Digital validation of breast biomarkers (ER, PR, AR, and HER2) in cytology specimens using three different scanners

Progression in digital pathology has yielded new opportunities for a remote work environment. We evaluated the utility of digital review of breast cancer immunohistochemical prognostic markers (IHC) using whole slide images (WSI) from formalin fixed paraffin embedded (FFPE) cytology cell block specimens (CB) using three different scanners.CB from 20 patients with breast cancer diagnosis and available IHC were included. Glass slides including 20 Hematoxylin and eosin (H&E), 20 Estrogen Receptor (ER), 20 Progesterone Receptor (PR), 16 Androgen Receptor (AR), and 20 Human Epidermal Growth Factor Receptor 2 (HER2) were scanned on 3 different scanners. Four breast pathologists reviewed the WSI and recorded their semi-quantitative scoring for each marker. Kappa concordance was defined as complete agreement between glass/digital pairs. Discordances between microscopic and digital reads were classified as a major when a clinically relevant change was seen. Minor discordances were defined as differences in scoring percentages/staining pattern that would not have resulted in a clinical implication. Scanner precision was tabulated according to the success rate of each scan on all three scanners.In total, we had 228 paired glass/digital IHC reads on all 3 scanners. There was strong concordance kappa ≥0.85 for all pathologists when comparing paired microscopic/digital reads. Strong concordance (kappa ≥0.86) was also seen when comparing reads between scanners.Twenty-three percent of the WSI required rescanning due to barcode detection failures, 14% due to tissue detection failures, and 2% due to focus issues. Scanner 1 had the best average precision of 92%. HER2 IHC had the lowest intra-scanner precision (64%) among all stains.This study is the first to address the utility of WSI in breast cancer IHC in CB and to validate its reporting using 3 different scanners. Digital images are reliable for breast IHC assessment in CB and offer similar reproducibility to microscope reads.

Immunohistochemical expression of FOXP3 in gastric carcinoma; its relation to Ki-67 proliferation marker, HER2/neu expression, and other clinicopathological parameters

Gastric cancer is common cancer in the world. Contradictory results regarding FOXP3 expression in gastric carcinoma were detected and the role of Ki-67 in prognosis is not completely understood. Furthermore, due to increasing use of anti-HER2 drug trastuzumab for gastric cancer, assessment of HER2 expression becomes important. This study tried to assess the FOXP3 expression in gastric carcinoma and to study the relation between its expression and Ki-67 and HER2/neu expression and relation between their expression and other clinicopathological variables. This retrospective study was carried out on 60 gastric adenocarcinoma cases. Tissue microarrays and immunohistochemical staining for FOXP3, Ki-67 and HER2/neu were done and then assessed and scored. HER2/neu expression showed significant relation to Lauren histological type and lymph node status. High Ki-67 index was related significantly to patients' age, lympho-vascular tumor emboli, peri-neural invasion, tumor grade, lymph node status, and cancer stage. There was significant relation between high FOXP3 expression and patients' age, lympho-vascular tumor emboli, peri-neural invasion, tumor grade, lymph node status, and cancer stage. Direct positive significant relationships between HER2/neu, Ki-67, and FOXP3 expression were noticed. Finally, high FOXP3 expression, positive HER2/neu, and high Ki-67 nuclear proliferation index may be an indication of the aggressiveness of gastric carcinoma.

Advances in the treatment of gastric cancer: 2020-2021

PURPOSE OF REVIEW

To review studies from 2020 to 2021 in esophagogastric cancer.

RECENT FINDINGS

After up front D2 gastrectomy for lymph node-positive gastric cancer, 6 months of adjuvant chemotherapy with S-1 and oxaliplatin achieved superior disease-free survival (DFS) compared with 1 year of S-1. The addition of adjuvant radiotherapy, however, added no benefit. After chemoradiotherapy and surgery in esophageal and gastroesophageal junction cancer, in patients with residual disease found at surgery, 1 year of adjuvant nivolumab substantially improved DFS compared with observation alone, leading to regulatory approval for adjuvant nivolumab. In metastatic esophagogastric cancer, the addition of either pembrolizumab or nivolumab to first-line chemotherapy improved response, disease free, and overall survival with the greatest survival benefit dependent on programmed death receptor ligand, programmed death receptor ligand -1 status, leading to regulatory approval for these agents. A preliminary report of a phase 3 trial adding pembrolizumab to first-line chemotherapy with trastuzumab in HER2-positive gastric cancer reported a significant improvement in response, leading to regulatory approval for pembrolizumab. The fibroblast growth factor receptor appears to be a promising new target in gastroesophageal cancer based on phase 2 data for bemarituzumab.

