Combined tamoxifen and luteinizing hormone-releasing hormone (LHRH) agonist versus LHRH agonist alone in premenopausal advanced breast cancer: a meta-analysis of four randomized trials

Management of cancer treatment-induced bone loss (CTIBL) in patients with breast cancer or prostate cancer

Breast cancer and prostate cancer are sex hormone-dependent cancers, and estrogen or androgen suppression therapy is the standard treatment. Cancer treatment-induced bone loss (CTIBL): bone loss and osteoporosis have become important side effects of these therapies. To summarize the current evidences, (1) Endocrine therapy for breast cancer and prostate cancer is associated with a significant decrease in bone mineral density. (2) Aromatase inhibitors (AI) for breast cancer are associated with a significant increase in fractures, and androgen deprivation therapy (ADT) for prostate cancer is likely to be associated with an increase in fractures. (3) Administration of bisphosphonates and denosumab increases bone mass in patients undergoing endocrine therapy for breast cancer. Administration of bisphosphonates, denosumab, and SERMs increased bone mass in patients undergoing ADT therapy for prostate cancer. (4) Bisphosphonates and denosumab reduce fracture risk in patients on AI for breast cancer, and toremifene and denosumab in patients on ADT for prostate cancer.

Clinicopathological characteristics and treatment outcomes of luminal B1 breast cancer in Taiwan

BACKGROUND

Hormone receptor-positive, human epidermal growth factor receptor II (HER2)-negative luminal B1 breast cancer is associated with a higher risk of disease relapse than luminal A breast cancer. Therefore, we assessed and compared the distant metastasis pattern and clinical outcomes associated with luminal B1 and luminal A breast cancer in an Asian population.

METHODS

In this observational study, we assessed patients with estrogen receptor-positive, HER2-negative breast cancer who underwent surgery from 2009 to 2016. Patients were classified into luminal A or luminal B1 subsets via immunohistochemical analysis. Disease-free survival, post-metastasis survival, and overall survival were estimated; time to disease relapse and patterns of distant metastasis were compared. Risk of relapse and mortality were assessed using Cox proportional hazards model.

RESULTS

Patients with luminal B1 breast cancer (n = 677) were significantly younger and had larger tumors and a higher degree of affected axillary lymph nodes, lymphovascular invasion, and tumor necrosis than those with luminal A breast cancer (n = 630). Higher rates of local recurrence and distant metastasis were observed for luminal B1 (both p < 0.05); however, no difference was observed in the specific distant metastatic sites. We observed a significant increase in disease relapse risk in luminal B1 patients compared with that in luminal A (hazard ratio: 2.157, 95% CI: 1.340-3.473, p < 0.05). Patient age, tumor size, stage, lymphovascular invasion, and receiving chemotherapy and hormone therapy were independent risk factors for metastasis and recurrence. Only the luminal B1 subtype (hazard ratio: 5.653, 95% CI: 1.166-27.409, p < 0.05) and stage (hazard ratio: 3.400, 95% CI: 1.512-7.649, p < 0.05) were identified as independent risk factors for post metastatic mortality.

CONCLUSION

Luminal B1 breast cancer has aggressive tumor biology compared with luminal A breast cancer in the follow-up period. However, there was no significant difference in the disease relapse pattern between the groups.

Ovarian Function Suppression With Luteinizing Hormone-Releasing Hormone Agonists for the Treatment of Hormone Receptor-Positive Early Breast Cancer in Premenopausal Women

Chemotherapy and endocrine therapies are mainstays of treatment for early and advanced hormone receptor-positive (HR+) breast cancer. In premenopausal women with HR+ tumors, the benefits of adding ovarian function suppression (OFS) to endocrine therapy have been debated. Consequently, for many years, tamoxifen monotherapy has been the standard of care for endocrine treatment in the adjuvant setting. Recent studies have, however, provided new evidence that, in some premenopausal patients, OFS in combination with tamoxifen or aromatase inhibitors (AIs) can significantly increase survival versus tamoxifen alone. Luteinizing hormone-releasing hormone agonists (LHRHa), including goserelin, triptorelin, and leuprorelin, achieve OFS through sustained suppression of the release of follicle-stimulating hormone and luteinizing hormone from the pituitary. In turn, this suppresses production and secretion of estradiol, an ovarian hormone that supports cancer cell growth, survival, and proliferation. In this review, we discuss the clinical evidence supporting the addition of LHRHa to adjuvant endocrine therapies, including tamoxifen and AIs, for premenopausal women with breast cancer. We also discuss the role of LHRHa use in combination with adjuvant chemotherapy to preserve ovarian function and fertility in young patients with breast cancer. Finally, we discuss important practical aspects of the use of LHRHa in breast cancer treatment, including side-effects, patient adherence to treatment, and the use of slow-release, long-acting drug formulations.

A follow-up study of a randomized controlled study evaluating safety and efficacy of leuprorelin acetate every-3-month depot for 2 versus 3 or more years with tamoxifen for 5 years as adjuvant treatment in premenopausal patients with endocrine-responsive breast cancer

Background

Previously, we conducted the 5-year open-label, randomized controlled trial (RCT) of leuprorelin adjuvant therapy in post-operative premenopausal patients with endocrine-responsive breast cancer, which was a pilot study to investigate the optimal duration of leuprorelin treatment. Since, however, long-term outcomes became required for the adjuvant endocrine therapy, we performed this follow-up observation study.

Methods

Follow-up observation study was performed up to 10th year after randomization, continuing RCT to evaluate the efficacy and safety of leuprorelin every 3 months for ≥ 3 versus 2 years, with daily tamoxifen for 5 years. Primary endpoints were disease-free survival (DFS) and 2-year landmark DFS.

Results

Eligible patients (N = 222) were randomly assigned to receive leuprorelin for either 2 years (N = 112) or ≥ 3 years (N = 110) with tamoxifen. Leuprorelin treatment for ≥ 3 years versus 2 years provided no significant difference in DFS (HR 0.944, 95% CI 0.486–1.8392) or 2-year landmark DFS (N = 99 and 102 in 2-year and ≥ 3-year groups, HR 0.834, 0.397–1.753). In small, higher-risk subgroup (n = 17); however, 2-year landmark DFS in ≥ 3-year group was significantly longer (HR 0.095, 0.011–0.850) than that in 2-year group. The incidence of bone-related adverse events was around 5% in both groups.

Conclusions

Adjuvant leuprorelin treatment for ≥ 3 years with tamoxifen only showed similar efficacy and safety profiles to those for 2 years in analyses among all patients but suggested greater benefit in higher-risk patients. No new safety signal was identified for long-term leuprorelin treatment.

Trial registration number

Not applicable. This was an observational study.

