Gadolinium-enhanced dynamic magnetic resonance imaging with endorectal coil for local staging of rectal cancer

Purpose  

The aim of this study was to evaluate the accuracy of dynamic gadolinium (Gd)-enhanced magnetic resonance imaging (MRI) with endorectal coil for assessing tumor invasion based on simple classification criteria.     

Magnetic resonance imaging of cervical carcinoma using an endorectal surface coil

Introduction

The objective of this trial is to investigate the diagnostic value of magnetic resonance imaging (MRI) with an endorectal surface coil for precise local staging of patients with histologically proven cervical cancer by comparing the radiological, clinical, and histological results.

Materials and methods

Women with cervical cancer were recruited for this trial between February 2007, and September 2010. All the patients were clinically staged according to the FIGO classification and underwent radiological staging by MRI that employed an endorectal surface coil. The staging results after surgery were compared to histopathology in all the operable patients.

Results

A total of 74 consecutive patients were included in the trial. Forty-four (59.5%) patients underwent primary surgery, whereas 30 (40.5%) patients were inoperable according to FIGO and underwent primary radiochemotherapy. The mean age of the patients was 50.6 years. In 11 out of the 44 patients concordant staging results were obtained by all three staging modalities. Thirty-two of the 44 patients were concordantly staged by FIGO and histopathological examination, while only 16 were concordantly staged by eMRI and histopathological examination. eMRI overstaged tumors in 14 cases and understaged them in 7 cases.

Conclusions

eMRI is applicable in patients with cervical cancer, yet of no benefit than staging with FIGO or standard pelvic MRI. The most precise preoperative staging procedure still appears to be the clinical examination.     

Prostate cancer: local staging with endorectal surface coil MR imaging

Endorectal surface coil magnetic resonance (MR) imaging was used to stage the local extent of prostate cancer in 22 patients. The endorectal coil images were acquired with a 10-12-cm field of view and a 4-mm section thickness. All pathologic specimens were reviewed by one pathologist. Endorectal surface coil MR imaging was 82% accurate in the differentiation of stage B from stage C cancer. One case was overestimated, and three cases were underestimated. The three underestimated cases consisted of two cases of microscopic capsular invasion and one case of minimal seminal vesicle invasion. In a comparison of retrospective, blinded readings of endorectal coil and body coil images, there was an average improvement in accuracy of 16% in staging prostate cancer with endorectal coil images.     

经直肠内线圈1H MRS对前列腺癌的诊断价值

目的:探讨1H MRS对前列腺癌的诊断价值.方法:经穿刺活检、手术病理证实的40例前列腺癌患者,行轴位高分辨T2WI和经直肠内线圈行1H MRS扫描,分析前列腺癌FSE T2WI及1H MRS的影像表现.结果:1H-MRS波谱分析测得前列腺癌区(choline Creation)/Citrate平均值为2.52±1.24,而周围正常前列腺组织的平均值为0.47±0.17,并具有显著统计学差异;FSE T2WI扫描检出29例前列腺癌,敏感度为72.5%,1H MRS检出了35例前列腺癌,敏感性为87.5%(P<0.01).结论:经直肠内线圈H MRS可对前列腺癌做出准确诊断,可用于前列腺癌的筛查.     

Magnetic resonance in the staging of renal carcinoma. The results compared with computed tomography in 42 cases]

