A new staging criterion for bladder carcinoma using gadolinium‐enhanced magnetic resonance imaging with an endorectal surface coil: a comparison with ultrasonography

Abstract

Objective To evaluate the accuracy of a new staging criterion, submucosal linear enhancement (SLE) on gadolinium-diethylenetriamine-pentaacetic acidenhanced T1-weighted magnetic resonance imaging (MRI) using an endorectal surface coil (endorectal enhanced MRI), and to compare the accuracy of this method with that of transurethral ultrasonography (TUUS). Patients and methods The study included 71 patients with bladder tumours (63 men and eight women, mean age 65.5 years, range 31±85). The SLE coincided with abundant submucosal vascular beds, as reported in a previous study. When the SLE beneath the tumour maintained continuity, the tumour was diagnosed as super®cial (fT1), but if the SLE was interrupted by the tumour, the disease was considered invasive (oT2a). Super®cial muscle invasion (less than half the muscle layer) and deep muscle invasion (more than half the muscle layer) were classi®ed as T2a and T2b, respectively. When the tumour formed an extravesical mass, the tumour was classi®ed as T3b. Results The staging accuracy for bladder tumours using SLE on endorectal-enhanced MRI or TUUS was 83% and 60%, respectively (P<0.01). Using the SLE, muscle invasion of bladder tumour was diagnosed with an accuracy of 87%, a sensitivity of 91% and a speci®city of 87%; this was signi®cantly better than with TUUS (P<0.01). Conclusion The criterion of SLE on Gd-DTPA enhanced T1-weighted MRI using an endorectal surface coil is useful for staging bladder tumour, and the staging accuracy is signi®cantly better than with TUUS.

Currently used non-specific extracellular MR contrast media

“…It has been reported in numerous publications that Gd chelates improve sensitivity, specificity and diagnostic accuracy of MR procedures [5,21,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60]. Indications for their use include the evaluation of tumoral, traumatic and infectious disease processes.…”

“…The combined use of Gd chelates and breathhold imaging (increased tumour-to-parenchyma contrast ratio) results in better tumour detection in most organs, as compared with unenhanced MR imaging. Most MR information for characterizing liver [44,45] and renal [53,54] tumours, and in the pretherapeutic assessment of uterine [55], ovarian [56], bladder and prostate tumours [57,58]. Controversies remain concerning the best contrast agent for MR imaging of the liver, either for detection or characterization: extracellular compounds; superparamagnetic particles; manganese or gadobenate dimeglumine which has a nonspecific extracellular phase followed by specific uptake by functioning hepatocytes prior to its excretion into the bile.…”

A New Parameter for Staging Bladder Carcinoma

“…19 Recently, it has been reported that cross-sectional imaging is only useful after the tumor escapes beyond the bladder wall. 20 Thereby, it was reported in a recent study by Hayashi et al 14 that CT cannot distinguish between tumors with stages lower than T2b.…”

“…20 Furthermore, conventional MRI was reported in the aforementioned study by Hayashi et al 14 to be ineffective for differentiation of both stage Ta from stage T1 and stage T2a from stage T2b. In the same study, the authors reported accuracy of 66% and sensitivity of 78% for muscle invasion using TUUS.…”

“…Transurethral ultrasonography (TUUS) has also been reported to be a diagnostic option in bladder cancer staging despite having technical limitations such as acoustic shadows produced by tumor interface calcification and absorption of ultrasound by large tumors. 14 As a newer ultrasonographic technique, high-frequency endoluminal ultrasonography has been reported to be equally useful for staging diagnosis of bladder cancer, with reported accuracy of 84% for each. 15 However, the technique has the inherent limitations of an inability to evaluate the depth of invasion of large tumors having a broad base because of the lack of penetration of the ultrasound beam and an inability to visualize the tumor base located in the bladder neck.…”