SUMMARY

Optimal adjuvant chemotherapy after D2 resection of node-positive gastric cancer is 6 months of a fluorinated pyrimidine and oxaliplatin, with no benefit for adjuvant radiotherapy. Adjuvant nivolumab after resection of esophageal cancer after chemoradiotherapy improves DFS and is a new care standard. Pembrolizumab added to first-line chemotherapy in both HER2-positive and negative esophagogastric cancer improves outcome and is a new standard of care. Nivolumab added to first-line chemotherapy in HER2-negative gastric cancer improves treatment outcome and is a new care standard.

Impact of HER2 Heterogeneity on Treatment Response of Early-Stage HER2-Positive Breast Cancer: Phase II Neoadjuvant Clinical Trial of T-DM1 Combined with Pertuzumab

Intratumor heterogeneity is postulated to cause therapeutic resistance. To prospectively assess the impact of HER2 (ERBB2) heterogeneity on response to HER2-targeted therapy, we treated 164 patients with centrally confirmed HER2-positive early-stage breast cancer with neoadjuvant trastuzumab emtansine plus pertuzumab. HER2 heterogeneity was assessed on pretreatment biopsies from two locations of each tumor. HER2 heterogeneity, defined as an area with ERBB2 amplification in >5% but <50% of tumor cells, or a HER2-negative area by FISH, was detected in 10% (16/157) of evaluable cases. The pathologic complete response rate was 55% in the nonheterogeneous subgroup and 0% in the heterogeneous group (P < 0.0001, adjusted for hormone receptor status). Single-cell ERBB2 FISH analysis of cellular heterogeneity identified the fraction of ERBB2 nonamplified cells as a driver of therapeutic resistance. These data suggest HER2 heterogeneity is associated with resistance to HER2-targeted therapy and should be considered in efforts to optimize treatment strategies. SIGNIFICANCE: HER2-targeted therapies improve cure rates in HER2-positive breast cancer, suggesting chemotherapy can be avoided in a subset of patients. We show that HER2 heterogeneity, particularly the fraction of ERBB2 nonamplified cancer cells, is a strong predictor of resistance to HER2 therapies and could potentially be used to optimize treatment selection.See related commentary by Okines and Turner, p. 2369.This article is highlighted in the In This Issue feature, p. 2355.

Mechanisms of Therapeutic Antitumor Monoclonal Antibodies

Monoclonal antibodies (mAb) are a major component of cancer therapy. In this review, we summarize the different therapeutic mAbs that have been successfully developed against various tumor-expressed antigens and examine our current understanding of their different mechanisms of antitumor action. These mechanisms of action (MOA) largely center on the stimulation of different innate immune effector processes, which appear to be principally responsible for the efficacy of most unconjugated mAb therapies against cancer. This is evident in studies of mAbs targeting antigens for hematologic cancers, with emerging data also demonstrating the critical nature of innate immune-mediated mechanisms in the efficacy of anti-HER2 mAbs against solid HER2+ cancers. Although HER2-targeted mAbs were originally described as inhibitors of HER2-mediated signaling, multiple studies have since demonstrated these mAbs function largely through their engagement with Fc receptors to activate innate immune effector functions as well as complement activity. Next-generation mAbs are capitalizing on these MOAs through improvements to enhance Fc-activity, although regulation of these mechanisms may vary in different tumor microenvironments. In addition, novel antibody-drug conjugates have emerged as an important means to activate different MOAs. Although many unknowns remain, an improved understanding of these immunologic MOAs will be essential for the future of mAb therapy and cancer immunotherapy.

A Phase I Study of Alpelisib in Combination with Trastuzumab and LJM716 in Patients with PIK3CA-Mutated HER2-Positive Metastatic Breast Cancer

PURPOSE

Activating mutations in PIK3CA promote resistance to HER2-targeted therapy in breast cancer; however, inhibition of PI3K alone leads to escape via feedback upregulation of HER3. Combined inhibition of HER2, HER3, and PI3K overcomes this mechanism preclinically.

PATIENTS AND METHODS

This phase I study investigated the MTD of alpelisib given in combination with trastuzumab and LJM716 (a HER3-targeted antibody) in patients with PIK3CA-mutant HER2-positive (HER2+) metastatic breast cancer (MBC) using the continual reassessment method. Secondary analyses included efficacy and exploratory correlative studies.

RESULTS

Ten patients were treated initially with daily alpelisib (arm A). Grade ≥3 adverse events seen in ≥2 patients included diarrhea (n = 6), hypokalemia (n = 3), abnormal liver enzymes (n = 3), hyperglycemia (n = 2), mucositis (n = 2), and elevated lipase (n = 2). The MTD of alpelisib in arm A was 250 mg daily. This prompted the opening of arm B in which 11 patients received intermittently dosed alpelisib. Grade ≥3 adverse events seen in ≥2 patients included diarrhea (n = 5), hypokalemia (n = 3), and hypomagnesemia (n = 2). The MTD of alpelisib in arm B was 350 mg given 4 days on, 3 days off. Among 17 patients assessed, 1 had a partial response, 14 had stable disease, and 2 had disease progression at best response. Five patients had stable disease for >30 weeks. mRNA profiling of pre- and on-treatment tissue demonstrated PIK3CA target engagement by alpelisib via induction of downstream signaling and feedback pathways.

