Identifying homologous recombination deficiency in breast cancer: genomic instability score distributions differ among breast cancer subtypes.

PURPOSE: A 3-biomarker homologous recombination deficiency (HRD) score is a key component of a currently FDA-approved companion diagnostic assay to identify HRD in patients with ovarian cancer using a threshold score of ≥ 42, though recent studies have explored the utility of a lower threshold (GIS ≥ 33). The present study evaluated whether the ovarian cancer thresholds may also be appropriate for major breast cancer subtypes by comparing the genomic instability score (GIS) distributions of BRCA1/2-deficient estrogen receptor-positive breast cancer (ER + BC) and triple-negative breast cancer (TNBC) to the GIS distribution of BRCA1/2-deficient ovarian cancer. METHODS: Ovarian cancer and breast cancer (ER + BC and TNBC) tumors from ten study cohorts were sequenced to identify pathogenic BRCA1/2 mutations, and GIS was calculated using a previously described algorithm. Pathologic complete response (pCR) to platinum therapy was evaluated in a subset of TNBC samples. For TNBC, a threshold was set and threshold validity was assessed relative to clinical outcomes. RESULTS: A total of 560 ovarian cancer, 805 ER + BC, and 443 TNBC tumors were included. Compared to ovarian cancer, the GIS distribution of BRCA1/2-deficient samples was shifted lower for ER + BC (p = 0.015), but not TNBC (p = 0.35). In the subset of TNBC samples, univariable logistic regression models revealed that GIS status using thresholds of ≥ 42 and ≥ 33 were significant predictors of response to platinum therapy. CONCLUSIONS: This study demonstrated that the GIS thresholds used for ovarian cancer may also be appropriate for TNBC, but not ER + BC. GIS thresholds in TNBC were validated using clinical response data to platinum therapy.

An open-label, pilot study of veliparib and lapatinib in patients with metastatic, triple-negative breast cancer.

BACKGROUND: Poly (ADP-ribose)-polymerase inhibitors (PARPi) have been approved for cancer patients with germline BRCA1/2 (gBRCA1/2) mutations, and efforts to expand the utility of PARPi beyond BRCA1/2 are ongoing. In preclinical models of triple-negative breast cancer (TNBC) with intact DNA repair, we have previously shown an induced synthetic lethality with combined EGFR inhibition and PARPi. Here, we report the safety and clinical activity of lapatinib and veliparib in patients with metastatic TNBC. METHODS: A first-in-human, pilot study of lapatinib and veliparib was conducted in metastatic TNBC (NCT02158507). The primary endpoint was safety and tolerability. Secondary endpoints were objective response rates and pharmacokinetic evaluation. Gene expression analysis of pre-treatment tumor biopsies was performed. Key eligibility included TNBC patients with measurable disease and prior anthracycline-based and taxane chemotherapy. Patients with gBRCA1/2 mutations were excluded. RESULTS: Twenty patients were enrolled, of which 17 were evaluable for response. The median number of prior therapies in the metastatic setting was 1 (range 0-2). Fifty percent of patients were Caucasian, 45% African-American, and 5% Hispanic. Of evaluable patients, 4 demonstrated a partial response and 2 had stable disease. There were no dose-limiting toxicities. Most AEs were limited to grade 1 or 2 and no drug-drug interactions noted. Exploratory gene expression analysis suggested baseline DNA repair pathway score was lower and baseline immunogenicity was higher in the responders compared to non-responders. CONCLUSIONS: Lapatinib plus veliparib therapy has a manageable safety profile and promising antitumor activity in advanced TNBC. Further investigation of dual therapy with EGFR inhibition and PARP inhibition is needed. TRIAL REGISTRATION: ClinicalTrials.gov , NCT02158507 . Registered on 12 September 2014.

Adjuvant cyclin-dependent kinase 4/6 inhibition in hormone receptor-positive breast cancer: One Monarch to rule them all?