In order to investigate the value of MRI in the staging of renal cell carcinoma and to compare the results of MRI and CT, the authors evaluated by means of MRI and CT 42 patients affected with renal cell carcinoma. All patients underwent surgery, and pathology of the surgical specimens was performed. A comparison was made between the surgical and pathologic data and MRI and CT results. Moreover, a comparative evaluation of MRI and CT findings was also made. From the comparison between pathologic data and CT and MRI results MRI was seen to have correctly staged 36 of 42 cases (85%), versus CT 33 of 42 cases (78%). Moreover, MRI proved to be superior to CT in evaluating venous involvement (stages III A and III C) and extra-fascial tumor spread (stage IVA). On the contrary, no significant differences were found between MRI and CT in the evaluation of perirenal involvement (stages I-II) and lymph node metastases (stage III B). MRI misdiagnosed 6 of 42 cases: 2 false negatives in evaluating extracapsular tumor spread, 1 false positive of mesenteric infiltration, 1 false positive of renal vein thrombosis, 1 false positive and 1 false negative in evaluating lymph node metastases. CT misdiagnoses (9 of 42 cases) were the same as those of MRI in 5 cases, while in the MRI false positive of renal vein thrombosis CT was correct. The extant 4 incorrect CT findings were: 2 false positive of renal vein thrombosis, 1 false negative of infiltration of diaphragm and psoas muscle, 1 false positive infiltration of the right liver lobe. As yet, therefore, MRI cannot be routinely employed to stage all renal cancer patients. On the contrary, MRI should be considered as a second-choice diagnostic tool to employ in selected cases when CT alone cannot solve all the problems relative to staging.     

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.     

3-T MRI with phased-array coil in local staging of prostatic cancer

RATIONALE AND OBJECTIVES: To evaluate the diagnostic accuracy of a 3-T magnetic resonance imaging (MRI) system with a phased-array coil (3T MRI) in the local staging of prostatic cancer. MATERIALS AND METHODS: Between July 2004 and September 2007, 59 patients (mean age 66 years) with a histologic diagnosis of prostatic cancer underwent 3-T MRI with a phased-array coil. A total of 42/59 patients underwent a radical prostatectomy within 3 weeks of the MRI examination. Two radiologists with differing experience in the interpretation of prostatic imaging used a 1-5 scale score to assess extracapsular spread, seminal vesicle and neurovascular bundle infiltration, and prostatic apex involvement. The anatomopathologic examination conducted on histologic macrosections was the reference test used to evaluate the results of 3-T MRI. Interobserver reliability was assessed using the k value. RESULTS: The sensitivity, specificity, and accuracy values obtained by the expert radiologist were 68%, 92%, and 83%, respectively, compared to 50%, 85%, and 71% for the identification of extracapsular spread and 81%, 62%, and 84% compared to 63%, 50%, and 55% for apex involvement. Interobserver reliability was good (k = 0.71). Seminal vesicle infiltration was correctly identified in four of five cases and neurovascular bundle infiltration was identified in four of four cases. CONCLUSIONS: Despite presenting diagnostic accuracy values lower than those reported in literature using 1.5-T endorectal coil MRI, the use of 3-T MRI with a phased-array coil could constitute a valid alternative to MRI techniques using endorectal coils in selected patients. Direct comparative studies between the two methods on large caseloads are required to confirm this hypothesis.     

Local staging of prostate carcinoma with endorectal coil MRI: correlation with whole-mount radical prostatectomy specimens

The purpose of this study was to investigate the accuracy of endorectal coil MRI in the local staging of prostate carcinoma. A total of 73 patients with biopsy-proven prostate carcinoma were examined at 0.5 T prior being submitted to radical prostatectomy. The gold standard was provided in all patients by findings at whole-mount sectioning of the surgical specimens. At pathology 28 patients had stage T2, 30 had stage T3a/b, and 15 had stage T3c lesions. Overall accuracy of endorectal coil MRI in defining local tumor stage was 82% (60 of 73 patients). Of 73 patients, 5 (7%) were underestimated and 8 (11%) overestimated. The sensitivity and the specificity of endorectal coil MRI in diagnosing capsular penetration were 95% and 82%, respectively. Seminal vesicle invasion was detected with 80% sensitivity and 93% specificity. Our data indicate that endorectal coil MRI is an accurate method for local staging of prostate cancer.Correspondence to: C. Bartolozzi     

Magnetic resonance in the staging of multiple myeloma]

