Neoadjuvant Therapy With Trastuzumab and Chemotherapy and the Resultant Pathologic Complete Response Observed in HER2 Positive Breast Cancer;a Systematic Review

This systematic review aimed to assess the effectiveness of neoadjuvant chemotherapy and Trastuzumab in achieving pathological complete response (pCR) in patients with HER2-positive breast cancer. The researchers identified nine clinical trials that met the inclusion criteria. These trials included patients with non-metastatic operable, locally advanced, or inflammatory breast cancer, and they evaluated the pCR as the primary or secondary endpoint.

The trials utilized different chemotherapy and targeted therapy regimens, along with varying dosages of Trastuzumab. The primary outcome of interest was the pCR rate, while other survival outcomes were not analyzed. Among the 1,209 patients who received neoadjuvant chemotherapy and Trastuzumab, the overall pCR rate was found to be 42%.

The review provided detailed information about the design of the selected trials, patient characteristics, disease staging, HER2 status, administered treatment regimens, and primary/secondary endpoints. It also mentioned slight variations in the definition of pCR across the trials.

Inclusion criteria

• Patients with breast cancer that was found to be HER2 positive were included
• Only patients who underwent neoadjuvant therapy were included
• All cytotoxic chemotherapy regimens were considered eligible for this systematic review given that the same drugs were given at the same dose in every trial.

Exclusion criteria

• Patients with metastatic breast cancer were not included in the systematic review
• Results from adjuvant therapy were excluded from this study.
• Only the most recent publication (and the most informative) was included if numerous publications of the same trial were retrieved or if there was a case mix between publications.