The use of cyclin-dependent kinase 4/6 (CDK4/6) inhibitors has dramatically improved outcomes for patients with metastatic, hormone receptor (HR)-positive breast cancer. Because of the continued high rate of relapse in patients with node-positive, HR-positive disease, evaluating these agents in the adjuvant setting is the logical next step. Three adjuvant CDK inhibitor trials have been reported to date, with only 1 of them showing a statistical advantage for the CDK inhibitor in comparison with endocrine therapy alone. These trials have key similarities and differences that could explain the disparate results. The one positive trial has a relatively short follow-up, and continued analysis is critical to confirm the benefit of adjuvant CDK inhibition in this setting. It is imperative that predictive biomarkers be determined so that these agents can be used in the patients most likely to benefit and thus the additional toxicity and expense can be avoided in those who do not require these agents. LAY SUMMARY: There is a critical need for new agents to prevent relapse in patients with hormone receptor-positive breast cancer. Trials to date evaluating cyclin-dependent kinase inhibitors, which decrease how quickly cancer cells multiply, have shown mixed results, with only 1 trial demonstrating that these agents decrease recurrence.

Risk factors for bisphosphonate-associated osteonecrosis of the jaw in the prospective randomized trial of adjuvant bisphosphonates for early-stage breast cancer (SWOG 0307).

PURPOSE: Bisphosphonates reduce bone metastases in postmenopausal women with early-stage breast cancer but carry the risk of bisphosphonate-related osteonecrosis of the jaw (BRONJ). We describe risk factors for BRONJ and compare BRONJ provoked by infection or trauma with spontaneous lesions, which carry a better prognosis. METHODS: SWOG 0307 randomized women with stage I-III breast cancer to receive zoledronic acid (ZA), clodronate (CL), or ibandronate (IB) for 3 years, implemented BRONJ prevention guidelines, and collected information about dental health and development of BRONJ. All statistical tests were two-sided. RESULTS: Of 6018 women, 48 developed BRONJ. Infection was present in 21 (43.8%). Median time to BRONJ was 2.1 years for ZA, 2.0 years for IB, and 3.4 years for clodronate (p = 0.04). BRONJ was associated with bisphosphonate type (28/2231 (1.26%) for ZA, 8/2235 (0.36%) for CL, 12/1552 (0.77%) for IB), dental calculus (OR 2.03), gingivitis (OR 2.11), moderate/severe periodontal disease (OR 2.87), and periodontitis > 4 mm (OR 2.20) (p < 0.05). Of 57 lesions, BRONJ occurred spontaneously in 20 (35.1%) and was provoked by dental extraction in 20 (35.1%), periodontal disease in 14 (24.6%), denture trauma in 6 (10.5%), and dental surgery in 2 (3.5%). Spontaneous BRONJ occurred more frequently at the mylohyoid ridge. There were no differences in dental disease, infection, or bisphosphonate type between spontaneous and provoked BRONJ. CONCLUSION: ZA and worse dental health were associated with increased incidence of BRONJ, with a trend toward additive risk when combined. BRONJ incidence was lower than in similar studies, with prevention strategies likely linked to this. CLINICAL TRIAL NUMBER: NCT00127205 REGISTRATION DATE: July 2005.

PI3Kinase Inhibition in Hormone Receptor-Positive Breast Cancer.

Derangement of the phosphatidylinositol-3 kinase (PI3K) pathway is implicated in several subtypes of breast cancers. Mutation or upregulation of PI3K enhances cancer cells' survival, proliferation, and ability to metastasize, making it an attractive molecular target for systemic therapy. PI3K has four isoforms, and several drugs targeting individual isoforms or pan-PI3K have been or are currently being investigated in clinical trials. However, the search for an effective PI3K inhibitor with a robust therapeutic effect and reasonable safety profile for breast cancer treatment remains elusive. This review focuses on the recently completed and ongoing clinical trials involving PI3K inhibitors as mono- or combination therapy in breast cancer. We review the salient findings of clinical trials, the therapeutic efficacy of PI3K inhibitors, and reported adverse effects leading to treatment discontinuation. Lastly, we discuss the challenges and potential opportunities associated with adopting PI3K inhibitors in the clinic.

Impact of early dose intensity reduction of Palbociclib on clinical outcomes in patients with hormone-receptor-positive metastatic breast cancer.

