Abstract 179P
Background
Undertreatment of breast cancer (BC) in elderly patients (pts) is frequent, but it’s impact on outcomes is not clear. We aimed to evaluate this association in elderly pts with early BC.
Methods
Pts > 70 y with BC treated with curative intent in a tertiary cancer center from 2009 to 2022 were evaluated. Indication of (neo)adjuvant chemotherapy (CT) was assessed according to institution guidelines based on clinical and pathological features. Undertreatment was considered if pts had an indication of CT, but did not receive it. Charlson index (ChI) was used to measure comorbidities. Endpoints evaluated were undertreatment rate, recurrence rate, breast cancer specific-survival (BCSS), overall survival (OS). Survival was estimated by Kaplan-Meier and compared by log-rank test stratified by age group, BC subtype, stage, and ChI. Cox regression was used for prognostic factors.
Results
1,455 pts were evaluated; Most pts were aged 70 to 80 y (71%), had HR-positive HER2-negative BC (79%), Stage II or III (69%) and mild comorbidities (ChI 1-2: 60%). (Neo)adjuvant CT would be indicated to 921 pts (63%) according to institution guidelines; 57% of them (n=531) did not receive CT (undertreatment), mainly (77%) due to age/ comorbidities. Undertreatment was higher in pts aged 80 – 90 y (83%) and > 90 y (100%) (P<0.001), and with more comorbidities (ChI ≥3-4: 66%) (P<0.001). Disease recurrence occurred in 8% of the undertreated pts vs 21% of those who received CT (P<0.001). 5-y BCSS and OS rates were 91.5% and 81.8%, and were not influenced by undertreatment (stratified log-rank: P = 0.389 and 0.217, respectively). Factors significantly associated with worse OS in a multivariable model were age group, triple-negative BC subtype, stage, and ChI. Undertreatment was not associated with OS in the multivariable model.
Conclusions
Although undertreatment rates were high in this elderly population, outcomes were not negatively impacted by it. Not offering (neo)adjuvant CT may be a proper choice for selected pts with early BC, considering their comorbidities and life-expectancy. Pts with HR-negative disease are underrepresented in this cohort and further investigation for this population is warranted.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
R. Colombo Bonadio: Financial Interests, Personal, Expert Testimony: Astrazeneca, Ache; Financial Interests, Personal, Research Grant: Novartis; Financial Interests, Personal, Other, Attending symposia: Roche; Financial Interests, Personal, Other, Education programs and symposia: Astrazeneca. L. Testa: Financial Interests, Personal, Advisory Role: MSD Oncology, Lilly, Daiichi Sankyo/AstraZeneca, Novartis; Financial Interests, Personal, Speaker’s Bureau: Novartis, Pfizer, MSD Oncology, Daiichi Sankyo/AstraZeneca, Lilly; Financial Interests, Institutional, Research Grant: Novartis; Financial Interests, Personal, Other, Travel, Accommodations, Expenses: Pfizer. All other authors have declared no conflicts of interest.