Bladder cancer (BCa) is a highly prevalent disease worldwide and one with the highest managment costs. Surgical management of non muscle and muscle invasive bladder cancer (NMIBC, MIBC) differs substantially. The initial transurethral resection of bladder tumor (TURBT) is the first diagnostic and therapeutic procedure for NMIBC, instead, only a diagnostic procedure for MIBC patients suitable for radical cystectomy (RC). For this reason, prognosis and treatment of patients with BCa requires accurate staging at the time of diagnosis.
Recently, a reporting system standardizing multiparametric magnetic resonance imaging (mpMRI) of the bladder, the Vesical Imaging-Reporting and Data system (VI-RADS), has been developed with the aim to differentiate NMIBC from MIBC.
The category of high-risk NMIBC (HR-NMIBCs) undergo repeated transurethral resection of bladder tumor site (Re-TURBT) due to risk of persistent and/or understaged disease after initial TURBT.
In light of the background, the aim of the project are to prospectively asses the use of VI-RADS in NMI-and-MIBC discrimination at TURBT, to identify HR-NMIBCs who could potentially avoid Re-TURBT and to detect those at higher risk for understaging after TURBT.
Patients referred for bladder cancer (BCa) suspicion, at our institution will be offered multiparametric magnetic-resonance-imaging (mpMRI) of the bladder before TURBT. According to VI-RADS, a cutoff >= 3 to define MIBC will be assumed. Primary TURBT reports (whole cohort) will be compared with preoperative VI-RADS scores to assess accuracy of mpMRI in discriminating NMI-and-MIBC.
At the same time, re-TURBT reports from HR-NMIBCs will be compared with preoperatively recorded VI-RADS scores to assess accuracy of mpMRI in predicting Re-TURBT outcomes.
According to the EAU guidelines, diagnosis and local staging of BCa rely on cystoscopy and histological evaluation of bladder tissue. Imaging techniques such as computed tomography and MRI are mainly reserved for lymph node and distant disease staging, with the important caveat that neither technique can be used to assess the primary tumor stage. It is well known that guidelines lag behind the best current clinical practice.
TURBT is the first diagnostic, prognostic, and therapeutic procedure still mandatory to provide crucial information such as tumor grading, histologic variant of bladder neoplasms, and, of course, tumor stage. Other important goals of TURBT are represented by definition of the depth of tumor invasion, and by removal of all visible non-invasive lesions [6,17,18]. Nevertheless, a number of quality issues, some potentially linked to the experience of the surgeon, suggest that the initial TUR may be inadequate in a high percent of HR-NMIBC patients [8,19]. In this setting, principal concerns are mainly represented by the possibility of persistent and/or understaged disease after initial TURBT especially for the highest-risk category of T1-HG tumors. More importantly, underestimation of tumor depth invasion at first TURB represents an even more strikingly event responsible for adverse survival outcomes. Thus, integration of imaging in the local staging of BC is to be welcomed if it can improve overall accuracy. Despite the undeniable advances in mpMRI of the bladder, there is lack of standardization in terms of protocol and reporting.
The aim of the present research is to identify within HR-NMIBCs those who could potentially avoid unnecessary Re-TURBT and on the other hand, to detect those who are at risk for understaged disease after primary resection who should not miss Re-TURBT.
Expected results and clinical practice implications:
Clinical Implication from Aim I:
- within HR-NMIBC, to predict pathologic report at Re-TURBT in order to improve selection of patients who could avoid secondary invasive transurethral resection (VI-RADS 1-2) from those who absolutely should not miss it (VI-RADS 3-5).
- to reduce intra- and postoperative complications related to a potentially unnecessary invasive surgical endoscopic procedure (i.e. Re-TURBT for VI-RADS 1-2 cases)
- to impact on socio-economics health care related costs (i.e. eliminating a procedure form the algorithm management of BCa patients)
Clinical Implication from Aim II:
- to help in discriminating BCa patients who may benefit from an extensive TURBT (VI-RADS 1-2) as per curative intent from those who will need a sampling procedure with the only aim to start a multidisciplinary protocol involving oncologist for neoadjuvant regimens and subsequently urologist for RC (VI-RADS 3-5).
- to avoid unnecessary long-lasting procedures (i.e. extensive first TURBT) in BCa patients suitable for radical treatment.