NCCN Guidelines® Insights: Breast Cancer, Version 4.2023.

The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Breast Cancer address all aspects of management for breast cancer. The treatment landscape of metastatic breast cancer is evolving constantly. The therapeutic strategy takes into consideration tumor biology, biomarkers, and other clinical factors. Due to the growing number of treatment options, if one option fails, there is usually another line of therapy available, providing meaningful improvements in survival. This NCCN Guidelines Insights report focuses on recent updates specific to systemic therapy recommendations for patients with stage IV (M1) disease.

BAF155 methylation drives metastasis by hijacking super-enhancers and subverting anti-tumor immunity.

Subunits of the chromatin remodeler SWI/SNF are the most frequently disrupted genes in cancer. However, how post-translational modifications (PTM) of SWI/SNF subunits elicit epigenetic dysfunction remains unknown. Arginine-methylation of BAF155 by coactivator-associated arginine methyltransferase 1 (CARM1) promotes triple-negative breast cancer (TNBC) metastasis. Herein, we discovered the dual roles of methylated-BAF155 (me-BAF155) in promoting tumor metastasis: activation of super-enhancer-addicted oncogenes by recruiting BRD4, and repression of interferon α/γ pathway genes to suppress host immune response. Pharmacological inhibition of CARM1 and BAF155 methylation not only abrogated the expression of an array of oncogenes, but also boosted host immune responses by enhancing the activity and tumor infiltration of cytotoxic T cells. Moreover, strong me-BAF155 staining was detected in circulating tumor cells from metastatic cancer patients. Despite low cytotoxicity, CARM1 inhibitors strongly inhibited TNBC cell migration in vitro, and growth and metastasis in vivo. These findings illustrate a unique mechanism of arginine methylation of a SWI/SNF subunit that drives epigenetic dysregulation, and establishes me-BAF155 as a therapeutic target to enhance immunotherapy efficacy.

Breast Cancer, Version 3.2022, NCCN Clinical Practice Guidelines in Oncology.

The therapeutic options for patients with noninvasive or invasive breast cancer are complex and varied. These NCCN Clinical Practice Guidelines for Breast Cancer include recommendations for clinical management of patients with carcinoma in situ, invasive breast cancer, Paget disease, phyllodes tumor, inflammatory breast cancer, and management of breast cancer during pregnancy. The content featured in this issue focuses on the recommendations for overall management of ductal carcinoma in situ and the workup and locoregional management of early stage invasive breast cancer. For the full version of the NCCN Guidelines for Breast Cancer, visit NCCN.org.

Results from a prospective longitudinal survey of employment and work outcomes in newly diagnosed cancer patients during and after curative-intent chemotherapy: A Wisconsin Oncology Network study.

BACKGROUND: Postcancer work limitations may affect a substantial proportion of patients and contribute to the "financial toxicity" of cancer treatment. The degree and nature of work limitations and employment outcomes are poorly understood for cancer patients, particularly in the immediate period of transition after active treatment. We prospectively examined employment, work ability, and work limitations during and after treatment. METHODS: A total of 120 patients receiving curative therapy who were employed prior to their cancer diagnosis and who intended to work during or after end of treatment (EOT) completed surveys at baseline (pretreatment), EOT, and 3, 6, and 12 months after EOT. Surveys included measures of employment, work ability, and work limitations. Descriptive statistics (frequencies, percentages, means with standard deviations) were calculated. RESULTS: A total of 111 participants completed the baseline survey. On average, participants were 48 years of age and were mostly white (95%) and female (82%) with a diagnosis of breast cancer (69%). Full-time employment decreased during therapy (from 88% to 50%) and returned to near prediagnosis levels by 12-month follow-up (78%). Work-related productivity loss due to health was high during treatment. CONCLUSIONS: This study is the first to report the effects of curative intent cancer therapy on employment, work ability, and work limitations both during and after treatment. Perceived work ability was generally high overall 12 months after EOT, although a minority reported persistent difficulty. A prospective analysis of factors (eg, job type, education, symptoms) most associated with work limitations is underway to assist in identifying at-risk patients.

Genetic/Familial High-Risk Assessment: Breast, Ovarian, and Pancreatic, Version 2.2021, NCCN Clinical Practice Guidelines in Oncology.