LHRH-Targeted Redox-Responsive Crosslinked Micelles Impart Selective Drug Delivery and Effective Chemotherapy in Triple-Negative Breast Cancer

Systemic chemotherapy is efficacious against triple-negative breast cancer (TNBC), but it is often associated with serious side effects. Here, a luteinizing hormone-releasing hormone (LHRH) receptor-targeted and tumor microenvironment-responsive nanoparticle system to selectively deliver chemotherapeutic drugs to TNBC cells, is reported. This delivery system (termed "LHRH-DCMs") contains poly(ethylene glycol) and dendritic cholic acid as a micellar carrier, reversible intra-micellar disulfide bond as a redox-responsive crosslink, and synthetic high-affinity (D-Lys)-LHRH peptide as a targeting moiety. LHRH-DCMs exhibit high drug loading efficiency, optimal particle size, good colloidal stability, and glutathione-responsive drug release. As expected, LHRH-DCMs are more efficiently internalized into human TNBC cells through receptor-mediated endocytosis, resulting in stronger cytotoxicity against these cancer cells than the non-targeted counterpart when encapsulated with paclitaxel (PTX). Furthermore, near-infrared fluorescence and magnetic resonance imaging demonstrate that LHRH-DCMs facilitate the tumor distribution and penetration of payloads in three different animal models of breast cancer, including cell line-derived xenograft (CDX), patient-derived xenograft (PDX), and transgenic mammary carcinoma. Finally, in vivo therapeutic studies show that PTX-LHRH-DCMs outperform both the corresponding nontargeted PTX-DCMs and the current clinical formulation (Taxol) in an orthotopic TNBC model. These results provide new insights into approaches for precise drug delivery of TNBC.

Therapy Algorithms for the Diagnosis and Treatment of Patients with Early and Advanced Breast Cancer

Background

In order to offer optimal treatment approaches based on available evidence, the Commission Breast of the Working Group Gynecologic Oncology (AGO) of the German Cancer Society developed therapy algorithms for eight complex treatment situations in primary and advanced breast cancer.

Summary

Therapy algorithms for the following complex treatment situations are outlined in this paper: (neo)adjuvant therapy of human epidermal growth factor receptor 2 (HER2)-positive breast cancer; axillary surgery and neoadjuvant chemotherapy; adjuvant endocrine therapy in premenopausal patients; adjuvant endocrine therapy in postmenopausal patients; hormone receptor (HR)-positive/HER2-negative metastatic breast cancer: strategies; HR-positive/HER2-negative metastatic breast cancer: endocrine-based first-line treatment; HER2-positive metastatic breast cancer: first to third-line; metastatic triple-negative breast cancer.

Key Messages

The therapy options shown in these algorithms are based on the current AGO recommendations updated in January 2020 but cannot represent all evidence-based treatment options. Prior therapies, performance status, comorbidities, patient preference, etc. must be taken into account for the actual treatment choice. Therefore, in individual cases, other evidence-based treatment options not listed here may also be appropriate and justified.

A Phase Ib Study of Alpelisib or Buparlisib Combined with Tamoxifen Plus Goserelin in Premenopausal Women with HR-Positive HER2-Negative Advanced Breast Cancer

PURPOSE

This study reports the MTD, recommended phase 2 dose (RP2D), and preliminary efficacy of alpelisib or buparlisib used in combination with tamoxifen plus goserelin in premenopausal patients with hormone receptor-positive (HR⁺), HER2-negative (HER2^-) advanced breast cancer (ABC).

PATIENTS AND METHODS

This study enrolled premenopausal women with HR⁺, HER2^- ABC. Patients received tamoxifen (20 mg once daily) and goserelin acetate (3.6 mg every 28 days) with either alpelisib (350 mg once daily; n = 16) or buparlisib (100 mg once daily; n = 13) in 28-day cycles until MTD was observed.

RESULTS

The criteria for MTD were not met for both alpelisib and buparlisib. The RP2D of alpelisib and buparlisib in combination with tamoxifen and goserelin were 350 mg and 100 mg, respectively. Both combinations met protocol-specified criteria for tolerability. The most common grade 3/4 treatment-emergent adverse events (TEAE) were hypokalemia (12.5%), hyperglycemia (6.3%), and rash (6.3%) for alpelisib and alanine aminotransferase increase (30.8%), aspartate aminotransferase increase (23.1%), and anxiety (15.4%) for buparlisib. TEAEs led to treatment discontinuation in 18.8% and 53.8% of alpelisib- and buparlisib-treated patients, respectively. Progression-free survival was 25.2 months in the alpelisib group and 20.6 months in the buparlisib group.

CONCLUSIONS

The RP2Ds of alpelisib and buparlisib were 350 mg and 100 mg, respectively. No unexpected safety findings were reported. Although an early-phase study, data suggest that alpelisib plus endocrine therapy may be a potentially efficacious treatment that warrants further evaluation for premenopausal patients with HR⁺, HER2^- ABC.See related commentary by Clark et al., p. 371.

GEICAM Guidelines for the Management of Patients with Breast Cancer During the COVID-19 Pandemic in Spain

Breast cancer (BC) is the most common cancer in women in Spain. During the COVID-19 pandemic caused by the SARS-CoV-2 virus, patients with BC still require timely treatment and follow-up; however, hospitals are overwhelmed with infected patients and, if exposed, patients with BC are at higher risk for infection and serious complications if infected. Thus, health care providers need to evaluate each BC treatment and in-hospital visit to minimize pandemic-associated risks while maintaining adequate treatment efficacy. Here we present a set of guidelines regarding available options for BC patient management and treatment by BC subtype in the context of the COVID-19 pandemic. Owing to the lack of evidence about COVID-19 infection, these recommendations are mainly based on expert opinion, medical organizations' and societies' recommendations, and some published evidence. We consider this a useful tool to facilitate medical decision making in this health crisis situation we are facing. IMPLICATIONS FOR PRACTICE: This work presents a set of guidelines regarding available options for breast cancer (BC) patient management and treatment by BC subtype in the context of the COVID-19 pandemic. Owing to the suddenness of this health crisis, specialists have to make decisions with little evidence at hand. Thus, these expert guidelines may be a useful tool to facilitate medical decision making in the context of a worldwide pandemic with no resources to spare.

Impressive long-term response with chemo-endocrine therapy in a premenopausal patient with metastatic breast cancer: A case report

RATIONALE

Patients with, or who develop, metastatic breast cancer have a 5-year relative survival of about 25%. Endocrine therapy clearly improves outcomes in patients with estrogen receptor-positive breast cancer. In the metastatic setting, the primary goal of treatment is to maintain long-term disease control with good quality of life. Rarely, exceptional responders achieve durable disease control, and potential cures cannot be ruled out.

PATIENT CONCERNS

We report the case of a 39-year-old woman with primary breast cancer and associated synchronous bone metastases, who experienced a disease response of 12 years with hormonal therapy as maintenance after first line chemotherapy, with a good toxicity profile.

DIAGNOSIS

The patient was diagnosed with estrogen receptor + human epidermal growth factor receptor 2 (HER2)- metastatic breast cancer with synchronous bone metastases.

INTERVENTIONS

This patient was treated with chemotherapy for 6 cycles as a first-line therapy following by endocrine treatment given as a maintenance therapy.

OUTCOMES

Our patient experienced a progression-free survival >12 years with an exceptionally good quality of life.

LESSONS

Our anecdotal experience highlights the existence of exceptional responders among patients with hormone receptor-positive metastatic breast cancer, who achieve clinical remission and durable disease control with endocrine therapy. Being able to identify these patients could help in the selection of the best treatment option among the many available.

Review of concepts in therapeutic decision-making in HER2-negative luminal metastatic breast cancer

Purpose

Hormone receptor (HR)-positive, Human epidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer (MBC) requires a therapeutic approach that takes into account multiple factors, with treatment being based on anti-estrogen hormone therapy (HT). As consensus documents are valuable tools that assist in the decision-making process for establishing clinical strategies and optimize the delivery of health services, this consensus document has been created with the aim of developing recommendations on cretiera for hormone sensitivity and resistance in HER2-negative luminal MBC and facilitating clinical decision-making.

