Update Breast Cancer 2019 Part 5 - Diagnostic and Therapeutic Challenges of New, Personalised Therapies in Patients with Advanced Breast Cancer

A Review of the Advancements in Targeted Therapies for Breast Cancer

Breast cancer, the second-most common and lethal disease in women, poses a severe danger to global health. Breast cancer rates continue to climb despite advances in medical technology. Predictions indicate that by 2040, there will be more than three million new cases yearly. Targeted medicines have experienced a profound transformation in treating breast cancer, allowing for individualized strategies that lessen side effects and improve patient outcomes. This thorough analysis gives a rigorous investigation of current developments in breast cancer-targeted treatments. It carefully examines several subtypes, including hormone receptor-positive (HR+), HER2-positive (HER2+), and triple-negative breast cancer (TNBC), recognizing the illness' fundamental variety. It offers specialized treatment plans catered to each subtype's particular traits. The review also examines how precise genetic abnormalities like BRCA1/2 and PIK3CA mutations and molecular profiling facilitate therapy selection. Monoclonal antibodies and small molecule inhibitors are some of the targeted medicines examined in the study. It explains how each of these treatments works and supports its findings with data from clinical trials. It also considers potential new medications and addresses persistent problems, such as resistance mechanisms, chances for combining therapies, and cutting-edge patient classification techniques. This study seeks to give healthcare professionals, researchers, and patients a thorough overview of the recent advancements in breast cancer-targeted therapy by drawing on the opinions of top authorities in the area. The coordinated effort aims to create customized, efficient therapies, eventually bolstering the battle against this powerful illness.

Variable Expression of the Disialoganglioside GD2 in Breast Cancer Molecular Subtypes

Simple Summary

GD2 is an antigen that is tumor-specific and can be used as a target for specific immunotherapies. Since the knowledge about GD2 in breast cancer is limited, we analyzed the frequency of GD2 expression in breast cancer using two different staining methods and the impact of GD2 expression on the survival of breast cancer patients. GD2 expression was found in more than 50% of breast cancer cases, with the highest frequency in hormone receptor-positive tumors. GD2 expression was not significantly associated with patient outcome. Unlike previous studies with smaller sample sizes that lacked correlation with clinical data, this study includes a larger cohort and associations with survival data and shows that GD2 is expressed on human breast cancer cells, providing a potential target for immunotherapies (e.g., anti-GD2 antibodies or GD2 CAR T cells), that are currently undergoing clinical testing.

Abstract

The disialoganglioside GD2 is a tumor-associated antigen that may allow for the application of targeted immunotherapies (anti-GD2 antibodies, GD2 CAR T cells) in patients with neuroblastoma and other solid tumors. We retrospectively investigated GD2 expression in a breast cancer cohort, using immunohistochemistry (IHC) and immunofluorescence (IF) on tissue microarrays (TMAs), and its impact on survival. GD2 expression on IHC (n = 568) and IF (n = 503) was investigated in relation to subtypes and patient outcome. Overall, 50.2% of the 568 IHC-assessed samples and 69.8% of the 503 IF-assessed samples were GD2-positive. The highest proportion of GD2-positive tumors was observed in luminal tumors. Significantly fewer GD2-positive cases were detected in triple-negative breast cancer (TNBC) compared with other subtypes. The proportion of GD2-expressing tumors were significantly lower in HER2-positive breast cancer in comparison with luminal tumors on IF staining (but not IHC). GD2 expression of IHC or IF was not significantly associated with disease-free or overall survival, in either the overall cohort or in individual subtypes. However, GD2 expression can be seen in more than 50% of breast cancer cases, with the highest frequency in hormone receptor-positive tumors. With this high expression frequency, patients with GD2-positive advanced breast cancer of all subtypes may benefit from GD2-targeting immunotherapies, which are currently subject to clinical testing.

Update Breast Cancer 2020 Part 5 - Moving Therapies From Advanced to Early Breast Cancer Patients

In recent years, significant progress has been made in new therapeutic approaches to breast cancer, particularly in patients with HER2-positive and HER2-negative/hormone receptor-positive (HR+) breast cancer. In the case of HER2-positive tumours, these approaches have included, in particular, treatment with pertuzumab, T-DM1, neratinib and, soon, also tucatinib and trastuzumab deruxtecan (neither of which has yet been authorised in Europe). In patients with HER2-/HR+ breast cancer, CDK4/6 inhibitors and the PIK3CA inhibitor alpelisib are of particular importance. Further novel therapies, such as Akt kinase inhibitors and oral SERDs (selective estrogen receptor down regulators), are already being investigated in ongoing clinical trials. These therapeutic agents are not only being introduced into curative, (neo-)adjuvant therapeutic settings for HER2-positive tumours; a first favourable study on abemaciclib as an adjuvant therapy has now also been published. In patients with triple-negative breast cancer, after many years of negative study results with the Trop-2 antibody drug conjugate (ADC) sacituzumab govitecan, a randomised study has been published that may represent a significant therapeutic advance. This review describes the latest developments in breast cancer subsequent to the ESMO Congress 2020.

