Skeletal adverse effects with aromatase inhibitors in early breast cancer: evidence to date and clinical guidance

Adherence to Oral Anticancer Medications Among Women With Breast Cancer in Africa: A Scoping Review

PURPOSE

Oral anticancer medications (OAMs) improve treatment outcomes and survival in women with breast cancer (BC). However, adherence to OAM therapy remains suboptimal. This scoping review provides evidence of adherence to OAMs among African women with BC.

METHODS

We searched four databases and gray literature, using guidance from the Joanna Briggs Institute. Thirteen studies on adherence rates, determinants, and interventions were included. NVivo 12 software was used to perform thematic analysis of the included studies. The determinants (barriers and facilitators) associated with adherence were analyzed according to the five dimensions of the WHO multidimensional adherence model.

RESULTS

Most studies (n = 11, 85%) focused on endocrine medication. Depending on the definition, measurements, and assessment period, the nonadherence rates ranged from 4.3% to 65.4% for endocrine medications, 80.9% for cytotoxic chemotherapies, and 32.7% for combined medications. The significant barriers associated with adherence include Islamic religion, concurrent comorbidities, mastectomy, anastrozole treatment, side effects, unawareness of treatment insurance coverage, and seeking treatment from traditional healers. Thorough therapeutic communication regarding treatment, neoadjuvant chemotherapy, and adequate social support significantly facilitate adherence. A randomized controlled trial of breast nursing interventions reported improved patient adherence.

CONCLUSION

The evidence mapped from studies that evaluated OAM adherence in women with BC indicates that nonadherence to OAMs is common. Applying context-specific standardized measures to assess adherence and facilitators or strategies targeting the identified barriers can optimize adherence and treatment outcomes. Effective interventions to improve adherence are limited. Therefore, further empirical and interventional studies in Africa are required to enhance the evidence.

Adjuvant tamoxifen switched to exemestane treatment in postmenopausal women with estrogen receptor-positive early breast cancer: A pragmatic, multicenter, and prospective clinical trial in China

Objective

This post-approval safety study assessed the efficacy and safety of exemestane after 2-3 years of tamoxifen treatment among postmenopausal women with estrogen receptor-positive (ER+) early breast cancer in China.

Methods

Enrolled patients had received 2-3 years of tamoxifen and were then switched to exemestane for completion of 5 consecutive years of adjuvant endocrine therapy. The primary endpoint was the time from enrollment to the first occurrence of locoregional/distant recurrence of the primary breast cancer, appearance of a second primary or contralateral breast cancer, or death due to any cause. Other endpoints included the proportion of patients experiencing each event, incidence rate per annum, relationships between human epidermal growth factor receptor 2 status and time to event, and relationship between disease history variables and time to event.

Results

Overall, 558 patients were included in the full analysis set: 397 (71.1%) completed the study, 20 experienced an event, and 141 discontinued [47 owing to an adverse event (AE); 37 no longer willing to participate]. Median duration of treatment was 29.5 (range, 0.1-57.7) months. Median time to event was not reached. Event-free survival probability at 36 months was 91.4% (95% CI, 87.7%-95.1%). The event incidence over the total exposure time of exemestane therapy was 3.5 events/100 person-years (20/565). Multivariate analysis showed an association between tumor, lymph node, and metastasis stage at initial diagnosis and time to event [hazard ratio: 1.532 (95% CI, 1.129-2.080); P=0.006]. Most AEs were grade 1 or 2 in severity, with arthralgia (7.7%) being the most common treatment-related AE.

Conclusions

This study supports the efficacy and safety of exemestane in postmenopausal Chinese women with ER+ breast cancer previously treated with adjuvant tamoxifen for 2-3 years. No new safety signals were identified in the Chinese population.

Teaching cancer imaging in the era of precision medicine: Looking at the big picture

The role of imaging in cancer diagnosis and treatment has evolved at the same rapid pace as cancer management. Over the last twenty years, with the advancement of technology, oncology has become a multidisciplinary field that allows for researchers and clinicians not only to create individualized treatment options for cancer patients, but also to evaluate patients’ response to therapy with increasing precision. Familiarity with these concepts is a requisite for current and future radiologists, as cancer imaging studies represent a significant and growing component of any radiology practice, from tertiary cancer centers to community hospitals.