BACKGROUND: Palbociclib is commonly added to an aromatase inhibitor (AI) as first-line therapy in ER + HER2- metastatic breast cancer (MBC). There are no data on the effect of the relative dose intensity (RDI) of palbociclib in first-line setting on clinical outcomes. The objective of this study is to explore the association of RDI and dose reduction of palbociclib in the first-line setting with PFS. METHODS: This is a retrospective study of ER + HER2- MBC patients who received palbociclib plus AI in first-line setting. Subjects ≥ 18 years old with MBC, who were started on palbociclib 125 mg daily, had completed ≥ 1 cycle of palbociclib, and did not progress within the first 12 weeks were eligible. Analyses were performed at 12- and 36-week landmarks (LM). RDI was defined as the total amount of palbociclib taken per the total amount planned. RDI-high-12 and RDI-low-12 cohorts were defined as patients receiving palbociclib with RDI ≥ 80% and RDI < 80% during the first 12 weeks, respectively. Reduction-12 and No-reduction-12 cohorts were defined as patients who had any dose reduction and patients who had no reduction during the first 12 weeks, respectively. RESULTS: 56 patients were eligible. Kaplan-Meier analysis from 12-week LM showed a median PFS of 17.1 months in RDI-high-12 versus 6.8 months in RDI-low-12 cohort (p = 0.0006). There was a 7.0-month improvement in median PFS in No-reduction-12 versus Reduction-12 cohort (p = 0.0638). Median PFS at 36-week LM was not reached in RDI-high-36 versus 8.6 months in RDI-low-36 cohort (p = 0.0703). CONCLUSIONS: RDI < 80% of palbociclib during the first 12 weeks, when used in combination with an AI in first-line setting in ER + HER2- MBC, is associated with significantly shorter PFS compared to RDI ≥ 80%. There is a trend towards shorter PFS among patients with RDI < 80% versus RDI ≥ 80% at 36 weeks. A larger study is needed to validate these findings.

Less Toxic Chemotherapy in Locally Advanced Breast Cancer.

OBJECTIVES: Preoperative chemotherapy produces tumor shrinkage in most patients with locally advanced breast cancer, including some pathological complete responses (pCRs). We attempted this using a much less toxic sequential regimen, given with concurrent bevacizumab. METHODS: Patients with locally advanced breast cancer received 3 intravenous doses each of preoperative sequential liposome encapsulated doxorubicin 25 mg/m2, paclitaxel 175 mg/m2, and cyclophosphamide 600 mg/m2, with concurrent bevacizumab every 2 weeks without growth factor support. RESULTS: Between March 2008 and December 2009, 32 patients received treatment. There was no cardiotoxicity, and other toxicity was mild (no grade 4 or 5 toxicity). No long-term toxicity, including cardiotoxicity, has been observed. Every patient had ≥30% reduction in tumor size; 9 of 31 patients who completed chemotherapy had pCR at operation. Seven years later, 22 of 32 patients remain free of recurrence and 27 of 32 are alive. CONCLUSIONS: The preoperative chemotherapy used appears to be comparably effective, but much less toxic than that used in most conventional regimens and should be studied further. Concurrent treatment with bevacizumab (reported separately) did not provide any additional benefit.

A Phase I/II study of suberoylanilide hydroxamic acid (SAHA) in combination with trastuzumab (Herceptin) in patients with advanced metastatic and/or local chest wall recurrent HER2-amplified breast cancer: a trial of the ECOG-ACRIN Cancer Research Group (E1104).

PURPOSE: Suberoylanilide hydroxamic acid (SAHA; vorinostat), a small molecule inhibitor of histone deacetylase, attenuates signaling pathways known to confer trastuzumab resistance. A combination of SAHA and trastuzumab may be a promising strategy to improve the efficacy of trastuzumab against breast cancer. In this Phase I/II study, we evaluated the toxicity and response rate after treatment with SAHA and trastuzumab in patients with HER2-overexpressing metastatic breast cancer with trastuzumab-resistant progressive disease. METHODS: In Phase I, the SAHA dose was modified in cohorts of 3-6 patients to find the dose level at which 0 or 1 patients experienced a dose-limiting toxicity (DLT) during the first cycle of therapy. In the Phase II study, response to the recommended dose identified in Phase I was based on the response evaluation criteria in solid tumors. Overall survival and time to progression were also evaluated. RESULTS: The recommended dose was determined to be 200 mg twice a day on days 1-14 and IV trastuzumab 6 mg/kg on day 1 of a 21-day cycle (n = 6). The Phase II study (n = 10) was terminated when the pre-planned efficacy evaluation found that none of the patients in the primary analysis set responded to combination SAHA and trastuzumab treatment. CONCLUSIONS: In patients with HER2-positive metastatic breast cancer who had relapsed or progressed during trastuzumab therapy, we observed no DLTs with SAHA 200 mg twice daily combined with trastuzumab; however, there was insufficient statistical evidence that adding SAHA reversed trastuzumab resistance in these patients.

