Until recently, there have been very limited randomized data to guide the provision of perioperative systemic therapy in upper tract urothelial carcinoma. Thus, data has been extrapolated from patients with urothelial carcinoma of the bladder.
Neoadjuvant therapy
Data for the use of neoadjuvant chemotherapy prior to radical cystectomy in urothelial carcinoma of the bladder are robust: the Advanced Bladder Cancer meta-analysis collaboration, in a meta-analysis of 11 trials with 3,005 patients, demonstrated a significant survival benefit to the use of neoadjuvant platinum-based combination chemotherapy as compared to upfront surgery (hazard ratio 0.86, 95% confidence interval 0.77 to 0.95). In absolute terms, this corresponds to a 5% absolute survival at 5 years.5In contrast, there is extremely limited data regarding the use of neoadjuvant chemotherapy in patients with upper tract urothelial carcinoma. No institution has published data on more than 50 patients who received neoadjuvant chemotherapy prior to nephroureterectomy. In two publications, the MD Anderson Cancer Center group has reported on their experience. Matin et al. reported on 43 patients with biopsy-proven high-grade upper tract urothelial carcinoma who underwent neoadjuvant chemotherapy prior to nephroureterectomy.6 They demonstrated a 14% pathologic complete response rate in this cohort. Additionally, when compared to historical controls, there was an increased likelihood of downstage (p=0.004): pT2 disease was found in 49% compared with 65% in controls and pT3 disease was found in 28% compared with 48%. In a more recent analysis, Porten et al. provided a retrospective review of 31 patients who underwent neoadjuvant chemotherapy prior to nephroureterectomy compared to 81 historical controls who received initial surgery for high-risk upper tract urothelial carcinoma.7 They demonstrated that patients receiving neoadjuvant chemotherapy had improved five year overall survival (80% versus 58%, p=0.02) and five year disease-specific survival (90% versus 58%, p=0.002). After adjusting for relevant patient, treatment and tumor characteristics, the risk of overall mortality (hazard ratio 0.42, p=0.035) and disease-specific mortality (hazard ratio 0.19, p=0.006) were significantly lower among patients who received neoadjuvant therapy.
More recently, Kubota and colleagues reported a multi-institutional analysis of 101 patients with high-risk upper tract urothelial carcinoma (stage cT3-4 or cN+) who received neoadjuvant chemotherapy prior to nephroureterectomy at 5 medical centers in Japan and compared these to 133 patients who received surgery alone.8 Most patients who received neoadjuvant chemotherapy in this cohort were given gemcitabine and carboplatin (75%) while a minority received gemcitabine and cisplatin (21%). The authors found that while neoadjuvant chemotherapy increased pathological downstaging and was independently predictive of improved recurrence-free survival and cancer-specific survival, they were unable to demonstrate improvements in overall survival.
Finally, in 2018, Liao et al reported their experience from Johns Hopkins.9 They compared 32 patients who received neoadjuvant chemotherapy prior to nephroureterectomy for biopsy-proven high-grade upper tract urothelial carcinoma to 208 patients who underwent surgery alone. These authors found a 9.4% pathologic complete response rate in addition to significant pathologic downstaging.
In comparison to the use of neoadjuvant chemotherapy for urothelial carcinoma of the bladder, there is potentially even greater rationale for its use in upper tract urothelial carcinoma. First, patients are much more likely to be able to tolerate a highly efficacious regime (gemcitabine and cisplatin) with two functioning kidneys prior to nephroureterectomy than they will post-operatively. Additionally, important prognostic information can be derived if patients experience pathological downstaging.1 However, one of the primary barriers to the use of neoadjuvant chemotherapy is the lack of reliable pre-operative pathologic specimens to identify invasive disease, as mentioned previously. Second, there are concerns regarding the delay to definitive surgical treatment, particularly in patients who may have chemoresistant disease. Third, there are concerns regarding a potential increase in perioperative morbidity.