The authors retrospectively reviewed the MR examinations of 46 patients with clinical and laboratory findings of monoclonal gammopathies (MG). All cases had been submitted to radiographic examination which had shown skeletal involvement in 22 cases and osteoporosis in 11, with rupture of the vertebral body in 3 patients. Scintigraphy had been performed on all patients and CT on 12; 36 patients were subsequently submitted to follow-up (at 6, 12 and 24 months). MR examinations were performed with dedicated coils and standard sequences for the subjects with skeletal localizations on X-ray images. The extant cases, with no radiographic evidence of skeletal involvement, were submitted to MRI of the spine, skull and pelvis. In agreement with clinical and laboratory findings and with follow-up results (in 36 patients), MRI diagnosed MG with no skeletal involvement in 13 cases, osteoporosis in 8 (with rupture of the vertebral body in 2), asymptomatic non-progressive myeloma in 4, solitary myeloma in 3, and multiple myeloma in 18 cases. The good identification of bone marrow and its multiplanarity make MRI the method of choice in the study of patients with suspected or known gammopathies. If compared with other modalities, MRI is more sensitive and accurate in depicting the tumor, its size and relationship to periskeletal tissues, and its possible multifocality. Moreover, the technique has proven to be a valid tool during the follow-up, showing tumor response to therapy.     

Comparison of the digital rectal examination,endorectal ultrasound,and body coil magnetic resonance imaging in the staging of adenocarcinoma of the prostate

A series of 25 patients with biopsy proven adenocarcinoma of the prostate underwent preoperative staging evaluation with a digital rectal examination, endorectal ultrasound, and body coil magnetic resonance imaging (MRI) before their radical retropubic prostatectomy. The sensitivity and specificity of the digital rectal examination for the detection of extracapsular disease were 17 and 100%, respectively. The sensitivity and specificity of endorectal ultrasound for the detection of extracapsular disease were 35 and 89%, respectively. The sensitivity and specificity of body coil MRI for the detection of extracapsular disease by adenocarcinoma of the prostate were 47 and 63%, respectively. Microscopic disease of the capsule and seminal vesicles was the principle reason for understaging by both imaging modalities. This small series suggests that both imaging modalities are marginally more sensitive, albeit less specific, for extracapsular disease of the prostate than the digital rectal examination, with ultrasound having a slight edge in specificity and MRI having a slight edge in sensitivity.     

Comparison of the digital rectal examination, endorectal ultrasound, and body coil magnetic resonance imaging in the staging of adenocarcinoma of the prostate

A series of 25 patients with biopsy proven adenocarcinoma of the prostate underwent preoperative staging evaluation with a digital rectal examination, endorectal ultrasound, and body coil magnetic resonance imaging (MRI) before their radical retropubic prostatectomy. The sensitivity and specificity of the digital rectal examination for the detection of extracapsular disease were 17 and 100%, respectively. The sensitivity and specificity of endorectal ultrasound for the detection of extracapsular disease were 35 and 89%, respectively. The sensitivity and specificity of body coil MRI for the detection of extracapsular disease by adenocarcinoma of the prostate were 47 and 63%, respectively. Microscopic disease of the capsule and seminal vesicles was the principle reason for understaging by both imaging modalities. This small series suggests that both imaging modalities are marginally more sensitive, albeit less specific, for extracapsular disease of the prostate than the digital rectal examination, with ultrasound having a slight edge in specificity and MRI having a slight edge in sensitivity.     

Magnetic resonance imaging in the staging of renal cell carcinoma

A prospective study has been carried out to examine the role of magnetic resonance imaging (MRI) in the investigation of renal cell carcinoma in 24 patients. In all cases the inferior vena cava (IVC) was well demonstrated with MRI. In 14 out of 15 patients where surgical correlation was available, the MRI and operative staging were in agreement. Magnetic resonance imaging and computed tomographic (CT) staging were in agreement in 16 out of the 17 patients where both were performed. In one case, CT suggested hepatic invasion but this was found not to be present on MRI and at operation. Magnetic resonance imaging also provided substantial additional information in three patients, including two cases where MRI demonstrated a patent IVC that appeared occluded on CT (one of which also had vertebral metastases seen on MRI but missed on CT) and one case where CT failed to demonstrate minimal involvement of the IVC. Magnetic resonance imaging is an accurate means of staging renal cell carcinoma with clear advantages over CT. In no case in this series was inferior vena cavography found to be necessary.     