In this review we provide the framework to teach cancer imaging in the era of genomic oncology. After reading this article, readers should be able to illustrate the basics cancer genomics, modern cancer genomics, to summarize the types of systemic oncologic therapies available, their patterns of response and their adverse events, to discuss the role of imaging in oncologic clinical trials and the role of tumor response criteria and to display the future directions of oncologic imaging.

Genetic Underpinnings of Musculoskeletal Pain During Treatment With Aromatase Inhibitors for Breast Cancer: A Biological Pathway Analysis

BACKGROUND

Musculoskeletal pain (MSKP) is the most reported symptom during treatment with aromatase inhibitors (AIs) for breast cancer. The mechanisms underlying MSKP are multidimensional and not well understood. The goals of this biological pathway analysis were to (1) gain an understanding of the genetic variation and biological mechanisms underlying MSKP with AI therapy and (2) identify plausible biological pathways and candidate genes for future investigation.

METHOD

Genes associated with MSKP during AI therapy or genes involved in drug metabolism of and response to AIs were identified from the literature. Studies published through February 2019 were queried in PubMed®. The genes identified from the literature were entered into QIAGEN's Ingenuity® Pathway Analysis (IPA) software to generate canonical pathways, upstream regulators, and networks through a core analysis.

RESULTS

The 17 genes identified were ABCB1, ABCG1, CYP17A1, CYP19A1, CYP27B1, CYP2A6, CYP3A4, CYP3A5, ESR1, OATP1B1, OPG, RANKL, SLCO3A1, TCL1A, UGT2A1, UGT2B17, and VDR. These genes are involved in encoding bone-remodeling regulators, drug-metabolizing enzymes (cytochrome P450 family, UDP-glucuronosyltransferases family), or drug transporters (ATP-binding cassette transporters, organic anion transporters). Multiple plausible biological pathways (e.g., nicotine degradation, melatonin degradation) and candidate genes (e.g., NFKB, HSP90, AKT, ERK1/2, FOXA2) are proposed for future investigation based on the IPA results.

CONCLUSION

Multiple genes and molecular-level etiologies may contribute to MSKP with AI therapy in women with breast cancer. Our innovative combination of gene identification from the literature plus biological pathway analysis allowed for the emergence of novel candidate genes and biological pathways for future investigations.

Clinical and genetic risk factors for aromatase inhibitor-associated arthralgia in breast cancer survivors

BACKGROUND

Arthralgia is a common and debilitating toxicity of aromatase inhibitors (AI) that leads to premature drug discontinuation. We sought to evaluate the clinical and genetic risk factors associated with AI-associated arthralgia (AIAA).

METHODS

We performed a cross-sectional study among postmenopausal women with stage 0-III breast cancer who were prescribed a third-generation AI for adjuvant therapy. The primary outcome was patient-reported AIAA occurrence. We extracted and assayed germline DNA for single nucleotide polymorphisms (SNPs) of genes implicated in estrogen and inflammation pathways. Multivariable logistic regression models examined the association between demographic, clinical, and genetic factors and AIAA. Analyses were restricted to White participants.

RESULTS

Among 1049 White participants, 543 (52%) reported AIAA. In multivariable analyses, women who had a college education [Adjusted Odds Ratio (AOR) 1.49, 95% Confidence Interval (CI) 1.00-2.20], had a more recent transition into menopause (<10 years) (5-10 years AOR 1.55, 95% CI 1.09-2.22; <5 years AOR 1.78, 95% CI 1.18-2.67), were within one year of starting AIs (AOR 1.61, 95% CI 1.08-2.40), and those who received chemotherapy (AOR 1.38, 95% CI 1.02-1.88) were significantly more likely to report AIAA. Additionally, SNP rs11648233 (HSD17B2) was significantly associated with higher odds of AIAA (AOR 2.21, 95% CI 1.55-3.16).

CONCLUSIONS

Time since menopause and start of AIs, prior chemotherapy, and SNP rs11648233 within the HSD17B2 gene in the estrogen pathway were significantly associated with patient-reported AIAA. These findings suggest that clinical and genetic factors involved in estrogen withdrawal increase the risk of AIAA in postmenopausal breast cancer survivors.

Current Applications of Nanoemulsions in Cancer Therapeutics

Nanoemulsions are pharmaceutical formulations composed of particles within a nanometer range. They possess the capacity to encapsulate drugs that are poorly water soluble due to their hydrophobic core nature. Additionally, they are also composed of safe gradient excipients, which makes them a stable and safe option to deliver drugs. Cancer therapy has been an issue for several decades. Drugs developed to treat this disease are not always successful or end up failing, mainly due to low solubility, multidrug resistance (MDR), and unspecific toxicity. Nanoemulsions might be the solution to achieve efficient and safe tumor treatment. These formulations not only solve water-solubility problems but also provide specific targeting to cancer cells and might even be designed to overcome MDR. Nanoemulsions can be modified using ligands of different natures to target components present in tumor cells surface or to escape MDR mechanisms. Multifunctional nanoemulsions are being studied by a wide variety of researchers in different research areas mainly for the treatment of different types of cancer. All of these studies demonstrate that nanoemulsions are efficiently taken by the tumoral cells, reduce tumor growth, eliminate toxicity to healthy cells, and decrease migration of cancer cells to other organs.

Baseline bone health status in multi-ethnic South African postmenopausal breast cancer patients at initiation of aromatase inhibitor therapy: A descriptive study

Introduction

Osteoporosis (OP) risk factor assessment and bone mineral density (BMD) testing are frequently omitted at baseline in aromatase inhibitor (AI) studies, which may lead to misinterpretation of AI associated bone loss. The present study describes bone health of South African postmenopausal women of predominantly Mixed Ancestry, prior to AI treatment.

Methods

This descriptive baseline study, nested in a prospective AI cohort study, included postmenopausal women with endocrine sensitive breast cancer, aged 50 to 80 years. A baseline questionnaire documented demographic-, medical-, lifestyle- and fracture history. Body weight was assessed clinically, and body composition and BMD measured via dual energy absorptiometry (DXA). Data was analysed in STATA 14 using descriptive and inferential statistics.

Results

101 participants were recruited, with a mean age of 61±7 years. Nearly a third (n = 32) of women at baseline fulfilled global criteria for bone protection (BMD T-score ≥-2SD (n = 18); BMD T-score -1.5SD to < -2SD with risk factors (n = 14). Lower body weight, body mass index (BMI), fat mass index and lean mass index were significantly associated with the participants with a BMD measurement in keeping with a diagnosis of OP (p <0.001). Low vitamin D was present in 93% of the cohort tested (n = 95), whilst deficient vitamin D status (<20ng/ml) was documented in 52 women (55%).

Conclusions

In this study, a third of postmenopausal women considered for AI therapy fulfilled international criteria for bone protective pharmacological intervention. This emphasizes the need for clinical risk and BMD assessment in postmenopausal breast cancer patients at baseline. Body composition and bone health associations highlight bone fragility associated with lower body weight.

Impact of an osteoporosis specialized unit on bone health in breast cancer survivals treated with aromatase inhibitors

OBJECTIVE

Considering the increased fracture risk in early breast cancer patients treated with aromatase inhibitors (AI), we assessed the impact of a preventive intervention conducted by a specialized osteoporosis unit on bone health at AI treatment start.

MATERIAL AND METHODS

Retrospective cohort of postmenopausal women who started treatment with AI after breast cancer surgical/chemotherapy treatment and were referred to the osteoporosis unit for a comprehensive assessment of bone health. Bone densitometry and fracture screening by plain X-ray were performed at the baseline visit and once a year for 5 years.

