The impact of neoadjuvant systemic therapy on breast conservation rates in patients with HER2-positive breast cancer: Surgical results from a phase II randomized controlled trial

BackgroundNeoadjuvant systemic therapy (NST) induces tumor shrinkage and boosts the chance of breast-conserving thearpy (BCT) in patients with breast cancer. However, only a few trials have evaluated the effect of NST in conversion from BCT ineligibility to BCT eligibility in HER2-positive breast cancer.MethodsWe conducted the surgical sub-study of a phase II randomized trial, which compared standard neoadjuvant treatment or an experimental treatment modified according to the interim Ki-67 evaluation in women with stage II or III HER2-positive breast cancer. The treating surgeons assessed eligibility for BCT before and after NST. We evaluated the change in BCT eligibility following NST. We also analyzed the type of surgery performed and the success rate of BCT.ResultsTwo hundred six patients were included in this study. Of these, 44.0% were considered BCT candidates at baseline, while 69.8% were deemed eligible for BCT after NST (P < 0.001). Among non-BCT candidates at baseline, 46% successfully converted to BCT candidates. Of 139 patients deemed eligible for BCT following NST, 84.2% attempted BCT, and successful BCT, defined as tumor-free at all surgical margins, was achieved in 96.8% of patients. Different treatment arms did not affect the rate of post-NST BCT eligibility (70.0% vs 69.7%).ConclusionsThis study demonstrated that NST resulted in an absolute increase of 25.8% in the rate of BCT eligibility in HER2-positive breast cancer. About a half of non-BCT candidates converted to BCT candidates. BCT was successful in most patients who attempted BCT. There were still patients who chose mastectomy even though they were deemed eligible for BCT. Patients considered BCT-ineligible due to large tumor size most likely converted to BCT-eligible with NST. On the other hand, NST had less impact on the surgical indication of patients with multicentric disease or probable poor cosmetic outcome.     

The first reported case of trastuzumab induced interstitial lung disease associated with anti-neutrophil cytoplasmic antibody vasculitis – A case report and a prospective cohort study on the usefulness of neutrophil derived biomarkers in monitoring vasculitis disease activity during follow-up

Targeted therapies against human epidermal growth factor receptor 2 (HER2) are associated with increased interstitial lung disease (ILD). Trastuzumab, lapatinib, pertuzumab, and trastuzumab emtansine have markedly extended HER2 breast cancer survival but current knowledge on how these HER2-targeted agents induce interstitial lung disease is still poorly defined due to limited cases in the literature. Physicians mostly managed this complication by dose interruption, dose de-escalation, or discontinuation with success. In 2019, the FDA had granted accelerated approval on trastuzumab deruxtecan (T-Dxd) in HER2 breast cancer in the late line setting. Severe ILD incidence rate was over ten percent and led to fatal outcomes in 2.2% of patients in the T-Dxd trial. Searching for biomarkers to detect ILD incidence before it becomes clinically fulminant or for treatment response monitoring is of high clinical value.A Case of life-threatening trastuzumab-induced ILD was encountered in our facility. The ILD was confirmed to be antineutrophil cytoplasmic antibody (ANCA) pulmonary capillaritis. The biomarker of neutrophil extracellular traps (NETs), serum MPO-DNA complex, showed a good correlation with the clinical severity. Soon after B cell depleting agent rituximab usage, the serum MPO-DNA outperformed ANCA autoantibody and maintained its correlation with clinical severity. In addition to the trastuzumab-induced ILD case, a prospective cohort in our facility also confirmed the usefulness of MPO-DNA in monitoring vasculitis activity. We postulated that upfront testing with biomarkers of vasculitis during HER2 targeted treatment with high ILD incidence may be beneficial in the future.     

Phase II study to investigate the efficacy of trastuzumab biosimilar (Herzuma®) plus treatment of physician's choice (TPC) in patients with heavily pretreated HER-2+ metastatic breast cancer (KCSG BR 18–14/KM10B)

We investigated the efficacy and safety of a trastuzumab biosimilar, Herzuma®, in combination with treatment of physician's choice (TPC) in patients with HER2+ metastatic breast cancer (MBC) who had failed at least two HER2 directed chemotherapies.     

曲妥珠单抗和帕妥珠单抗联合化疗对HER2阳性乳腺癌新辅助治疗的真实世界研究

目的 分析曲妥珠单抗(H)和帕妥珠单抗(P)联合化疗对HER2阳性乳腺癌新辅助治疗的疗效和安全性.方法 回顾性分析行HP联合化疗新辅助治疗并完成手术的HER2阳性乳腺癌患者的临床资料,主要研究终点为总体病理完全缓解(tpCR)(ypT0/isypN0),次要研究终点为乳腺病理完全缓解(bpCR)(ypT0/is)和腋窝...     

Role of receptor tyrosine kinases in gastric cancer： New targets for a selective therapy

Receptor tyrosine kinases (RTKs) such as the epidermal growth factor receptor family participate in several steps of tumor formation including proliferation and metastatic spread. Several known RTKs are upregulated in gastric cancer being prime targets of a tailored therapy. Only preliminary data exist, however, on the use of the currently clinically available drugs such as trastuzumab, cetuximab, bevacizumab, gefitinib, erlotinib, and imatinib in the setting of gastric cancer. Preclinical data suggest a potential benefit of their use, especially in combination with "conventional" cytostatic therapy. This review summarizes the current knowledge about their use in cancer therapy as well as new approaches and drugs to optimize treatment success.     

Antitumor activity of trastuzumab in combination with chemotherapy in human gastric cancer xenograft models

Purpose

To clarify the antitumor activity of trastuzumab and its potential as an effective treatment for gastric cancer patients.

Methods

Levels of HER2 expression in tumor tissues of gastric cancer cell lines were examined using immunohistochemistry (IHC), fluorescence in situ hybridization (FISH), and mRNA quantification. Efficacy of trastuzumab was examined as a single agent or in combination with chemotherapeutic agents widely used clinically for gastric cancers in HER2-overexpressing human gastric cancer xenograft models.

Results

Two of nine human gastric cancer xenograft models, NCI-N87 and 4-1ST, showed overexpression of HER2 mRNA and protein by IHC (HercepTest^®) and HER2 gene amplification by FISH (Pathvysion^®). HER2 protein showed potent staining in peripheral membranes, similar to the staining pattern of breast cancer. FISH scores were also comparable to those of breast cancer models. Trastuzumab as a single agent inhibited the tumor growth in both of the HER2-overexpressing models but not in the HER2-negative models, GXF97 and MKN-45. In any combination with capecitabine, cisplatin, irinotecan, docetaxel, or paclitaxel, trastuzumab showed more potent antitumor activity than the anticancer agents alone. A three-drug combination of capecitabine, cisplatin, and trastuzumab showed remarkable tumor growth inhibition. In NCI-N87 in vitro, trastuzumab showed direct antiproliferative activity according to cell count or crystal violet dying, and showed indirect antitumor activity such as antibody-dependent cellular cytotoxicity.

Conclusion

The antitumor activity of trastuzumab observed in human gastric cancer models warrants consideration of its use in clinical treatment regimens for human gastric cancer as a single agent or a combination drug with various chemotherapeutic agents.