Accuracy of Medicare Claim-based Algorithm to Detect Breast, Prostate, or Lung Cancer Bone Metastases.

BACKGROUND: We had previously developed an algorithm for Medicare claims data to detect bone metastases associated with breast, prostate, or lung cancer. This study was conducted to examine whether this algorithm accurately documents bone metastases on the basis of diagnosis codes in Medicare claims data. METHODS: We obtained data from Medicare claims and electronic medical records of patients 65 years or older with a breast, prostate, or lung cancer diagnosis at a teaching hospital and/or affiliated clinics during 2005 or 2006. We calculated the sensitivity and positive predictive value (PPV) of our algorithm using medical records as the "gold standard." The κ statistic was used to measure agreement between claims and medical record data. RESULTS: The agreement between claims and medical record data for bone metastases among breast, prostate, and lung cancer patients was 0.93, 0.90, and 0.69, respectively. The sensitivities of our algorithm for bone metastasis in patients with breast, prostate, and lung were 96.8% [95% confidence interval (CI)=83.8% to 99.4%], 91.7% (95% CI=78.2% to 97.1%), and 74.1% (95% CI=55.3% to 86.8%), respectively; and the PPVs were 90.9% (95% CI=76.4% to 96.9%), 91.7% (95% CI=78.2% to 97.1%), and 71.4% (95% CI=52.9% to 84.8%), respectively. CONCLUSIONS: The algorithm for detecting bone metastases in claims data had high sensitivity and PPV for breast and prostate cancer patients. Sensitivity and PPV were lower but still moderate for lung cancer patients.

A Pilot Study of the Combination of Entinostat with Capecitabine in Advanced Breast Cancer.

Background: Breast cancer has an unacceptably high recurrence rate when any residual disease is found following neoadjuvant treatment of high-risk disease. Based on clinical data suggesting an adjuvant role for epigenetic modifying agents in breast cancer and preclinical data suggesting synergistic activity of entinostat combined with capecitabine, we conducted a phase I, open-label study of these agents in metastatic breast cancer (MBC). Both agents have published doses for use in combination therapy, but the agents had not previously been combined with each other in a human trial. Methods: A multisite phase I dose escalation study was performed at two academic centers. Patients with pretreated, HER2-negative MBC, and measurable disease were enrolled. Dual dose escalation was performed via a Bayesian partial order continual assessment method. Dose levels ranged from entinostat 3 mg to 5 mg and capecitabine 800 mg/m2 to 1000 mg/m2. Results: Thirteen patients with MBC and a median of 4 lines of prior therapy were enrolled across four dose level combinations. The most common toxicities were neutropenia, thrombocytopenia, and palmar-plantar dysesthesia, which were expected toxicities. No new safety signals were observed. One dose-limiting toxicity was observed, which did not exceed a prespecified toxicity rate of 25%. The median treatment duration was 2.37 months. No partial nor complete responses were observed. The study was halted early prior to entering an expansion phase, due to drug supply limitations. Conclusion: The tested dosing combinations of entinostat and capecitabine are likely safe in heavily pretreated metastatic breast cancer. This study's clinical investigation of entinostat in breast cancer was halted, but drug development of this agent continues outside the US. There remains a need for postoperative adjuvant drug therapy for the subpopulation of breast cancer patients with high-risk residual cancer after curative therapy. This trial is registered with NCT03473639.

Oral SERD, a Novel Endocrine Therapy for Estrogen Receptor-Positive Breast Cancer.

Breast cancer is the most common cancer among women worldwide, and estrogen receptor-positive (ER+) breast cancer accounts for a significant proportion of cases. While various treatments are available, endocrine therapies are often the first-line treatment for this type of breast cancer. However, the development of drug resistance poses a significant challenge in managing this disease. ESR1 mutations have been identified as a common mechanism of endocrine therapy resistance in ER+ breast cancer. The first-generation selective estrogen receptor degrader (SERD) fulvestrant has shown some activity against ESR1 mutant tumors. However, due to its poor bioavailability and need for intramuscular injection, it may not be the optimal therapy for patients. Second-generation SERDs were developed to overcome these limitations. These newer drugs have improved oral bioavailability and pharmacokinetics, making them more convenient and effective for patients. Several oral SERDs are now in phase III trials for early and advanced ER+ breast cancer. This review summarizes the background of oral SERD development, the current status, and future perspectives.