Methods

This consensus document was generated using a modification of the RAND/UCLA methodology, which included the definition of the project and identification of issues of interest, a non-exhaustive systematic review of the literature, an analysis and synthesis of the scientific evidence, preparation of recommendations, and external evaluation with a panel of 64 medical oncologists specializing in breast cancer.

Results

A Spanish panel of experts reached consensus on 32 of the 32 recommendations/conclusions presented in the first round and were accepted with an approval rate of 100% about definition of metastatic disease not susceptible to local curative treatment, definition of hormone sensitivity and hormone resistance in metastatic luminal disease and therapeutic decision-making.

Conclusion

We have developed a consensus document with recommendations on the treatment of patients with HER2-negative luminal MBC that will help to improve therapeutic benefits.

Treatment of Advanced Hormone Receptor-Positive (HR+) HER2-negative Breast Cancer

The article gives an overview of current treatment options for metastatic hormone receptor-positive and HER2-negative breast cancer. The focus is on combined therapies, e.g., with CDK4/6 inhibition compared with purely endocrine-based therapies in the pre- and postmenopause, presenting the latest study results. The addition of a CDK4/6 inhibitor to endocrine-based therapy with an aromatase inhibitor or fulvestrant leads to a marked improvement in progression-free survival and is independently beneficial whether palbociclib, ribociclib or abemaciclib is involved. The particular clinical status of inhibition of cyclin-dependent kinases argues for its use in the first-line treatment of women with metastatic, hormone receptor-positive and HER2-negative breast cancer compared with the available purely endocrine-based therapies.

Efficacy and Safety of Palbociclib and Fulvestrant in Japanese Patients With ER+/HER2- Advanced/Metastatic Breast Cancer

BACKGROUND/AIM

Published data have shown that palbociclib-fulvestrant can significantly improve the progression-free survival (PFS) of estrogen receptor-positive/human epidermal growth factor receptor 2-negative (ER+/HER2-) metastatic breast cancer patients, but not of Japanese patients. We conducted this retrospective study to verify the efficacy and safety of palbociclib-fulvestrant in Japanese patients.

PATIENTS AND METHODS

ER+/HER2- metastatic breast cancer patients treated with fulvestrant (n=39) or palbociclib-fulvestrant (n=31) at the Saitama Medical Center from July 2012 to November 2018 were evaluated.

RESULTS

Overall response rates (ORRs) were 2.6% (fulvestrant) and 41.9% (palbociclib-fulvestrant) (p<0.001), and clinical benefit rates (CBRs) were 23.1% and 61.3% (p=0.002), respectively. The palbociclib-fulvestrant group had significantly higher CBR and PFS (hazard ratio(HR):0.272, 95% confidence interval(95CI):0.128-0.574 for PFS). Grade 3/4 neutropenia occurred in 80.6% of the palbociclib-fulvestrant group, while febrile neutropenia was not detected.

CONCLUSION

Japanese ER+/HER2- metastatic breast cancer patients tolerated palbociclib-fulvestrant, with significantly improved clinical outcomes.

Evaluating triptorelin as a treatment option for breast cancer

Introduction: Triptorelin is a luteinizing hormone-releasing hormone analog (LH-RHa) inducing ovarian function suppression (OFS). It is approved by FDA and EMA in association with tamoxifen or aromatase inhibitor (AI) and with fulvestrant and palbociclib in premenopausal women with hormone receptor (HR)-positive breast cancer. Its potential role to preserve ovarian function during chemotherapy has also been recently clarified. Areas covered: Several studies have investigated the role of adding OFS to tamoxifen and aromatase inhibitors as adjuvant treatment in early breast cancer. The addition of triptorelin is not free from adverse events as the combination with tamoxifen and exemestane resulted in an increase of endocrine-deprivation symptoms. Clinical trials have explored the combination of LH-RHa with chemotherapy in fertility preservation, demonstrating no detrimental effect on patients' oncological outcome. This is all discussed in this evaluation. Expert opinion: Triptorelin represents a standard-of-care in premenopausal women with HR-positive breast cancer and in some cases of male breast cancer. In the adjuvant setting, a personalized approach is required to combine LH-RHa with the right partner considering the risk of recurrence and the toxicity profile. LH-RHa may be offered to breast cancer patients in the hope of reducing the likelihood of chemotherapy-induced ovarian insufficiency.

Endocrine Therapy-Induced Alopecia in Patients With Breast Cancer

Importance

Endocrine therapy-induced alopecia (EIA) has been anecdotally reported but not systematically described.

Objective

To characterize EIA in patients with breast cancer.

Design, Setting, and Participants

Retrospective cohort study of 112 patients with breast cancer, diagnosed with EIA from January 1, 2009, to December 31, 2016, the patients were examined at the dermatology service in a large tertiary care hospital and comprehensive cancer center.

Main Outcomes and Measures

The clinical features, alopecia-related quality of life (QoL), and response to minoxidil of EIA in patients with breast cancer were assessed. Data from the Hairdex Questionnaire was used to assess the impact of the alopecia on patients QoL. Higher score indicates lower QoL (0-100 score). Efficacy of minoxidil was measured at 3 or 6 months by a single-blinded investigator through standardized clinical photographs of the scalp.

Results

A total of 112 female patients with breast cancer were included (median [range] age, 60 [34-90] years). A total of 104 patients (93%) had standardized clinical photographs; of these, 59 patients (53%) had trichoscopy images available at baseline, and 46 patients (41%) were assessed for response to minoxidil. Alopecia was attributed to aromatase inhibitors in 75 patients (67%) and tamoxifen in 37 (33%). Severity was grade 1 in 96 of 104 patients (92%), and the pattern was similar to androgenetic alopecia. The predominant trichoscopic feature at baseline was the presence of vellus hairs and intermediate- and thick-diameter terminal hair shafts. A negative impact on QoL was reported, with a higher effect in the emotion domain according to the Hairdex score (mean [SD], 41.8 [21.3]; P < .001). After treatment with topical minoxidil, moderate or significant improvement in alopecia was observed in 37 of 46 patients (80%).

Conclusions and Relevance

Endocrine therapies are associated with a pattern alopecia similar to androgenetic-type, consistent with the mechanism of action of causal agents. A significant negative impact on QoL was reported by patients, despite mostly mild alopecia severity.

Endocrine and Targeted Therapy for Hormone-Receptor-Positive, HER2-Negative Advanced Breast Cancer: Insights to Sequencing Treatment and Overcoming Resistance Based on Clinical Trials

Background: Advanced hormone-receptor positive HER2 negative breast cancer is a common and a very heterogeneous disease. Hormone therapy is the main first line treatment of choice, given alone or in combination with other agents that have shown to improve patient outcomes, Nevertheless, treatment remains generally palliative rather than curative. Sequencing of such treatment remains challenging, especially with resurgence of variable resistance patterns. Multiple attempts have been made to overcome resistance and improve patient survival, yet resistance remains not very well understood and metastatic cancer remains a disease with dismal prognosis.

Methods: In this paper, we searched pubmed database as well as local and international meetings for all studies discussing advanced and metastatic hormone-receptor-positive, her2-negative breast cancer, hormonal treatment, resistance to hormonal treatment, mechanism of resistance, and means to overcome such resistance.

