The Prognostic Significance of Micrometastases in Breast Cancer: A SEER Population-Based Analysis

Introduction The prognostic significance of lymph node micrometastases in breast cancer is controversial. We hypothesized that the survival of patients with solely micrometastatic disease (N1mi) would be intermediate to patients with 1–3 tumor-positive lymph nodes (N1) and those with no positive lymph nodes (N0). Methods We queried the surveillance, epidemiology and end results (SEER) database for all patients between 1992 and 2003 with invasive ductal or lobular breast cancer without distant metastases and ≤3 axillary nodes with macroscopic disease. Patients were stratified by nodal involvement and compared using the Kaplan–Meier method. Cox proportional hazards regression was utilized to compare survival after adjusting for patient and tumor characteristics. Results Between 1992 and 2003, N1mi diagnoses increased from 2.3% to 7% among the 209,720 study patients (p < 0.001). In a T-stage stratified univariate analysis, N1mi patients had a worse prognosis in T2 lesions. On multivariate analysis, N1mi remained a significant prognostic indicator across all patients (p < 0.0001) with a hazard ratio of 1.35 compared to N0 disease and 0.82 compared to N1 disease. Other negative prognostic factors included male gender, estrogen-receptor negativity, progesterone-receptor negativity, lobular histology, higher grade, older age, higher T-stage, and diagnosis in an earlier time period. Conclusion Nodal micrometastasis of breast cancer carries a prognosis intermediate to N0 and N1 disease, even after adjusting for tumor- and patient-related factors. Prospective study is warranted and the results of pending trials are highly anticipated. Until then adjuvant therapy trials should consider using N1mi as a stratification factor when determining nodal status.     

Safety and Clinical Evaluation of Dual Inhibition with Pertuzumab and Trastuzumab Biosimilar SB3 in HER2-Positive Breast Cancer Patients

BackgroundThe addition of trastuzumab to standard chemotherapy has improved survival in patients with HER2-positive breast cancer in neoadjuvant, adjuvant, and metastatic settings. In higher tumor stages, the addition of pertuzumab is now a standard of care and associated with a favorable toxicity profile. We evaluated the safety and efficacy of the trastuzumab biosimilar SB3 in combination with pertuzumab in HER2-positive breast cancer patients.MethodsSeventy-eight patients with HER2-positive breast cancer treated at the Division of Oncology at the Medical University of Graz were included. Summary measures are reported as medians (25th to 75th percentile) for continuous variables and as absolute frequencies (%) for count data.ResultsThirty-five patients received a median of 4 (3–7) cycles of trastuzumab biosimilar SB3 plus pertuzumab. All patients had a normal baseline left ventricular ejection fraction (LVEF; >50%) prior to the initiation of SB3 plus pertuzumab treatment with a median LVEF of 60% (60–65). Twenty-one patients had a median absolute LVEF decline of 1% (−5 to 0). Two patients (5.7%) had a LVEF reduction ≤50%, but none ≥10%. There were no unexpected adverse events. Twenty-two of 35 patients (63%) were treated with trastuzumab biosimilar SB3 and pertuzumab in the neoadjuvant setting and 11 patients (50%) achieved a pathological complete response. The safety and the efficacy in this setting was comparable to the trastuzumab plus pertuzumab combination in neoadjuvantly treated matched samples.ConclusionIn this series of HER2-positive breast cancer patients, the combination of SB3 plus pertuzumab was consistent with the known safety and efficacy profile of trastuzumab and pertuzumab combination.     

Prognostic significance of germline BRCA mutations in patients with HER2-POSITIVE breast cancer

BackgroundHER2-positive breast cancers are rare amongst BRCA mutation carriers. No data exist regarding clinicopathological characteristics and prognosis of this subgroup of patients.Materials and methodsUsing a retrospective matched cohort design, we collected data from 700 women who were diagnosed with operable invasive breast cancer from January 2006 to December 2016 and were screened for germline BRCA mutations. Clinicopathological features and survival rates were analyzed by BRCA and HER2 status.ResultsOne hundred and fifteen HER2-positive/BRCA mutated cases were evaluated in comparison to the three control groups: HER2-positive/BRCA wild type (n = 129), HER2-negative/BRCA mutated (n = 222), HER2-negative/BRCA wild type (n = 234). HER2-positive breast cancers were more likely to have high histologic grade and high proliferation rate than HER2-negative neoplasms, regardless of BRCA mutation status. An interaction between BRCA mutations and HER2-positive status was found to correlate with worse survival after adjusting for prognostic variables (HR = 3.4; 95% CI: 1.3–16.7).ConclusionsCo-occurrence of BRCA mutations and HER2-positive status is a poor prognostic factor in patients with early or locally advanced breast cancer. This finding may be a proof of concept that a combined pharmacological intervention directed to these targets could be synergistic.     