The NCCN Guidelines for Genetic/Familial High-Risk Assessment: Breast, Ovarian, and Pancreatic focus primarily on assessment of pathogenic or likely pathogenic variants associated with increased risk of breast, ovarian, and pancreatic cancer and recommended approaches to genetic testing/counseling and management strategies in individuals with these pathogenic or likely pathogenic variants. This manuscript focuses on cancer risk and risk management for BRCA-related breast/ovarian cancer syndrome and Li-Fraumeni syndrome. Carriers of a BRCA1/2 pathogenic or likely pathogenic variant have an excessive risk for both breast and ovarian cancer that warrants consideration of more intensive screening and preventive strategies. There is also evidence that risks of prostate cancer and pancreatic cancer are elevated in these carriers. Li-Fraumeni syndrome is a highly penetrant cancer syndrome associated with a high lifetime risk for cancer, including soft tissue sarcomas, osteosarcomas, premenopausal breast cancer, colon cancer, gastric cancer, adrenocortical carcinoma, and brain tumors.

NCCN Guidelines® Insights: Breast Cancer, Version 4.2021.

The NCCN Guidelines for Breast Cancer include up-to-date guidelines for clinical management of patients with carcinoma in situ, invasive breast cancer, Paget disease, phyllodes tumor, inflammatory breast cancer, male breast cancer, and breast cancer during pregnancy. These guidelines are developed by a multidisciplinary panel of representatives from NCCN Member Institutions with breast cancer-focused expertise in the fields of medical oncology, surgical oncology, radiation oncology, pathology, reconstructive surgery, and patient advocacy. These NCCN Guidelines Insights focus on the most recent updates to recommendations for adjuvant systemic therapy in patients with nonmetastatic, early-stage, hormone receptor-positive, HER2-negative breast cancer.

NCCN Guidelines Insights: Genetic/Familial High-Risk Assessment: Breast, Ovarian, and Pancreatic, Version 1.2020.

The NCCN Guidelines for Genetic/Familial High-Risk Assessment: Breast, Ovarian, and Pancreatic provide recommendations for genetic testing and counseling for hereditary cancer syndromes, and risk management recommendations for patients who are diagnosed with syndromes associated with an increased risk of these cancers. The NCCN panel meets at least annually to review comments, examine relevant new data, and reevaluate and update recommendations. These NCCN Guidelines Insights summarize the panel's discussion and most recent recommendations regarding criteria for high-penetrance genes associated with breast and ovarian cancer beyond BRCA1/2, pancreas screening and genes associated with pancreatic cancer, genetic testing for the purpose of systemic therapy decision-making, and testing for people with Ashkenazi Jewish ancestry.

Advances in the Treatment of Early-Stage HER2-Positive Breast Cancer.

The management of early-stage human epidermal growth factor receptor 2-positive (HER2+) breast cancer has evolved in recent years, with the current standard being to tailor the intensity of adjuvant treatment to individual risk. Risk-adapted approaches to systemic therapy have been facilitated both by the recent introduction of multiple novel HER2-targeted therapies and by the development of clinical and pathologic surrogates to enable better prediction of disease behavior. These approaches have been successful at both ends of the disease spectrum. Patients with low-risk tumors now experience excellent long-term outcomes and reduced toxicity after de-escalated adjuvant therapy, and patients with high-risk residual disease after neoadjuvant systemic therapy have had a significant decrease in the risk for disease recurrence with the escalation of adjuvant therapy, including the use of trastuzumab emtansine (also known as T-DM1). We review here key developments in neoadjuvant and adjuvant systemic therapy for early-stage HER2+ breast cancer and provide an overview of the current standards of management, incorporating recent advances in escalation and de-escalation approaches for higher- and lower-risk disease, respectively. We also discuss areas of ongoing clinical uncertainty, including how disease heterogeneity and hormone receptor status affect the selection of treatments and the selection of patients for chemotherapy-free approaches. Finally, we review ongoing areas of active investigation and unmet clinical needs in this patient population.

A randomized trial of immediate versus delayed survivorship care plan receipt on patient satisfaction and knowledge of diagnosis and treatment.

