Comparison of dynamic contrast-enhanced and diffusion weighted magnetic resonance image in staging and grading of carcinoma bladder with histopathological correlation

Abstract

Background: Bladder cancer is the second most common neoplasm of the urinary tract worldwide. Dynamic contrast-enhanced and diffusion-weighted MRI has been introduced in clinical MRI protocols of bladder cancer because of its accuracy in staging and grading.

Aim: To evaluate and compare accuracy of Dynamic contrast enhanced (DCE) and Diffusion weighted (DW) MRI for preoperative T staging of urinary bladder cancer and find correlation between apparent diffusion coefficient (ADC) and maximum enhancement with histological grade.

Materials and methods: Sixty patients with bladder cancer were included in study. All patients underwent Magnetic Resonance Imaging (MRI) on a 1.5-T scanner with a phased-array pelvic coil. MR images were evaluated and assigned a stage which was compared with the histolopathological staging. ADC value and maximum enhancement curve were used based on previous studies. Subsequently histological grade was compared with MR characteristics.

Results: The extent of agreement between the radiologic staging and histopathological staging was relatively greater with the DW-MRI (κ=0.669) than DCE-MRI (κ=0.619). The sensitivity, specificity, and accuracy are maximum and similar for stage T4 tumors in both DCEMRI (100.0, 96.2 and 96.7) and DW-MRI (100.0, 96.2 and 96.7) while minimum for stage T2 tumors - DCEMRI (83.3, 72.2, and 76.7) and DWI-MRI (91.7, 72.2, and 80).

Conclusion: MRI is an effective tool for determining T stage and histological grade of urinary bladder cancers. Stage T2a and T2b can be differentiated only by DCE-MRI. Results were more accurate when both ADC and DCE-MRI were used together and hence a combined approach is suggested.

Keywords: Digits; hand; upper limb; varicose veins; varicosities.

Figure 1

Stage 1 Grade 2 transitional cell carcinoma (a and b) T1- and T2-weighted image shows a single polypoidal intraluminal anterior wall mass (c) diffusion-weighted images a single polypoidal intraluminal anterior wall mass with diffusion restriction (d) dynamic contrast-enhanced imaging shows a single polypoidal intraluminal anterior wall mass showing intense enhancement

Figure 2

Stage 2 Grade 1 transitional cell carcinoma (a and b) T1- and T2-weighted image showing single intraluminal mass near left VesicoUreteric Junction (L-VUJ) (c) diffusion-weighted images shoes restricted diffusion (d) dynamic contrast-enhanced image showing rapidly enhancing single intraluminal mass near L-VUJ followed by slow increase

Figure 3

Stage T3b and Grade 3 carcinosarcoma (a) T1-W image showing left posterolateral wall mass abutting left VesicoUreteric Junction (L-VUJ) (b) T2-W image showing left posterolateral wall mass abutting L-VUJ with Foley's in situ (c) diffusion weighted image showing diffusion restriction with perivesical extension (d) dynamic contrast-enhanced image shows enhancing L-posterolateral mass abutting L-VUJ and perivesical extension

Figure 4

Stage T4a and Grade 3 transitional cell carcinoma (a and b) T1 and T2 images showing right-VesicoUreteric Junction (R-VUJ) mass with extravesical spread and seminal vesicle involvement (c) diffusion weighted images shows restricted diffusion (d) dynamic contrast-enhanced image shows rapid enhancing R-VUJ mass and involvement of prostate and seminal vesicle

Figure 5

Time intensity curve and mean ADC values (a) Grade 1 lesion showing rapid early enhancement followed by slow increase with mean ADC value 1700 (b) Grade 2 lesion showing plateau curve with mean ADC value 1200 (c) Grade 3 lesion showing rapid enhancement followed by rapid wash out and mean ADC value 823.54