Real-world Outcomes of Neoadjuvant Dual HER2 Blockade with TCHP in Early and Locally Advanced HER2-Enriched Breast Cancer: Experience from a South Indian Tertiary Oncology Center.

BACKGROUND

HER2-enriched breast carcinomas are biologically aggressive but highly responsive to targeted therapy. Data on the real-world effectiveness of neoadjuvant docetaxel, carboplatin, trastuzumab, and pertuzumab (TCHP) from Indian oncology practices remain sparse.

OBJECTIVES

To assess pathological complete response (pCR), treatment-related toxicities (CTCAE v5.0), and survival outcomes among patients with nonmetastatic HER2-positive breast cancer receiving neoadjuvant TCHP.

MATERIALS AND

METHODS

A bidirectional observational analysis was conducted on 55 patients with HER2-positive nonmetastatic breast carcinoma who were treated at a tertiary oncology center. Patients received neoadjuvant TCHP followed by definitive surgery. Clinical response, radiological response, pCR, treatment compliance, toxicity, disease-free survival (DFS), and overall survival (OS) were evaluated. Statistical associations with pCR were analyzed using Fisher's exact test.

RESULTS

The median age of the patients was 47 years. Stage III disease was the most common (70.9%). Hormone receptor negativity was observed in 56% of the patients. Clinical complete response was achieved in 85% of the patients, whereas radiological complete remission occurred in 58%. A pCR was documented in 60% of the cohort. A significant correlation with pCR was observed for clinical response (p < 0.001), radiological response (p = 0.002), and uninterrupted treatment completion within 18 weeks (p = 0.013). Hormone receptor expression and baseline stage did not significantly influence pCR rates. Diarrhea and neutropenia were the predominant toxicities, whereas clinically relevant cardiotoxicity was not encountered. At a median follow-up of 29 months, the estimated 3-year DFS and OS were 95% and 97.2%, respectively.

CONCLUSION

Neoadjuvant TCHP demonstrated substantial pathological response rates, acceptable tolerability, and encouraging survival outcomes in HER2-positive breast cancer. Adherence to the planned treatment timeline significantly influenced therapeutic efficacy.