KEY TAKEAWAYS
- The study aimed to evaluate the long-term outcomes of omitting chemotherapy for postmenopausal women with specific breast cancer types in diverse populations.
- Results showed simulation modeling found minimal chemotherapy benefit in premenopausal women, with no benefit in postmenopausal women.
A recent trial demonstrated that postmenopausal women with hormone receptor-positive, HER2-negative, lymph node-positive (1-3 nodes) breast cancer and a 21-gene recurrence score of ≤ 25 could safely forgo chemotherapy.
Kaitlyn M. Wojcik aimed to address the gap in data regarding the long-term outcomes of omitting chemotherapy for this patient population in real-world settings, including diverse demographic groups.
Researchers used a proven simulation model to simulate outcomes for women with early-stage breast cancer in the U.S. They pulled data from cancer registries, meta-analyses, and clinical trials. The model assessed the impact of skipping chemotherapy on 10-year distant recurrence-free survival (RFS), life years, and quality-adjusted life years (QALYs), with a 3% discount on QALYs. They also looked at results by race and ethnicity and performed sensitivity tests on various inputs. The model was checked against the RxPONDER trial data.
The results indicated that the 10-year distant RFS survival for premenopausal women was 85.3% with chemotherapy and endocrine therapy versus 80.1% with only endocrine therapy. Chemotherapy added an estimated 2.1 life-years and 0.6 QALYs. Postmenopausal women did not benefit from chemotherapy.
Although chemotherapy’s absolute benefit did not vary by race or ethnicity, there were differences in distant RFS, life years, and QALYs among different groups. Sensitivity analyses confirmed these findings, and the model closely matched the RxPONDER trial results.
The study concluded that simulation modeling reveals a minor chemotherapy benefit for premenopausal women, with no benefit for postmenopausal women. This approach effectively extends trial data to assess population-level outcomes.
The study was funded by the National Institutes of Health and the National Institutes of Health Distinguished Scholars program.
Source: https://pubmed.ncbi.nlm.nih.gov/39118050/
Wojcik KM, Caswell-Jin JL, Wilson OWA, et al. (2024). “The population-level effects of omitting chemotherapy guided by a 21-gene expression assay in node-positive breast cancer: a simulation modeling study.” BMC Cancer. 2024 Aug 8;24(1):975. doi: 10.1186/s12885-024-12719-3. PMID: 39118050; PMCID: PMC11308572.