Conclusion: There does not exist an optimal treatment sequence for hormone-receptor-positive, her2-negative advanced breast cancer. However, after review of literature, a reasonable approach may be starting with tamoxifen, aromatase inhibitors, or fulvestrant in absence of visceral crisis, in addition to ensuring adequate ovarian function suppression in pre/peri-menopausal women. Aromatase inhibitors and fulvestrant seem to be superior. Resistance to such agents is increasing, mostly attributed to genetic and molecular changes. Multiple modalities are addressed to overcome such resistance including use of CKD4/6 inhibitors, mTOR inhibitors and PI3K inhibitors in addition to other agents under study, all with promising results. CDK4/6 inhibitors work best when used in frontline setting. Finally, treatment of breast cancer remains a growing field, and more studies are to be awaited.

Hot-Melt Preparation of a Non-Biodegradable Peptide Implant: A Proof of Principle

BACKGROUND

Both biodegradable and non-biodegradable peptide-loaded implants are already developed for the long-term treatment of patients, thereby reducing the frequency of drug administration. To further improve peptide formulation, extending the scope of implant-based drug delivery systems towards other polymers and processing techniques is highly interesting.

OBJECTIVE

In this study, as a proof-of-principle, the feasibility of hot-melt processing of a peptide active pharmaceutical ingredient was assessed by developing a non-biodegradable poly(ethylenevinyl acetate) (33% VA) implant loaded with 20% (w/w) buserelin acetate.

METHODS

Cross-sectional implant characterization was performed by Raman microscopy. The stability of buserelin acetate in the polymeric matrix was evaluated for 3 months under ICH stability conditions and the quantity as well as the degradation products analyzed using LC-UV methods. An in vitro dissolution study was performed as well and buserelin acetate and its degradants analyzed using the same chromatographic methods.

RESULTS

No significant quantities of buserelin acetate-related degradation products were formed during the hot-melt preparation as well as during the stability study. Together with the consistent buserelin acetate assay values over time, chemical peptide stability was thus demonstrated. The in vitro buserelin acetate release from the implant was found to be diffusion-controlled after an initial burst release, with stable release profiles in the stability study, demonstrating the functional stability of the peptide implant.

CONCLUSION

These results indicate the feasibility of preparing non-biodegradable peptide-loaded implants using the hot-melt production method and may act as a proof of principle concept for further innovation in peptide medicinal formulations.

GPCR Modulation in Breast Cancer

Breast cancer is the most prevalent cancer found in women living in developed countries. Endocrine therapy is the mainstay of treatment for hormone-responsive breast tumors (about 70% of all breast cancers) and implies the use of selective estrogen receptor modulators and aromatase inhibitors. In contrast, triple-negative breast cancer (TNBC), a highly heterogeneous disease that may account for up to 24% of all newly diagnosed cases, is hormone-independent and characterized by a poor prognosis. As drug resistance is common in all breast cancer subtypes despite the different treatment modalities, novel therapies targeting signaling transduction pathways involved in the processes of breast carcinogenesis, tumor promotion and metastasis have been subject to accurate consideration. G protein-coupled receptors (GPCRs) are the largest family of cell-surface receptors involved in the development and progression of many tumors including breast cancer. Here we discuss data regarding GPCR-mediated signaling, pharmacological properties and biological outputs toward breast cancer tumorigenesis and metastasis. Furthermore, we address several drugs that have shown an unexpected opportunity to interfere with GPCR-based breast tumorigenic signals.

Breast cancer in adolescents and young adults

Breast cancer is the most common cancer of adolescents and young adult (AYA) women aged 15 to 39 years, accounting for 5.6% of all invasive breast cancer in women. In comparison with older women, AYAs are more likely to have familial cancer predisposition genes, larger breast tumors, unfavorable biological characteristics, distant metastatic disease at diagnosis, and adverse outcome. Endocrine therapy and some chemotherapy recommendations differ between young and older women. AYAs require coordinated multidisciplinary care, treatment regimens that minimize late effects such as premature menopause and osteoporosis, and proactive management of psychological and sexual health during and after cancer treatment.

Interdisciplinary Screening, Diagnosis, Therapy and Follow-up of Breast Cancer. Guideline of the DGGG and the DKG (S3-Level, AWMF Registry Number 032/045OL, December 2017) - Part 2 with Recommendations for the Therapy of Primary, Recurrent and Advanced Breast Cancer

Purpose The aim of this official guideline coordinated and published by the German Society for Gynecology and Obstetrics (DGGG) and the German Cancer Society (DKG) was to optimize the screening, diagnosis, therapy and follow-up care of breast cancer. Method The process of updating the S3 guideline published in 2012 was based on the adaptation of identified source guidelines. They were combined with reviews of evidence compiled using PICO (Patients/Interventions/Control/Outcome) questions and with the results of a systematic search of literature databases followed by the selection and evaluation of the identified literature. The interdisciplinary working groups took the identified materials as their starting point and used them to develop suggestions for recommendations and statements, which were then modified and graded in a structured consensus process procedure. Recommendations Part 2 of this short version of the guideline presents recommendations for the therapy of primary, recurrent and metastatic breast cancer. Loco-regional therapies are de-escalated in the current guideline. In addition to reducing the safety margins for surgical procedures, the guideline also recommends reducing the radicality of axillary surgery. The choice and extent of systemic therapy depends on the respective tumor biology. New substances are becoming available, particularly to treat metastatic breast cancer.

Fulvestrant plus goserelin versus anastrozole plus goserelin versus goserelin alone for hormone receptor-positive, HER2-negative tamoxifen-pretreated premenopausal women with recurrent or metastatic breast cancer (KCSG BR10-04): a multicentre, open-label, three-arm, randomised phase II trial (FLAG study)

BACKGROUND

We investigated the efficacy and safety of fulvestrant plus goserelin (F + G) versus anastrozole plus goserelin (A + G) in comparison with goserelin (G) alone in premenopausal women with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-), tamoxifen-pretreated metastatic breast cancer (MBC).

PATIENTS AND METHODS

In this multicentre, open-label, randomised phase II study, premenopausal women aged ≥18 years with HR+, HER2-, tamoxifen-pretreated MBC were randomly assigned (1:1:1) to F + G, A + G or G alone. The primary end-point was time to progression (TTP). Secondary end-points included overall survival, overall response rate, clinical benefit rate and toxicity.

RESULTS

Of 138 eligible patients, 44 were randomly assigned to receive F + G, 47 to A + G and 47 to G alone. The median follow-up duration was 32.2 months (interquartile range: 23.69-40.86) and the median age was 43.0 years (range 23.0-55.0). The median TTP was 16.3 months (95% confidence interval [CI] 7.5-25.1) for F + G, 14.5 months (95% CI 11.0-18.0) for A + G and 13.5 months (95% CI 10.3-16.8) for G alone. Compared with G alone, the hazard ratios were 0.608 for F + G (95% CI, 0.370-0.998; p = 0.049) and 0.982 for A + G (95% CI, 0.624-1.546; p = 0.937). In terms of visceral metastasis, a stratification factor, there were no TTP differences according to treatment arm. Grade III or IV toxicities were rarely observed. Of the common adverse events, grade I arthralgia and joint stiffness were more frequently observed in the F + G than in the A + G or G-alone groups (p < 0.05, respectively).

CONCLUSIONS

F + G provides a promising new option for the treatment of premenopausal women with HR+, HER2-, tamoxifen-pretreated MBC.