BACKGROUND: Survivorship care plans (SCPs) and care-planning sessions have been recommended for over a decade, yet evidence for their benefit remains mixed. In a randomized trial, changes in survivor knowledge and satisfaction before and after the receipt of an SCP were assessed. METHODS: Patients with breast cancer who had completed curative-intent treatment were randomized to immediate versus delayed receipt of an individualized SCP. All participants completed the modified Wisconsin Survey of Cancer Diagnosis and Management in Breast Cancer and the Preparing for Life As a New Survivor survey to assess individual knowledge about cancer diagnosis, treatment, side effects, and follow-up as well as satisfaction with communication and care coordination. Surveys were completed at baseline, at 4 weeks (before delayed receipt), and again at 12 weeks (after all participants had received SCPs); the primary outcome was change in knowledge at 4 weeks. RESULTS: In total, 127 eligible women were randomized. An improvement in individual knowledge was observed between baseline and week 12 for both arms combined (+1.6; 95% confidence interval, 0.9-2.3; P < .001). There was no statistically significant difference in the change in knowledge from baseline through week 4 between the arms. No significant change occurred for satisfaction scores over time. CONCLUSIONS: This randomized trial of immediate versus delayed SCP receipt demonstrated a small improvement (4%) in survivor knowledge. However, this improvement did not appear to be related to SCP provision. The authors hypothesized that the improvement was because of repeated administration of the knowledge survey. If improved survivor knowledge is a goal, then strategies beyond the 1-time provision and review of an SCP should be explored.

BRCA Mutation Carriers: Breast and Ovarian Cancer Screening Guidelines and Imaging Considerations.

Patients who carry the BRCA1 and BRCA2 gene mutations have an underlying genetic predisposition for breast and ovarian cancers. These deleterious genetic mutations are the most common genes implicated in hereditary breast and ovarian cancers. This monograph summarizes the evidence behind current screening recommendations, reviews imaging protocols specific to this patient population, and illustrates some of the imaging nuances of breast and ovarian cancers in this clinical setting.

The Presence of Cyclooxygenase 2, Tumor-Associated Macrophages, and Collagen Alignment as Prognostic Markers for Invasive Breast Carcinoma Patients.

Inflammation, and the organization of collagen in the breast tumor microenvironment, is an important mediator of breast tumor progression. However, a direct link between markers of inflammation, collagen organization, and patient outcome has yet to be established. A tumor microarray of 371 invasive breast carcinoma biopsy specimens was analyzed for expression of inflammatory markers, including cyclooxygenase 2 (COX-2), macrophages, and several collagen features in the tumor nest (TN) or the tumor-associated stroma (TS). The tumor microarray cohort included females, aged 18 to 80 years, with a median follow-up of 8.4 years. High expression of COX-2 (TN), CD68 (TS), and CD163 (TN and TS) predicted worse patient overall survival (OS). This notion was strengthened by the finding from the multivariate analysis that high numbers of CD163+ macrophages in the TS is an independent prognostic factor. Overall collagen deposition was associated with high stromal expression of COX-2 and CD163; however, total collagen deposition was not a predictor for OS. Conversely, local collagen density, alignment and perpendicular alignment to the tumor boundary (tumor-associated collagen signature-3) were predictors of OS. These results suggest that in invasive carcinoma, the localization of inflammatory cells and aligned collagen orientation predict poor patient survival. Additional clinical studies may help validate whether therapy with selective COX-2 inhibitors alters expression of CD68 and CD163 inflammatory markers.

PARP inhibitors in breast cancer: Bringing synthetic lethality to the bedside.

Individuals with breast and ovarian cancer susceptibility gene 1 (BRCA1) or BRCA2 germline mutations have a significantly increased lifetime risk for breast and ovarian cancers. BRCA-mutant cancer cells have abnormal homologous recombination (HR) repair of DNA. In these tumors, the base excision repair (BER) pathway is important for cell survival. The poly(adenosine diphosphate-ribose) polymerase (PARP) enzymes play a key role in BER, and PARP inhibitors are effective in causing cell death in BRCA-mutant cells while sparing normal cells-a concept called synthetic lethality. PARP inhibitors are the first cancer therapeutics designed to exploit synthetic lethality. Recent clinical trials in BRCA-mutant, metastatic breast cancer demonstrated improved outcomes with single-agent PARP inhibitors (olaparib and talazoparib) over chemotherapy. However, resistance to PARP inhibitors remains a challenge. Primarily due to myelosuppression, the combination of PARP inhibitors with chemotherapy has been difficult. Novel combinations with chemotherapy, immunotherapy, and other targeted therapies are being pursued. In this review, the authors discuss current knowledge of PARP inhibitors in BRCA-mutant breast cancer and potential future directions for these agents. Cancer 2018;124:2498-506. © 2018 American Cancer Society.

Assessment of adherence and relative dose intensity with oral chemotherapy in oncology clinical trials at an academic medical center.