CONCLUSIONS

Combination treatment with alpelisib, trastuzumab, and LJM716 was limited by gastrointestinal toxicity. Further efforts are warranted to target the PI3K pathway in HER2+ MBC.

Clinical therapeutic effects of trastuzumab in HER2-positive breast cancer patients: A protocol for systematic review and meta-analysis

BACKGROUND

Despite the developments in diagnosis and treatment of HER2-positive metastatic breast cancer, there is a high likelihood in the development of resistance to trastuzumab. In general, HER2-positive patients with deteriorated health face negative clinical outcomes. The present study is conducted to systematically explore the medicinal properties of trastuzumab in HER2-positive breast cancer patients.

METHODS

Randomized controlled trials investigating the clinical properties of including trastuzumab to treat HER2-positive breast cancer cases will be sourced by exploring these online-based databases: MEDLINE, BIOSIS, China National Knowledge Infrastructure (CNKI), Cochrane Library, EMBASE, Central Register of Controlled Trials, and WanFang. Two independent authors will screen the literature, gather data, and assess the quality of selected studies. The significance of the relationship between the medical properties of trastuzumab when incorporated to treat HER2-positive breast cancer cases will be evaluated according to the relative risk, mean differences or standardized mean differences, and 95% confidence interval.

RESULTS

The outcomes from this review shall be issued in a journal that will be reviewed by peers.

CONCLUSION

The conclusions presented in this review will serve as a reference for clinical practitioners and scholars to determine whether trastuzumab is an effective and safety intervention for treating HER2-positive breast cancer patients.

ETHICS AND DISSEMINATION

Since this study is a systematic review of published studies, an ethical approval is not needed.

SYSTEMATIC REVIEW REGISTRATION NUMBER

March 31, 2021.osf.io/wvqkf (https://osf.io/wvqkf/).

Trastuzumab administration during pregnancy: un update

BACKGROUND

Over than one third (28-58%) of pregnancy-associated breast cancer (PABC) cases are characterized by positive epidermal growth factor receptor 2-positive (HER2) expression. Trastuzumab anti-HER2 monoclonal antibody is still the benchmark treatment of HER2-positive breast tumors. However, FDA has categorized Trastuzumab as a category D drug for pregnant patients with breast cancer. This systemic review aims to synthesize all currently available data of trastuzumab administration during pregnancy and provide an updated view of the effect of trastuzumab on fetal and maternal outcome.

METHODS

Eligible articles were identified by a search of MEDLINE bibliographic database and ClinicalTrials.gov for the period up to 01/09/2020; The algorithm consisted of a predefined combination of the words "breast", "cancer", "trastuzumab" and "pregnancy". This study was performed in accordance with the PRISMA guidelines.

RESULTS

A total of 28 eligible studies were identified (30 patients, 32 fetuses). In more than half of cases, trastuzumab was administered in the metastatic setting. The mean duration of trastuzumab administration during gestation was 15.7 weeks (SD: 10.8; median: 17.5; range: 1-32). Oligohydramnios or anhydramnios was the most common (58.1%) adverse event reported in all cases. There was a statistically significant decrease in oligohydramnios/anhydramnios incidence in patients receiving trastuzumab only during the first trimester (P = 0.026, Fisher's exact test). In 43.3% of cases a completely healthy neonate was born. 41.7% of fetuses exposed to trastuzumab during the second and/or third trimester were born completely healthy versus 75.0% of fetuses exposed exclusively in the first trimester. All mothers were alive at a median follow-up of 47.0 months (ranging between 9 and 100 months). Of note, there were three cases (10%) of cardiotoxicity and decreased ejection fraction during pregnancy.

CONCLUSIONS

Overall, treatment with trastuzumab should be postponed until after delivery, otherwise pregnancy should be closely monitored.

2020 consensus guideline for optimal approach to the diagnosis and treatment of HER2-positive breast cancer in Bosnia and Herzegovina

The HERe2Cure project, which involved a group of breast cancer experts, members of multidisciplinary tumor boards from healthcare institutions in Bosnia and Herzegovina, was initiated with the aim of defining an optimal approach to the diagnosis and treatment of HER2 positive breast cancer. After individual multidisciplinary consensus meetings were held in all oncology centers in Bosnia and Herzegovina, a final consensus meeting was held in order to reconcile the final conclusions discussed in individual meetings. Guidelines were adopted by consensus, based on the presentations and suggestions of experts, which were first discussed in a panel discussion and then agreed electronically between all the authors mentioned. The conclusions of the panel discussion represent the consensus of experts in the field of breast cancer diagnosis and treatment in Bosnia and Herzegovina. The objectives of the guidelines include the standardization, harmonization and optimization of the procedures for the diagnosis, treatment and monitoring of patients with HER2-positive breast cancer, all of which should lead to an improvement in the quality of health care of mentioned patients. The initial treatment plan for patients with HER2-positive breast cancer must be made by a multidisciplinary tumor board comprised of at least: a medical oncologist, a pathologist, a radiologist, a surgeon, and a radiation oncologist/radiotherapist.

Tissue Thickness Interferes With the Estimation of the Immunohistochemical Intensity: Introduction of a Control System for Managing Tissue Thickness

CONTEXT AND OBJECTIVE

The conversion of immunohistochemical (IHC) results from 3-dimensional tissue to a 2-dimensional visual image without considering tissue thickness poses a considerable risk of misleading IHC intensities. The present study aimed to clarify whether tissue thickness interferes with the estimation of IHC staining intensity and to introduce a control system to manage it.

DESIGN

We prepared cell lines that are used as controls for human epidermal growth factor receptor 2 (HER2) IHC (MDA-MB-231, MDA-MB-175VII, MDA-MV-453, and SK-BR-3), a polyclonal antibody for HER2, an interferometry to measure the tissue thickness of formalin-fixed paraffin-embedded sections, a microscope with a Halogen or an LED light source, a complementary metal-oxide semiconductor camera in which the output signal can be corrected to γ=1, and a program to estimate color elements (hue, saturation, and luminance). It was examined whether tissue thickness interferes with the experimental scoring systems and practical classification of the routine HER2 scoring system.

RESULTS

A noncellular control was shown to be better than a cellular control for managing tissue thickness. The IHC intensity for HER2 was correlated with tissue thickness (R2=0.8094), even under the less-standardized condition, but this correlation was better under the improved standardized condition using corrected γ=1 (R2=0.9282). Discrepancies in practical HER2 scores were increased in sections with thicknesses <2 and >5 μm. A control system to manage tissue thickness was introduced.

CONCLUSIONS

Tissue thickness interferes with the estimation of the IHC intensity of HER2 in both experimental and practical scoring systems. A control system for managing tissue thickness is essential to increase the benefits of IHC as a standardized assay for clinical applications.

Margetuximab for the treatment of HER2-positive metastatic breast cancer

INTRODUCTION

No specific standard treatment is currently recommended for HER2-positive advanced breast cancer (BC) patients progressing to dual HER2 blockade and to trastuzumab emtansine (TDM-1). However, several novel anti-HER2 agents are emerging and rapidly revolutionizing this setting. Among these, the FC-engineered monoclonal antibody margetuximab has recently demonstrated to slightly improve progression-free survival (PFS) compared with trastuzumab, when combined with chemotherapy for pretreated HER2-positive advanced BC.

AREAS COVERED

The present review article recapitulates the clinical development of margetuximab, critically discussing its implications in the current landscape of BC treatment algorithms.

EXPERT OPINION

The clinical role of Margetuximab can only be interpreted in view of the rapidly evolving treatment landscape for pretreated HER2-positive advanced BC. Indeed, the recently approved anti-HER2 agents tucatinib and trastuzumab deruxtecan currently represent appealing options for the post-TDM1 setting, while margetuximab may have a role after progression to the abovementioned agents, in case of a future approval. Regardless of its clinical uptake, it should be noted that the development of margetuximab has relevantly improved our biological understanding of HER2-positive BC, highlighting the implication of patient's genotype in determining treatment outcomes, as well as the relevance of antibody-dependent cellular cytotoxicity (ADCC) in the context of HER2-blockade.

Her2 promotes early dissemination of breast cancer by suppressing the p38 pathway through Skp2-mediated proteasomal degradation of Tpl2

While mechanisms for metastasis were extensively studied in cancer cells from patients with detectable tumors, pathways underlying metastatic dissemination from early lesions before primary tumors appear are poorly understood. Her2 promotes breast cancer early dissemination by suppressing p38, but how Her2 downregulates p38 is unclear. Here, we demonstrate that in early lesion breast cancer models, Her2 inhibits p38 by inducing Skp2 through Akt-mediated phosphorylation, which promotes ubiquitination and proteasomal degradation of Tpl2, a p38 MAP3K. The early disseminating cells are Her2⁺Skp2^highTpl2^lowp-p38^lowE-cadherin^low in the MMTV-Her2 breast cancer model. In human breast carcinoma, high Skp2 and low Tpl2 expression are associated with the Her2⁺ status; Tpl2 expression positively correlates with that of activated p38; Skp2 expression negatively correlates with that of Tpl2 and activated p38. Moreover, the Her2-Akt-Skp2-Tpl2-p38 axis plays a key role in the disseminating phenotypes in early lesion breast cancer cells; inhibition of Tpl2 enhances early dissemination in vivo. These findings identify the Her2-Akt-Skp2-Tpl2-p38 cascade as a novel mechanism mediating breast cancer early dissemination and a potential target for novel therapies targeting early metastatic dissemination.