Oral clodronate for adjuvant treatment of operable breast cancer (National Surgical Adjuvant Breast and Bowel Project protocol B-34): a multicentre, placebo-controlled, randomised trial.

BACKGROUND: Bisphosphonates are thought to act through the osteoclast by changing bone microenvironment. Previous findings of adjuvant clodronate trials in different populations with operable breast cancer have been mixed. The National Surgical Adjuvant Breast and Bowel Project (NSABP) protocol B-34 aims to ascertain whether oral clodronate can improve outcomes in women with primary breast cancer. METHODS: NSABP B-34 is a multicentre, randomised, double-blind, placebo-controlled study in 3323 women with stage 1-3 breast cancer. After surgery to remove the tumour, patients were stratified by age, axillary nodes, and oestrogen and progesterone receptor status and randomly assigned in a 1:1 ratio to either oral clodronate 1600 mg daily for 3 years (n=1662) or placebo (1661). The primary endpoint was disease-free survival, analysed by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00009945. FINDINGS: Median follow-up was 90·7 months (IQR 82·7-100·0) and 3311 patients had data for this period. Disease-free survival did not differ between groups (286 events in the clodronate group vs 312 in the placebo group; hazard ratio 0·91, 95% CI 0·78-1·07; p=0·27). Moreover, no differences were recorded for overall survival (0·84, 0·67-1·05; p=0·13), recurrence-free interval (0·83, 0·67-1·04; p=0·10), or bone metastasis-free interval (0·77, 0·55-1·07; p=0·12). Non-bone metastasis-free interval was slightly increased with clodronate (0·74, 0·55-1·00; p=0·047). Analyses in women age 50 years or older on study entry showed benefits of clodronate for recurrence-free interval (0·75, 0·57-0·99; p=0·045), bone metastasis-free interval (0·62, 0·40-0·95; p=0·027), and non-bone metastasis-free interval (0·63, 0·43-0·91; p=0·014), but not for overall survival (0·80, 0·61-1·04, p=0·094). Adherence to treatment at 3 years was 56% for the clodronate group and 60% for the placebo group. Grade 3 or higher liver dysfunction was noted in 23 of 1612 patients in the clodronate group and 12 of 1623 patients in the placebo group; grade 3-4 diarrhoea was noted in 28 patients in the clodronate group and in ten in the placebo group. There was one possible case of osteonecrosis of the jaw in the clodronate group. INTERPRETATION: Findings of NSABP B-34 suggest that bisphosphonates might have anticancer benefits for older postmenopausal women. A meta-analysis of adjuvant bisphosphonate trials is suggested before recommendations for use in non-osteoporotic postmenopausal women with primary breast cancer are made. FUNDING: National Cancer Institute, Bayer Oy (formerly Schering Oy).

Circulating tumor DNA association with residual cancer burden after neoadjuvant chemotherapy in triple-negative breast cancer in TBCRC 030.

Purpose: To examine circulating tumor DNA (ctDNA) and its association with residual cancer burden (RCB) using an ultrasensitive assay in patients with triple-negative breast cancer (TNBC) receiving neoadjuvant chemotherapy (NAT). Patients and Methods: We identified responders (RCB-0/1) and matched non-responders (RCB-2/3) from the phase II TBCRC 030 prospective study of neoadjuvant paclitaxel vs. cisplatin in TNBC. We collected plasma samples at baseline, three weeks, and twelve weeks (end of therapy). We created personalized ctDNA assays utilizing MAESTRO mutation enrichment sequencing. We explored associations between ctDNA and RCB status and disease recurrence. Results: Of 139 patients, 68 had complete samples and no additional NAT. Twenty-two were responders and 19 of those had sufficient tissue for whole-genome sequencing. We identified an additional 19 non-responders for a matched case-control analysis of 38 patients using a MAESTRO ctDNA assay tracking 319-1000 variants (median 1000) to 114 plasma samples from 3 timepoints. Overall, ctDNA positivity was 100% at baseline, 79% at week 3, and 55% at week 12. Median tumor fraction (TFx) was 3.7 × 10 -4 (range: 7.9 × 10 -7 to 4.9 × 10 -1 ). TFx decreased 285-fold from baseline to week 3 in responders and 24-fold in non-responders. Week 12 ctDNA clearance correlated with RCB: clearance was observed in 10/11 patients with RCB-0, 3/8 with RCB-1, 4/15 with RCB-2, and 0/4 with RCB-3. Among 6 patients with known recurrence five had persistent ctDNA at week 12. Conclusion: NAT for TNBC reduced ctDNA TFx by 285-fold in responders and 24-fold in non-responders. In 58% (22/38) of patients, ctDNA TFx dropped below the detection level of a commercially available test, emphasizing the need for sensitive tests. Additional studies will determine if ctDNA-guided approaches can improve outcomes.

