Wednesday, November 22, 2023 1. PA6 - Prediction of Adjuvant Gemcitabine Sensitivity in Resectable Pancreatic Adenocarcinoma Using the GemPred RNA Signature: An Ancillary Study of the PRODIGE-24/CCTG PA6 Clinical Trial (ONLINE). Nicolle R, Bachet J-B, Harlé A, Iovanna J, Hammel P, Rebours V, Turpin A, Abdelghani MB, Wei A, Mitry E, Lopez A, Biagi J, François E, Artru P, Lambert A, Renouf DJ, Monard L, Mauduit M, Dusetti N, Conroy T, Cros J. Journal of Clinical Oncology 2023. https://ascopubs.org/doi/abs/10.1200/JCO.22.02668 This ancillary study of a phase III randomized trial demonstrates that among the quarter of patients with a GemPred-positive transcriptomic signature, survival was comparable with that of mFOLFIRINOX, whereas those receiving adjuvant gemcitabine had fewer adverse events. Radiotherapy to regional nodes in early breast cancer: an individual patient data meta-analysis of 14,324 women in 16 trials (ONLINE). 2. MA20 - Radiotherapy to regional nodes in early breast cancer: an individual patient data meta-analysis of 14 324 women in 16 trials Early Breast Cancer Trialists' Collaborative Group (EBCTCG). The Lancet 2023. https://doi.org/10.1016/S0140-6736(23)01082-6 Radiotherapy has become much better targeted since the 1980s, improving both safety and efficacy. In breast cancer, radiotherapy to regional lymph nodes aims to reduce risks of recurrence and death. Its effects have been studied in randomised trials, some before the 1980s and some after. The study aimed to assess the effects of regional node radiotherapy in these two eras. The study results found 17 eligible trials, 16 of which had available data (for 14 324 participants), and one of which (henceforth excluded), had unavailable data (for 165 participants). In the eight newer trials (12 167 patients), which started during 1989–2008, regional node radiotherapy significantly reduced recurrence (rate ratio 0·88, 95% CI 0·81–0·95; p=0·0008). The main effect was on distant recurrence as few regional node recurrences were reported. Radiotherapy significantly reduced breast cancer mortality (RR 0·87, 95% CI 0·80–0·94; p=0·0010), with no significant effect on non-breast-cancer mortality (0·97, 0·84–1·11; p=0·63), leading to significantly reduced all-cause mortality (0·90, 0·84–0·96; p=0·0022). In an illustrative calculation, estimated absolute reductions in 15-year breast cancer mortality were 1·6% for women with no positive axillary nodes, 2·7% for those with one to three positive axillary nodes, and 4·5% for those with four or more positive axillary nodes. In the eight older trials (2157 patients), which started during 1961–78, regional node radiotherapy had little effect on breast cancer mortality (RR 1·04, 95% CI 0·91–1·20; p=0·55), but significantly increased non-breast-cancer mortality (1·42, 1·18–1·71; p=0·00023), with risk mainly after year 20, and all-cause mortality (1·17, 1·04–1·31; p=0·0067).