Hyperlipoproteinemia (a) is associated with breast cancer in a Han Chinese population

To investigate the relationship between serum lipoprotein (a) (LP(a)) levels and breast cancer as well as the clinicopathologic characteristics of breast cancer in a Han Chinese population.This study included 314 breast cancer patients, 51 patients with benign breast tumors, and 185 healthy control subjects. All study subjects were Han Chinese with similar socio-economic backgrounds, who were local residents of Zhoushan, Zhejiang, China or who had lived in Zhoushan for a long period of time. Serum concentrations of LP(a) were determined using a latex-enhanced immunoturbidimetric assay. Clinicopathological characteristics of patients were retrieved from medical records, which included the histopathological type, grade, stage, and molecular subtype of the disease, the expression of estrogen receptor (ER), progesterone receptor (PR), HER2, and Ki67, and the level of reproductive hormones. Correlations between 2 groups were evaluated using the Spearman correlation analysis. Associations among ≥3 groups were interpreted using the Kruskal-Wallis H test or the logistic regression test.Elevated serum LP(a) levels were detected in breast cancer patients compared with healthy control subjects, but no significant differences in LP(a) were detected between breast cancer and benign tumor or between benign tumor and healthy control. In breast cancer patients, serum LP(a) levels were inversely associated with HER2 expression, but they were not significantly correlated with any other clinicopathologic characteristics of breast cancer evaluated in this study.Elevated serum LP(a) levels were associated with breast cancer in a Han Chinese population.

What Is the Real Impact of Estrogen Receptor Status on the Prognosis and Treatment of HER2-Positive Early Breast Cancer?

HER2+ early breast cancer is a heterogeneous disease, comprising all the intrinsic breast cancer subtypes. The only biomarker available nowadays for anti-HER2 treatment selection is HER2 status itself, but estrogen receptor (ER) status is emerging as a robust predictive marker within HER2+ disease. In this Perspective, we discuss the biological and clinical differences between patients with HER2+/ER-positive (ER+) disease versus those with HER2+/ER-negative (ER-neg) tumors, namely, short-term and long-term (>5 years after diagnosis) prognosis, response to neoadjuvant treatment and benefit from adjuvant anti-HER2-targeted therapies. We also address other possible biomarkers to be used for patient selection in future clinical trials, such as gene signatures, PAM50 subtypes, tumor-infiltrating lymphocytes, PIK3CA mutations, and changes in Ki67 score during treatment and discuss their limitations. Finally, we suggest new clinical trial designs that can have an impact on clinical practice, aiming to test treatment deescalation separately for patients with HER2+/ER+ and HER2+/ER-neg tumors. We also propose an integrated classification of HER2+ disease, comprising DNA, RNA, protein expression, and microenvironment characteristics, in order to identify those tumors that are truly "HER2-addicted" and may benefit the most from anti-HER2 treatment.

Enhancing Antitumor Efficacy of Nucleoside Analog 5-Fluorodeoxyuridine on HER2-Overexpressing Breast Cancer by Affibody-Engineered DNA Nanoparticle

BACKGROUND

Chemotherapy, as an adjuvant treatment strategy for HER2-positive breast cancer, can effectively improve clinical symptoms and overcome the drug resistance of therapeutic monoclonal antibodies. Nucleoside analogues are a class of traditional chemotherapeutic drugs that are widely applied in adjuvant therapy. However, there are many critical issues that limit their clinical efficiency, including poor selectivity and stability, severe side effects and suboptimal therapeutic efficacy. Hence, this work aims to develop a new DNA nanocarrier for targeted drug delivery to solve the above problems.

METHODS

Four 41-mer DNA strands were synthesized and 10 FUdR molecules were attached to 5' end of each DNA strand by DNA solid-phase synthesis. An affibody molecule was connected to the end of polymeric FUdR through a linker in one of the four strands. The affibody-FUdR-tetrahedral DNA nanostructures (affi-F/TDNs) were self-assembled through four DNA strands, in which one vertex was connected to an affibody at the end of a polymeric FUdR tail and three vertices were only polymeric FUdR tails. In vitro cellular uptake of affi-F/TDNs was examined visually with confocal fluorescence microscopy and flow cytometry, and the cytotoxicity of affi-F/TDNs against cancer cells was investigated with MTT assay. Cell apoptosis was detected by Annexin V-FITC/PI double staining method. Using NOD/SCID (Mus Musculus) mice model, the targeted killing efficacy of affi-F/TDNs was also evaluated.