RESULTS

The final record included 130 patients. At AI treatment start, 49% had at least one high-risk factor for fractures, 55% had osteopenia, and 39% osteoporosis. Based on the baseline assessment, 79% of patients initiated treatment with bisphosphonates, 88% with calcium, and 79% with vitamin D. After a median of 65 (50-77) months, 4% developed osteopenia or osteoporosis, and 14% improved their densitometric diagnosis. Fifteen fractures were recorded in 11 (8.5%) patients, all of them receiving preventive treatment (10 with bisphosphonates). During the follow-up period, patients with one or more high-risk factors for fracture showed a greater frequency of fractures (15% vs. 3%) and experienced the first fracture earlier than those without high-risk factors (mean of 99 and 102 months, respectively; P=0.023).

CONCLUSIONS

The preventive intervention of a specialized unit at the start of AI treatment in breast cancer survivors allows the identification of patients with high fracture risk and may contribute to preventing bone events in these patients.

Vitamin D Levels, Vitamin D Receptor Polymorphisms, and Inflammatory Cytokines in Aromatase Inhibitor-Induced Arthralgias: An Analysis of CCTG MA.27

BACKGROUND

Approximately half of women taking aromatase inhibitor (AI) therapy develop AI-induced arthralgia (AIA), and many might discontinue AI therapy because of the pain. Using plasma samples from the MA.27 study, we assessed several factors potentially associated with AIA.

PATIENTS AND METHODS

MA.27 is a phase III adjuvant trial comparing 2 AIs, exemestane versus anastrozole. Within an 893-participant nested case-control AIA genome-wide association study, we nested a 72 AIA case-144 control assessment of vitamin D plasma concentrations, corrected for seasonal and geographic variation. We also examined 9 baseline inflammatory cytokines: interleukin (IL)-1β, IL-6, tumor necrosis factor-α, interferon (IFN)γ, IL-10, IL-12p70, IL-17, IL-23, and chemokine ligand (CCL)-20. Finally, we analyzed the multivariate effects of baseline factors: vitamin D level, previously identified musculoskeletal single nucleotide polymorphisms, age, body mass index, and vitamin D receptor (VDR) Fok-I variant genotype on AIA development.

RESULTS

Changes in vitamin D from baseline to 6 months were not significantly different between cases and controls. Elevated inflammatory cytokine levels were not associated with development of AIA. The multivariate model included no clinical factors associated with AIA. However, women with the VDR Fok-I variant genotype were more likely to have a lower IL-1β level (P = .0091) and less likely to develop AIA after 6 months of AI compared with those with the wild type VDR (P < .0001).

CONCLUSION

In this nested case-control correlative study, vitamin D levels were not significantly associated with development of AIA; however, patients with the Fok-I VDR variant genotype were more likely to have a significant reduction in IL-1β level, and less likely to develop AIA.

Derivatives of alkyl gallate triphenylphosphonium exhibit antitumor activity in a syngeneic murine model of mammary adenocarcinoma

We previously demonstrated that alkyl gallates coupled to triphenylphosphine have a selective and efficient antiproliferative effect by inducing mitochondrial uncoupling in vitro due to the increased mitochondrial transmembrane potential of tumor cells. Therefore, in this work, the in vivo antitumor activities of alkyl gallate triphenylphosphonium derivatives (TPP+C8, TPP+C10 and TPP+C12) were evaluated in a syngeneic murine model of breast cancer. We found that TPP+C10 increased the cytosolic ADP/ATP ratio and significantly increased the AMP levels in a concentration-dependent manner in TA3/Ha murine mammary adenocarcinoma cells. Interestingly, TPP+C10 induced a decrease in the levels of cellular proliferation markers and promoted caspase-3 activation in tumor-bearing mice. Additionally, TPP+C10 inhibited tumor growth in the syngeneic mouse model. Importantly, 30days of intraperitoneal (i.p.) administration of the combination of TPP+C10 (10mg/kg/48h) and the antibiotic doxycycline (10mg/kg/24h) completely eliminated the subcutaneous tumor burden in mice (n=6), without any relapses at 60days post-treatment. This enhancement of the individual activities of TPP+C10 and doxycycline is due to the uncoupling of oxidative phosphorylation by TPP+C10 and the inhibition of mitochondrial biogenesis by doxycycline, as demonstrated by loss of mitochondrial mass and overexpression of PGC1-α as an adaptive response. Moreover, i.p. administration of TPP+C10 (10mg/kg/24h) to healthy mice did not produce toxicity or damage in organs important for drug metabolism and excretion, as indicated by hematological, biochemical and histological assessments. These findings suggest that the combination of TPP+C10 with doxycycline is a valuable candidate therapy for breast cancer management.