TRIAL REGISTRATION

ClinicalTrials.gov number NCT01266213 and Korean Cancer Study Group (KCSG) Breast cancer protocol number BR10-04.

Current Landscape of Targeted Therapies for Hormone-Receptor Positive, HER2 Negative Metastatic Breast Cancer

The majority of deaths from MBC are in patients with hormone receptor (HR) positive, HER2 negative disease. Endocrine therapy (ET) remains the backbone of treatment in these cases, improving survival and quality of life. However, treatment can lose effectiveness due to primary or acquired endocrine resistance. Analysis of mechanisms of ET resistance has led to the development of a new generation of targeted therapies for advanced breast cancer. In addition to anti-estrogen therapy with selective estrogen receptor modulators, aromatase inhibitors, and/or selective estrogen receptor degraders, combinations with cyclin dependent kinase (CDK) 4/6 inhibitors have led to substantial progression free survival (PFS) improvements in the first and second line settings. While the PI3K/AKT/mTOR pathway is known to be an important growth pathway in HR positive breast cancer, PI3K inhibitors have been disappointing due to modest effect sizes and significant toxicity. The mTOR inhibitor everolimus significantly improves progression free survival when added to ET, and recent studies have improved supportive care allowing less toxicity. While these combination targeted therapies improve outcomes and often delay initiation of chemotherapy, long term overall survival data are lacking and data for the ideal strategy for sequencing these agents remains unclear. Ongoing research evaluating potential biomarkers and mechanisms of resistance is anticipated to continue to improve outcomes for patients with HR positive metastatic breast cancer. In this review, we will discuss management and ongoing challenges in the treatment of advanced HR positive, HER2 negative breast cancer, highlighting single agent and combination endocrine therapies, targeted therapies including palbociclib, ribociclib, abemaciclib, and everolimus, and sequencing of therapies in the clinic.

Endocrine Therapy in Premenopausal Hormone Receptor Positive/Human Epidermal Growth Receptor 2 Negative Metastatic Breast Cancer: Between Guidelines and Literature

There is growing interest in the endocrine treatment (ET) of premenopausal women with hormone receptor positive (HR+) metastatic breast cancer (MBC). This review summarizes available data on endocrine therapy for this patient subset and aims to define the most appropriate treatment approach. The combination of luteinizing hormone-releasing hormone (LHRH) agonists plus tamoxifen seems effective and safe and is considered as being superior to either approach alone; still, single-agent therapy remains an acceptable treatment option. Due to their mechanism of action, aromatase inhibitors alone are not suitable for the treatment of premenopausal patients, but the combination with LHRH agonists may result in excellent disease control. Fulvestrant, in conjunction with LHRH agonists, also yields interesting results regarding clinical benefit rate and time to progression; currently, other orally available selective estrogen receptor downregulators are under clinical evaluation. Recently, targeted drugs have been added to ET in order to reverse endocrine resistance, but only limited information regarding their activity in premenopausal patients is available. The cyclin dependent kinase 4 and 6 inhibitor palbociclib when combined with fulvestrant and LHRH agonists was shown to prolong progression-free survival over endocrine therapy alone in pretreated patients; similar results were obtained with the addition of abemacicilib or ribociclib to endocrine therapy. Currently, activity of the mammalian target of rapamycin inhibitor everolimus in combination with letrozole and goserelin is under assessment in premenopausal patients after progression on tamoxifen (MIRACLE trial).

IMPLICATIONS FOR PRACTICE

This review provides clinicians with an overview on the available data regarding endocrine treatment of hormone receptor positive (HR+) metastatic breast cancer (MBC) in premenopausal women and summarizes the treatment options available in routine clinical practice. Knowledge of an up-to-date therapeutic approach in women with premenopausal HR+ MBC will lead to better disease management, thereby improving disease control and quality of life while minimizing side effects.

Targeted Therapy for Premenopausal Women with HR+, HER2- Advanced Breast Cancer: Focus on Special Considerations and Latest Advances

The incidence of advanced breast cancer in premenopausal women is increasing, and breast cancer in younger women is often more aggressive and has a worse prognosis compared with breast cancer in older women. Premenopausal women with hormone receptor-positive (HR⁺) breast cancer are frequently under-represented in clinical trials, and treatment strategies in the premenopausal setting are usually extrapolated from data from postmenopausal patients, with the addition of ovarian function suppression to endocrine therapy in HR⁺ disease. However, the underlying biology of breast cancer in premenopausal women can be different from postmenopausal women, and treatment strategies should ideally be specifically tested in premenopausal patients. Recent phase III trials have now investigated cyclin-dependent kinase 4/6 (CDK4/6) inhibitors in premenopausal patients with HR⁺, HER2^- advanced breast cancer: Palbociclib and abemaciclib have been tested in a subset of premenopausal patients in the PALOMA-3 and MONARCH-2 studies, and ribociclib has been tested in the phase III MONALEESA-7 trial, which was entirely dedicated to premenopausal women. This comprehensive review summarizes the differences in the biology of HR⁺, HER2^- breast cancer in the premenopausal population compared with the postmenopausal population; discusses special considerations for treatment of premenopausal women; and reviews the evidence from clinical trials investigating endocrine therapy, other targeted treatments, and ovarian function suppression in the HR⁺, HER2^- advanced breast cancer setting. Clin Cancer Res; 24(21); 5206-18. ©2018 AACR.

Hormone receptor-positive, HER2-negative metastatic breast cancer: redrawing the lines

Estrogen receptor modulators and estrogen deprivation have become standards of care for hormone receptor-positive metastatic breast cancer. However, after traditional first-line endocrine monotherapy treatment, the disease typically progresses despite the initial high rate of clinical benefit. Multiple studies have aimed at optimizing treatment strategies to improve upon clinical benefit beyond the traditional single-agent endocrine treatment. With the availability of new data and novel therapies, the clinical practice challenge becomes how best to define the optimal treatment sequence to maximize clinical benefit. In this review, we present treatment options clinically relevant to the management of hormone-positive, her2-negative metastatic breast cancer, and we propose a treatment algorithm based on the current literature.

Aromatase inhibitors in premenopausal women with breast cancer: the state of the art and future prospects

Approximately 11% of patients with breast cancer (bca) are diagnosed before menopause, and because in most of those patients the tumour expresses a hormone receptor, treatment with endocrine interventions can be applied in any setting of disease (early or advanced). In the past, hormonal treatment consisted only of the estrogen receptor modulator tamoxifen, associated with luteinizing hormone-releasing hormone (lhrh); more recently, aromatase inhibitors (ais) have come into widespread use. The ais interfere with the last enzymatic step of estrogen synthesis in which androgens are converted into estrogens. Initially, the ais were used alone in postmenopausal patients to prevent disease recurrence, but together with lhrh analogs, they can be used in premenopausal patients to produce better estrogen suppression than can be achieved with tamoxifen plus a lhrh analog. Using a systematic review of the scientific literature (prospective and retrospective studies), we set out to assess the efficacy of ais compared with other endocrine therapy in various disease settings (neoadjuvant, adjuvant, metastatic).