RESULTS

The drug-loading of FUdR in affi-TDNs was 19.6% in mole ratio. The in vitro results showed that affi-F/TDNs had high selectivity and inhibition (81.2%) for breast cancer BT474 cells overexpressing HER2 and low toxicity in MCF-7 cells with low HER2 expression. During the in vivo application, affi-F/TDNs displayed good stability in the blood circulation, achieved specific accumulation in tumor region and the best antitumor efficacy (inhibition ratio of 58.1%), and showed excellent biocompatibility.

CONCLUSIONS

The affibody-DNA tetrahedrons, as a simple and effective active targeting delivery nanocarrier, provided a new avenue for the transport of nucleoside antitumor drugs.

Long-term complete response to intrathecal trastuzumab in a patient with leptomeningeal carcinomatosis due to her2- overexpressing breast cancer: Case report

INTRODUCTION

Leptomeningeal dissemination due to HER2-overexpressing breast cancer is a rare and hard to treat complication with short-term dismal prognosis.

PATIENT CONCERNS

A 34-year-old female previously treated because of HER2+ breast cancer is admitted to the Neurology Department in December 2016 due to sensory-motor neurological semiology.

DIAGNOSIS

A wide set of diagnostic tests is performed and finally cytologic findings after repeated CSF confirm leptomeningeal infiltration by breast carcinoma (panCK+, GATA3+).

INTERVENTIONS

Weekly intrathecal triple therapy with methotrexate, cytarabine and hydrocortisone plus trastuzumab is carried out during 4 months.

OUTCOMES

Clinical and pathological response that lasts more than 24 months.

CONCLUSION

Leptomeningeal carcinomatosis is an oncological situation where conventional therapies have limited activity. In HER2+ advanced breast cancer patients, intrathecal therapy with anti-HER2 therapy (trastuzumab) is feasible and may reach long-term disease control, especially in cases of low-tumor burden.

An evaluation of the safety of continuing trastuzumab despite overt left ventricular dysfunction

Background

The major limitation in the use of trastuzumab therapy is cardiotoxicity. We evaluated the safety of a strategy of continuing trastuzumab in patients with breast cancer despite mild, asymptomatic left ventricular impairment.

Methods

Charts of consecutive patients referred to a cardio-oncology clinic from January 2015 to March 2017 for decline in left ventricular ejection fraction (lvef), defined as a fall of 10 percentage points or more, or a value of less than 50% during trastuzumab therapy, were reviewed. The primary outcome of interest was change in lvef, measured before and during trastuzumab exposure and up to 3 times after initiation of cardiac medications during a median of 9 months.

Results

All 18 patients referred for decline in lvef chose to remain on trastuzumab and were included. All patients were treated with angiotensin converting-enzyme inhibitors or beta-blockers, or both. After initiation of cardiac medications, lvef increased over time by 4.6 percentage points (95% confidence interval: 1.9 percentage points to 7.4 percentage points), approaching baseline values. Of the 18 patients, 17 (94%) were asymptomatic at all future visits. No deaths occurred in the group.

Conclusions

Many patients with mildly reduced lvef and minimal heart failure symptoms might be able to continue trastuzumab without further decline in lvef, adverse cardiac events, or death when treated under the supervision of a cardiologist with close follow-up.

A chemical conjugate between HER2-targeting antibody fragment and Pseudomonas exotoxin A fragment demonstrates cytotoxic effects on HER2-expressing breast cancer cells

Conventionally, immunotoxins have been produced as a single polypeptide from fused genes of an antibody fragment and a toxin. In this study, we adopted a unique approach of chemical conjugation of a toxin protein and an antibody fragment. The two genes were separately expressed in Escherichia coli and purified to high levels of purity. The two purified proteins were conjugated using a chemical linker. The advantage of this approach is its ability to overcome the problem of low recombinant immunotoxin production observed in some immunotoxins. Another advantage is that various combinations of immunotoxins can be prepared with fewer efforts, because the chemical conjugation of components is relatively simpler than the processes involved in cloning, expression, and purification of multiple immunotoxins. As a proof of concept, the scFv of trastuzumab and the PE24 fragment of Pseudomonas exotoxin A were separately produced using E. coli and then chemically crosslinked. The new immunotoxin was tested on four breast cancer cell lines variably expressing HER2. The chemically crosslinked immunotoxin exhibited cytotoxicity in proportion to the expression level of HER2. In conclusion, the present study revealed an alternative method of generating an immunotoxin that could effectively reduce the viability of HER2-expressing breast cancer cells. These results suggest the effectiveness of this method of immunotoxin crosslinking as a suitable alternative for producing immunotoxins. [BMB Reports 2019; 52(8): 496-501].