Background/Aims Oral chemotherapy is increasingly utilized leaving the patient responsible for self-administering an often complex regimen where adverse effects are common. Non-adherence and reduced relative dose intensity are both associated with poorer outcomes in the community setting but are rarely reported in clinical trials. The purpose of this study is to quantify adherence and relative dose intensity in oncology clinical trials and to determine patient and study related factors that influence adherence and relative dose intensity. Methods Patients were identified from non-industry-funded clinical trials conducted between 1 January 2009 and 31 March 2013 at the University of Wisconsin Carbone Cancer Center. Data were extracted from primary research records. Descriptive statistics and linear regression modeling was performed using SAS 9.4. Results A total of 17 clinical trials and 266 subjects were included. Mean adherence was greater than 97% for the first eight cycles. Mean relative dose intensity was less than 90% for the first cycle and declined over time. Male gender, a performance status of 1 or 2, metastatic disease, and traveling more than 90 miles to reach the cancer center were associated with higher relative dose intensity. Conclusions Patients with cancer enrolled in clinical trials are highly adherent but unlikely to achieve protocol specified relative dose intensity. Given that determining the phase II dose is the primary endpoint of phase I trials, incorporating relative dose intensity into this determination should be considered.

Phase 1b study of orteronel in postmenopausal women with hormone-receptor positive (HR+) metastatic breast cancer.

Introduction Suppressing both androgens and estrogens may circumvent hormone receptor resistance in breast cancer by reducing androgen receptor stimulation. Selective inhibition of the 17, 20-lyase enzyme by orteronel leads to decreased androgen production in men and would be anticipated to reduce estrogen and androgen production in women. Thus, we conducted a phase 1b study of orteronel in postmenopausal women with hormone-receptor positive (HR+) metastatic breast cancer. Methods The primary objective was to identify the recommended phase 2 dose (R2PD) of orteronel in women; escalation was via standard 3 + 3 design. The initial dose was 300 mg BID and escalated to 400 mg BID. Cycle length was 28 days. Enrolled patients had HR+ metastatic breast cancer and were evaluated every 8 weeks for disease progression. Results Eight heavily pre-treated women enrolled [median age: 57 yo (range 47-73)]. Four received 300 mg BID at dose level 1; 4 received 400 mg BID at dose level 2. No dose limiting toxicities (DLTs) were observed. Adverse events (AE) at least possibly related to orteronel included grade 1-2 nausea (n = 4) and bone pain (n = 3), and grade 1 hypokalemia, hot flashes, myalgia and AST elevation (n = 2). The only grade 3 AE was hypertension (n = 2) with 8 patients receiving 34 cycles of treatment. No objective responses were seen; clinical benefit was seen in 2 patients with stable disease for more than 6 months. Serum estrogens and testosterone were suppressed from baseline on both doses of orteronel. Conclusions Orteronel 400 mg BID is well tolerated in postmenopausal women, and significantly suppresses serum estrogens and testosterone. Clinical benefit was seen among heavily pretreated postmenopausal women with HR+ metastatic breast cancer.

A phase I study of tivantinib in combination with temsirolimus in patients with advanced solid tumors.

Background A wide variety of human cancers exhibit dysregulated c-Met activity that has implications in oncogenesis. Phosphorylation of c-Met results in activation of the PI3K/AKT/mTOR pathway. Combined blockade of c-Met and mTOR pathways has shown efficacy in preclinical studies. Tivantinib is a c-Met inhibitor and temsirolimus is a selective mTOR inhibitor. We aimed to determine the maximum tolerated dose (MTD) and the recommended phase II dose (RP2D), dose-limiting toxicities (DLT), adverse events (AEs), clinical activity and pharmacokinetic (PK) parameters of the combination. Methods This open-label phase I study used a 3 + 3 dose escalation design. Patients (pts) were treated with escalating doses of tivantinib (120-360 mg tablets orally twice daily) and temsirolimus (20 mg IV weekly) followed by dose expansion at the MTD. Separate cohorts were planned for extensive (normal) and poor tivantinib metabolizers based on CYP2C19 genotypes. Cycles were 28 days besides cycle 1 that was 35 days to allow for PK analysis. Results Twenty-nine pts. [median age 58 (range 28-77)] were enrolled (21 in dose escalation and 8 in dose expansion). All were extensive CYP2C19 metabolizers. The most common types of cancer were colorectal, ovarian and non-small cell lung. Sixteen out of 21 and 6 out of 8 pts. were evaluable for DLT evaluation per protocol in the dose escalation and dose expansion phases, respectively. Pts remained on study for a median of 71 days (range 18-296). The MTD and RP2D was tivantinib 240 mg twice daily and temsirolimus 20 mg weekly. DLTs included grade (gr) 4 neutropenia (2 pts.; 1 with gr 3 febrile neutropenia), gr 3 abdominal pain (1 pt) and gr 2 mucositis resulting in inadequate drug delivery. The most common treatment related AEs grade ≥ 2 included: anemia (gr 2 in 9 pts., gr 3 in 3 pts), fatigue (gr 2 in 10 pts), anorexia (gr 2 in 9 pts), hypoalbuminemia (gr 2 in 6 pts., gr 3 in 2 pts), hypophosphatemia (gr 2 in 2 pts., gr 3 in 5 pts) and nausea (gr 2 in 6 pts., gr 3 in 1 pt). One pt. with ovarian cancer had a confirmed partial response and remained on study for 10 months, a second patient with ovarian cancer had stable disease and remained on study for 6 months and a third pt. with squamous cell carcinoma of the tongue had stable disease and remained on study for 7 months. Pharmacokinetic analysis showed that there is no interaction in the plasma concentrations between tivantinib and temsirolimus. Conclusions The combination of tivantinib with temsirolimus appears to be well tolerated with evidence of clinical activity.