The ErbB2 Signaling Network as a Target for Breast Cancer Therapy

Overexpression of the ErbB2/Her2 receptor tyrosine kinase in breast cancers is associated with the most aggressive tumors. Experimental studies have revealed that ErbB2 shows many features of a therapeutic target: ErbB2 is able to confer many of the characteristics of a cancerous cell, including uncontrolled proliferation, resistance to apoptosis and increased motility; ErbB2 overexpression is specific to tumor cells; as a cell surface-associated protein, it is easily accessible to drugs and as a kinase it is amenable to targeted inhibition by small molecules. Recent clinical results demonstrate the efficacy of ErbB2-targeting therapy and promise an expanding use of ErbB2-targeting drugs for breast cancer treatment. However, as only a fraction of patients responds successfully to therapy and risks of recurrence are still high, further investigation is required for an improved understanding of the complex network of signaling pathways underlying ErbB2-driven cancer progression.     

Invasive Breast Cancer: Recognition of Molecular Subtypes

SUMMARY: Molecular profiling has fundamentally changed our understanding of breast cancer in the last 10 years, by creating a new taxonomy of breast cancers based on the expression patterns of so-called 'intrinsic genes'. Hierarchical clustering analyses performed on microarray-based gene expression profiles of breast cancers defined distinct breast cancer subgroups (luminal type A/B, HER2-enriched type, basal-like type). Since the initial landmark study by Perou et al., the concept of intrinsic breast cancer subtypes has been corroborated and expanded by several independent research groups. Further studies revealed individual properties of the intrinsic subgroups regarding the clinical course and the responsiveness to chemotherapy. The new gene expression profile-based taxonomy of breast cancer has been enthusiastically embraced by the scientific community and hailed as a major breakthrough on the way to individually tailored therapies. However, validation of the gene signatures in prospective studies is necessary before accepting these new technologies in daily clinical practice. In this review, the current data regarding the intrinsic subtypes and the associated clinical implications as well as the methodology of molecular profiling and possible use of immunohistochemistry in identifying intrinsic subtypes are discussed.     

Retracted Article: Prognostic Factors in Breast Cancer: The Value of the Nottingham Prognostic Index for Patients Treated in a Single Institution

Purpose The Nottingham Prognostic Index (NPI) is used to predict survival in patients with breast cancer. This index is based on tumor size, lymph node stage, and histological grade and allows the stratification of patients into three different prognostic groups. Our aim was to verify the effect of some prognostic variables on survival and to establish the independent influence of each of these variables by a survival regression analysis. We applied the NPI to the same group of patients to assess its predictive power and reproducibility. Methods We evaluated 311 women with breast cancer treated between January 1993 and December 1998. Results In a multivariate analysis (Cox proportional hazard model), only size, lymph node involvement, and histological grade were independent prognostic factors. The survival curves obtained after applying the NPI were similar to those for the factors with independent prognostic significance derived from our multivariate analysis. Conclusion The NPI allows us to accurately predict prognosis, and we advocate its standardized use.     

Prognostic impact of HER2-low expression in hormone receptor positive early breast cancer

BackgroundRecent data suggest that human epidermal growth factor receptor 2 (HER2)-low breast cancer may represent a distinct entity. We aimed to compare disease characteristics and outcomes between HER2-low and HER2-0 in estrogen receptor (ER) positive, early-stage breast cancer.MethodsA single center retrospective study comprising all women with ER positive, HER2 negative early breast cancer, for whom an Oncotype DX test was performed between 2005 and 2012. Women were grouped to HER2-low (immunohistochemistry +1 or +2 and in situ hybridization not amplified) or HER2-0. Clinico-pathological features and Oncotype recurrence score (RS) were collected. Data on overall-survival (OS), disease-free survival (DFS) and distant disease-free survival (DDFS) were evaluated according to HER2 expression status.Results608 women were included, of which 304 women had HER2-0 and 304 had HER2-low disease. Lobular subtype was significantly more common in HER-0 compared to HER2-low disease (17% vs. 8%, p = 0.005). The prevalence of other clinic-pathological characteristics and long-term prognosis were comparable between both groups. For women with high genomic risk (RS > 25), HER2-low expression was associated with significantly favorable OS (HR = 0.31, 95% CI 0.11–0.78, p = 0.01), DFS (HR = 0.40, 95% CI 0.20–0.82, p = 0.01) and DDFS (HR = 0.26, 95% CI 0.11–0.63, P = 0.002) compared to women with HER2-0. For women with low genomic risk (RS ≤ 25), long-term prognosis was unrelated to HER2 expression.ConclusionThe prognostic impact of HER2-low expression in early-stage luminal disease varies across the genomic risk, with significant favorable outcomes of HER2-low expression compared to HER2-0 in women with high genomic risk.     

