![]() Krystel-Whittemore M, Xu J, Brogi E, et al. Krystel-Whittemore and colleagues in Breast Cancer Research and Treatment, “and if confirmed, further work is needed to determine the degree of benefit provided by anti-HER2 therapy in patients with HER2 gene amplification without HER2 protein overexpression.” “We look forward to other studies to validate our findings,” noted Dr. The rate of pCR in the subset of patients with HER2 amplification by FISH in the absence of HER2 protein overexpression was significantly lower.” “The excellent response to HER2-targeted therapies among HER2-positive breast cancer was mainly seen in patients with HER2 IHC 3+ tumors. “In summary, our study demonstrated that HER2 protein expression level (IHC 3+) had significant impact on pCR, along with grade 3 histology, hormone receptor-negative status, and use of trastuzumab and pertuzumab,” the authors explained in Breast Cancer Research and Treatment. Krystel-Whittemore and colleagues report increased pCR rates to standard chemotherapy plus HER2-targeted therapy among patients with HER2 overexpression compared with patients with HER2 amplification by FISH in the absence of HER2 overexpression. A trend toward significance was observed for higher pCR rates among ER-negative tumors compared with ER-positive tumors. High-grade histology, PR-negative status, and dual anti-HER2 therapy also remained significantly associated with higher pCR rates on multivariate analysis. HER2 protein overexpression remained a significant predictor of pCR on multivariate analysis. Patients with HER2 amplification by FISH in the absence of HER2 protein overexpression were older, had lower-grade tumors, and had more frequent ER-positive and PR-positive status compared with patients with HER2 protein overexpression. In pretreatment biopsies, HER2 IHC results were positive in 81%, equivocal in 13%, and negative in 0.5%. Over 90% of patients received dual anti-HER2 regimens with trastuzumab and pertuzumab. The neoadjuvant chemotherapy regimen of choice was dose-dense doxorubicin and cyclophosphamide followed by paclitaxel in 82.5%, docetaxel and carboplatin in 10%, and other regimens in 7.5%. The average age at diagnosis was 51 years. Overall, 560 consecutive patients with HER2-positive invasive breast cancer were included. The definition of pCR for this study was no residual invasive carcinoma in the breast and axillary lymph nodes (ypT0/is ypN0) upon surgical resection. ![]() HER2 IHC 1+ cases were tested by HER2 FISH when there were discrepant outside laboratory results.Ĭlinicopathologic characteristics, HER2 assessment methods, chemotherapy, HER2-targeted therapy, and pathologic response were also evaluated. All HER2 IHC equivocal cases went on to reflex HER2 dual-probe FISH assay. Using the 2018 ASCO/CAP guidelines, HER2 IHC was scored as negative (0+ or 1+), equivocal (2+ or 1+ to 2+), or positive (3+). Positivity for ER and PR was defined as 1% or greater nuclear staining in tumor cells. All patients received trastuzumab or dual trastuzumab/pertuzumab combined with standard chemotherapy.įDA-approved assays were used to assess estrogen receptor (ER), PR, and HER2 via IHC and HER2 via dual-probe fluorescence in situ hybridization (FISH). This retrospective study included patients with HER2-positive invasive breast cancer who received neoadjuvant systemic therapy and surgical resection at Memorial Sloan Kettering Cancer Center between January 2013 and May 2018. “The aim of this study was to evaluate factors associated with pCR among patients with HER2-positive breast cancer, and to compare the pCR rates between breast cancers with HER2 protein overexpression (IHC 3+) and with HER2 gene amplification by ISH in the absence of protein overexpression,” Melissa Krystel-Whittemore, MD, of Massachusetts General Hospital, Boston, and colleagues noted in Breast Cancer Research and Treatment. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |