This study provides high-level evidence for de-escalating chemotherapy strategies in HER2-positive breast cancer, suggesting that carboplatin can be safely omitted in the context of dual-targeted therapy. It offers direct reference for optimizing individualized treatment regimens.
Literature Overview
The article titled 'Neoadjuvant Taxane Plus Trastuzumab and Pertuzumab With or Without Carboplatin in Human Epidermal Growth Factor Receptor 2–Positive Breast Cancer: The Randomized Noninferiority Phase III neoCARHP Trial', published in the Journal of Clinical Oncology, systematically investigates the efficacy and safety of a paclitaxel, trastuzumab, and pertuzumab (THP) regimen versus a carboplatin-containing regimen (TCbHP) in patients with stage II/III HER2-positive breast cancer. This multicenter, open-label, randomized phase III non-inferiority trial enrolled 774 patients to evaluate whether omitting carboplatin affects the pathological complete response (pCR) rate. Results showed pCR rates of 64.1% in the THP group and 65.9% in the TCbHP group, with the intergroup difference meeting non-inferiority criteria. Moreover, the THP group experienced significantly fewer grade 3–4 adverse events. This study provides strong support for the rational omission of carboplatin in clinical practice, particularly in patients at intermediate or low risk.Background Knowledge
HER2-positive breast cancer accounts for approximately 15%–20% of all breast cancers and is characterized by high aggressiveness and poor prognosis, historically posing significant treatment challenges. Since the introduction of the HER2-targeted agent trastuzumab, combination chemotherapy has substantially improved patient outcomes. The current standard neoadjuvant regimen involves a four-drug combination of taxane, carboplatin, trastuzumab, and pertuzumab (TCbHP). However, this regimen is associated with high hematologic toxicity, particularly carboplatin-induced neutropenia and thrombocytopenia, often leading to dose reductions or treatment interruptions. Although studies such as TRYPHAENA and GeparSixto support platinum-containing regimens, their necessity in lower-risk populations has long been questioned. Additionally, recent phase II trials suggest that dual-targeted therapy combined with taxane alone can achieve high pCR rates, indicating that chemotherapy intensity might be reduced. Therefore, exploring ways to reduce chemotherapy toxicity while maintaining efficacy has become a key challenge in HER2-positive breast cancer research. This study directly addresses that question: can carboplatin be safely omitted while retaining dual-targeted therapy? The topic targets a central controversy in current clinical practice and provides critical evidence for treatment de-escalation. pCR, as a surrogate endpoint in neoadjuvant therapy, is widely accepted for early efficacy assessment and is closely associated with long-term survival outcomes, particularly in the HER2-positive subtype.
Research Methods and Experiments
The study employed a multicenter, open-label, randomized, phase III non-inferiority design, enrolling 774 female patients with stage II/III HER2-positive breast cancer, who were randomly assigned in a 1:1 ratio to the THP group (n=387) or the TCbHP group (n=387). The primary endpoint was the pCR rate (ypT0/is ypN0) in the mITT population, with a non-inferiority margin set at -10%. The taxane (paclitaxel, docetaxel, or nab-paclitaxel) was selected by the investigator. The THP group received taxane plus trastuzumab and pertuzumab, while the TCbHP group additionally received carboplatin. All patients received six 3-weekly treatment cycles. Safety was assessed in the full treatment population. The study design was rigorous, using central randomization stratified by hormone receptor status and lymph node involvement to ensure group comparability. The primary analysis was conducted in the mITT population (n=766), with pCR rates and 95% CIs calculated using the Clopper-Pearson method, and intergroup differences assessed via the Newcombe-Wilson method. This approach minimized bias, employed sound statistical methods, and yielded highly reliable results.Key Conclusions and Perspectives
Research Significance and Prospects
This study provides high-quality, level I evidence for treatment de-escalation in HER2-positive breast cancer, challenging the notion that TCbHP is the only standard regimen. Omitting carboplatin not only reduces toxicity but also simplifies treatment and improves patient adherence, particularly in intermediate- or low-risk patients. Future efforts should integrate biomarkers such as HER2DX and 18F-FDG-PET to further refine the target population for precision de-escalation. Additionally, as antibody-drug conjugates (ADCs) like trastuzumab deruxtecan show promise in early-stage settings, future studies could explore their potential to replace chemotherapy altogether, further minimizing the use of traditional cytotoxic agents.
Conclusion
The neoCARHP trial provides crucial evidence-based guidance for neoadjuvant treatment strategies in early-stage HER2-positive breast cancer. The study confirms that taxane combined with dual-targeted therapy (THP) is non-inferior to carboplatin-containing regimens in terms of pCR rate, while significantly reducing the risk of grade 3–4 adverse events and serious adverse events. These results support the rational omission of carboplatin in clinical practice, especially for intermediate- or low-risk patients, enabling treatment de-escalation without compromising efficacy. From a translational research perspective, this study advances the implementation of personalized medicine, suggesting that in the future, patient selection for safe treatment de-escalation should integrate multidimensional information such as molecular subtypes and imaging-based metabolic responses. Furthermore, the study lays the foundation for exploring milder chemotherapy regimens or alternative strategies (e.g., antibody-drug conjugates). Ultimately, this research is expected to optimize the care system for HER2-positive breast cancer, enhancing treatment safety and quality of life, marking an important step toward precision medicine.
