Washington, DC (UroToday.com) Organ preservation in bladder cancer has been a widely debated topic with polarizing views from different centers and researchers worldwide. At the SUO 2019 meeting in Washington, DC, during the session on organ preservation in urologic cancers, Professor Robert Huddart from the Royal Marsden presented on Muscle-invasive bladder cancer (MIBC).
Prof. Huddart started his talk by emphasizing the advantages of trimodal therapy (TMT) for bladder cancer preservation. He presented the examples of organ preservation in the breast, laryngeal, anal and prostate cancer, as the current standard. He then highlighted the BC 2001 long-term follow-up data presented at GU ASCO 2017, which showed that with extended follow-up, there is improved locoregional control and a reduced salvage cystectomy rate with TMT. After adjustment for known prognostic factors, this study showed an improvement in bladder-cancer specific survival.
He then presented the findings from the SPARE trial, which tested the feasibility of a randomized trial in MIBC and compared outcomes in patients who received neoadjuvant chemotherapy followed by radical cystectomy (RC) or bladder preservation. Trial recruitment was challenging and below the predefined target, with 45 patients recruited in 30 months. Non‐compliance with assigned treatment strategy was frequent; six of the 25 patients (24%) randomized to RC received radiation therapy (RT). The long-term bladder preservation rate was 11/15 (73%) in those who received RT per protocol. OS was not significantly different between the two groups. There are multiple population-based studies comparing RT and surgery, which have reported conflicting results because the comparison is not between identical populations. He then highlighted some of the challenges of RT to the bladder, which includes a deformable and mobile configuration of the bladder based on the urine volume and stool content in the rectum. These can be counteracted with adaptive radiotherapy by building the individualized library of plans.
He also presented a comparison of early mortality rates between RT and surgery from a 2003 study, which was in favor of RT. This difference in mortality rates persisted even after the centralization of care in the United Kingdom. He went on to highlight the concern with late toxicity. When comparing overall incidence of late toxicity, it was less than predicted, with a cumulative 2-year Radiation Therapy Oncology Group grade 3/4 toxicity rate of 13% and no statistically significant differences between standard whole-bladder radiation therapy and reduced high-dose volume radiation therapy that aimed to deliver full radiation dose to the tumor and 80% of maximum dose to the uninvolved bladder. The data from the SPARE trial also showed that more patients undergoing RC had CTCAE grade 3–4 toxicity.
He then compared anal and bladder cancer and mentioned that overall survival is around 50% with TMT for bladder cancer comparable to 58% for anal cancer, where the standard of care is organ preservation now. He stressed on a paradigm shift, where he mentioned that bladder cancer should be treated as new anal cancer.
Professor Huddart concluded his talk by summarizing that TMT is a rational approach for most patients with MIBC with a lower risk of immediate mortality and modest toxicity. Though it is not for everyone, it should be offered to all suitable patients.
Presented by: Robert Huddart, MA, MBBS, MRCP, FRCR, The Royal Marsden, United Kingdom
Written by: Abhishek Srivastava, MD, Society of Urologic Oncology Fellow, Fox Chase Cancer Center, Fox Chase Cancer Center, Philadelphia, PA, @shekabhishek, at the 20th Annual Meeting of the Society of Urologic Oncology (SUO), December 4 - 6, 2019, Washington, DC