br T weighted and dynamic contrast
T2-weighted and dynamic contrast-enhanced magnetic resonance imaging (MRI) recently replaced computed tomography urography (CTU) for the differentiation be-tween NMIBC and MIBC . Although imaging is not the gold standard to evaluate the invasiveness of BC, an MRI-based standardized reporting system, the Vesical Imaging Reporting and Data System (VI-RADS) , has recently been suggested in order to better define the lesions and improve peer-to-peer communication . However, there are several factors that limit the diffusion of MRI for BC staging, such as the overstaging rate, procedure-related contraindications and costs, as well as the use of gadolinium-based contrast agents, which should be avoided in patients with impaired renal function .
Recently, 29-MHz high-resolution microultrasound (mUS) technology has been suggested as a potential noninferior alternative to multiparametric MRI (mpMRI) for the detection of clinically significant prostate cancer (csPCa) [7,8]. The benefit of this technology is extremely high resolution, down to 70 mm, which provides a signifi-cant improvement in the visualization of tissue details compared with standard US. In addition, since it is a US-based imaging technique, mUS provides the same benefits, such as real-time evaluation and cost effectiveness. Based on our previous experience with mUS technology for the detection of prostate cancer (PCa), we tested the hypothesis that high-resolution mUS assessment may effectively depict the anatomical structures of GW311616 wall and, thus, may be capable of discriminating between NMIBC and MIBC.
and M.L.), who were routinely using mUS for the detection of PCa, and who were blinded to the number and location of the lesions, performed the assessment. Images and recording of the bladder were archived for retrospective analysis after TUR and pathological analysis. The bladder was previously emptied by catheterization and afterward filled with 50 cc of sterile saline solution. The mUS was performed transrectally in males and transvaginally in females, and a rectal enema was performed in the male population before the procedure.
The first endpoint was to investigate the feasibility of the procedure defined as the possibility to assess the bladder window. Under this setting, we investigated the differences between male and female populations considering the different anatomy. The second step was to define the features of a normal bladder wall with mUS. The mUS images were qualitatively evaluated and measured to estimate a “normal” picture. We identified the three layers of the bladder wall structure: the mucosa, the detrusor muscle, and the adventitia. We defined a normal bladder wall when all the layers were adequately represented, and no mass or layer interruption was identified. The third step was to recognize, describe, and differentiate the bladder wall lesions between NMIBC and MIBC. The investigators’ description included site, size, and tumor margins. The fourth step was to correlate the mUS findings with the pathological report. All mUS image sets were interpreted while blinded to any histopathological information. An “en bloc” TUR was performed as previously described in patients with four or fewer lesions and tumors of 3 cm excluding those very close to the ostia, in the dome and/or the anterior bladder wall. All other patients received a standard bipolar TUR .
2.1. Pathological assessment
All specimens were fixed in 10% formalin, embedded in paraffin, cut, and stained with hematoxylin and eosin. Specimens were examined by two expert uropathologists (P.C. and M.G.E.) to assess the type, grade, and stage of the tumor. Malignant tumors were classified and graded according to the World Health Organization classification . Tumor staging was defined according to the American Joint Committee on Cancer/Union for International Cancer Control TNM system .
Twenty-three patients, 12 males (52.17%) and 11 females (47.83%), were prospectively enrolled in our study. Patients’ mean age was 65.48 yr (standard deviation: 12.78). Demographics and clinical features of the cases are summarized in Table 1. A case-by-case description is reported in Table 2.
2. Patients and methods
This study included male and female adults referred to our tertiary urological center with the diagnosis of primary BC, diagnosed by either flexible cystoscopy or transabdominal ultrasonography, who were subsequently scheduled for endoscopic treatment. Patients with urethral, anal, and vaginal stricture; hip problems that do not allow the lithotomic position; previous pelvic surgery; and BMI >30 were excluded. The institutional review board and local ethical committee approved the study (Protocol ICH-2004-003 approved in September 2018), and all patients signed an informed consent form.