Update Breast Cancer 2020 Part 3 - Early Breast Cancer

The treatment of patients with early breast cancer has always been characterised by escalation by new therapies and de-escalation through identification of better treatment regimens or introduction of better tools to estimate prognosis. Efforts in some of these areas in the last few years have led to solid data. The results of the large studies of de-escalation through use of multi-gene tests are available, as are the results of some studies that investigated the new anti-HER2 substances T-DM1 and pertuzumab in the early treatment situation. Several large-scale studies examining the role of CDK4/6 inhibitors will soon be concluded so innovations can be anticipated in this area also. This review article will summarise and classify the results of the latest publications.

Update Breast Cancer 2020 Part 4 - Advanced Breast Cancer

Substances with good effectiveness that intervene in specific signalling pathways have been used increasingly in recent years in the treatment of patients with advanced breast cancer, and new therapies and approaches have now been added, which actually relate to quite specific changes, such as the treatment of patients with HR+/HER2 tumours with a PIK3CA mutation. The treatment of patients with a BRCA1 or BRCA2 mutation has also been improved by the introduction of PARP inhibitors. Attempts are now being made increasingly to extend treatment indications based on molecular patterns, to identify other patients who could benefit from a treatment and to integrate the newly established treatment methods in existing therapy sequences. This review articles summarises the latest information in this connection.

Progression-Free Survival and Overall Survival in Patients with Advanced HER2-Positive Breast Cancer Treated with Trastuzumab Emtansine (T-DM1) after Previous Treatment with Pertuzumab

Simple Summary

Data about the efficacy of trastuzumab emtansine (T-DM1) following pertuzumab treatment is limited due to the simultaneous development of the two drugs. Thus, the aim of this study was to investigate the efficacy of T-DM1 after previous treatment with pertuzumab in a large, real-world group of patients. We showed that the progression-free survival (PFS) in patients treated with T-DM1 after pertuzumab was 3.5 months. T-DM1 was mainly administered second-line after pertuzumab. The PFS in higher therapy lines appears to be shorter than in second-line ones. In summary, this study provides evidence that T-DM1 has clinically reasonable activity after prior pertuzumab treatment, with a median PFS period of approximately 3–4 months. It appears to be recommendable to administer T-DM1 in earlier therapeutic lines.

Abstract

The approval of trastuzumab emtansine (T-DM1) was conducted without pertuzumab as previous therapy. Efficacy data on T-DM1 following pertuzumab treatment are therefore limited. This study explores this issue in a real-world setting. Within the prospective PRAEGNANT (Prospective Academic Translational Research Network for the Optimization of the Oncological Health Care Quality in the Advanced Setting) metastatic breast cancer registry (NCT02338167), patients in all therapy lines receiving any kind of treatment were eligible for inclusion. This report describes patient characteristics and progression-free survival (PFS) in human epidermal growth factor receptor 2 (HER2)-positive patients receiving T-DM1 after pertuzumab treatment. Seventy-six patients were identified, 39 of whom received T-DM1 as second-line therapy, 25 as third-line, and 12 as fourth-line therapy or higher. Pertuzumab was mostly administered as a first-line treatment (n = 61; 80.3%). The median PFS in all patients was 3.5 months (95% CI: 2.8–7.8); in second-line treatment, 7.7 months (95% CI: 2.8–11.0); in third-line, 3.4 months (95% CI: 2.3–not reached (NR)); and in fourth-line therapy or higher, 2.7 months (95% CI: 1.2–NR). T-DM1 was mainly administered second-line after pertuzumab, but also in more heavily pretreated patients. The PFS in higher therapy lines appears to be shorter than in second-line.

Analysis of Oncological Second Opinions in a Certified University Breast and Gynecological Cancer Center Regarding Consensus between the First and Second Opinion and Conformity with the Guidelines

Introduction

Oncological second opinions are becoming increasingly important in the era of complex treatments and established certified cancer centers. Oncological guidelines with the highest levels of evidence are available, but these can only be effective to the extent that they are implemented. Therefore, we analyzed the effects of second opinions with regard to their agreement with first opinions and conformity with guidelines.

