Limitations
The retrospective study design was one of our limitations. However,
according to our clinical policy, we performed strict follow-up protocol
for BC patients. The strict follow-up protocol of the patients might
reduce the potential bias associated with the retrospective nature of
the study. The relatively low number of patients was another limitation
of our study. This might be related with the exclusion criteria of our
study population. In order to standardize our study population, patients
with incomplete index TUR-B and patients with no muscle tissue at index
TUR-B specimen were excluded from the study. Another limitation of our
study was the absence of a control group to whom we did not perform
re-TUR. However the presence of a control group in high_risk group is
an ethical problem for this study design. In our clinical practice, we
routinely perform re-TUR to the high_risk NMIBC patients.