Objective: The aim of the present study was to analyze the pattern of recurrences after bladder-preserving therapy for muscle-invasive bladder cancer.
Methods: The subjects were 77 patients with T2-3N0M0 bladder cancer whose bladder was preserved by intra-arterial chemotherapy and radiation. The patterns of the first recurrences were retrospectively analyzed.
Results: With a median follow-up of 38.5 months, 17 patients (22.1%) experienced intravesical recurrence without metastasis, 14 (82.4%) of which were cases of non-muscle-invasive bladder cancer recurrence and 3 (17.6%) of which were muscle-invasive bladder cancer recurrences. Muscle-invasive bladder cancer recurred at the same site as the initial tumor site in all three cases, whereas non-muscle-invasive bladder cancer recurred at different sites in 64% of the patients in that group. The peak hazard of the non-muscle-invasive bladder cancer recurrence was observed at around a year after treatment. Recurrent non-muscle-invasive bladder cancer was of a significantly lower histological grade with lower Ki-67-labeling indices than the initial muscle-invasive bladder cancer. Twelve (85.7%) of 14 patients with non-muscle-invasive bladder cancer recurrence achieved disease-free status. The multivariate analysis revealed that multiplicity, grade and tumor size were significantly correlated with the recurrence (P= 0.0001, 0.0442 and 0.0412, respectively).
Conclusions: Most of the recurrences after bladder-preserving therapy were cases of non-muscle-invasive bladder cancer. The recurrence pattern and characteristics of the tumors did not differ from those of primary non-muscle-invasive bladder cancer. Patients with high-risk factors would be candidates for prophylactic intravesical therapy for non-muscle-invasive bladder cancer recurrence.