Two Isoforms of the RNA Binding Protein, Coding Region Determinant-binding Protein (CRD-BP/IGF2BP1), Are Expressed in Breast Epithelium and Support Clonogenic Growth of Breast Tumor Cells.

CRD-BP/IGF2BP1 has been characterized as an "oncofetal" RNA binding protein typically highly expressed in embryonic tissues, suppressed in normal adult tissues, but induced in many tumor types. In this study, we show that adult breast tissues express ubiquitous but low levels of CRD-BP protein and mRNA. Although CRD-BP mRNA expression is induced in breast tumor cells, levels remain ∼1000-fold lower than in embryonic tissues. Despite low expression levels, CRD-BP is required for clonogenic growth of breast cancer cells. We reveal that because the most common protein isoform in normal adult breast and breast tumors has an N-terminal deletion (lacking two RNA recognition motif (RRM) domains) and is therefore missing antibody epitopes, CRD-BP expression has been under-reported by previous studies. We show that a CRD-BP mutant mouse strain retains expression of the shorter transcript (ΔN-CRD-BP), which originates in intron 2, suggesting that the impact of complete ablation of this gene in mice is not yet known. Either the full-length CRD-BP or the N-terminally truncated version can rescue the clonogenicity of CRD-BP knockdown breast cancer cells, suggesting that clonogenic function is served by either CRD-BP isoform. In summary, although CRD-BP expression levels are low in breast cancer cells, this protein is necessary for clonogenic activity.

Role of the androgen receptor in triple-negative breast cancer.

Triple-negative breast cancer (TNBC) is an aggressive disease with outcomes inferior to those of other breast cancer subtypes. No targeted therapies are currently approved for TNBC, and newer treatment approaches are critically needed. It is increasingly recognized that TNBC is a heterogeneous disease, and the role of androgen signaling in a subset of TNBC is emerging. Although the degree of androgen receptor (AR) expression in TNBC varies widely depending on the assay methodology, cutoff for positivity, and patient population, existing evidence suggests an association between a higher level of AR expression and improved outcomes. Despite lower pathologic complete response (pCR) rates with neoadjuvant therapy, patients with AR-dependent TNBCs have a better prognosis than those with TNBCs that are not AR-dependent. Furthermore, gene expression profiling has been used to identify a luminal androgen receptor subtype of TNBC that is dependent on AR signaling. Early clinical studies investigating agents targeting AR in advanced TNBC have produced promising results. We review herein the literature on the biology of AR in breast cancer and its prognostic and predictive role in TNBC, and we describe the results of early clinical trials with antiandrogens in this population. We also present our vision of the future development of newer therapeutic strategies in AR-dependent TNBC.

Management of patients with HER2-positive metastatic breast cancer: is there an optimal sequence of HER2-directed approaches?

The successful development of therapies targeting the human epidermal growth factor receptor 2 (HER2) has altered the natural progression of disease among patients with HER2-positive metastatic breast cancer. The monoclonal antibody trastuzumab was the first HER2-directed agent and it was associated with significantly improved outcomes for patients. Subsequently, other HER2-directed agents such as the monoclonal antibody pertuzumab, the tyrosine kinase receptor inhibitor lapatinib, and the immunoconjugate trastuzumab emtansine were developed to overcome resistance to trastuzumab and provide additional treatment options for patients. Recent data have demonstrated that the use of these HER2-directed agents improves outcomes. However, with the emergence of new HER2-targeted agents, the optimal sequencing of treatment remains unclear. Ongoing research is investigating new HER2 combinations, the role of sequencing, novel HER2-directed agents, and combinations with other targeted agents to overcome resistance.