At this year's Genitourinary Cancers Symposium, Shilpa Gupta, MD, of the Cleveland Clinic Taussig Cancer Institute in Ohio, discussed some current controversies in treating muscle-invasive bladder cancer (MIBC) and offered a pragmatic approach for bringing new treatments to the forefront. In this exclusive 51˶ video, Gupta reviews some of the highlights of her innovation session.
Following is a transcript of her remarks:
In this innovation session, I always think, "Why can we not do an -like study, like breast cancer patients have had the opportunity for the past decade?" Where you have a new drug, you quickly test its efficacy in the neoadjuvant setting -- if it is showing efficacy, you graduate it to the next level.
Now currently for bladder cancer, how things work is we have a new drug which shows efficacy in metastatic disease, and then we try to move it earlier and earlier in the muscle-invasive bladder cancer, neoadjuvant setting. If we had an I-SPY-like design, we would first test it in the muscle-invasive bladder cancer, where there'll be a quick readout with the cystectomy. We'll know if a drug is effective, and then we can graduate it to other settings. This is really a pragmatic approach, and we need to do something like this in bladder cancer.
There are a lot of areas of controversy [in MIBC]. To name a few: Is pathologic complete response [pCR] the ideal endpoint in the immunotherapy era? We know that many times immunotherapy may not really lead to very high pathologic response rates or downstaging to pCR, but it might affect the durability or the event-free survival. And pCR has not been validated as an individual-level or a trial-level surrogate in MIBC so far.
And also we need to answer the question whether disease-free survival without overall survival improvement is enough for adjuvant therapy. Can we spare patients unnecessary treatment, physical and financial toxicities if similar survival can be obtained when treated at time of relapse?
For patients with upper-tract urothelial cancer who are cisplatin-ineligible, we don't know if gem/carbo [gemcitabine plus carboplatin] is better than nivolumab [Opdivo] or they're similar, because such a trial has not been done. So it's really important to talk to patients about both the options and discuss the trial data.
And lastly, most of the trials that are ongoing only include patients with predominant urothelial cancer histology to avoid heterogeneity. But the fact of the matter is that bladder cancer patients have heterogeneous disease. And when we don't include patients with variant histology, predominant variant histology, we really don't know what the signal would be in those kind of patients' tumors. But when the drugs get approved, we do extrapolate that data. So it would be really good to include patients, and get that signal, because doing pure variant histology trials can become less practical.