ERBB3/HER3 and ERBB2/HER2 Duet in Mammary Development and Breast Cancer

ERBB3/HER3 is one of the four members of the epidermal growth factor receptor (ERBB) family. It is activated by binding to ligands Neuregulin-1 and Neuregulin-2. Since ERBB3 lacks intrinsic kinase activity, signal transduction occurs through formation of heterodimers with EGFR, ERBB2, and ERBB4. ERBB3 is a signaling specialist since it has six binding sites for the p85 SH2 adapter subunit of phosphoinositide 3' kinases. These lipid kinases coordinate regulation of metabolism, cell size, proliferation, survival, and angiogenesis. Not surprisingly, ERBB3 signaling has been linked to cancer etiology and progression. In breast cancer, the partnership of ERBB2 and ERBB3 may be crucial for the aggressive properties of cancers with ERBB2 amplification, and may contribute to pre-existing and acquired resistance to therapy. This partnership creates opportunities for improving efficacy of ERBB-targeted pharmaceuticals, by interfering with coupling of ERBB2 to ERBB3 through dimerization inhibitors, and by use of therapeutic compounds that target AKT-dependent pathways activated through ERBB3. Additional therapeutic opportunities may be identified through better understanding of how ERBBs are regulated and deployed in normal mammary gland processes. Work using mouse models has identified the main processes regulated by each of the four ERBBs, which has practical implications in understanding breast cancer etiology, and eventual development of better prognostic, predictive, and therapeutic tools.     

Clinical Significance of the Epidermal Growth Factor Receptor and HER2 Receptor in Resectable Gastric Cancer

Background: Epidermal growth factor receptor (EGFR or HER1) and its homolog c-erbB-2 (HER2) are membrane receptors. Both EGFR and HER2 genes are overexpressed in a variety of solid human cancers and are related to poor prognosis of the patients. The objective of this work was to evaluate the EGFR and HER2 contents in resectable gastric cancer, their possible relationship with clinicopathologic parameters of tumors, and their prognostic significance.Methods: This was a prospective analysis of 63 patients with resectable gastric carcinomas, with a mean follow-up period of 40.7 months. Membranous EGFR levels were examined by radioligand binding assays, and cytosolic HER2 levels were examined by means of an immunoenzymatic assay.Results: There was a wide variability of EGFR (1–1,239 fmol/mg of protein) and HER2 (7–20,863 NHU/mg of protein) levels in tumors. There was no significant correlation between these levels and patient or tumor characteristics. However, high levels of EGFR and HER2 were significantly associated with a shorter overall survival period (P = .03 and P = .02, respectively).Conclusions: There is a wide variability in membranous EGFR levels and in cytosolic HER2 levels in gastric cancer, which seems to be related to the biological heterogeneity of these tumors. In addition, high tumor EGFR and HER2 levels were associated with an unfavorable outcome in patients with resectable gastric cancer.     

Ancillary Prognostic and Predictive Testing in Breast Cancer: Focus on Discordant,Unusual, and Borderline Results

Ancillary testing in breast cancer has become standard of care to determine what therapies may be most effective for individual patients with breast cancer. Single-marker tests are required on all newly diagnosed and newly metastatic breast cancers. Markers of proliferation are also used, and include both single-marker tests like Ki67 as well as panel-based gene expression tests, which have made more recent contributions to prognostic and predictive testing in breast cancers. This review focuses on pathologist interpretation of these ancillary test results, with a focus on expected versus unexpected results and troubleshooting borderline, unusual, or discordant results.     

Antibody drug conjugates targeting HER2: Clinical development in metastatic breast cancer