Methods

In 164 patients with a diagnosis of breast cancer or gynecological malignancy who requested a second opinion, the first and second opinions, established at the interdisciplinary tumor conference, and conformity with the guidelines were evaluated.

Results

The first opinion was not in agreement with the guidelines in 34.8% (15.2% diagnosis, 12.8% surgical therapy, 13.4% systemic therapy, and 5.5% radiotherapy), and the recommendations were optimized in the second opinion in 56.7% (28.7% diagnosis, 15.9% surgical therapy, 30.5% systemic therapy, and 8.5% radiotherapy).

Conclusions

Oncological second opinions showed significant effects and one-third of first opinions were not in conformity with the guidelines. In a significant proportion of cases, the existing treatment plan was changed or supplemented to allow modern and individualized treatment approaches.

Analysis of Oncological Second Opinions in a Certified University Breast and Gynecological Cancer Center in Relation to Complementary and Alternative Medicine

INTRODUCTION

Oncological second opinions are becoming increasingly important given more complex treatment strategies, simultaneously more patients use complementary and alternative medicine (CAM), and many comprehensive cancer centers initiate integrative medicine programs. The present study focuses on analyzing the effects of a second opinion in relation to attitudes toward CAM.

METHODS

In this prospective study patients (n = 97) with a diagnosis of breast cancer or gynecological malignancies who had requested a second opinion received a questionnaire before and after the second opinion concerning their attitudes toward CAM.

RESULTS

The majority of patients had breast cancer (72.2%, n = 70). Only 6.2% (n = 6) stated that they had been informed about CAM by the doctors who treated them first, 21.6% (n = 21) had received information about it when seeking the second opinion. After the first opinion, 42.3% (n = 41) wanted to try CAM, the same proportion trusted orthodox medicine alone. After the second opinion, 24 patients (24.7%) wanted to try CAM, while 38.1% (n = 37) relied exclusively on orthodox medicine. There was a significant correlation between an increased patients' need for information and interest in CAM (p = 0.02).

CONCLUSIONS

Today, aspects of CAM still are very often no part of oncological first and second opinions. This might hence lead to discouraging patients to try out CAM and therefore integrative medicine programs in comprehensive cancer centers might be problem-solving.

Analysis of motives and patient satisfaction in oncological second opinions provided by a certified university breast and gynecological cancer center

Purpose

Second opinions in oncology are becoming increasingly important in an era of more complex treatments and a growing demand for information by patients. Therefore, we analyzed their effects and influencing factors like patients’ motives, subjective extent of information and satisfaction with communications.

Methods

This prospective study evaluated second opinions for patients with breast cancer or gynecological malignancy. The patients received a questionnaire before and two months after, which inquired expectations, reasons, and satisfaction with the second opinion and the attending physicians.

Results

A total of 164 patients were included and the majority had breast cancer (75.0%). Receiving the second opinion made 89.7% feel better informed, their need for information decreased (from 75.3% to 39.2%, P < 0.0001), and satisfaction with doctor–patient communications increased (from 61.9 to 91.8%, P = 0.0002). There were various reasons for requesting a second opinion, e.g., the extremely stressful situation of a cancer diagnosis, hope for change in the treatment recommendation or dissatisfaction with the initial physicians.

Conclusions

Second opinions can lead to significantly greater patient satisfaction, meeting the need for information and leading to better management of patients in the extremely stressful situation of a cancer diagnosis. Doctor–patient communications play a key role.

Electronic supplementary material

The online version of this article (10.1007/s00404-020-05525-2) contains supplementary material, which is available to authorized users.

Update Breast Cancer 2020 Part 1 - Early Breast Cancer: Consolidation of Knowledge About Known Therapies

This review is intended to present the latest developments in the prevention and treatment of early breast cancer. The risk of breast cancer can be increasingly better characterised with large epidemiological studies on genetic and non-genetic risk factors. Through new analyses, the evidence for high-penetrance genes as well as for low-penetrance genes was able to be improved. New data on denosumab and atezolizumab are available in the neoadjuvant situation as is a pooled appraisal of numerous studies on capecitabine in the curative situation. There is also an update to the overall survival data of pertuzumab in the adjuvant situation with a longer follow-up observation period. Finally, digital medicine is steadily finding its way into science. A recently conducted study on automated breast cancer detection using artificial intelligence establishes the basis for a future review in clinical studies.