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DW-MRI of the urogenital tract: applications in oncology.

Petralia G, Thoeny HC - Cancer Imaging (2010)

Bottom Line: Promising results were also published for the detection of prostate cancer.DW-MRI may improve the performance of conventional T2-weighted and contrast-enhanced MRI in the preoperative work-up of bladder cancer, as it may help in distinguishing superficial from muscle invasive bladder cancer, which is critical for patient management.Another challenging application of DW-MRI in the urogenital tract is the detection of pelvic lymph node metastases.

View Article: PubMed Central - PubMed

Affiliation: Institute of Diagnostic, Pediatric and Interventional Radiology, University Hospital of Bern, Inselspital, Freiburgstrasse 10, Bern, Switzerland.

ABSTRACT
Diffusion-weighted magnetic resonance imaging (DW-MRI) appears to hold promise as a non-invasive imaging modality in the detection of early microstructural and functional changes of different organs. DW-MRI is an imaging technique with a high sensitivity for the detection of a large variety of diseases in the urogenital tract. In kidneys, DW-MRI has shown promise for the characterization of solid lesions. Also in focal T1 hyperintense lesions DW-MRI was able to differentiate hemorrhagic cysts from tumours according to the lower apparent diffusion coefficient (ADC) values reported for renal cell carcinomas. Promising results were also published for the detection of prostate cancer. DW-MRI applied in addition to conventional T2-weighted imaging has been found to improve tumour detection. On a 3 T magnetic resonance unit ADC values were reported to be lower for tumours compared with the normal-appearing peripheral zone. The combined approach of T2-weighted imaging and DW-MRI also showed promising results for the detection of recurrent tumour in patients after radiation therapy. DW-MRI may improve the performance of conventional T2-weighted and contrast-enhanced MRI in the preoperative work-up of bladder cancer, as it may help in distinguishing superficial from muscle invasive bladder cancer, which is critical for patient management. Another challenging application of DW-MRI in the urogenital tract is the detection of pelvic lymph node metastases. As the ADC is generally reduced in malignant tumours and increased under inflammatory conditions, reduced ADC values were expected in patients with lymph node metastases.

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MRI (at 3 T) of a 69-year-old patient with a prostate carcinoma in the PZ on the right side (arrow). (A) On the axial T2-weighted MR image the tumour is visualized as an area of low signal intensity (arrow). (B) On the DW-MR image at a b value of 1000 s/mm2 the tumour is not clearly visualized because of the T2 shine-through effect in the PZ of the prostate. (C) On the ADC map the tumour is clearly visualized as an area of impeded diffusion, represented by colour shades of dark grey, in contrast with the normal PZ of the prostate, which returns colour shades of light grey.
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Figure 5: MRI (at 3 T) of a 69-year-old patient with a prostate carcinoma in the PZ on the right side (arrow). (A) On the axial T2-weighted MR image the tumour is visualized as an area of low signal intensity (arrow). (B) On the DW-MR image at a b value of 1000 s/mm2 the tumour is not clearly visualized because of the T2 shine-through effect in the PZ of the prostate. (C) On the ADC map the tumour is clearly visualized as an area of impeded diffusion, represented by colour shades of dark grey, in contrast with the normal PZ of the prostate, which returns colour shades of light grey.

Mentions: Several studies have demonstrated significantly lower ADC values in prostate carcinoma compared with benign prostatic tissue[50–53], suggesting clinical utility in prostate cancer detection. In particular, the addition of DW-MRI to T2-weighted MRI has been shown to improve the detection of prostatic carcinoma in the PZ[54], as a result of the contrast between the low ADC values of the prostate carcinoma and the relatively high ADC values of the PZ, in which tumours occur in 70% of cases[55] (Fig. 5).Figure 5


DW-MRI of the urogenital tract: applications in oncology.

Petralia G, Thoeny HC - Cancer Imaging (2010)

MRI (at 3 T) of a 69-year-old patient with a prostate carcinoma in the PZ on the right side (arrow). (A) On the axial T2-weighted MR image the tumour is visualized as an area of low signal intensity (arrow). (B) On the DW-MR image at a b value of 1000 s/mm2 the tumour is not clearly visualized because of the T2 shine-through effect in the PZ of the prostate. (C) On the ADC map the tumour is clearly visualized as an area of impeded diffusion, represented by colour shades of dark grey, in contrast with the normal PZ of the prostate, which returns colour shades of light grey.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2967148&req=5

Figure 5: MRI (at 3 T) of a 69-year-old patient with a prostate carcinoma in the PZ on the right side (arrow). (A) On the axial T2-weighted MR image the tumour is visualized as an area of low signal intensity (arrow). (B) On the DW-MR image at a b value of 1000 s/mm2 the tumour is not clearly visualized because of the T2 shine-through effect in the PZ of the prostate. (C) On the ADC map the tumour is clearly visualized as an area of impeded diffusion, represented by colour shades of dark grey, in contrast with the normal PZ of the prostate, which returns colour shades of light grey.
Mentions: Several studies have demonstrated significantly lower ADC values in prostate carcinoma compared with benign prostatic tissue[50–53], suggesting clinical utility in prostate cancer detection. In particular, the addition of DW-MRI to T2-weighted MRI has been shown to improve the detection of prostatic carcinoma in the PZ[54], as a result of the contrast between the low ADC values of the prostate carcinoma and the relatively high ADC values of the PZ, in which tumours occur in 70% of cases[55] (Fig. 5).Figure 5

Bottom Line: Promising results were also published for the detection of prostate cancer.DW-MRI may improve the performance of conventional T2-weighted and contrast-enhanced MRI in the preoperative work-up of bladder cancer, as it may help in distinguishing superficial from muscle invasive bladder cancer, which is critical for patient management.Another challenging application of DW-MRI in the urogenital tract is the detection of pelvic lymph node metastases.

View Article: PubMed Central - PubMed

Affiliation: Institute of Diagnostic, Pediatric and Interventional Radiology, University Hospital of Bern, Inselspital, Freiburgstrasse 10, Bern, Switzerland.

ABSTRACT
Diffusion-weighted magnetic resonance imaging (DW-MRI) appears to hold promise as a non-invasive imaging modality in the detection of early microstructural and functional changes of different organs. DW-MRI is an imaging technique with a high sensitivity for the detection of a large variety of diseases in the urogenital tract. In kidneys, DW-MRI has shown promise for the characterization of solid lesions. Also in focal T1 hyperintense lesions DW-MRI was able to differentiate hemorrhagic cysts from tumours according to the lower apparent diffusion coefficient (ADC) values reported for renal cell carcinomas. Promising results were also published for the detection of prostate cancer. DW-MRI applied in addition to conventional T2-weighted imaging has been found to improve tumour detection. On a 3 T magnetic resonance unit ADC values were reported to be lower for tumours compared with the normal-appearing peripheral zone. The combined approach of T2-weighted imaging and DW-MRI also showed promising results for the detection of recurrent tumour in patients after radiation therapy. DW-MRI may improve the performance of conventional T2-weighted and contrast-enhanced MRI in the preoperative work-up of bladder cancer, as it may help in distinguishing superficial from muscle invasive bladder cancer, which is critical for patient management. Another challenging application of DW-MRI in the urogenital tract is the detection of pelvic lymph node metastases. As the ADC is generally reduced in malignant tumours and increased under inflammatory conditions, reduced ADC values were expected in patients with lymph node metastases.

Show MeSH
Related in: MedlinePlus