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Journal of Clinical Oncology, 2007 ASCO Annual Meeting Proceedings (Post-Meeting Edition).
Vol 25, No 18S (June 20 Supplement), 2007: 4523
© 2007 American Society of Clinical Oncology
Correlation of RTOG 9704 (adjuvant therapy (rx) of pancreatic adenocarcinoma (pan ca)) radiation therapy quality assurance scores (RTQASc) with survival (S)
R. A. Abrams,
K. A. Winter,
W. F. Regine,
H. Safran,
J. P. Hoffman,
A. A. Konski,
A. B. Benson,
J. S. Macdonald,
T. A. Rich and
C. G. Willett
Rush Univ Medical Center, Chicago, IL; Radiation Therapy Oncology Group, Philadelphia, PA; University of Maryland, Baltimore, MD; Miriam Hospital, Providence, RI; Fox Chase Cancer Center, Philadelphia, PA; Northwestern University, Chicago, IL; St. Vincents Cancer Care Center, Castine, ME; University of Virginia, Charlottesville, VA; Duke University Medical Center, Durham, NC
4523
Background: RTOG 9704 demonstrated a marginal S advantage (p=0.054) in multivariate analysis (MVA) of Gemcitabine (G) over 5FU before and after 5FU+RT for patients (pts) with pan ca resected for cure from the pan head but not from non-head sites (ASCO 2006, ASTRO 2006). This analysis was undertaken to assess the impact of RTQASc on S, S by treatment (rx) arm, and toxicity by rx arm. Methods: This is a secondary analysis of a prospective, randomized, phase III trial of the RTOG, ECOG, and SWOG. RTQASc was graded as per protocol (PP) or less than (<) PP. Using prospectively defined guidelines, <PP scores were variation acceptable (VA), variation unacceptable (VU), or incomplete/not evaluable (I/NE). I/NE pts were excluded from further analysis. Toxicities were scored by CTC, v 2.0. S is expressed as median S in yrs. Results: 416 pts had RTQASc of PP (216, 52%) or <PP (200, 48%; 42% VA, 6% VU). Frequency of PP and <PP did not differ by rx arm (PP = 55% on 5FU arm and 48% on G arm). Looking at PP vs <PP frequency of Grade 3+ Heme and Non- Heme toxicity did not vary significantly on the 5FU arm but did show a trend of < toxicity for PP pts on the G arm (Table). In contrast, S was increased for all (head, non-head) PP pts (median S 1.74 vs 1.47 yrs, p=0.019) and, in MVA, score of PP significantly impacted on S (p=0.02) but rx arm did not. PP and <PP S curves began to diverge at 1415 months post surgery. For head pts, in MVA, RTQASc (PP superior to <PP) and rx arm (G superior to 5FU) both correlated with S (p=0.04, p=0.03, respectively). On the G arm PP pts had S of 1.89 yrs, significantly > than S of VA (1.41yrs) and VU (1.37yrs) pts. Conclusions: In this study prospectively defined RTQASc significantly correlated with S and effect of rx arm on S and showed a weaker effect on toxicity (G arm only). Timing of appearance of RTQASc effect on S implies effect on tumor control. In this context failure to consider RTQASc may confound observed outcomes and confuse correct understanding of the importance of RT.
No significant financial relationships to disclose.
Abstract presentation from the 2007 ASCO Annual Meeting
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