Finally, there is a concern of overtreatment through the use of toxic medications in patients who may or may not have invasive disease. There have been attempts to assess the role of neoadjuvant chemotherapy in this patient population. A trial from the University of Michigan was terminated due to poor accrual (NCT01663285). Memorial Sloan Kettering is a sponsor for a trial of gemcitabine and cisplatin as neoadjuvant chemotherapy in patients with upper tract urothelial carcinoma, which according to the last update remains active but is no longer recruiting. This trial sought to enroll 57 participants in a Phase II design to assess the primary outcome of pathological response rate. Additionally, a Phase II ECOG-ACRIN trial seeking to assess pathologic complete response rates following neoadjuvant chemotherapy (MVAC or gemcitabine and cisplatin) among 36 patients with high-grade upper tract urothelial carcinoma. Results have not yet been published though they were presented at AUA 2018. While the gemcitabine and cisplatin arm did not meet accrual, 30 patients were accrued to the ddMVAC arm. Pathologic complete response was seen in 6 of 29 evaluable patients. None of these trials have provided a randomized comparison to surgery alone. In contrast, NCT02876861 is a trial from Xiangya Hospital of Central South University which is actively recruiting patients and randomizing to neoadjuvant chemotherapy with gemcitabine and cisplatin prior to nephroureterectomy or surgery alone. They are targeting accrual of 50 patients to assess the primary outcome of disease-free survival.
Adjuvant chemotherapy
Again, there is strong evidence for adjuvant chemotherapy in urothelial carcinoma of the bladder. In contrast to neoadjuvant chemotherapy, the data for adjuvant chemotherapy in upper tract urothelial carcinoma are more robust.First, there is a meta-analysis of nine retrospective cohort studies comparing 482 patients who received adjuvant chemotherapy to 1,300 patients who were treated with surgery alone. Those who received adjuvant therapy had significantly improved disease-free survival (hazard ratio 0.49, 95% confidence interval 0.24 to 0.99) and overall survival (hazard ratio 0.43, 95% confidence interval 0.21 to 0.89)10. This analysis is limited by significant selection biases.
In contrast, a Phase III randomized trial of perioperative chemotherapy versus surveillance in upper tract urothelial cancer (POUT) is a Phase III, multicenter trial from the Institute of Cancer Research in the United Kingdom which randomized patients who are chemotherapy eligible with pT2-4, pN0-3 or pT1, pN+ following nephroureterectomy to adjuvant platinum-based chemotherapy or surveillance. The results of this trial remain to be published, although they have been presented at ASCO GU and EAU in 2018. To summarize, 123 patients were randomized to surveillance and 125 to adjuvant chemotherapy at 57 different centers. Patients in the intervention arm received either gemcitabine and cisplatin or gemcitabine and carboplatin as their renal function allowed. The majority of enrolled patients had pT3 disease (65%) and were node-negative (pN0, 91%). The authors demonstrated that adjuvant chemotherapy significantly improved disease-free survival (hazard ratio 0.49, 95% confidence interval 0.31 to 0.76) as well as metastasis-free survival (hazard ratio 0.49, 95% confidence interval 0.30 to 0.79). However, overall survival data were not yet mature at the time of presentation, so despite the separation of the curves, a meaningful benefit cannot be shown yet. Grade 3 or greater toxicity was experienced by 60% of patients receiving adjuvant chemotherapy and 24% of patients undergoing surveillance.
Previous analyses have demonstrated that patients are much less likely to derive benefit from non-cisplatin based regimes10. Thus, a significant decline in renal function attributable to nephroureterectomy may result in many patients being unable to receive optimal systemic therapy.
Immunotherapy
The data discussed this far center on the use of cytotoxic chemotherapy, whether gemcitabine and cisplatin, MVAC, or gemcitabine and carboplatin, as these have been the traditional agents used for patients with urothelial carcinoma. Following data supporting the role of immunotherapy using checkpoint inhibitors in patients with advanced metastatic urothelial carcinoma, the recently published Phase II PURE-01 trial examined neoadjuvant pembrolizumab for muscle-invasive urothelial bladder carcinoma11. This analysis demonstrated higher rates of pathologic complete response (42%) and downstaging to non-muscle invasive disease (54%) than would be expected from historical use of cytotoxic chemotherapy, though a randomized control was not employed in this analysis. Analyses of durvalumab plus tremelimumab and of gemcitabine plus cisplatin plus pembrolizumab demonstrated similarly promising results. This approach has not, to our knowledge, been tested in upper tract urothelial carcinoma but such an approach may be particularly valuable in these patients.Conclusions
At the 2018 Society of Urologic Oncology meeting, Dr. Jean Hoffman-Censits presented on the role of neoadjuvant chemotherapy in these patients. She discussed differences between urothelial carcinomas of the bladder and of the upper urinary tract. Notably, she highlighted that pathologic response rates appear to be lower in patients with upper tract urothelial carcinoma (9-15%) as compared to bladder cancer (>20%). The ongoing URANUS trial will better delineate the role of neoadjuvant therapy in upper tract urothelial carcinoma.Published Date: December 2019