Pharmacogenetics and aromatase inhibitor induced side effects in breast cancer patients

This paper reviews genetic variations mainly related to the onset of adverse events during aromatase inhibitors in early breast cancer. Genetic variability could occur at different steps. The analysis included studies that involved breast cancer patients, treated with an aromatase inhibitor, genotyped for CYP19A1 and/or CYP17A1 and/or CYP27B1 and/or TCLA1, and/or RANK/RANKL/OPG and/or ESR1/ESR2, and assessed for toxicity profile. Twenty-two articles were included for the analysis. Three studies evaluated outcomes and adverse events; 19 studies assessed only side effects. Functional variations may be useful in predicting the onset of toxicities. The identification of polymorphisms at increased risk of toxicity may enable patient management. However, more data are needed to be applied in the individualization of treatment in daily practice.

Management of Aromatase Inhibitor-Associated Bone Loss (AIBL) in postmenopausal women with hormone sensitive breast cancer: Joint position statement of the IOF, CABS, ECTS, IEG, ESCEO IMS, and SIOG

BACKGROUND

Several guidelines have been reported for bone-directed treatment in women with early breast cancer (EBC) for averting fractures, particularly during aromatase inhibitor (AI) therapy. Recently, a number of studies on additional fracture related risk factors, new treatment options as well as real world studies demonstrating a much higher fracture rate than suggested by randomized clinical controlled trials (RCTs). Therefore, this updated algorithm was developed to better assess fracture risk and direct treatment as a position statement of several interdisciplinary cancer and bone societies involved in the management of AI-associated bone loss (AIBL).

PATIENTS AND METHODS

A systematic literature review identified recent advances in the management of AIBL. Results with individual agents were assessed based on trial design, size, follow-up, and safety.

RESULTS

Several fracture related risk factors in patients with EBC were identified. Although, the FRAX algorithm includes fracture risk factors (RF) in addition to BMD, it does not seem to adequately address the effects of AIBL. Several antiresorptive agents can prevent and treat AIBL. However, concerns regarding compliance and long-term safety remain. Overall, the evidence for fracture prevention is strongest for denosumab 60 mg s.c. every 6 months. Additionally, recent studies as well as an individual patient data meta-analysis of all available randomized trial data support additional anticancer benefits from adjuvant bisphosphonate treatment in postmenopausal women with a 34% relative risk reduction in bone metastasis and 17% relative risk decrease in breast cancer mortality that needs to be taken into account when advising on management of AIBL.

CONCLUSIONS

In all patients initiating AI treatment, fracture risk should be assessed and recommendation with regard to exercise and calcium/vitamin D supplementation given. Bone-directed therapy should be given to all patients with a T-score<-2.0 or with a T-score of <-1.5 SD with one additional RF, or with ≥2 risk factors (without BMD) for the duration of AI treatment. Patients with T-score>-1.5 SD and no risk factors should be managed based on BMD loss during the first year and the local guidelines for postmenopausal osteoporosis. Compliance should be regularly assessed as well as BMD on treatment after 12 - 24 months. Furthermore, because of the decreased incidence of bone recurrence and breast cancer specific mortality, adjuvant bisphosphonates are recommended for all postmenopausal women at significant risk of disease recurrence.

TBS and BMD at the end of AI-therapy: A prospective study of the B-ABLE cohort

INTRODUCTION

Patients with breast cancer under aromatase inhibitor (AI) treatment often develop osteoporosis and their average bone loss rate is twice that of natural reduction during menopause, increasing fracture risk. As the current diagnostic technique based on bone mineral density (BMD) provides no information on bone quality, the Trabecular Bone Score (TBS) has been proposed to reflect bone microarchitecture status. The present study was designed to assess prospective changes in TBS and lumbar spine (LS) BMD in postmenopausal women with breast cancer at completion of AI treatment.

