A phase 2 clinical trial of sequential neoadjuvant chemotherapy with ifosfamide, doxorubicin, and gemcitabine followed by cisplatin, gemcitabine, and ifosfamide in locally advanced urothelial cancer: final results

Abstract

Background: Neoadjuvant chemotherapy improves the survival of patients with high-risk urothelial cancer. However, the lack of curative alternatives to cisplatin-based chemotherapy is limiting for patients with neuropathy or hearing loss. Sequential chemotherapy also has not been well studied in the neoadjuvant setting. The authors explored sequential neoadjuvant ifosfamide-based chemotherapy in a patient cohort at high risk of noncurative cystectomy.

Methods: Patients with muscle-invasive cancer and lymphovascular invasion, hydronephrosis, clinical T3b and T4a (cT3b-4a) disease (defined as a 3-dimensional mass on examination under anesthetic or invasion into local organs), micropapillary tumors, or upper tract disease received 3 cycles of combined ifosfamide, doxorubicin, and gemcitabine followed by 4 cycles of combined cisplatin, gemcitabine, and ifosfamide. The primary endpoint was downstaging to pT1N0M0 disease or lower.

Results: At a median follow-up of 85.3 months, the 5-year overall survival (OS) and disease-specific survival (DSS) rates for all 65 patients were 63% and 68%, respectively (95% confidence interval: 5-year OS rate, 0.52%-0.76%; 5-year DSS rate, 0.58%-0.81%). Pathologic downstaging to pT1N0 disease or lower occurred in 50% of patients who underwent cystectomy and in 60% of patients who underwent nephroureterectomy and was correlated with the 5-year OS rate (pT1N0 disease or lower, 87%; pT2-pT3aN0 disease, 67%; and pT3b disease or higher or lymph node-negative disease, 27%; P ≤ .001 for pT1 or lower vs pT2 or higher). Variant histology was associated with an inferior 5-year DSS rate (50% vs 83% in pure transitional cell carcinoma; P = .02). The most frequent grade 3 toxicities were infection (38%), febrile neutropenia (22%), and mucositis (18%). There were 3 grade 4 toxicities (myocardial infarction, thrombocytopenia, and vomiting) and 1 grade 5 toxicity in a patient who refused antibiotics for pneumonia.

Conclusions: Sequential therapy was active and maintained the historic expectation of achieving a cure. The current results strongly reinforced previous experience suggesting that pathologic downstaging to pT1N0 disease or less is a useful surrogate for eventual cure in patients with urothelial cancer.

Figure 1

Overall survival distribution by pathologic stage. For all patients enrolled, pathologic down-staging to ≤ pT1N0 occurred in 51% of patients. Down-staging correlated with improvement in overall survival (p ≤ 0.001 comparing ≤pT3aN0 with ≥pT3b, or N+.) Patients down-staged to ≤pT1N0, pT2-3aN0, and ≥pT3b or N+, had a 5-year OS of 86%, 67%, and 27%, respectively.

Figure 2

Overall survival distribution. For all patients enrolled, the 5-year overall survival was 63% (95% confidence intervals shown).

Figure 3

Disease-specific survival by histology. For all patients enrolled, patients with a pure transitional cell histology had a longer disease-specific survival, as compared with patients whose tumors expressed variant histology (DSS 83%, and 50%, respectively, log-rank p = 0.02).