for obtaining high-resolution images in the appropriate planes for correct staging. The phased array external coil has replaced the endorectal coil that is no longer recommended. Non-fat suppressed 2D T2-weighted (T2W) sequences in orthogonal planes to the tumor are sufficient for primary staging. Contrast-enhanced MRI is considered ina...

MRI anatomy of the rectum: key concepts important for rectal cancer staging and treatment planning

Insights into Imaging

A good understanding of the MRI anatomy of the rectum and its surroundings is pivotal to ensure high-quality diagnostic evaluation and reporting of rectal cancer. With this pictorial review, we aim to provide an image-based overview of key anatomical concepts essential for treatment planning, response evaluation and post-operative assessment. These concepts include the cross-sectional anatomy of the rectal wall in relation to T-staging; differences in staging and treatment between anal and rectal cancer; landmarks used to define the upper and lower boundaries of the rectum; the anatomy of the pelvic floor and anal canal, the mesorectal fascia, peritoneum and peritoneal reflection; and guides to help discern different pelvic lymph node stations on MRI to properly stage regional and non-regional rectal lymph node metastases. Finally, this review will highlight key aspects of post-treatment anatomy, including the assessment of radiation-induced changes and the evaluation of the post-op...