CTMP, a predictive biomarker for trastuzumab resistance in HER2-enriched breast cancer patient

Trastuzumab is regarded as the primary therapy for patients with HER2-enriched breast cancer, but the pathological complete response for advanced cases is less than 30%. The underlying mechanism of trastuzumab resistance remains unclear and there are currently no conclusive biomarkers for patient response to trastuzumab. Identifying predictive biomarkers for trastuzumab response may allow treatments to be individually tailored and optimized multi-target therapies may be developed. CTMP activates AKT signaling in breast cancer and over-activation of AKT has been reported to contribute to trastuzumab resistance. In this study, we examined samples from 369 patients to investigate the correlation between CTMP expression level and patient outcome. Elevated CTMP expression was correlated with adverse outcomes in HER2-enriched patients including overall and disease-free survival as well as trastuzumab resistance. Ectopic expression of varying levels of CTMP in SkBR3 cells dose-dependently attenuated trastuzumab-mediated growth inhibition through AKT activation. In addition, inhibition of AKT signaling by AKT inhibitor IV and Rapamycin reversed CTMP-mediated trastuzumab resistance. In clinical samples, the high expression of CTMP was showed in trastuzumab non-responders and positively correlated with AKT activity. Taken together, we demonstrated that CTMP promotes AKT activation resulting in trastuzumab resistance in patients with HER2-enriched breast cancer. High CTMP expression not only predicted poor prognosis, but may also predict resistance to trastuzumab in HER2-enriched patients. Therefore, CTMP expression may be considered as a prognostic biomarker in HER2-enriched breast cancer and high expression may indicate a utility for AKT-inhibition in these patients.

Discordant Results Obtained for Different Methods of HER-2/Neu Testing in Breast Cancer – A Question of Standardization, Automation and Timing

Background

HER-2/neu positivity is required for the selection of stage IV breast cancer patients for trastuzumab therapy. We compared the results of the recommended immunohistochemistry (IHC) evaluation with the automated ACIS™ IHC system and with fluorescence in situ hybridization (FISH). These HER-2/neu tissue results were correlated with the serum HER-2/neu (sHER-2/neu) levels at the time of metastatic spread.

Patients and Methods

A total of 61 IHC slides from 30 patients were stained using the HercepTest™. HER-2/neu gene amplification was determined using the Ventana™ FISH assay. sHER-2/neu levels were measured with the Oncogene Science” ELISA kit. The concordance of HER-2/neu results was determined using the concordance index Kappa (κ).

Results

The best concordance between any IHC and FISH was found for the automated ACIS system (88.5%, κ=0.68, category “good”). The comparison between the manual interpretations and the automated IHC was categorized as “very good” (95.1%, κ=0.85). The median sHER-2/neu level of FISH positive patients was significantly higher (67 ng/mL) than that of FISH negative patients (17 ng/mL, p=0.018). The increase in HER-2/neu positivity comparing tissue to stage IV serum was statistically significant (p=0.001).

Conclusions

The concordance between conventional IHC and computerized analysis was very good. The number of patients with stage IV breast cancer with an elevated sHER-2/neu level was much higher than HER-2/neu positivity in tissue. This discrepancy is only partially explained by the influence of tumor load. Patients with an elevated sHER-2/neu level and no tissue overexpression should be considered for retesting of tissue or a new biopsy.

Metastatic breast cancer: Endocrine therapy landscape reshaped

Endocrine therapy (ET) of hormone receptor (HR)-positive and human epidermal growth factor receptor 2-(HER2)-negative metastatic breast cancer (MBC) historically focused on estrogen deprivation and antagonism. The identification of several intracellular pathways promoting resistance to antiestrogen therapy led to the introduction of novel endocrine drug combinations that reformed treatment schema and expanded therapeutic options. There is no doubt that efforts to overcome or delay resistance to ET are fruiting, particularly with the introduction of cyclin-dependent kinase 4/6 inhibitors such as palbociclib and ribociclib, and mechanistic target of rapamycin inhibitors such as everolimus. Although still considered incurable by currently available treatment modalities, many patients with MBC nowadays enjoy several years of good quality life coupled with decent tumor control. The diversity of therapies and unusual pattern of side effects can be quite perplexing to the treating physician. The sequence of variable agents and management of side effects, in addition to the timing of initiation of cytotoxic chemotherapy, is among the challenges faced by oncologists. In this review, we shed a spotlight on mechanisms of resistance to ET, and provide a review of landmark studies that have recently reshaped the landscape of treatment options for patients with metastatic HR-positive, HER2-negative MBC. A suggested treatment strategy for newly diagnosed patients is also discussed herein.

Comparison of quality of life between 2-year and 3-or-more-year administration of leuprorelin acetate every-3-months depot in combination with tamoxifen as adjuvant endocrine treatment in premenopausal patients with endocrine-responsive breast cancer: a randomized controlled trial

Background

We conducted an open-label, randomized controlled trial evaluating the appropriate treatment duration of leuprorelin acetate 3-month depot, TAP-144-SR (3M), administered postsurgically every 3 months for 2 years versus 3 or more (up to 5) years, in combination with tamoxifen, for 5 years in premenopausal endocrine-responsive breast cancer patients and reported similar survival benefit in the two treatment groups. We hereby present patient-reported quality of life (QOL) data obtained from this trial.

Methods

Three self-administered QOL questionnaires (QOL-ACD, QOL-ACD-B, FACT-ES subscale) were used, and the difference in QOL score changes between the two groups was analyzed using a mixed-effects model for repeated measures.

Results

Eligible patients (N = 222) were randomly assigned to a 2-year (2YG, N = 112) or 3-or-more-year treatment group (3YG, N = 110). The time courses of the three QOL scores during the trial period were similar in the two groups. The mean changes in the QOL scores from week 96 were largely stable through week 240 in the 3YG, but showed significantly greater improvement in the score changes from week 96 in the 2YG than the 3YG. Symptoms associated with menopause such as hot flashes and sweating contributed to these results. Menstruation recovery was associated with significantly greater improvement of these symptoms in the 2YG than the 3YG.

Conclusions

Patient-reported menopause-associated symptoms and QOL improved after discontinuation of the LH-RH agonist administration and menstruation recovery. QOL information should be a consideration in long-term treatment.

The Role of Gonadotropin-Releasing-Hormone Analogues in the Treatment of Breast Cancer

The prognosis of premenopausal breast cancer patients with early disease has improved over the past decades, particularly in women expressing hormone receptors in their tumors. Tamoxifen, a selective estrogen receptor modulator, has dramatically changed outcomes in these patients and remains one of the standards of care. Ovarian function suppression by gonadotropin-releasing-hormone analogues (GnRHa) represents an additional treatment option. Long-term data are required before firm conclusions can be drawn, whereas recent clinical trials suggest that the use of GnRHa is effective in both adjuvant and metastatic settings, particularly in younger patients (<35 years old). The decision to select the optimal therapy should be individualized according to the biological characteristics of tumors, estimates of disease response, comorbidities, patient preference, and long-term toxicity.

Phosphatidylinositol-3 Kinase Inhibitors, Buparlisib and Alpelisib, Sensitize Estrogen Receptor-positive Breast Cancer Cells to Tamoxifen

Tamoxifen is the standard first-line hormonal therapy for premenopausal women with estrogen receptor (ER)-positive metastatic breast cancer (BC). One of the crucial mechanisms underlying hormonal therapy resistance is the collateral activation of the phosphatidylinositol-3 kinase (PI3K)/AKT pathway. We explored whether PI3K inhibitors, buparlisib and alpelisib, enhance the efficacy of tamoxifen against ER-positive BC cells. We have observed a synergism between alpelisib or buparlisib and tamoxifen in the treatment for ER-positive BC cell lines harboring different PI3K alterations. Immunoblotting analysis showed alpelisib, buparlisib, or either drug in combination with tamoxifen downregulated the PI3K downstream targets in the MCF-7 and ZR75-1 cells. In the MCF-7 cells transfected with a constitutive active (myristoylated) AKT1 construct or mutant ER, the synergistic effect between alpelisib and tamoxifen was markedly attenuated, indicating that synergism depends on AKT inhibition or normally functioning ER. Combining alpelisib or buparlisib with tamoxifen also attenuated MCF-7 tumor growth in Balb/c nude mice. Our data suggest that additional PI3K blockade might be effective in enhancing the therapeutic effect of tamoxifen in ER-positive BC and support the rationale combination in clinical trials.