Association of Radiotherapy Duration With Clinical Outcomes in Patients With Esophageal Cancer Treated in NRG Oncology Trials: A Secondary Analysis of NRG Oncology Randomized Clinical Trials.

Importance: For many types of epithelial malignant neoplasms that are treated with definitive radiotherapy (RT), treatment prolongation and interruptions have an adverse effect on outcomes. Objective: To analyze the association between RT duration and outcomes in patients with esophageal cancer who were treated with definitive chemoradiotherapy (CRT). Design, Setting, and Participants: This study was an unplanned, post hoc secondary analysis of 3 prospective, multi-institutional phase 3 randomized clinical trials (Radiation Therapy Oncology Group [RTOG] 8501, RTOG 9405, and RTOG 0436) of the National Cancer Institute-sponsored NRG Oncology (formerly the National Surgical Adjuvant Breast and Bowel Project, RTOG, and Gynecologic Oncology Group). Enrolled patients with nonmetastatic esophageal cancer underwent definitive CRT in the trials between 1986 and 2013, with follow-up occurring through 2014. Data analyses were conducted between March 2022 to February 2023. Exposures: Treatment groups in the trials used standard-dose RT (50 Gy) and concurrent chemotherapy. Main Outcomes and Measures: The outcomes were local-regional failure (LRF), distant failure, disease-free survival (DFS), and overall survival (OS). Multivariable models were used to examine the associations between these outcomes and both RT duration and interruptions. Radiotherapy duration was analyzed as a dichotomized variable using an X-Tile software to choose a cut point and its median value as a cut point, as well as a continuous variable. Results: The analysis included 509 patients (median [IQR] age, 64 [57-70] years; 418 males [82%]; and 376 White individuals [74%]). The median (IQR) follow-up was 4.01 (2.93-4.92) years for surviving patients. The median cut point of RT duration was 39 days or less in 271 patients (53%) vs more than 39 days in 238 patients (47%), and the X-Tile software cut point was 45 days or less in 446 patients (88%) vs more than 45 days in 63 patients (12%). Radiotherapy interruptions occurred in 207 patients (41%). Female (vs male) sex and other (vs White) race and ethnicity were associated with longer RT duration and RT interruptions. In the multivariable models, RT duration longer than 45 days was associated with inferior DFS (hazard ratio [HR], 1.34; 95% CI, 1.01-1.77; P = .04). The HR for OS was 1.33, but the results were not statistically significant (95% CI, 0.99-1.77; P = .05). Radiotherapy duration longer than 39 days (vs ≤39 days) was associated with a higher risk of LRF (HR, 1.32; 95% CI, 1.06-1.65; P = .01). As a continuous variable, RT duration (per 1 week increase) was associated with DFS failure (HR, 1.14; 95% CI, 1.01-1.28; P = .03). The HR for LRF 1.13, but the result was not statistically significant (95% CI, 0.99-1.28; P = .07). Conclusions and Relevance: Results of this study indicated that in patients with esophageal cancer receiving definitive CRT, prolonged RT duration was associated with inferior outcomes; female patients and those with other (vs White) race and ethnicity were more likely to have longer RT duration and experience RT interruptions. Radiotherapy interruptions should be minimized to optimize outcomes.

Mortality following bone metastasis and skeletal-related events among women with breast cancer: a population-based analysis of U.S. Medicare beneficiaries, 1999-2006.

