EAU 2017: Multimodal bladder preservation technique for muscle invasive bladder cancer: Results from a prospective trial

London, England (UroToday.com) Bladder preservation in muscle-invasion bladder cancer (MIBC) has recently been brought back into consideration as an alternative to radical cystectomy, though that remains standard of care. The authors, with prior experience with trimodal therapy (maximal local resection combined with chemoradiation therapy), detail their experience with a novel tetramodal bladder sparing therapy.

Tetramodal bladder preservation therapy, which extends trimodal therapy to include selective intra-arterial infusion of chemotherapeutics, is based on the principle of maximizing chemotherapy to the target organ. The utilized pathway is detailed in Figure 1 below:

chart 2

Specifically, they utilized BOAI (balloon occluded arterial infusion) through a femoral arterial puncture As they describe: “The catheter was introduced into the posterior trunk of the internal iliac artery via contralateral femoral artery access. After the distal balloon had passed through the furcation of the anterior trunk of the internal iliac artery, the distal and proximal balloons were inflated and immobilized to isolate the anterior trunk of the internal iliac artery, which lies upstream of the target vessels For the intra-arterial infusion procedure, we used an intraarterial catheter equipped with two 6-Fr occlusion balloons.” Ideally, they are targeting the vesicle arteries.

In this single-center, proof of principle, prospective single arm study, 410 patients were enrolled for tetramodal therapy. Unfortunately, for the entire cohort, they don’t list PFS outcomes. However, the mean 8-year OS was 75.1 months (95% CI; 70.5-79.7) for cT2 versus 77.1 months (95% CI; 67.7-86.5) for cT3, and 41.8 months (31.7-52.0) for cT4. For cT2/T3 patients, however, Kaplan-Meier curves demonstrate 5-year PFS and OS to be approximately 60% and 80% (though exact numbers not listed). Their primary analyses focused on univariate and multivariable analyses to identify predictors of improved 8-year PFS and OS. Essentially, for the entire cohort, age, T-stage, N-stage and hydronephrosis predicted worse outcomes. However, for a subset analysis of cT2/3 patients alone (320 patients), T-stage alone predicted worse OS, but T-stage, age, hydronephrosis and tumor grade predicted worse PFS. Ultimately, they state that tetramodal therapy improves outcomes from bladder preservation therapy, and note that cT2/3 patients with no hydronephrosis may be ideal candidates.

Limitations / Discussion Points:
1. There is no data or comparison to trimodal therapy or RC alone. As such, it is unclear if tetramodal therapy has any benefit over trimodal therapy, let alone RC.
2. Other single institution studies have reported similar outcomes with just trimodal therapy.
3. While this is a novel technique, and an example of utilizing technology from other cancers and introducing it to the GU Oncology sphere, further prospective studies need to be done to determine if the extra morbidity is validated by survival benefit.

Presented by: T. Inamoto

Co-Authors: Takahara K., Ibuki N., Takai T., Uchimoto T., Saito K., Tanda N., Yoshikawa Y., Minami K., Hirano H., Nomi H., Azuma H., Yamamoto K., Shinbo T., Yamamoto K., Narumi Y.

1. Osaka Medical College, Osaka, Japan
2. Osaka Medical College, Dept. of Urology, Osaka, Japan
3. Osaka Medical College Mishima-Minami Hospital, Dept. of Urology, Osaka, Japan
4. Osaka Medical College, Dept. of Radiology, Osaka, Japan

Written by: Thenappan Chandrasekar, Clinical Fellow, University of Toronto

Twitter: @tchandra_uromd

at the #EAU17 -March 24-28, 2017- London, England