Palbociclib Combined with Fulvestrant in Premenopausal Women with Advanced Breast Cancer and Prior Progression on Endocrine Therapy: PALOMA-3 Results

BACKGROUND

The efficacy and safety of palbociclib, a cyclin-dependent kinase 4/6 inhibitor, combined with fulvestrant and goserelin was assessed in premenopausal women with advanced breast cancer (ABC) who had progressed on prior endocrine therapy (ET).

PATIENTS AND METHODS

One hundred eight premenopausal endocrine-refractory women ≥18 years with hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2-) ABC were among 521 women randomized 2:1 (347:174) to fulvestrant (500 mg) ± goserelin with either palbociclib (125 mg/day orally, 3 weeks on, 1 week off) or placebo. This analysis assessed whether the overall tolerable safety profile and significant progression-free survival (PFS) improvement extended to premenopausal women. Potential drug-drug interactions (DDIs) and ovarian suppression with goserelin were assessed via plasma pharmacokinetics and biochemical analyses, respectively. (ClinicalTrials.gov identifier: NCT01942135) RESULTS: Median PFS for premenopausal women in the palbociclib (n = 72) versus placebo arm (n = 36) was 9.5 versus 5.6 months, respectively (hazard ratio, 0.50, 95% confidence interval: 0.29-0.87), and consistent with the significant PFS improvement in the same arms for postmenopausal women. Any-grade and grade ≤3 neutropenia, leukopenia, and infections were among the most frequent adverse events reported in the palbociclib arm with concurrent goserelin administration. Hormone concentrations were similar between treatment arms and confirmed sustained ovarian suppression. Clinically relevant DDIs were not observed.

CONCLUSION

Palbociclib combined with fulvestrant and goserelin was an effective and well-tolerated treatment for premenopausal women with prior endocrine-resistant HR+/HER2- ABC. Inclusion of both premenopausal and postmenopausal women in pivotal combination ET trials facilitates access to novel drugs for young women and should be considered as a new standard for clinical trial design.

IMPLICATIONS FOR PRACTICE

PALOMA-3, the first registrational study to include premenopausal women in a trial investigating a CDK4/6 inhibitor combined with endocrine therapy, has the largest premenopausal cohort reported in an endocrine-resistant setting. In pretreated premenopausal women with hormone receptor-positive advanced breast cancer, palbociclib plus fulvestrant and goserelin (luteinizing hormone-releasing hormone [LHRH] agonist) treatment almost doubled median progression-free survival (PFS) and significantly increased the objective response rate versus endocrine monotherapy, achieving results comparable to those reported for chemotherapy without apparently interfering with LHRH agonist-induced ovarian suppression. The significant PFS gain and tolerable safety profile strongly support use of this regimen in premenopausal women with endocrine-resistant disease who could possibly delay chemotherapy.

Advances in systemic therapy for metastatic breast cancer: future perspectives

Breast cancer (BC) is the most common cancer in women worldwide. One in eight women will develop the disease in her lifetime. Notwithstanding the incredible progress made in this field, BC still represents the second most common cause of cancer-related death in women. Targeted drugs have revolutionised breast cancer treatment and improved the prognosis as well as the life expectancy of millions of women. However, the phenomenon of primary and secondary pharmacological resistance is becoming increasingly evident, limiting the efficacy of these agents and calling for a better in-depth knowledge and understanding of the biology as well as the biochemical crosstalk underlying the disease. The advent of laboratory technologies in the clinical setting such as the routine use of next generation sequencing has allowed identification of new genetic alterations as well as providing a precise picture of the molecular landscapes of each tumour. Consequently, new specific therapeutic approaches are becoming available to minimise or delay the occurrence of resistance. In this review, we analyse the latest research and news from the clinical development side for each BC subtype.

Breast cancer

Breast cancer is one of the three most common cancers worldwide. Early breast cancer is considered potentially curable. Therapy has progressed substantially over the past years with a reduction in therapy intensity, both for locoregional and systemic therapy; avoiding overtreatment but also undertreatment has become a major focus. Therapy concepts follow a curative intent and need to be decided in a multidisciplinary setting, taking molecular subtype and locoregional tumour load into account. Primary conventional surgery is not the optimal choice for all patients any more. In triple-negative and HER2-positive early breast cancer, neoadjuvant therapy has become a commonly used option. Depending on clinical tumour subtype, therapeutic backbones include endocrine therapy, anti-HER2 targeting, and chemotherapy. In metastatic breast cancer, therapy goals are prolongation of survival and maintaining quality of life. Advances in endocrine therapies and combinations, as well as targeting of HER2, and the promise of newer targeted therapies make the prospect of long-term disease control in metastatic breast cancer an increasing reality.

Overview of elagolix for the treatment of endometriosis

INTRODUCTION

Suppression of sex-steroid secretion is required in a variety of gynecological conditions. This can be achieved using gonadotropin releasing hormone (GnRH) agonists that bind pituitary gonadotropin receptors and antagonize the link-receptor of endogenous GnRH, inhibiting the mechanism of GnRH pulsatility. On the other hand, GnRH antagonists immediately reduce gonadal steroid levels, avoiding the initial stimulatory phase of the agonists. Potential benefits of GnRH antagonists over GnRH agonists include a rapid onset and reversibility of action. Older GnRH antagonists are synthetic peptides, obtained by modifications of certain amino acids in the native GnRH sequence. They require subcutaneous injections, implantation of long-acting depots. The peptide structure is responsible for histamine-related adverse events and the tendency to elicit hypersensitivity reactions.

AREAS COVERED

Research has worked towards the development of non-peptidic molecules exerting antagonist action on GnRH. They are available for oral administration and may have a more beneficial safety profile in comparison with peptide GnRH antagonists. This article focuses on the data of the literature about elagolix, a novel non-peptidic GnRHantagonist, in the treatment of endometriosis.

EXPERT OPINION

Elagolix demonstrated efficacy in the management of endometriosis-associated pain and had an acceptable safety and tolerability profile. However, further studies are necessary to evaluate its non-inferiority in comparison with other endometriosis's treatments.

A case of premenopausal breast cancer with symptomatic cerebellar metastasis successfully treated by systemic endocrine therapy alone: relationship to biological features

We report a case of premenopausal breast cancer with symptomatic cerebellar metastasis successfully treated by systemic endocrine therapy alone. The patient developed dysarthria, headache, lightheadedness and became difficult to write gradually. The cerebellar tumor was detected by computed tomography (CT) and was suspected hemangioma or hemangioblastoma. The tumor was resected and histologically diagnosed as poorly differentiated adenocarcinoma or squamous cell carcinoma. A whole body CT scan revealed a right thyroid tumor and left breast tumor. Core needle biopsy of the breast tumor histologically diagnosed the tumor as estrogen receptor positive, progesterone receptor positive, human epidermal growth factor receptor-2 negative, and Ki-67 labeling index 5%. After these examinations, histologically, the resected cerebellar tumor showed the same subtype as the breast tumor, so the final diagnosis was metastatic breast cancer with cerebellar metastasis. The patient subsequently received radiotherapy with the CyberKnife and endocrine therapy without resection of the thyroid tumor. Her medical condition has maintained a good response and stable disease for 7.5 years after the start of treatment. Analysis of four ESR1 mutations showed no mutations in the cerebellar metastatic lesion and breast cancer tissue. Our findings show that these tumors have high hormone responsiveness.