The aim of the study is to quantify the impact of bone metastasis and skeletal-related events (SREs) on mortality in older breast cancer patients. Using the linked Surveillance, Epidemiology and End Results-Medicare database, we identified women aged 65 years or older diagnosed with breast cancer between July 1, 1999 and December 31, 2005 and followed them to determine deaths occurring through December 31, 2006. We classified patients as having possible bone metastasis and SREs using discharge diagnoses from inpatient claims and diagnoses paired with procedure codes from outpatient claims. We used Cox regression to estimate mortality hazards ratios (HR) among women with bone metastasis with or without SRE, compared with women without bone metastasis. Among 98,260 women with breast cancer (median follow-up, 3.3 years), 7,189 (7.3%) had bone metastasis either at breast cancer diagnosis (1.5%) or during follow-up (5.8%). SREs occurred in 3,319 (46%) of women with bone metastasis. HRs for risk of death were 4.9 (95% CI 4.7-5.1) and 6.2 (95% CI 5.9-6.5), respectively, for women with bone metastasis but no SRE and for women with bone metastasis plus SRE, compared with women without bone metastasis. In analyses restricted to women with bone metastasis, the adjusted HR was 1.5 (95% CI 1.4-1.6) for women with bone metastasis plus SRE, compared with women with bone metastasis but without SRE. Having a bone metastasis, as indicated by Medicare claims, was associated strongly with mortality among women with breast cancer. This association was stronger for bone metastasis complicated by SRE than for bone metastasis without SRE.

Inflammatory breast cancer with excellent response to pembrolizumab-chemotherapy combination: A case report.

Inflammatory breast cancer (IBC) is a rare variety of breast cancer accounting for two percent of breast cancer diagnoses in the United States. It is characterized by peau d'orange, breast edema and erythema on physical examination and dermal lymphatic invasion by tumor emboli on histological examination. Micrometastases to lymphatics and bone marrow at the time of diagnosis and angiogenic properties of IBC explain the high propensity of this cancer to relapse and metastasize, its aggressiveness and poor prognosis. Preoperative sequential anthracycline and taxane (plus trastuzumab and pertuzumab if HER2-positive) based chemotherapy is the current standard of care for IBC. We herein report a case of stage IIIC triple-negative IBC treated with pembrolizumab plus chemotherapy based neoadjuvant therapy with a complete clinical and complete pathological response. This is the first case of triple-negative IBC treated with this regimen reported in the literature, thereby providing clinical data on the tolerability and efficacy of pembrolizumab plus chemotherapy based neoadjuvant regimen for the treatment of IBC.

Genetic Polymorphisms and Correlation with Treatment-Induced Cardiotoxicity and Prognosis in Patients with Breast Cancer.

PURPOSE: Cardiac toxicity is a serious potential complication of HER2-directed therapies and anthracyclines. HER2 codon 655 and SLC28A3 gene polymorphisms have been reported to be associated with cardiac toxicity from anti-HER2 and anthracycline therapy, respectively. Association of the polymorphism at HER2 codon 655 with prognosis has also been reported. EXPERIMENTAL DESIGN: Whole blood samples from patients treated on a randomized adjuvant breast cancer trial (BCIRG-006) that compared chemotherapy with or without trastuzumab plus either anthracycline or nonanthracycline chemotherapy were tested for genetic polymorphisms in HER2 codon 655 and SLC28A3. Genotypes were correlated with cardiac function and disease-free survival (DFS) outcomes. RESULTS: Of 3,222 patients enrolled in BCIRG-006, 662 patient samples were successfully genotyped for the rs1136201 allele in HER2 (codon 655): 424 (64%) were AA, 30 (4.5%) were GG, and 208 (31%) were AG genotype. In addition, 665 patient samples were successfully genotyped for the rs7853758 allele in the SLC28A3 gene: 19 (3%) were AA, 475 (71%) were GG, and 171 (26%) were AG genotype. Follow-up time was 10 years. No correlation between DFS, cardiac event rate, or mean left ventricular ejection fraction (LVEF) and rs1136201 genotype was seen in the trastuzumab-treated or non-trastuzumab-treated patients. Moreover, mean LVEF and cardiac event rates were similar in all rs7853758 genotype groups treated with anthracycline-based therapy. CONCLUSIONS: In the largest study to date to evaluate whether two polymorphisms are associated with DFS and/or cardiac toxicity in HER2-positive breast cancer treated with trastuzumab and/or anthracyclines, we observed no correlation.

