Powell, Mark

4627 Background: E4201 compared radiation and gemcitabine (RT+Gem) versus Gem alone in LAPC. The primary endpoint was overall survival; secondary objectives included: objective response rate (RR), progression-free survival (PFS), toxicity and QOL. We previously reported that RT+Gem was associated with improved overall survival compared with Gem alone [median survival time, 11 months and 9.2 months, respectively; p=0.034], without impact in RR or PFS. (ASCO 2008, abstract # 4506). We now report on QOL as measured by the Hep subscale from the FACT-Hepatobiliary [FACT-Hep] between both arms. Methods: Eligible patients had LAPC adenocarcinoma, PS <2, without prior therapy. They were randomized to Arm A: Gem alone (1,000 mg/m2/week x 3, every 4 weeks, 7 cycles), or Arm B: RT (50.4Gy/28 fractions) plus Gem (600 mg/m2/weekly x 6) followed by 5 cycles of Gem alone (1,000 mg/m2/weekly x 3 every 4 wks). The FACT-Hep was administered at baseline (before starting induction), 6 weeks (immediately after completing induction), week 16 (Arm A) or week 15 (Arm B) mid-consolidation, and at 9 months. Results: From April, 2003 to December, 2005, 74 patients were enrolled, 71 were eligible [37 Arm A; 34 Arm B]. Grade ≥3 was reported in 80% and 82.4% in ARM A and B, respectively (p=1.00). Grade IV toxicities, mainly gastrointestinal and hematologic, were more common in ARM B (41.2% vs 5.7%, p=<0.0001). QOL compliance declined over time, most commonly attributable to either patients or staff choosing not to complete or administer the instrument due to declining health (96%, 69%, 60%, and 40% at baseline, week 6, 15/16 weeks and 9 months, respectively). Within Arm B, QoL scores dropped significantly from baseline to 6 weeks. By week 15, QoL scores for patients on Arm B rebounded to levels similar to baseline. Two-sided Wilcoxon rank sum tests failed to suggest differences in median FACT-Hep subscale score between treatment arms at any of the four time-points (alpha = 0.10). Conclusions: RT+Gem is associated with an overall survival benefit without apparent long term adverse impact on QOL when compared with Gem alone. No significant financial relationships to disclose.

4530 Background: EAC has eluded cure even with platin-based CRT. Stratifying pts by likelihood of success is one approach to improving outcomes. We assessed whether SNPs in DNA repair paths are associated with complete pathologic response (pCR) in EAC pts who received C-based CRT followed by surgery. Methods: Patients and specimens: Pretreatment biopsy or post-CRT resection samples were obtained from pts (EAC, stage II-IVa) treated on a randomized phase II trial, E1201 (n=86), of preop CRT (RT to 45 Gy). Arm A: Preop C 30 mg/m2 + irinotecan (I) 50 mg/m2 days (d) 1, 8, 22, 29 with RT. Post-op C 30 mg/m2 + I 65 mg/m2 d 1, 8 q21 days x 3. Arm B: Preop C 30 mg/m2 + paclitaxel (P) 50 mg/m2 d 1, 8, 15, 22, 29 with RT. Post-op C 75 mg/m2 + P 175 mg/m2 d 1 q21 days x 3. Clinical outcome - pCR: (A) 14% [95% CI 5.5%, 28.5%]; (B) 16% [95% CI 6.7%, 30.1%]. Median overall survival (OS): (A) 34.9 m (months) [90% CI 23.5, not reached]; (B) 20.9 m [90% CI 17.4, 46.7]. Experimental procedure: Normal tissue was microdissected from unstained sections of paraffin-embedded tissue. DNA was extracted (Qiagen). Genotyping was performed by matrix-assisted laser desorption/ionization time-of-flight (Sequenom) for all SNPs. Each SNP was dichotomized a priori into: (1) major homozygote vs (2) minor (heterozygote plus minor homozygote) allele groups. Data analysis was performed centrally, with lab investigators blinded to clinical data. Exact logistic regression was used to derive ORs for non-pCR, using the major homozygote as the reference (2-sided p values). Results: Germline DNA was available in 68 pts; 60 were eligible and began therapy ( Table ). Conclusions: In this homogenous, well-defined cohort, the XRCC1 Arg399Gln minor allele group was associated with lower pCR (p=0.06). Lab data on a panel of additional SNPs have been collected and are under analysis for presentation at the meeting. [Table: see text] [Table: see text]