AUA 2018: Can Imaging Response Following Neoadjuvant Chemotherapy in Upper Tract Urothelial Cancer Be a Surrogate For Pathologic Response?

San Francisco, CA (UroToday.com) Pathological response following neoadjuvant chemotherapy (NAC) has been shown to be an excellent surrogate for survival in bladder cancer. However, in upper tract urothelial cancer (UTUC), unlike bladder, preoperative endoscopic and pathologic assessment of response is difficult. The authors presented a study aiming to determine whether imaging response following NAC predicted the final pathologic stage and outcomes following radical nephroureterectomy (RNU).

All RNUSs performed at the authors’ institution from January 1995 until July 2017 were identified. All cytology and biopsy-proven, cT2anyNM0 high grade UTUC patients who underwent NAC with cisplatin based chemotherapy prior to RNU were analyzed. Evaluation with CT/MR urography was available both before and after NAC for all included patients. Radiological response rate (RRR) was estimated using the RECIST criteria and pathologic response was defined as final pathology less than pT2. The association between RRR and overall survival, after adjusting for a risk score comprised of tumor location, hydronephrosis, and local invasion was analyzed.

The authors demonstrated that of the 685 RNUs performed during the study period, 62 (9.1%; 95% CI 7.1%-12%) underwent cisplatin based NAC preoperatively.  Patients who underwent NAC were younger at the time of RNU (median of 66 years vs. 71 years, p=0.0001) and had their RNU in more recent years (median surgery year of 2013 vs 2007, p<0.0001), than patients who did not undergo cisplatin-based NAC. When looking at the response rates on imaging, it was demonstrated that 16% had complete response; 52% partial response; 27% stable disease; and 5% had progression. A total of thirty-six patients (58%; 95% CI 45%-70%) responded to cisplatin-based chemotherapy on pathology.

The authors demonstrated that radiological response was significantly associated with lower tumor stage on pathology (74% among complete or partial response vs 25% among stable disease or progression, p=0.0004). On multivariable analysis, radiological response was associated with better overall survival (HR 0.48) although it was not statistically significant (95% CI 0.17-1.31; p=0.2). This is most probably due to a low event rate (16 deaths).

In summary, radiological response rates following NAC in UTUC is significantly associated with pathologic response but no significant correlation could be found with better overall survival following RNU. Urologists should consider using this as a useful preoperative tool to counsel and optimize management of UTUC patients.

Presented by: Nirmal Thampi John, MD, New York, US
Co-Authors: Amy Tin, Daniel Sjoberg, Nicole Benfante, A Ari Hakimi, Paul Russo, Jonathan Coleman, New York, NY

Written by:  Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre @GoldbergHanan at the 2018 AUA Annual Meeting - May 18 - 21, 2018 – San Francisco, CA USA