Magnetic resonance imaging, computed tomography and endosonography in the local staging of carcinoma of the cervix

Thirty-seven patients with carcinoma of the cervix were prospectively staged by examination under anaesthesia (EUA), transvaginal and transrectal ultrasound, computed tomography (CT) and magnetic resonance imaging (MRI). Pathological correlation was available for 20 patients. In the pathologically staged patients, EUA agreed with the staging in 17, understaging three patients. Endosonography agreed with the staging in 19, CT in 16 and MRI in 18 patients. For the remaining 17 patients, endosonography agreed with the EUA findings in 13, CT in 12 and MRI in 12. This study has shown that endosonography and MRI are more accurate than CT in the local staging of carcinoma of the cervix. Computed tomography was least accurate in staging early tumours and differentiating between Stage Ib and IIb disease. Lymph node involvement was detected with equal frequency by both CT and MRI. Magnetic resonance imaging was useful in identifying vaginal and bladder wall involvement and in one patient showed features due to an unsuspected early pregnancy.     

Magnetic resonance imaging in staging of renal cell carcinoma

From this preliminary study, the authors conclude that MRI adds little to the diagnosis of renal cell carcinoma, but may be very helpful in staging it.     

Magnetic resonance imaging for local staging of gastric carcinoma: results of an in vitro study

OBJECTIVE: Preoperative staging of gastric carcinoma is limited by the fact that available imaging modalities do not enable accurate evaluation of the depth of infiltration of the gastric wall. The aim of this study was to evaluate the efficiency of conventional magnetic resonance imaging (MRI) in local staging of gastric carcinoma. METHODS: Sixty-five specimens of patients with proven gastric carcinoma were examined immediately after gastrectomy. Examination was performed with a 1-T MRI and included T1-weighted, T2-weighted, and opposed phase images. Images were analyzed for the number of visible wall layers and their signal intensity characteristics, for tumor localization and depth of infiltration. T-stage was classified according to the TNM system. Finally, the staging by MRI was compared with the histopathological staging of the specimens. RESULTS: The mucosal, submucosal, and proper muscle layers could be differentiated by the typical signal intensities. Depiction of the subserosa or serosa was not possible. In 65 specimens, 67 carcinomas were found by the pathologist. Sixty-four of 67 (96%) histologically proven carcinomas were correctly localized by MRI; T-staging accuracy was 50% only, mainly because of overstaging pT2 tumors as T3. CONCLUSIONS: MRI enables differentiation of gastric wall layers and, therefore, technically allows the evaluation of the local tumor stage of gastric carcinomas. However, infiltration of the subserosal and serosal layer cannot be proved accurately. Overstaging pT2 tumors is one of the most predominant problems. Yet further technical developments in high-resolution imaging of the gastric wall may improve T-staging in the near future and overcome today's staging limitations.     

Comparison of phased-array 3.0-T and endorectal 1.5-T magnetic resonance imaging in the evaluation of local staging accuracy for prostate cancer

OBJECTIVE: To retrospectively evaluate local staging accuracy for prostate cancer at 3.0-T magnetic resonance imaging (MRI) by comparing with that at 1.5-T MRI. METHODS: Two groups, each consisting of 54 patients, were included by matching for age, prostate specific antigen, and Gleason score. Before radical prostatectomy, 1 group underwent 3.0-T MRI using a phased-array coil, and the other 1.5-T MRI using an endorectal coil. T2-weighted MR images at 3.0 and 1.5 T were analyzed in consensus by 2 radiologists, and their staging accuracy was compared with histology. Artifact and overall image quality were compared at both 3.0 and 1.5 T. RESULTS: Accuracy for T3 stage at 3.0 and 1.5 T were 72% (39/54) and 70% (38/54), respectively (P > 0.05). The 3.0-T MRI had a lower incidence of MR artifacts than the 1.5-T MRI (P < 0.05). However, overall imaging quality at both 3.0 and 1.5 T had no significant difference (P > 0.05). CONCLUSIONS: The 3.0-T phased-array MRI is equivalent to the 1.5-T endorectal MRI in evaluating local staging accuracy for prostate cancer without significant loss of imaging quality.