| 1. |
- Suzuki, Chikako, et al.
(författare)
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The importance of rectal cancer MRI protocols on interpretation accuracy
- 2008
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Ingår i: World Journal of Surgical Oncology. - : Springer Science and Business Media LLC. - 1477-7819. ; 6, s. 89-
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Magnetic resonance imaging (MRI) is used for preoperative local staging in patients with rectal cancer. Our aim was to retrospectively study the effects of the imaging protocol on the staging accuracy. PATIENTS AND METHODS: MR-examinations of 37 patients with locally advanced disease were divided into two groups; compliant and noncompliant, based on the imaging protocol, without knowledge of the histopathological results. A compliant rectal cancer imaging protocol was defined as including T2-weighted imaging in the sagittal and axial planes with supplementary coronal in low rectal tumors, alongside a high-resolution plane perpendicular to the rectum at the level of the primary tumor. Protocols not complying with these criteria were defined as noncompliant. Histopathological results were used as gold standard. RESULTS: Compliant rectal imaging protocols showed significantly better correlation with histopathological results regarding assessment of anterior organ involvement (sensitivity and specificity rates in compliant group were 86% and 94%, respectively vs. 50% and 33% in the noncompliant group). Compliant imaging protocols also used statistically significantly smaller voxel sizes and fewer number of MR sequences than the noncompliant protocols CONCLUSION: Appropriate MR imaging protocols enable more accurate local staging of locally advanced rectal tumors with less number of sequences and without intravenous gadolinium contrast agents.
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| 2. |
- Torkzad, Michael R., et al.
(författare)
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MRI after preoperative radiotherapy for rectal cancer; correlation with histopathology and the role of volumetry.
- 2007
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Ingår i: European Radiology. - : Springer Science and Business Media LLC. - 0938-7994 .- 1432-1084. ; 17:6, s. 1566-1573
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Tidskriftsartikel (refereegranskat)abstract
- The objective is to assess if tumor size after radiotherapy in patients with rectal cancer can be assessed by a second magnetic resonance imaging (MRI), after radiotherapy prior to surgery and to correlate changes observed on MRI with findings at histopathology at surgery. Twenty-five patients with MRI before and after radiotherapy were included. Variables studied were changes in tumor size, T-staging and distance to the circumferential resection margin (CRM). RVs was measured as tumor volume at surgery (Vs) divided by tumor volume at the initial MRI (Vi) in percent. RVm was defined as the tumor volume at the second MRI (Vm) divided by Vi in percent. The ypT-stage was the same or more favorable than the initial MRI T-stage in 24 of 25 patients. The second MRI was not more accurately predictive than the initial MRI for ypT-staging or distance to CRM (p > 0.05). Vm correlated significantly to Vs, as did RVs to RVm, although the former was always smaller than the latter. Vm and RVm correlated well with ypT-stage (p < 0.001). Volumetry seems to correlate with ypT-stage after preoperative radiotherapy for resectable rectal cancer. The value of a second MRI after radiotherapy for assessment of distance to CRM and ypT-staging is, however, not apparent.
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| 3. |
- Torkzad, Michael R., et al.
(författare)
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Significance of mesorectal volume in staging of rectal cancer with magnetic resonance imaging and the assessment of involvement of the mesorectal fascia
- 2007
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Ingår i: European Radiology. - : Springer Science and Business Media LLC. - 0938-7994 .- 1432-1084. ; 17:7, s. 1694-1699
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Tidskriftsartikel (refereegranskat)abstract
- The aim was to study the influence of mesorectal volume, as estimated by magnetic resonance imaging (MRI), that is to be removed during total mesorectal excision (TME), on the accuracy of the first preoperative MRI of rectal cancer compared to histopathology, and its correlation to locoregional prognostic factors. A total of 267 rectal cancer patients from a multinational study (MERCURY or MRI equivalence study) had their mesorectal volume retrospectively estimated by researchers without knowledge of the assessments made by the radiologist or the pathologist. The evaluations made by the pathologist and the radiologist were then compared, including T- and N-staging, assessment of extent of extramural tumor invasion (the largest portion of the tumor beyond the muscularis propria or EMI) and distance to mesorectal fascia; the discrepancies in the results were correlated to the mesorectal volume. T- or N-staging accuracy by MRI and the difference between the EMI as measured by the pathologist and the radiologist were not dependent on individual mesorectal volume. There was no correlation between assessment of involvement of mesorectal fascia or local neighboring organs by MRI and histopathology with mesorectal volume. Mesorectal volume does not affect locoregional prognostic factors or the accuracy of local staging of rectal cancer.
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