METHODS

B-ABLE is a prospective cohort of 735 women with breast cancer treated with AIs according to American Society of Clinical Oncology recommendations: 5years of AI starting within 6weeks post-surgery or 1month after the last cycle of chemotherapy (5y-AI group), or switching to an AI to complete 5-year therapy after 2-3years of tamoxifen (pTMX-AI group). Patients with osteoporosis were treated with oral bisphosphonates (BP). TBS and LS-BMD changes at completion of AI therapy were evaluated by Student t-test for paired samples. Pearson correlation coefficients were computed for correlations between LS-BMD and TBS.

RESULTS

AI treatment was completed by 277 women. Of these, 70 (25.3%) were allocated to BP therapy. The non-BP-treated patients (74.7%) showed significant decreases in TBS (-2.94% in pTMX-AI and -2.93% in 5y-AI groups) and in LS-BMD (-4.14% in pTMX-AI and -2.28% in 5y-AI groups) at the end of AI treatment. In BP-treated patients, TBS remained stable at the end of AI treatment, whereas LS-BMD showed significant increases (+2.30% in pTMX-AI and +5.33% in 5y-AI groups). Moderate associations between TBS and LS-BMD values at baseline and at the end of AI treatment (r=0.4; P<0.001) were observed. At the end of treatment, changes in spine BMD and TBS were weakly correlated (r=0.1, P<0.01).

CONCLUSIONS

AI therapy induces significant decreases in TBS, comparable to BMD loss. BP-treated patients maintained TBS values, whereas BMD increased. AI treatment leads to deterioration of bone microarchitecture, which seems to be attenuated by BP therapy.

Molecular basis of aromatase inhibitor associated arthralgia: known and potential candidate genes and associated biomarkers

INTRODUCTION

Aromatase inhibitors (AIs) are routinely used for the adjuvant treatment of women with hormone receptor-positive early breast cancer. AIs are widely prescribed in the postmenopausal setting, as they are effective at preventing recurrence. However, their use is complicated by significant adverse effects, particularly arthralgia, noted in up to 50% of treated patients, and thereby affects quality of life and AI compliance. The mechanism by which AIs cause arthralgia is largely unknown, although there is a growing body of literature which suggests that there may be multiple intersecting mechanisms. Areas covered: This review describes the evidence for the mechanistic basis of AI arthralgia as well as potential pathways that could contribute to the development of AI associated arthralgia. Expert opinion: Interplay of multiple factors, such as interpatient variability in AI metabolism, possibly related to pharmacogenetic factors, the sudden decline of estrogen synthesis, vitamin D status, as well as upregulation of cytokines and inflammation pathways may precipitate or exacerbate muscle and joint pain are linked during AI therapy. However, much more research is needed in this area given the frequency and severity of AI-associated arthralgia.

Aromatase inhibitors induced autoimmune disorders in patients with breast cancer: A review

Subacute cutaneous lupus erythematosus (SCLE) is characterized by particular cutaneous manifestations such as non-scaring plaques mainly in sunlight exposed parts of the body along with specific serum autoantibodies (i.e. antinuclear antibodies (ANA), Ro/SSa, La/SSb). It is considered either idiopathic or drug induced. The role of chemotherapeutic agents in causing SCLE has been investigated with the taxanes being the most common anticancer agents. However, recent data emerging point toward antiestrogen therapies as a causative factor not only for SCLE but also for a variety of autoimmune disorders. This is a report of a case of a 42 year old woman who developed clinical manifestations of SCLE after letrozole treatment in whom remission of the cutaneous manifestations was noticed upon discontinuation of the drug. In addition, an extensive review of the English literature has been performed regarding the association of antiestrogen therapy with autoimmune disorders. In conclusion, Oncologists should be aware of the potential development of autoimmune reactions in breast cancer patients treated with aromatase inhibitors.