Preoperative assessment of the extension of rectal carcinoma: correlation of MR, surgical, and histopathologic findings

Nineteen patients with rectal carcinoma were evaluated prospectively. The extent of tumor and the relationship of the tumor to the levator ani muscle were studied as this determines the choice of the surgical procedure (abdominoperineal resection versus low anterior resection). Peroperative assessment and detailed evaluation of the pathologic specimens were correlated with magnetic resonance (MR) features. Magnetic resonance staging and surgical findings were at variance in four of 15 cases (27%). Magnetic resonance had sensitivities and specificities of 75 and 100% in the detection of perirectal growth. Magnetic resonance demonstrated invasion of adjacent pelvic side wall and sacrum in two of two cases. The comparison with TNM classification demonstrated that MR correctly staged 15 of 19 cases (79%). This study shows that MR is a good examination to evaluate the involvement of perirectal fatty tissues and adjacent structures. The low prevalence of involved lymph nodes in our cases prevents significant positive predictive values. Nevertheless, MR can help to select patients for local excision or for preoperative radiotherapy.     

CT and MR imaging in staging bladder neoplasms

Thirteen patients with bladder carcinoma were examined by magnetic resonance (MR) imaging and CT to determine the relative accuracy of the modalities in staging bladder carcinoma. Magnetic resonance correctly identified the presence or absence of extravesical spread of carcinoma in 10 of 13 patients (77%). Two patients were understaged and one was overstaged. Computed tomography correctly staged nine of 13 patients (69%), with three patients understaged and one patient overstaged. Neither MR nor CT was able to determine depth of invasion of the bladder wall in the absence of extravesical spread.     

Magnetic resonance imaging in suspected rectal cancer: determining tumor localization, stage, and sphincter-saving resectability at 3-Tesla-sustained high resolution

Purpose: To assess image quality and overall accuracy of 3-Tesla (3T)-sustained high-resolution magnetic resonance (MR) imaging for diagnostic preoperative workup in suspected rectal carcinoma.

Material and Methods: Twenty-three patients with suspected rectal cancer underwent unenhanced and contrast-enhanced fat-suppressed pelvic high-resolution MR imaging using a four-channel phased-array pelvic coil at 3T. Image quality, tumor stage, distance from the anorectal margin, and sphincter-saving resectability were prospectively assessed by two blinded readers. The results were correlated with clinical, surgical, and histopathologic findings.

Results: In all 23 patients, MR images were of diagnostic quality, and malignancy was correctly identified in 21 patients. The accuracy for determining sphincter-saving resectability was 100% (19/19). T stage and N stage were correctly diagnosed in 95% and 91%, respectively. MRI allowed correct identification of tumor extension and its relation to surgically relevant pelvic structures including the anorectal margin and mesorectal fascia. Transverse T2-weighted fast spin-echo images compared superiorly to all other sequences for the diagnosis of mesorectal infiltration and lymph node involvement. Moreover, transverse fat-suppressed contrast-enhanced T1-weighted images were valuable for identifying tumor infiltration, while sagittal sections were useful for the detection of longitudinal tumor extension.

Conclusion: MR imaging with phased-array receiver coils at 3T facilitated both visualization of different pathologic conditions of the rectum and accurate determination of tumor stage in rectal carcinomas. Thus, this noninvasive diagnostic approach appeared highly suitable for the assessment of patients with suspected rectal carcinoma.     

MR staging of bladder carcinoma: correlation with pathologic findings

Forty patients with bladder carcinoma were examined preoperatively by means of magnetic resonance (MR) imaging. In all patients, total cystectomy with enterocystoplasty and pelvic node dissection was performed. The surgical and pathologic findings were correlated with the MR findings. Extension through the deep muscle of the bladder wall was present in 20 of the 40 patients and was diagnosed with a sensitivity of 95% and a specificity of 95%. Extension to perivesical fat was present in 18 of 40 patients and was diagnosed with a sensitivity of 66% and a specificity of 100%. Invasion of the adjacent organs was present in nine of 40 patients and was diagnosed with a sensitivity of 44% and a specificity of 96%. On the basis of the MR findings, the tumor was correctly staged, according to the TNM classification, in 24 of 40 (60%) patients, tumor extension was overestimated in three of 40 (7.5%) patients, and tumor extension was underestimated in 13 of 40 (32.5%) patients. MR imaging has been shown to be accurate in identification of macroscopic lymph node involvement and deep muscle involvement. It appears to be at least as useful as computed tomography (CT) in the evaluation of perivesical fat involvement and to be superior to CT in the detection of invasion of adjacent organs. One limitation of MR imaging is in the evaluation of tumor extension into the periurethral glands.     