Neutralization of BCL-2/XL Enhances the Cytotoxicity of T-DM1 In Vivo

One of the most recent advances in the treatment of HER2+ breast cancer is the development of the antibody-drug conjugate, T-DM1. T-DM1 has proven clinical benefits for patients with advanced and/or metastatic breast cancer who have progressed on prior HER2-targeted therapies. However, T-DM1 resistance ultimately occurs and represents a major obstacle in the effective treatment of this disease. Because anti-apoptotic BCL-2 family proteins can affect the threshold for induction of apoptosis and thus limit the effectiveness of the chemotherapeutic payload, we examined whether inhibition of BCL-2/XL would enhance the efficacy of T-DM1 in five HER2-expressing patient-derived breast cancer xenograft models. Inhibition of BCL-2/XL via navitoclax/ABT-263 significantly enhanced the cytotoxicity of T-DM1 in two of three models derived from advanced and treatment-exposed metastatic breast tumors. No additive effects of combined treatment were observed in the third metastatic tumor model, which was highly sensitive to T-DM1, as well as a primary treatment-exposed tumor, which was refractory to T-DM1. A fifth model, derived from a treatment naïve primary breast tumor, was sensitive to T-DM1 but markedly benefited from combination treatment. Notably, both PDXs that were highly responsive to the combination therapy expressed low HER2 protein levels and lacked ERBB2 amplification, suggesting that BCL-2/XL inhibition can enhance sensitivity of tumors with low HER2 expression. Toxicities associated with combined treatments were significantly ameliorated with intermittent ABT-263 dosing. Taken together, these studies provide evidence that T-DM1 cytotoxicity could be significantly enhanced via BCL-2/XL blockade and support clinical investigation of this combination beyond ERBB2-amplified and/or HER2-overexpressed tumors.

Endogenous CD4+ T Cells Recognize Neoantigens in Lung Cancer Patients, Including Recurrent Oncogenic KRAS and ERBB2 (Her2) Driver Mutations

T cells specific for neoantigens encoded by mutated genes in cancers are increasingly recognized as mediators of tumor destruction after immune-checkpoint inhibitor therapy or adoptive cell transfer. Much of the focus has been on identifying epitopes presented to CD8+ T cells by class I MHC. However, CD4+ class II MHC-restricted T cells have been shown to have an important role in antitumor immunity. Unfortunately, the vast majority of neoantigens recognized by CD8+ or CD4+ T cells in cancer patients result from random mutations and are patient-specific. Here, we screened the blood of 5 non-small cell lung cancer (NSCLC) patients for T-cell responses to candidate mutation-encoded neoepitopes. T-cell responses were detected to 8.8% of screened antigens, with 1 to 7 antigens identified per patient. A majority of responses were to random, patient-specific mutations. However, CD4+ T cells that recognized the recurrent KRAS G12V and the ERBB2 (Her2) internal tandem duplication (ITD) oncogenic driver mutations, but not the corresponding wild-type sequences, were identified in two patients. Two different T-cell receptors (TCR) specific for KRAS G12V and one T-cell receptor specific for Her2-ITD were isolated and conferred antigen specificity when transfected into T cells. Deep sequencing identified the Her2-ITD-specific TCR in the tumor but not nonadjacent lung. Our results showed that CD4+ T-cell responses to neoantigens, including recurrent driver mutations, can be derived from the blood of NSCLC patients. These data support the use of adoptive transfer or vaccination to augment CD4+ neoantigen-specific T cells and elucidate their role in human antitumor immunity.

Change of HER2 status during disease recurrence predicts good prognosis for primary squamous cell carcinoma of the breast: A case report

RATIONALE

Primary squamous cell carcinoma (PSCC) of the breast is one of the least common types of breast cancer. Adjuvant treatment for PSCC remains an unresolved issue.

PATIENT CONCERNS

We reported a case of a 48-year-old postmenopausal female patients with a 2 × 2.5 cm lump presented with no symptoms.

DIAGNOSES

This patient was diagnosed as PSCC of the breast. The original tumor and first recurrence exhibited triple negative phenotype, whereas the second recurrence was HER2-positive.

INTERVENTIONS

A tumorectomy with latissimus dorsi flap reconstruction for the second recurrence was performed followed by targeted therapy with trastuzumab.

OUTCOMES

The patient had a complete remission, which was sustained over the 25 months of follow-up after the tumorectomy.

LESSONS

This is the first reported case in literature of a breast PSCC patient with switched immunohistochemical phenotypes during disease recurrence. Surgical resection with flap reconstruction and targeted therapy successfully treated the recurrence.

