Guidelines for the management of NMIBC address the disease’s biological inclination for recurrence or progression [4, 11]. Therefore, we sought to determine the optimal NMIBC surveillance method post BCG induction: whether to perform bladder biopsies in the operating room or to resort to office-based flexible cystoscopy. While bladder biopsy surveillance has an added cost on the healthcare system, results in discomfort to the patient, and augments procedural risks; surveillance flexible cystoscopy begets no objective patho-oncological feedback.
There are multiple risk factors, whether tumor-specific or patient-specific, that can predict NMIBC recurrence. In our cohort, patients who experienced a recurrence had a higher BMI. A higher BMI is associated with hormonal changes and systemic inflammatory response increasing the risk of recurrence and progression of NMIBC [12]. Although the current smoking status was shown to be associated with recurrence, this was not the case in our study [13].
Initial tumor size, tumor multifocality, tumor grade, history of recurrence, a shorter timing of intravesical therapy, and presence of CIS are all disease specific variables associated with recurrence [14,15,16]. Similarly, in our cohort, tumor size, tumor multifocality, and the presence of concomitant CIS were associated with higher odds of recurrence and time to recurrence for NMIBC recurrence. Tumor size and tumor mutlifocality make it harder for complete surgical resection [14]. Furthermore, multifocality implies a biological predisposition where the entire transitional epithelium is subject to genetic instability [14].
Although bladder biopsies have been found to increase the yield and tumor upstaging at the time of initial TURBT, the literature is divided regarding its role in the surveillance stage [17, 18]. While May et al. found that bladder biopsies had a positive impact on therapeutic decisions of all NMIBC patients, Highshaw et al. found that bladder biopsies are unnecessary in case of negative findings on cystoscopy [17, 19]. Similarly, biopsies were found to be unwarranted when cytology and flexible cystoscopy are combined for surveillance [20, 21]. To the authors’ knowledge, this study is the first to assess the time to recurrence when comparing bladder biopsies to flexible cystoscopy. In our cohort, bladder biopsies were as effective as office-based cystoscopy as a surveillance method in terms of recurrence detection or even earlier NMIBC uncovering. Despite the fact that both bladder biopsies and flexible cystoscopy were equally safe and not associated with any grade II or higher Clavien complications, surveillance with bladder biopsies subjects patients to unnecessary anesthesia and added cost [22].
New technologies such as narrow band imaging and blue light cystoscopy increase the yield of detection [23, 24]. However, most developing countries lack these new technologies due to cost issues as well as due to the marginal improvement these tools bring about in overall outcome from a public health standpoint. Moreover, urinary biomarkers have been on the rise recently in the surveillance of NMIBC, but these are currently under investigation and are not for use in clinical practice [24].
4.1 Limitations
Although the data was retrospectively collected, the cohort encompassed non-selected consecutive patients presenting at our tertiary care center. Despite the relatively small sample size, our site is a referral center of neighboring countries ensuring the diversity of our population. The surveillance was performed by different urologists at our institution with each their preference of the method. Additionally, there was no standardized mapping of the bladder biopsies performed and the number of biopsies taken was not recorded in both methods. Furthermore, cystoscopy findings were extracted from operative reports and not from videotaped procedures. Also, in cases of flexible cystoscopy surveillance ascertainment of recurrence has to be with a pathologic specimen.