Cambridge Translational Cancer Research Ovarian Study 01 (CTCR-OV01): Expression profiling of advanced epithelial ovarian cancer (EOC) to predict chemotherapy response. A randomised phase II trial design with prospective translational endpoints.

15018 Methods: CTCR-OV01 is a randomised phase II neoadjuvant study in stage III-IV epithelial ovarian cancer (EOC). Patients (pts) were consented for diagnostic and fresh tissue research biopsies, and after diagnosis was confirmed, were randomised (1:1) to: Arm A: Carboplatin AUC 7 every 3 weeks (C) × 3 cycles (cy); then interval debulking surgery (IDS); then C AUC 6 with paclitaxel 175 mg/m2 q 3w (CT) × 3 cy; and finally paclitaxel 175 mg/m2 q 3w (T) × 3 cy. Arm B: T × 3 cy; IDS; CT × 3 cy; C × 3 cy. At IDS further fresh tissue samples were collected. Clinical Endpoints: (i) Partial response rate after three cycles of chemotherapy based on CA125 (CA125 RR) and CT scan (CT RR). (ii) Median progression-free survival (PFS). Translational endpoints: Candidate genes and molecular profiles as predictive markers of response/resistance to C and T. RESULTS Jan '02-Dec '04, 48 pts were randomised in a single centre study. 4 patients were excluded from analysis (3pts severe toxicity; 1pt incorrect histopathology), leaving 44 patients (21pts A/23 pts B). Median age 60 yr (range 36-75 yrs); 42/44 serous papillary histology; stage III/IV = 77%/23%; grade I/II/III = 2%/34%/64%. All prognostic factors were well balanced between treatment arms. Median follow-up is 22 months (IQR 17-33.5). CA125 RR to pre-operative chemotherapy was A/B = 65%/60% (p = 1). CT RR was A/B = 47%/35% (p = 0.15). CA125 RR, was significantly associated with improvement in progression-free survival (PFS) compared to non-responders (17.3 v 12.4 months; log rank test p = 0.027). Optimal debulking surgery was possible in A/B = 53%/63%. Median PFS was 14 months (m) (A/B = 13 m/14 m (p = 0.53)). Supervised analysis of Affymetrix expression data showed significant enrichment for differential extracellular gene expression in paclitaxel resistant patients. CONCLUSIONS Prospective controlled randomized trials using neoadjuvant treatment are ideally suited for translational research in EOC and provide unique sample sets molecular analysis. No significant financial relationships to disclose.