Rectal carcinoma: staging at MR imaging with endorectal surface coil. Work in progress

To increase the accuracy of local staging of rectal carcinomas at magnetic resonance (MR) imaging, the authors placed on endorectal coil mounted on a balloon in a position adjacent to the lesion. Use of such a local coil resulted in increased signal-to-noise ratio compared with use of a body coil; higher-resolution images were obtained because the field of view was decreased. The depth of wall invasion by rectal carcinoma was correctly staged with endorectal MR imaging in 11 of 12 patients. In the detection of perirectal adenopathy, use of MR enabled correct identification of positive perirectal nodes in four of seven patients (57%). There were no false-positive diagnoses of perirectal adenopathy at MR. Endorectal MR imaging is an evolving and promising technique for the local staging of rectal carcinomas, but further studies are needed to demonstrate its efficacy.     

Rectal carcinoma: CT staging with water as contrast medium

Computed tomography (CT) was used to study 42 patients with rectal carcinoma. Water was used as a contrast medium for studying the local extent of tumor in all patients. Scans were read prospectively without knowledge of the histologic staging and then compared with pathologic specimens. CT depicted the tumor in all patients. Comparison of CT and histologic results (following the Dukes classification) showed that disease was correctly staged as A in three of four patients, as B in eight of 12, as C in 15 of 17, and as D in nine of nine. Overall, carcinoma was correctly staged with CT in 35 of 42 patients (diagnostic accuracy, 83.3%). The accuracy in the assessment of local invasion was 97.6% (41 of 42). In the detection of lymph node involvement, the accuracy was 78.6% (sensitivity, 88%; specificity, 64.7%). CT is recommended in the preoperative staging of rectal carcinoma and as an aid in choosing the appropriate therapy. The use of water enema and complete distention of the rectum are reliable techniques for improving the accuracy of CT in the assessment of local invasion by cancer.     

Renal cancer staging: Comparison of contrast-enhanced CT and gadolinium-enhanced fat-suppressed spin-echo and gradient-echo MR imaging

Fifty-three consecutive patients with 61 solid or complex non-fat-containing renal masses compatible with renal cancer were examined with contrast-enhanced computed tomography (CT) and magnetic resonance (MR) imaging with pre- and postcontrast FLASH (fast low-angle shot) and fat-suppressed spin-echo sequences. CT and MR imaging were performed within a 1-month interval. CT and MR images were prospectively interpreted. Tumor detection and staging were determined in all patients. CT and MR imaging enabled detection of 54 and 58 of 61 renal tumors, respectively. CT and MR imaging showed 34 and 35 of 38 histologically proved renal tumors, respectively, in 31 patients. Tumor size on CT and MR images demonstrated good correlation and correlated well with the size of pathologic specimens of 34 of 38 resected tumors detected with CT and MR imaging (r =.99). Of the 31 tumors in 31 patients who underwent surgical resection, 24 were correctly staged with CT and 29 with MR imaging. CT and MR imaging both enabled correct staging of four of five additional tumors with biopsy proof of tumor stage. A moderate difference in staging was observed between CT and MR imaging (P =.05). CT showed 13 and MR imaging 15 of 15 tumor thrombi. CT and MR imaging both showed 11 of 11 cases of adenopathy. The results suggest that MR imaging is moderately better than CT for the detection and staging of renal cancer.     

Preoperative and postoperative CT staging of rectosigmoid carcinoma

This study reports a 4 year experience using CT for preoperative staging and for evaluation of patients with rectal and sigmoid carcinoma after surgery. All patients were evaluated on a GE 8800 scanner using 1 cm contiguous slices. Only 15 of the 25 preoperative patients were staged correctly. The other 10 patients were understaged by CT. The accuracy of detecting local invasion was 70%, but only seven (35%) of 20 patients had accurate assessment of lymph nodes. The overall accuracy of CT staging in the 46 postoperative patients was 87%, with a sensitivity of 91% and a specificity of 72%. Most recurrences were found in the pelvis; 16 patients had liver metastases, and metastatic disease obstructing the ureters was detected in eight patients. On the basis of these results, it was concluded that CT should not be used routinely to preoperatively stage patients with rectosigmoid carcinoma. However, all patients who have undergone resection for rectal or sigmoid carcinoma should have aggressive CT evaluation including a baseline study at 2-4 months and then follow-up studies at every 6 months for at least 2 years. All new or enlarging masses should have CT-guided biopsies. This approach may prolong survival by detecting early asymptomatic recurrences.     

