Abstract GS4-01: Ten-year results from NRG Oncology/NSABP B-42: A randomized, double-blinded, placebo-controlled clinical trial of extended adjuvant endocrine therapy with letrozole (L) in postmenopausal women with hormone-receptor+ breast cancer (BC) who have completed previous adjuvant therapy with an aromatase inhibitor (AI)
Bibliographic record
Abstract
Abstract Background: In the NSABP B-42 trial we aimed to determine whether 5 yrs of letrozole (L) v placebo (P) improves DFS in patients (pts) who have completed 5 yrs of hormonal therapy (tx). 3966 postmenopausal pts with stage I-III, hormone-receptor+ BC, disease-free after 5 yrs of an AI or tamoxifen (TAM) for ≤3 years → AI for the remainder of 5 yrs, were randomized to L 2.5 mg or P daily for an additional 5 yrs. In the primary analyses the beneficial effect of extended tx with 5 yrs of L did not reach statistical significance on disease-free survival (DFS). There was no significant improvement in overall survival (OS) with L, but L did provide a significant improvement in breast-cancer-free interval (BCFI) and distant recurrence (DR). The updated results based on the data received as of April 30, 2019, are presented here. Methods: Stratification was by pathological nodal status, prior adjuvant TAM or not, and baseline dexa T scores (>-2.0, ≤-2.0 SD). Primary endpoint was DFS including local, regional, distant recurrence, second primary cancers, and deaths from any cause as first event. Secondary endpoints included OS, BCFI (including recurrence or contralateral BC as first event), DR, osteoporotic fractures (OF), and arterial thrombotic (AT) events. Differences in DFS, OS, BCFI, DR, OF, and AT between L and P were assessed by the stratified log-rank tests and Cox proportional hazards models. Statistical significance level was set at 0.05. Results: Median follow-up for 3923 pts included in the current analyses was 9.3 yrs. As of 4/30/19, 890 DFS events had occurred (L=411, P=479); L resulted in a statistically significant increase in DFS v P (HR=0.84; 95% CI 0.74, 0.96; p=0.011); 10-yr DFS was L=76.1% and P=72.1%. The effect of L was statistically significantly different for pts with baseline T score ≤-2.0 (HR=0.63; 95% CI 0.49, 0.82) v those with a score >-2.0 (HR=0.93; 95% CI 0.80, 1.09) (interaction p=0.013). 495 deaths occurred (L=243, P=252); there was no statistically significant difference in OS with L v P (HR=0.97, 95% CI 0.82, 1.16; p=0.77); 10-yr OS was L=86.1% and P=85.5%. 413 BCFI events occurred (L=178, P=235); L v P resulted in a statistically significant 26% decrease in BCFI events (HR=0.74, 95% CI 0.61, 0.91; p=0.003); 10-yr cumulative incidence (Cum In) of BCFI was L=10.3% v P=13.3%. 229 DRs occurred (L=96, P=133); L v P resulted in a statistically significant 29% reduction in DR (HR=0.71, 95% CI 0.55, 0.93; p=0.01); 10-yr Cum In of DR was L=5.7% v P=7.5%. There were 209 OF (L=109, P=100). There were no significant differences in time to OF with L v P (P=0.46). Cum In of OF through 10 yrs was L=6.5% v P=6.4%. There were 154 AT events (L=82, P=72). Treatment with L did not result in an overall statistically significant increase in AT events compared to P (p=0.38). Cum In of AT through 10 yrs was L=4.7% v P=4.1%. Conclusions: The effect of extended tx with 5 yrs of L on DFS persisted in the updated analyses and reached statistical significance. There was no significant improvement in OS with L, but L continued to provide a significant improvement in BCFI and DR. Support: U10CA180868, -180822; UG1CA189867; Korea Health Technology R&D Project; Novartis. Citation Format: Eleftherios P Mamounas, Hanna Bandos, Barry C Lembersky, Jeon Hyeon Jeong, Charles E Geyer, Jr, Priya Rastogi, Louis Fehrenbacher, Mark L Graham, Stephen K Chia, Adam M Brufsky, Janice M Walshe, Gamini S Soori, Shaker R Dakhil, Thomas E Seay, James L Wade, III, Edward C McCarron, Soonmyung Paik, Sandra M Swain, D Lawerence Wickerham, Norman Wolmark. Ten-year results from NRG Oncology/NSABP B-42: A randomized, double-blinded, placebo-controlled clinical trial of extended adjuvant endocrine therapy with letrozole (L) in postmenopausal women with hormone-receptor+ breast cancer (BC) who have completed previous adjuvant therapy with an aromatase inhibitor (AI) [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr GS4-01.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.003 | 0.002 |
| Meta-epidemiology (narrow) | 0.003 | 0.001 |
| Meta-epidemiology (broad) | 0.004 | 0.002 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.002 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.003 | 0.004 |
| Insufficient payload (model declined to judge) | 0.012 | 0.002 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".