27O - Assessment of overall survival benefit from neoadjuvant chemotherapy in elderly HER-2 negative breast cancer patients: A population-based study

Background

Evidence suggests a significant survival improvement in breast cancer patients achieving pCR post-neoadjuvant therapy. The benefit for HER-2 negative seniors over 70 remains undetermined.

Methods

This study encompasses a cohort of patients aged 70 years and older with HER2-negative breast cancer, as recorded in the Surveillance, Epidemiology, and End Results (SEER) database from 2010 to 2015, examining the correlation between neoadjuvant and adjuvant therapies and overall survival (OS) to determine the prognostic advantage of neoadjuvant intervention in this demographic.

Results

We analyzed 169,306 patients aged 70+ with Her-2 negative breast cancer from the SEER database. Among them, 20,414 received neoadjuvant or adjuvant therapy. After excluding those with distant metastasis and those who did not undergo surgery, 9,029 patients remained: 1,559 received neoadjuvant chemotherapy and 7,470 received adjuvant chemotherapy. Propensity scores were calculated based on various factors, resulting in 1,422 patients in each group.The 10-year OS was 62.10% for the adjuvant group and 58.30% for the neoadjuvant group, showing a significant difference (P=0.018, HR 1.151, 95% CI 1.024-1.293). pCR status after neoadjuvant therapy did not correlate with survival benefit. The 10-year OS was 58.06% for pCR patients and 58.69% for non-pCR patients (P=0.301, HR 1.092, 95% CI 0.924-1.290). For ER+ or triple-negative patients, achieving pCR did not significantly improve 10-year OS compared to non-pCR patients (ER+:61.83% vs. 58.76%, P=0.425; TNBC: 53.58% vs. 58.42%, P=0.148). Neoadjuvant chemotherapy did not improve 10-year OS compared to adjuvant chemotherapy in triple-negative patients (54.55% vs. 55.01%, P=0.730, HR 1.033, 95% CI 0.860-1.240). For ER+ patients, adjuvant chemotherapy resulted in significantly higher 10-year OS compared to neoadjuvant chemotherapy (66.05% vs. 60.37%, P=0.006, HR 1.236, 95% CI 1.062-1.439).

Conclusions

For elderly HER-2 negative, breast cancer patients over 70, neoadjuvant chemotherapy does not provide a survival benefit. Therefore, its use in this demographic, especially for ER+ patients, should be approached with caution.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.