Integrated PET/CT in the preoperative staging of lung cancer: A prospective comparison of CT,PET and integrated PET/CT

Purpose

The purpose of this study was to evaluate the role of integrated PET/CT in the staging of lung cancer compared with CT alone or PET alone.

Materials and methods

Thirty-three patients underwent integrated PET/CT for the staging of lung cancer. The tumor, node and metastasis (TNM) stages were assessed with CT, PET and integrated PET–CT and compared with the surgical and pathological staging.

Results

CT correctly evaluated the (T) status in (64%) of the patients, PET in (59%) and PET/CT in (86%). CT correctly evaluated the (N) status in (73%) of the patients, PET in (76%), and PET/CT (88%) with accuracy, sensitivity, specificity, PPV and NPV were 73%, 78%, 71%, 50% and 94% for CT, 76%, 67%, 79%, 55% and 95% for PET and 88%, 89%, 88%, 73% and 100% for PET/CT respectively, and for (M) status were 91%, 86%, 92%, 75% and 96% for CT, 88%, 71%, 92%, 71% and 92% for PET and 97%, 100%, 96%, 88% and 100% for PET/CT respectively. Regarding the overall TNM staging CT correctly staged 24 patients. PET correctly staged 23 cases while PET/CT correctly staged 30 cases. A significant difference in the accuracy of overall tumor staging between PET/CT and CT (P = 0.0412) or PET (P = 0.0233).

Conclusion

The integrated PET/CT is superior to either CT or PET in the staging of lung cancer which has an important impact on selection of the appropriate treatment regimen.     

Prospective comparison of helical CT and MR imaging in clinically suspected acute pulmonary embolism

The purpose of this study is to compare sensitivity and specificity of helical CT and MR imaging for detecting acute pulmonary embolism (PE). Patients who were suspected clinically of having PE were randomly assigned to undergo either helical contrast-enhanced CT or gradient-echo MR (if one modality was contraindicated, the patient was assigned to the other). Patients were considered to have PE if they had: (1) high-probability V-Q scan and high clinical probability of PE; or (2) pulmonary angiogram positive for PE. Patients were considered not to have PE if they had either: (1) normal V-Q scan; (2) low probability V-Q scan and low clinical probability of PE; or (3) pulmonary angiogram negative for PE. The CT and MR images were read randomly and independently by five radiologists with varying levels of CT and MR experience. Twenty eight patients underwent CT and 25 MR. A total of 21 patients underwent pulmonary angiography (6 had PE, 15 did not have PE). Of the other 32 patients, 15 had high probability scan/high clinical probability and 17 had low probability scan/low clinical probability. For the five observers, the average sensitivity of CT was 75% and of MR 46%; the average specificity of CT was 89% and of MR 90%. Experience with vascular MR and enhanced CT influenced diagnostic accuracy. For the two vascular MR experts, average sensitivity and specificity of MR were 71% and 97%, and of CT 73% and 97%. In this pilot study, when CT and MR were interpreted with comparable expertise, they had similar accuracy for detecting pulmonary embolism.     

MR imaging of rectal cancer before and after chemoradiation therapy

PURPOSE: This study was done to determine the diagnostic accuracy of magnetic resonance (MR) imaging in patients with rectal carcinoma by comparing post-chemoradiation MR imaging with pathological specimens. MATERIALS AND METHODS: We enrolled 39 patients with locally advanced rectal cancer. All patients received chemoradiation therapy before surgery and neoadjuvant chemoradiation therapy followed by MR imaging. MR images were analysed by a team of two expert radiologists unaware of the clinical and histopathological findings. RESULTS: Following neoadjuvant chemoradiation therapy, the analysis of MR images showed 23 (59%) patients with a rectal disease staged ≤T2 and 16 (41%) with a disease staged >T2. Post-treatment histological staging (TNM) revealed 13 patients with a disease >T2 and 26 patients with a disease ≤T2. Cohen's kappa to measure concordance between post-chemoradiation MR staging and histological response showed 83.6% concordance for disease confined to the serosa (≤T3): concordance was 97.22% for disease ≤N1 and 33.33% for disease >N1. CONCLUSIONS: MR imaging is critical for discovering T3 disease; moreover, morphological MR imaging does not always provide the opportunity to discern small residual cancer cells hidden in fibrotic tissue that could cause involvement of circumferential resection margin (CRM) on histology.     