BRE12-158: A Postneoadjuvant, Randomized Phase II Trial of Personalized Therapy Versus Treatment of Physician's Choice for Patients With Residual Triple-Negative Breast Cancer.

PURPOSE: Patients with triple-negative breast cancer (TNBC) with residual disease after neoadjuvant chemotherapy (NAC) have high risk of recurrence with prior data suggesting improved outcomes with capecitabine. Targeted agents have demonstrated activity across multiple cancer types. BRE12-158 was a phase II, multicenter trial that randomly allocated patients with TNBC with residual disease after NAC to genomically directed therapy versus treatment of physician choice (TPC). PATIENTS AND METHODS: From March 2014 to December 2018, 193 patients were enrolled. Residual tumors were sequenced using a next-generation sequencing test. A molecular tumor board adjudicated all results. Patients were randomly allocated to four cycles of genomically directed therapy (arm A) versus TPC (arm B). Patients without a target were assigned to arm B. Primary end point was 2-year disease-free survival (DFS) among randomly assigned patients. Secondary/exploratory end points included distant disease-free survival, overall survival, toxicity assessment, time-based evolution of therapy, and drug-specific outcomes. RESULTS: One hundred ninety-three patients were randomly allocated or were assigned to arm B. The estimated 2-year DFS for the randomized population only was 56.6% (95% CI, 0.45 to 0.70) for arm A versus 62.4% (95% CI, 0.52 to 0.75) for arm B. No difference was seen in DFS, distant disease-free survival, or overall survival for the entire or randomized populations. There was increased uptake of capecitabine for TPC over time. Patients randomly allocated later had less distant recurrences. Circulating tumor DNA status remained a significant predictor of outcome with some patients demonstrating clearance with postneoadjuvant therapy. CONCLUSION: Genomically directed therapy was not superior to TPC for patients with residual TNBC after NAC. Capecitabine should remain the standard of care; however, the activity of other agents in this setting provides rationale for testing optimal combinations to improve outcomes. Circulating tumor DNA should be considered a standard covariate for trials in this setting.

Impact of Anti-HER2 Treatments Combined With Atezolizumab on the Tumor Immune Microenvironment in Early or Metastatic Breast Cancer: Results From a Phase Ib Study.

BACKGROUND: Despite advances, there continues to be unmet need in breast cancer. Combining anti-programmed death-ligand 1 (PD-L1) cancer immunotherapy atezolizumab with other targeted therapies may enhance T-cell-dependent cytolytic antitumor activity. METHODS: This open-label, phase Ib study evaluated the safety of atezolizumab-based combinations with antibody-dependent cellular cytotoxicity or antibody-drug conjugate (ADC) agents. Patients with unresectable human epidermal growth factor receptor 2-positive (HER2+) locally advanced or metastatic breast cancer (mBC) received atezolizumab with trastuzumab/pertuzumab, atezolizumab with the ADC ado-trastuzumab emtansine (T-DM1), or atezolizumab with trastuzumab/pertuzumab and docetaxel. In an early-breast cancer (eBC) "window of opportunity" study, patients with operable HER2+ locally advanced or inflammatory eBC received neoadjuvant atezolizumab with trastuzumab/pertuzumab or atezolizumab/T-DM1, followed by docetaxel, carboplatin, and trastuzumab/pertuzumab. Exploratory outcomes included tumor response and biomarkers. RESULTS: By March 15, 2019, 73 patients were enrolled. Safety findings were consistent with the treatment components' individual profiles. Objective responses were observed in 2 of 6 and 5 of 14 patients in 2 mBC cohorts receiving atezolizumab/T-DM1 and in 6 of 6 patients with mBC receiving atezolizumab, trastuzumab/pertuzumab, and docetaxel. PD-L1 in immune cells was the only biomarker that increased with atezolizumab/T-DM1. In the window of opportunity cohorts, PD-L1 levels and CD8+ T-cell infiltration increased from baseline in HER2+ eBC tumors receiving atezolizumab with trastuzumab/pertuzumab or T-DM1, irrespective of response. Despite increases in T-cell and B-cell gene signatures with trastuzumab/pertuzumab, but not T-DM1, neither combination promoted T-cell receptor clonal expansion. CONCLUSION: Atezolizumab with antibody-dependent cellular cytotoxicity or ADC agents appears safe and may activate the adaptive immune system of patients with HER2+ eBC tumors more than those with mBC tumors.