Anti-Yo antibody-mediated paraneoplastic cerebellar degeneration associated with cognitive affective syndrome in a patient with breast cancer: a case report and literature review

Breast cancer is the most common cancer in women, with 15%-25% of those tumours overexpressing the human epidermal growth factor receptor 2 (her2), which is associated with more aggressive disease. On rare occasions, patients present with a paraneoplastic syndrome months to years before their cancer diagnosis. Paraneoplastic cerebellar degeneration (pcd) is associated with fewer than 1% of cancers and is strongly associated with breast and gynecologic malignancies. Anti-Yo antibody is the antibody most frequently identified with the syndrome, and it is associated with a very poor prognosis. Recent studies have implicated a relationship between overexpression of her2 and anti-Yo-mediated pcd. Current pcd treatments include tumour removal, chemotherapy, targeted therapy, and immune-suppressive treatments. Outcomes of pcd are typically poor, and no guidelines for treatment currently exist. Early recognition followed by rapid initiation of treatment remains the cornerstone of therapy. Here, we present a case of anti-Yo-antibody pcd secondary to estrogen and progesterone receptor-negative, her2-positive breast cancer. Despite treatment with mastectomy, chemotherapy, and her2-targeted therapy, no significant neurologic improvement was achieved, and cerebellar cognitive affective syndrome subsequently developed.

Myelophthisic Anemia in a Patient with Lobular Breast Carcinoma Metastasized to the Bone Marrow

Breast tumors have a predilection for metastasizing to the bone leading to cells being displaced by the cancer cells subsequently producing immature leukocytes and erythrocytes in the peripheral blood. We present a case of a 57-year-old female who was found to have myelophthisic anemia secondary to stage four lobular breast carcinoma metastasized to the bone marrow after being misdiagnosed as having thrombotic thrombocytopenia purpura. Diagnosis of myelophthisic anemia requires a thorough workup and treatment is based upon secondary management of the malignancy.

Phase I study of TrasGEX, a glyco-optimised anti-HER2 monoclonal antibody, in patients with HER2-positive solid tumours

Purpose

TrasGEX is a second-generation monoclonal antibody of trastuzumab, glyco-optimised to enhance antibody-dependent cellular cytotoxicity while fully retaining trastuzumab’s antigen-binding properties to human epidermal growth factor receptor 2 (HER2). A phase I dose-escalation study was conducted to establish the optimal TrasGEX dose and regimen for phase II studies and to define the safety, pharmacokinetics (PK) and preliminary antitumour activity of TrasGEX.

Patients and methods

A total of 37 patients with advanced HER2-positive carcinomas and progressive disease received TrasGEX intravenously every 3 weeks until disease progression in doses of 12–720 mg in a three-plus-three dose escalation design, including an expansion cohort at the highest dose.

Results

No dose limiting toxicity was observed, and no maximum tolerated dose was reached. Drug-related adverse events were mainly infusion-related reactions occurring during the first infusion in 51% of patients; all but two were mild-to-moderate. Compared with trastuzumab, the PK parameters were dose dependent, with a mean terminal half-life (t_1/2) of 263±99 hours for the 720 mg dose. Clinical benefit in 15 out of 30 (50%) evaluable patients included one ongoing complete response, two partial remissions lasting 16 and 77 weeks and disease stabilisation (SD) in 12 patients lasting a median (range) of 17 (7–26) weeks; three of them had SD of 24, 25 and 26 weeks, respectively.

Conclusion

TrasGEX was safe, well-tolerated and showed antitumour activity in 50% of evaluable patients, all with progressive disease at study entry. Infusions at an interval of 2–3 weeks should achieve clinically relevant trough levels for future studies (NCT01409343).

Comparison of Molecular Subtypes of Carcinoma of the Breast in Two Different Age Groups: A Single Institution Experience

Background

Hormonal analysis and molecular subtyping are used as an important predictive and prognostic factors in women with carcinoma of the breast. The aim of this study was to analyze and compare the hormonal (estrogen receptor (ER) and progesterone receptor (PR)) and human epidermal growth factor (HER2) status among women with carcinoma breast belonging to two different age groups and classify them in molecular subtypes (luminal A, luminal B, triple negative, and HER2).

Materials and Methods

This was an analytical cross-sectional study performed at a tertiary care center in Northern India. Breast carcinoma cases treated over a period of two years were stratified into two groups (≤ 40 years: younger group, n = 27 and > 40 years: older group, n = 33). Their hormonal (ER, PR) and HER2 status were studied using immunohistochemistry (IHC) and classified according to the molecular classification of the breast carcinoma.

Results

A total of 60 cases of breast carcinoma were treated for hormonal and HER2 status during our study period and were classified into four subtypes. In the younger group (n = 27), luminal A (n = 16, 59.2%) was the most common molecular subtype, followed by triple negative (n = 6, 22.2%), HER2 (n = 4, 14.8%), and luminal B (n = 1, 3.7%). Similarly, in the older group luminal A (n = 20, 60.6%) ranked first, followed by triple negative (n = 10, 30.3%), HER2 (n = 2, 6.0%), and luminal B (n = 1, 3.0%).

Conclusion

Carcinoma of the breast in young women shows variation in the prevalence of molecular subtypes in different regions of the world. The results of our study are in accordance with the Asian literature, showing no significant difference in molecular subtyping of carcinoma breast in younger versus older women. More molecular research is needed to clearly understand the pathophysiology associated with carcinoma of the breast in young women.