(UTUC) and should therefore be a new standard of care, according to investigators from the POUT trial.
The risk of disease-free survival events was reduced by more than half for patients who started platinum-based chemotherapy within 90 days after nephroureterectomy, compared with counterparts who simply received surveillance. The treatment was generally well tolerated, with adverse events as expected for this regimen and only a transient impact on quality of life.
Alison Birtle, MD, of Lancashire Teaching Hospitals National Health Services Foundation Trust in Preston, England, and colleagues conducted this trial and reported the results in the Lancet.
“Urothelial carcinomas of the upper urinary tract … are rare, with poorer stage-for-stage prognosis than urothelial carcinomas of the urinary bladder,” the investigators wrote. “No international consensus exists on the benefit of adjuvant chemotherapy for patients with UTUCs after nephroureterectomy with curative intent.”
With this in mind, the investigators conducted the phase 3 POUT trial (NCT01993979), which is the largest trial to report outcomes exclusively in patients with UTUC. The trial included 261 patients with UTUC (transitional cell carcinoma of the ureter or renal pelvis) that was locally advanced at either pT2-T4 pN0-N3 M0 stage or pTany N1-3 M0 stage.
Patients were randomized to chemotherapy (n = 132) or surveillance (n = 129). Patients in the chemotherapy arm received four 21-day cycles of gemcitabine plus cisplatin or, when renal function was impaired, carboplatin.
With a median follow-up of 30.3 months, patients who received chemotherapy had a lower risk of disease recurrence or death, relative to counterparts who received only surveillance (hazard ratio, 0.45; P = .0001), with similar benefit across subgroups. The estimated 3-year disease-free survival rate was 71% in the chemotherapy arm and 46% in the surveillance arm. The median disease-free survival was 29.8 months and not reached, respectively.
The chemotherapy group also had a lower risk of metastasis or death when compared with the surveillance group (HR, 0.48; P = .0007). The 3-year event-free rates were 71% and 53%, respectively. Overall survival data are not yet mature.
“We acknowledge that disease-free survival is not regarded as a fully validated surrogate of overall survival after nephroureterectomy for UTUC,” the investigators wrote. “However, in a rare disease such as UTUC, a suitably powered trial with overall survival as the primary endpoint was not judged feasible. Although mature survival data (as a secondary endpoint) are not yet available, the large improvement in disease-free survival we noted for the primary endpoint, together with improved metastasis-free survival recorded as a secondary endpoint, strongly suggest that patients have better outcomes with chemotherapy than without.”
The incidence of acute grade 3 or worse treatment-emergent adverse events was 44% in the chemotherapy arm and 4% in the surveillance arm (P less than .0001). Quality of life was worse for the chemotherapy arm at 3 months (P = .0028), but that was no longer the case at 12 months (P = .20). There were no treatment-related deaths.
“[A]djuvant platinum-based chemotherapy should be adopted as a new standard of care for patients with locally advanced UTUC for whom systemic chemotherapy is not contraindicated,” the investigators recommended. “This regimen should be routinely considered for all patients in this population, and future studies should focus on combinations with novel agents in the adjuvant setting, which might further improve the prognosis for locally advanced UTUC.”
The trial was funded by Cancer Research UK. The authors disclosed relationships with numerous pharmaceutical companies.
SOURCE: Birtle A et al. Lancet. 2020 Mar 5. doi: 10.1016/S0140-6736(20)30415-3.