Paclitaxel (T) plus ifosfamide (I) followed by high-dose carboplatin (C) and etoposide (E) with autologous stem cell support for patients (pts) with previously treated germ cell tumors (GCT): TI-CE results and prognostic factor analysis in 107 pts

Abstract

5027 Background: Pts with incomplete response (IR) to first-line chemotherapy or relapsed primary mediastinal non-seminomatous GCT (NSGCT) have <10% 3-year (yr) survival with conventional-dose salvage regimens (Cancer. 67:1305). The doses, schedule, and safety of TI-CE in this population were previously reported (J Clin Oncol. 25: 85). Efficacy and prognostic factor analysis are now presented. Methods: Phase I/II trial of TI-CE conducted in GCT pts with progressive disease following chemotherapy and unfavorable prognostic features (extragonadal primary site, IR to first-line therapy, or relapse/IR to ifosfamide/cisplatin-based conventional-dose salvage). Univariate and multivariate analyses of prognostic factors were performed. Einhorn (N Eng J Med. 357:340) and Beyer (J Clin Oncol. 14: 263) prognostic models were also assessed. Results: Of 107 pts, primary site was testis in 72, mediastinum (all NSGCT) in 21, and other in 14. 81 had 1 prior line of therapy and 26 had ≥2. 79 were platinum-refractory and 7 had late relapses. A complete response was achieved in 54 (50%) and partial response with negative markers in 8 (8%). 5-yr disease-free survival (DFS) was 47% and overall survival 52% with a median follow-up of 61 months (m). No relapses occurred after 2 yrs. 5/21 (24%) primary mediastinal NSGCT and 2/7 late relapses are continuously disease-free. On multivariate analysis, primary mediastinal site (p = 0.0002), ≥2 lines of prior therapy (p = 0.0005), baseline HCG >1000 (p = 0.01), and lung metastases (p = 0.02) significantly predicted adverse DFS. By Beyer model, 79% were intermediate and 21% poor risk (0 good risk). DFS was better for intermediate than poor risk pts (p < 0.002), with 2-year rates of 54% and 23%, respectively. By Einhorn model, 15% pts were good, 38% intermediate, and 47% poor risk; good/intermediate risk pts had superior DFS compared to poor risk pts (p < 0.05) with DFS at 2 yrs of 69% vs. 44%. Conclusions: TI-CE is effective salvage therapy for GCT pts with poor prognostic features. Mediastinal primary site and ≥2 lines of prior therapy were most predictive of adverse DFS. Beyer & Einhorn models can assist in predicting outcome. No significant financial relationships to disclose.