Endocrine Therapy in Premenopausal Hormone Receptor-Positive Breast Cancer

Systemic therapy for premenopausal women with hormone receptor-positive breast cancer has evolved in the last 5 years, but critical questions remain. Recent randomized trials have demonstrated a benefit for the addition of ovarian suppression to endocrine therapy in patients with breast cancers considered to be at high risk for recurrence, whereas those with lower-risk cancers seem to have a favorable outcome with tamoxifen alone. Two large randomized trials have demonstrated a benefit for extending adjuvant tamoxifen beyond 5 years. Currently the choice of systemic therapy is selected empirically but molecular profiling may, in the near future, provide a more conclusive means of selecting an endocrine therapeutic approach for premenopausal patients. Given that a significant subset of hormone receptor-positive cancers are intrinsically resistant to endocrine agents, as well as the finding that inhibiting cyclin-dependent kinases 4 and 6 and mammalian target of rapamycin appears to potentially reverse this resistance in patients with metastatic disease, evaluation of these agents in the early-stage setting is ongoing.

Metastatic breast cancer: The Odyssey of personalization

Metastatic breast cancer is the most frequent cause of cancer death for women worldwide. In the last 15 years, a large number of new agents have entered clinical use, a result of the dramatic increase in our understanding of the molecular underpinnings of metastatic breast cancer. However, while these agents have led to better outcomes, they are also at the root cause of increasing financial pressure on healthcare systems. Moreover, decision making in an era where every year new agents are added to the therapeutic armamentarium has also become a significant challenge for medical oncologists. In the present article, we will provide an ample review on the most recent developments in the field of treatment of the different subtypes of metastatic breast cancer with a critical discussion on the slow progress made in identifying response biomarkers. New hopes in the form of ctDNA monitoring and functional imaging will be presented.

Endocrine therapy and strategies to overcome therapeutic resistance in breast cancer

Despite the remarkable success of endocrine therapy in the treatment of patients with estrogen receptor (ER)- positive breast cancer, not all patients derive benefit from such therapy, or may benefit only temporarily before disease progression or relapse occurs. The value of endocrine therapy, which blocks ER signaling by a variety of strategies, lies in its simplicity, lower toxicity, and better alignment with preserved quality of life, particularly when compared to chemotherapy, which is more toxic and has only modest benefits for many patients with ER-positive breast cancer. It is therefore critical that we discover ways to extend endocrine therapy benefit in patients and prevent therapeutic resistance whenever possible. The tremendous evolution in our understanding of endocrine resistance mechanisms, coupled with the increasing availability of novel agents that target resistance pathways, has led to enhanced treatment approaches for patients with ER-positive breast cancer, primarily through combinations of endocrine agents with a variety of pathway inhibitors. Despite these treatment advances and our changing view of ER-positive breast cancer, there is much work that needs to be done. It remains a problem that we cannot reliably predict which subsets of patients will experience disease relapse or progression on endocrine therapy, and as such, combination strategies with targeted agents have largely been used in unselected patients with ER-positive breast cancer, including those who continue to have endocrine-sensitive disease. Patient selection is a significant issue since most of the targeted therapeutics that we use with endocrine therapy are expensive and can be toxic, and we may be inadvertently overtreating patients whose disease can still be controlled with endocrine therapy alone. In this article, we will review current and future strategies in the treatment of ER-positive breast cancer, as well as the evolving role of targeted therapy in the management of endocrine-resistance.

Defining the optimal sequence for the systemic treatment of metastatic breast cancer

Metastatic breast cancer is a heterogeneous disease that presents in varying forms, and a growing number of therapeutic options makes it difficult to determine the best choice in each particular situation. When selecting a systemic treatment, it is important to consider the medication administered in the previous stages, such as acquired resistance, type of progression, time to relapse, tumor aggressiveness, age, comorbidities, pre- and post-menopausal status, and patient preferences. Moreover, tumor genomic signatures can identify different subtypes, which can be used to create patient profiles and design specific therapies. However, there is no consensus regarding the best treatment sequence for each subgroup of patients. During the SABCC Congress of 2014, specialized breast cancer oncologists from referral hospitals in Europe met to define patient profiles and to determine specific treatment sequences for each one. Conclusions were then debated in a final meeting in which a relative degree of consensus for each treatment sequence was established. Four patient profiles were defined according to established breast cancer phenotypes: pre-menopausal patients with luminal subtype, post-menopausal patients with luminal subtype, patients with triple-negative subtype, and patients with HER2-positive subtype. A treatment sequence was then defined, consisting of hormonal therapy with tamoxifen, aromatase inhibitors, fulvestrant, and mTOR inhibitors for pre- and post-menopausal patien ts; a chemotherapy sequence for the first, second, and further lines for luminal and triple-negative patients; and an optimal sequence for treatment with new antiHER2 therapies. Finally, a document detailing all treatment sequences, that had the agreement of all the oncologists, was drawn up as a guideline and advocacy tool for professionals treating patients with this disease.

Endocrine Therapy for Hormone Receptor-Positive Metastatic Breast Cancer: American Society of Clinical Oncology Guideline

PURPOSE

To develop recommendations about endocrine therapy for women with hormone receptor (HR) -positive metastatic breast cancer (MBC).

METHODS

The American Society of Clinical Oncology convened an Expert Panel to conduct a systematic review of evidence from 2008 through 2015 to create recommendations informed by that evidence. Outcomes of interest included sequencing of hormonal agents, hormonal agents compared with chemotherapy, targeted biologic therapy, and treatment of premenopausal women. This guideline puts forth recommendations for endocrine therapy as treatment for women with HR-positive MBC.

RECOMMENDATIONS

Sequential hormone therapy is the preferential treatment for most women with HR-positive MBC. Except in cases of immediately life-threatening disease, hormone therapy, alone or in combination, should be used as initial treatment. Patients whose tumors express any level of hormone receptors should be offered hormone therapy. Treatment recommendations should be based on type of adjuvant treatment, disease-free interval, and organ function. Tumor markers should not be the sole criteria for determining tumor progression; use of additional biomarkers remains experimental. Assessment of menopausal status is critical; ovarian suppression or ablation should be included in premenopausal women. For postmenopausal women, aromatase inhibitors (AIs) are the preferred first-line endocrine therapy, with or without the cyclin-dependent kinase inhibitor palbociclib. As second-line therapy, fulvestrant should be administered at 500 mg with a loading schedule and may be administered with palbociclib. The mammalian target of rapamycin inhibitor everolimus may be administered with exemestane to postmenopausal women with MBC whose disease progresses while receiving nonsteroidal AIs. Among patients with HR-positive, human epidermal growth factor receptor 2-positive MBC, human epidermal growth factor receptor 2-targeted therapy plus an AI can be effective for those who are not chemotherapy candidates.