Endoclips as novel fiducial markers in trimodality bladder-preserving therapy of muscle-invasive bladder carcinoma: feasibility and patient outcomes.

HYPOTHESIS

Endoclip can be used as fiducial marker in urology.

OBJECTIVE

To assess the feasibility, cost effectiveness and reliability of endoclips as novel fiducial markers in precision radiotherapy, as part of a trimodality bladder-preserving treatment (TBPT) of muscle-invasive bladder carcinoma.

MATERIALS AND METHODS

This retrospective study was performed at Weifang People's Hospital (Weifang, China) from January 2015 to June 2018. A total of 15 patients underwent TBPT. Endoclips were applied to healthy edges of the resected bladder wall as novel fiducial markers. Radio-sensitizing chemotherapy and routine precision radiotherapy were given. The number and position of the endoclips during radiotherapy sessions were monitored. Complications and tumor recurrence were analyzed.

RESULTS

The mean age (±standard deviation) of the patients was 67±10 years (range 46-79). There were 3 females and 12 males. Forty-nine endoclips were applied in all patients (3.3±0.8). The tumor was completely visibly resected in all patients. The number of endoclips remained the same through the planned last radiotherapy session (3.3±0.8), i.e., none were lost. All endoclips were removed after the last radiotherapy session. The average number of follow-up months was 38.9±13.2 (range 11-52). There were no procedure-related complications at discharge or follow-up. At one-year, overall recurrence-free survival was 93.3%. Two patients had recurrences at 18 months and 10 months after TBPT, respectively, and salvage radical cystectomy was performed with no further recurrences. Another patient died due to metastasis 9 months after the completion of therapy.

CONCLUSIONS

Endoclips are reliable, safe and cost-effective as novel fiducial markers in precision-radiotherapy post-TBPT.