The identification of the HER2 alteration as an actionable oncogenic driver in breast cancer has propelled the development of HER-targeting monoclonal antibodies (mAb) such as trastuzumab and pertuzumab, which led to dramatic improvements in survival outcomes. Lately, the great strides made toward developing antibody-conjugation methods have led to the development of a new class of compelling compounds, the antibody-drug conjugates (ADCs) targeting HER2 which have profoundly transformed the treatment landscape of breast cancer. HER2-targeting ADCs, trastuzumab-emtansine and trastuzumab-deruxtecan, have improved the overall survival in the second and third-line settings with manageable adverse events. Other HER2-targeting ADCs using novel technological advances in the antibody, linker and/or payload conception have shown promising activity in preclinical and clinical studies and some of them are now being evaluated in larger clinical trials. Multiple challenges still impede the success of ADCs in breast cancer namely the lack of a comprehensive understanding of resistance mechanisms as well as the mechanisms of action of ADCs in special subgroups of patients such as those with low or ultra-low HER2 expression and patients with brain or leptomeningeal metastases (BM). In this framework, we review the approved indications and ongoing trials for HER2-targeting ADCs, across patient subgroups, including those with BM and discuss the associated potential mechanisms of action and resistance. Last, we provide an overview of the future perspectives involving HER2-targeting ADCs in breast cancer.     

Triple-Negative Breast Cancer: Clinical and Histological Correlations

SUMMARY: Triple-negative breast cancer (TNBC) is characterized by the lack of estrogen and progesterone receptors and the lack of HER2 expression or amplification. Much interest has recently been focused on these triple-negative (TN) subtypes because they may be aggressive and are more likely to recur and metastasize than other subtypes of breast cancer. TNBC accounts for approximately 10-24% of all breast cancer cases, and typically it occurs in younger patients and in patients with BRCA1 mutation. There is a substantial heterogeneity of TNBCs both at the morphological and the molecular level, but there are also common features, such as low tumor grade and accelerated tumor proliferation. Morphologically, TNBC may present as invasive ductal, metaplastic, medullary, apocrine, or other types. Molecularly, they are most frequently associated with a basal phenotype, but there is a distinct subgroup of cancers that are not of basal type and belong to the claudin-low or molecular-apocrine type. The basal phenotype is frequently associated with the loss of BRCA1.     

Investigating the Combination of Trastuzumab and HER2/neu Peptide Vaccines for the Treatment of Breast Cancer

Background Trastuzumab, an anti-HER2/neu monoclonal antibody, is thought to promote HER2/neu receptor internalization and/or turnover. This study was designed to investigate the kinetics of trastuzumab treatment on tumor cells with varying levels of HER2/neu expression and to determine the effect of trastuzumab on HER2/neu-specific cytotoxic T lymphocyte–mediated lysis. Methods Three cell lines with varying levels of HER2/neu expression were incubated with varying doses of trastuzumab at multiple time points. Trastuzumab binding and HER2/neu expression were determined. Peripheral blood mononuclear cells from three HLA-A2⁺ healthy donors and four E75 peptide–vaccinated patients were stimulated with HER2/neu-derived peptides and tested in standard chromium release cytotoxicity assays with HER2/neu⁺ tumor cells pretreated with trastuzumab. Results Treatment of tumor cells with 10 μg/mL of trastuzumab in an overnight incubation resulted in saturation of cell-surface HER2/neu receptors. At higher doses, trastuzumab staining and HER2/neu expression decreased in a time-dependent manner. Pretreatment of tumor cells with trastuzumab resulted in increases in specific cytotoxicity by peptide-stimulated cytotoxic T lymphocytes from HLA-A2⁺ donors over untreated cells by an average of 5.6% and 15.3% (P = .0002) for doses of 10 and 50 μg/mL, respectively. In similar experiments involving peripheral blood mononuclear cells obtained from immunized patients, the average specific cytotoxicity for untreated cells was 34.2% ± 1.3% vs. 40.6% ± 2.5% (P = .035) and 40.7% ± 1.6% (P = .0005) for those treated with 10 and 50 μg/mL, respectively. Conclusions Our data suggest that pretreatment of breast cancer cells with trastuzumab induces turnover of the HER2/neu protein and enhanced killing by HER2/neu peptide–stimulated CTLs. This increased lysis occurs regardless of the degree of HER2/neu expression and seems more pronounced in vaccinated patients. These findings support further investigation into the use of combination immunotherapy with trastuzumab and HER2/neu peptide–based vaccines. The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or reflecting the views of the Department of the Army or the Department of Defense.     