Effect of using endorectal coil in preoperative staging of rectal carcinomas by pelvic MR imaging

PURPOSE: To assess the accuracy of magnetic resonance imaging with pelvic phased-array and endorectal coils prospectively, and evaluate if endorectal coil provides any additional information to high resolution pelvic MR imaging in rectal carcinoma staging. MATERIALS AND METHODS: Preoperative MRI of 25 patients with rectal carcinoma was performed with pelvic phased-array coil alone, and with both phased-array coil and endorectal coil placed. Staging was made by evaluating images obtained by using both coils prospectively, and correlated with histopathologic staging. The images were then assessed separately, and compared to each other retrospectively. RESULTS: Two and 3 of the 5 histopathologically proved T1 tumors were staged correctly on MRI with pelvic phased-array coil alone and after the endorectal coil placement, respectively. Histopathologically identified five T2 tumors were staged correctly as T2 in 4 of the cases, 1 was understaged and 10 of 14 patients who had T3 tumor were staged as T3, 4 of them were understaged as T2 on both techniques. Specificity, sensitivity and accuracy rates for staging of T3 tumors were found as 71%, 100% and 84%, respectively, for each technique. Sensitivity and positive predictive value of N staging were both 88% on both techniques. CONCLUSION: Pelvic MR imaging after the placement of endorectal coil in addition to the phase-array coil was not superior to the imaging with phased-array coil alone in T staging of rectal carcinomas and the latter achieved better visualization of the lymph nodes by means of larger field of view.     

Results of computed tomographic diagnosis of recurrences of colorectal cancer

Postoperative CT was performed in 179 colo-rectal carcinoma patients who had undergone abdominoperineal extirpation (n = 71), resection and rectosigmoid anastomosis (n = 37), hemicolectomy (n = 32), resection of sigma (n = 31), and others (n = 8). Normal CT-findings were found in 25% only, in more than 75% of all cases pathological CT-findings were seen. CT detected local recurrence in 87 patients. Based on CT findings local recurrent colo-rectal carcinoma was classified as Stage 0, or intraluminal mass, in 2 patients (2%). Stage 1, or extraluminal mass without invasion of adjacent organs, was found in 38 (44%) patients; Stage 2 a, tumor mass with direct invasions of adjacent organs but not the pelvic side walls could be demonstrated in 13 (15%) of the cases; Stage 2 b, or extension of mass to pelvic side walls, and Stage 3, or distant metastatic disease, was found in 14 (16%) and 20 (23%) patients. CT was negative in 2 patients with local recurrence (beside Stage 0), an incorrect diagnosis of recurrence due postoperative scarring was found in 4 patients. CT detected exclusive also metastatic disease of the liver in 23 patients and intraabdominal lymph node involvement in 8 patients.     

Rectal cancer: MR imaging in local staging--is gadolinium-based contrast material helpful?

PURPOSE: To determine retrospectively whether addition of gadolinium-enhanced T1-weighted magnetic resonance (MR) sequence to T2-weighted turbo spin-echo (SE) MR imaging is valuable for preoperative assessment of T stage and circumferential resection margin in patients with primary rectal cancer. MATERIALS AND METHODS: Local institutional review board approved study and waived informed patient consent. Eighty-three patients with operable primary rectal cancer underwent preoperative MR imaging. Retrospectively, two observers independently scored T2-weighted turbo SE MR images and, in a second reading, T2-weighted images combined with gadolinium-enhanced T1-weighted turbo SE MR images for tumor penetration through rectal wall and tumor extension into mesorectal fascia. A confidence level scoring system was used, and receiver operating characteristic (ROC) curves were generated. Histologic findings were standard of reference. Difference in performance of T2-weighted and combined T2-weighted plus gadolinium-enhanced T1-weighted sequences was analyzed by comparing corresponding areas under ROC curves (A(z)) for each observer. Interobserver agreement was calculated by using linear weighted kappa statistics. RESULTS: Addition of contrast-enhanced T1-weighted to T2-weighted MR imaging did not significantly improve diagnostic accuracy for prediction of tumor penetration through rectal wall (A(z) of T2-weighted vs T2-weighted plus T1-weighted images for observer 1, 0.740 vs 0.764; observer 2, 0.856 vs 0.768) and tumor extension into mesorectal fascia (A(z) for observer 1, 0.962 vs 0.902; observer 2, 0.902 vs 0.911). Diagnostic performance (A(z)) of MR and interobserver agreement were high for prediction of tumor extension into mesorectal fascia (kappa = 0.61, 0.74) but only moderate for penetration through rectal wall (kappa = 0.47, 0.45). CONCLUSION: Gadolinium-enhanced MR sequences did not improve diagnostic accuracy for assessment of tumor penetration through rectal wall and tumor extension into mesorectal fascia.     

Comparison of transrectal sonography and double-contrast MR imaging when staging rectal cancer

OBJECTIVE: The aim of this study was the prospective comparison of the diagnostic yield of transrectal sonography and double-contrast MR imaging for preoperative staging of rectal cancer. SUBJECTS AND METHODS. Thirty-nine rectal cancer patients (20 men, 19 women) underwent transrectal sonography performed with a 10-MHz endoanal probe and MR imaging (1.0 T or 1.5 T) using a whole-body coil. After rectal application of a superparamagnetic iron oxide MR contrast agent, T1- and T2-weighted images and gadolinium-enhanced double-contrast images were obtained. The results of examinations were compared with the histology of resected specimens. RESULTS: Histopathology showed four stage T1, 11 stage T2, 18 stage T3, and six stage T4 tumors using the TNM staging system. Nodal metastases were seen in 16 patients. Transrectal sonography could not be performed in 11 patients because of the high location of the tumor. In the remaining 28 patients, the accuracy of transrectal sonography for T stage was 64% overall (patients not receiving radiation, 69%; patients receiving radiation, 60%) and 70% for N stage. In 39 patients, double-contrast MR imaging correctly identified the T stage with an accuracy of 64% overall (patients not receiving radiation, 75%; patients receiving radiation, 53%) and the N stage with an accuracy of 62%. The assessment of rectal wall penetration (Dukes' classification A versus B) revealed a sensitivity, specificity, and accuracy of 93%, 71%, and 82%, respectively, for transrectal sonography and 100%, 60%, and 85% for MR imaging. CONCLUSION: If it is technically feasible, transrectal sonography is an accurate method for staging rectal cancer. In proximal or stenotic tumors, double-contrast MR imaging is the method of choice. Diagnostic accuracy of transrectal sonography and MR imaging is high for predicting bowel wall penetration.     

Primary malignant fibrous histiocytoma of the chest wall: CT and MR appearance

PURPOSE: The purpose of this work is to describe the CT and MR appearance of primary malignant fibrous histiocytoma (MFH) of the chest wall. METHOD: Eleven men and eight women (45-76 years old) with primary MFH of the chest wall who underwent both CT and MRI were enrolled, and the imaging interpretation was retrospectively compared to the pathologic specimen. RESULTS: All tumors were inhomogeneous in appearance on CT scans. All tumors showed high signal intensity on T2-weighted images. On T1-weighted MR images, tumors displayed inhomogeneous isosignal intensity in 15 cases (79%) and low signal intensity in 5 (21%) compared with the surrounding muscle. Tumors exhibited inhomogeneous enhancement in all except three localized tumors on enhanced CT and MRI. Invasion of intercostal muscle was noted on MR images in 18 patients (95%) and on CT in 11 patients (58%). CONCLUSION: There might be various radiologic appearances of MFH. However, CT and MRI are able to demonstrate the exact localization and disease extent of MFH arising in the chest wall.     

直肠癌低位前切除Proximate~与GF-1管状吻合器吻合临床对比研究

目的探讨不同吻合器对直肠癌低位前切除术吻合口的影响。方法回顾性分析比较209例直肠癌低位前切除采用Proximate与GF-1管状吻合器吻合病例资料。结果采用Proximate管状吻合器吻合残端完整100例,吻合口复发1例,GF-1管状吻合器吻合残端完整71例,吻合口复发7例,两组差异显著;手术时间、临时性粪便转流、吻合口漏、吻合口狭窄、吻合口出血两组无显著差异。结论在直肠癌低位前切除中采用管状吻合器吻合是安全可靠的,而Proximate管状吻合器使用更方便,优于GF-1管状吻合器。     

Preoperative locoregional staging of rectal carcinoma: comparison of MR, TRUS and Multislice CT. Personal experience