Estrogen Replacement Therapy After Breast Cancer: A 12-Year Follow-Up

Background: In the United States, estrogen replacement therapy ERT is discouraged in breast cancer survivors because of concerns that hormones may reactivate the disease. Because ERT can improve quality of life and decrease morbidity from osteoporosis and cardiovascular disease, however, this policy is increasingly being challenged.Methods: From February to August 1995, 607 breast cancer survivors were interviewed concerning ERT usage. Sixty-four patients indicated they received some form of ERT after their breast cancer diagnosis. Medical records for these patients were analyzed for disease stage, surgical treatment, adjuvant treatment, estrogen and progesterone receptor status, date of initiation of ERT, type of ERT, recurrence, and final outcome. Patients receiving ERT were followed prospectively.Results: Eight patients were excluded because they had used only vaginal cream ERT. The remaining 56 received ERT as conjugated estrogens, an estradiol patch, estropipate, or birth control pills. The median follow-up from diagnosis was 12.8 years range, 4.7–38.9 years. The median time on ERT since diagnosis was 6.4 years range, 1.0–20.9 years; 38% of the patients initiated ERT within 2 years of diagnosis. Estrogen receptors were positive in 28 74% of the 38 cases with available information. Pathological disease stage at time of diagnosis and treatment was 0 in 15 cases 27%, I in 27 48%, and II in 14 25%. Twenty-six patients 47% received adjuvant chemotherapy or hormonal therapy. One local recurrence and one contralateral breast cancer occurred during the follow-up period 13.5 and 9.6 years, respectively, with no regional or distant recurrences, for a 15-year actuarial disease-free survival rate of 92.5%. There were no breast cancer deaths.Conclusions: Use of ERT in a cohort of breast cancer survivors with tumors of generally good prognosis was not associated with increased breast cancer events compared with non-ERT users, even over a long follow-up period.Presented at the 54th Annual Meeting of the Society of Surgical Oncology, Washington, DC, March 15–18, 2001.     

乳腺癌患者血清和肿瘤组织VEGF表达与临床预后的关系

目的探讨乳腺癌患者血清和肿瘤组织中血管内皮细胞生长因子（VEGF）的表达以及与临床预后的关系。方法以44例乳腺癌患者、13例乳腺良性疾病患者和40例正常人为研究对象，分别采用酶联免疫吸附法（ELISA）检测其血清VEGF水平，采用免疫组化LSAB法检测其组织中VEGF、雌激素受体（ER）和原癌基因C-erbB-2蛋白的表达，并分析其与临床预后因素如淋巴结转移情况及临床分期的关系。结果乳腺癌组血清和组织中VEGF表达水平（113．88pg／ml，20723．99）均明显高于乳腺良性疾病组（55．79pg／ml，3594．74），P〈0．001，而乳腺良性疾病组与正常对照组（41．30pg／ml，-）比较差异无统计学意义（P〉0．05）；且血清和组织中VEGF的表达呈正相关（r=0．48，P〈0．01）。有淋巴结转移者血清和组织中VEGF的表达水平（129．60pg／ml，28506．82）明显高于无淋巴结转移者（80．80pg／ml，14656．73），P〈0．01；血清和组织中VEGF的表达与肿瘤的临床分期有关（P〈0．01），但与患者年龄和肿瘤大小无关（P〉0．05）。乳腺癌患者血清和组织中VEGF表达水平与组织中ER表达呈负相关（r=-0．45，P〈0．05），与C-erbB-2表达呈正相关（r=0．48，P〈0．01）。结论乳腺癌患者血清和肿瘤组织中VEGF表达呈正相关，且与其临床预后有关，可作为乳腺癌患者预后判断的重要参考指标之一。     

The Clinical Value of Parasternal Sentinel Node Biopsy in Breast Cancer

Background Lymphoscintigraphy (LS) with sentinel node (SN) biopsy is proposed to provide a feasible method to complete lymphatic staging in breast cancer. The aim of this study was to evaluate the clinical value of parasternal SN biopsy. Methods A total of 984 consecutive patients with clinical stage T1/2N0 invasive breast cancer who underwent LS and SN biopsy were included in the study. A prospectively collected database was used. An intratumoral injection of 50 to 145 MBq of ^99mTc-labeled human albumin colloid (Nanocoll) was used for preoperative LS. Results LS showed the axillary SN in 844 (86%) cases and the parasternal SN in 138 (14%) cases. The median number of visualized parasternal SN was 2 (range, 1–6). Visualization of the parasternal SN was more common in patients with mediocentral tumors (81 of 399; 20%) and in patients with lateral tumors (56 of 585; 10%; P < .0001). Parasternal SNs were visualized more often, in 100 (17%) of 584 patients without axillary metastases compared with 38 (10%) of 400 patients with metastatic axillary nodes (P = .0006). Parasternal SNs were harvested successfully in 121 (88%) patients with visualization of those nodes. Parasternal SN metastases were detected in 18 patients, with a median of 1 metastasis (range, 1–4 metastases). Eight of these 18 patients were axillary node negative. Conclusions Parasternal SN biopsy results in upstaging in 2% of all breast cancer patients who undergo SN biopsy. The clinical value of the procedure seems insignificant, although it may influence the adjuvant treatment regimen in some patients.