PURPOSE: The aim of this study was to measure the sensitivity and clinical indications of Magnetic Resonance (MR) as compared to Transrectal Ultrasonography (TRUS) and spiral Computed Tomography (CT) in the preoperative staging and evaluation of rectal carcinoma. MATERIALS AND METHODS: Twenty patients with histologically proven rectal carcinoma were examined with phased-array coil MRI. We used T1 and T2, spin-echo, turbo-spin-echo, flash2D sequences with and without fat suppression; FOV 180-280; 4-6 mm slice thickness; i.v. Gadolinium. The MR images were compared with TRUS, spiral CT and with the final histological diagnosis. RESULTS: MR showed a 92.3% sensitivity for rectal wall infiltration vs. 100% of TRUS and 75% of CT. The sensitivity for lymph node metastases was 76.4% vs. 72.2% for TRUS and 88% for CT. CONCLUSIONS: Locoregional staging of rectal cancer by MRI shows a high sensitivity and is also feasible in stenosing or proximal rectal lesions. TRUS, despite its limitations, is still the most sensitive method for the evaluation of wall infiltration. CT was less sensitive than the other two METHODS: The sensitivity of MR and CT for lymph node metastases is comparable, but the former is more specific.     

Crohn's disease evaluation: comparison of contrast-enhanced MR imaging and single-phase helical CT scanning

The purpose of this study was to evaluate the use of gadolinium and barium-enhanced magnetic resonance (MR) imaging in detecting intestinal and extraintestinal Crohn's disease and compare MRI with contrast-enhanced helical computed tomography (CT). Twenty-six patients with Crohn's disease underwent imaging examinations, including gadolinium-enhanced, fat suppressed fast multiplanar spoiled gradient-recalled (FMPSPGR) MR imaging with oral 2% barium sulfate and rectal water and with helical CT using i.v. and positive (13) or negative (13) intestinal contrast material. MR images and CT scans were reviewed separately by two radiologists for bowel wall thickness and enhancement, presence of abscess, phlegmon, and fistula. MR images and CT scans were then compared side by side. Surgical, endoscopic, and histopathologic findings and results of barium studies were reviewed to determine the location and severity of involvement of intestinal Crohn's disease. Depiction of mural thickening and/or enhancement was superior on the MR images, which showed 55 (85%) and 52 (80%) of 65 abnormal bowel segments for the two observers, compared with helical CT, which showed 39 (60%) and 42 (65%; P < 0.001, P < 0.05) of bowel segments affected by Crohn's disease. Segments of bowel with moderate or marked mural thickening were depicted equally on MR imaging and helical CT. In mildly diseased segments of bowel, with only slight thickening and enhancement, MR imaging depicted 22 (79%) and 19 (68%) of 28 segments, compared with helical CT, which depicted 9 (32%; P < 0.01), and 13 (46%; P > 0.05) of 28 segments. In the side-by side comparison, MR imaging was preferred over helical CT for depicting normal bowel wall (MR 71%, CT 4%, equal 25%; P < 0.001), mural thickening (MR 41%, CT 11% equal 48%; P < 0.01), mural enhancement (MR 89%, equal 11%; P < 0.001), and overall GI tract evaluation (MR 52%, CT 10%, equal 38%; P < 0.001). Gadolinium-enhanced MR imaging with oral dilute barium sulfate and rectal water depicts intestinal and extraintestinal changes of Crohn's disease and shows promise as a clinically useful tool.     

Contribution of MRI in the staging of cancer of the bladder. Apropos of 40 cases

56 patients with bladder carcinoma were examined by magnetic resonance in the pre-operative staging. In 40 patients where total cystectomy with enterocystoplasty and pelvic node dissection were performed, a good correlation with surgical and pathologic findings was obtained. MR examination using T1 (TR 400 ms, TE 28 ms) and T2 (TR 1,200-1,600 ms, TE 40 80 120 ms) weighted images in different planes where performed after biopsy of the bladder tumor through endoscopy and within 1 or 2 weeks before surgery. Neoplasms were characterized by site, size and growth pattern. Extension through the deep muscle of the bladder wall was correctly identified in 95% with a sensitivity of 95% and a specificity of 95%. Extension through perivesical fat was assessed accurately in 85% with a sensitivity of 66% and a specificity of 100%. Accuracy in evaluating invasion of adjacent organs was 85%, sensitivity 44%, specificity 96%. Lymphadenopathy has been accurately assessed in 97.5% with a sensitivity of 83% and a specificity of 100%. MR correctly staged the tumor according to TNM classification in 24/40 (60%) patients, overestimated the extension in 3/40 (7.5%) and underestimated the extension in 13/40 (32.5%).