Susan Dent

The field of cardio-oncology was born from the necessity for recognition and management of cardiovascular diseases among patients with cancer. This need for this specialty continues to grow as patients with cancer live longer as a result of lifesaving targeted and immunologic cancer therapies beyond the usual chemotherapy and/or radiation therapy. Often, potentially cardiotoxic anticancer treatment is necessary in patients with baseline cardiovascular disease. Moreover, patients may need to continue therapy in the setting of incident cancer therapy-associated cardiotoxicity. Herein, we present and discuss the concept of permissive cardiotoxicity as a novel term that represents an essential concept in the field of cardio-oncology and among practicing cardio-oncology specialists. It emphasizes a proactive rather than reactive approach to continuation of lifesaving cancer therapies in order to achieve the best oncologic outcome while mitigating associated and potentially off-target cardiotoxicities.

<h4>Aims</h4>The national incidence, risk factors, and associated mortality of atrial fibrillation (AF) in breast cancer patients are unknown.<h4>Methods and results</h4>Using the Surveillance, Epidemiology, and End Results-Medicare-linked database, we identified females, ≥66 years old, with a new primary diagnosis of breast cancer from 2007 through 2014. These patients were individually matched 1:1 to Medicare enrolees without cancer, and each pair was followed for 1 year to identify a primary outcome of AF. Cumulative incidence was calculated using competing risk survival statistics. Following this, identifying risk factors of AF among breast cancer patients was conducted using the adjusted Cox proportional hazards model. Finally, Kaplan-Meier methods and adjusted Cox proportional hazards modelling were performed to estimate mortality in breast cancer patients with incident and prevalent AF. This study included 85 423 breast cancer patients. Among these 9425 (11.0%) had AF diagnosis prior to the breast cancer diagnosis. New-onset AF was diagnosed in 2993 (3.9%) patients in a 1-year period after the breast cancer diagnosis [incidence 3.3%, 95% confidence interval (CI) 3.0-3.5%, at 1 year; higher rate in the first 60 days (0.6%/month)]. Comparatively, the incidence of new-onset AF in matched non-cancer controls was 1.8% (95% CI 1.6-2.0%). Apart from traditional demographic and cardiovascular risk factors, breast cancer stage was strongly associated with the development of AF [American Joint Committee on Cancer (AJCC) Stage II/III/IV vs. I: adjusted hazard ratio (aHR) 1.51/2.63/4.21, respectively]. New-onset AF after breast cancer diagnosis (aHR 3.00) is associated with increased 1-year cardiovascular mortality.<h4>Conclusion</h4>AF incidence is significantly higher in women after a breast cancer diagnosis. Higher breast cancer stages at diagnos are significantly associated with a higher risk of AF. New-onset AF in the new breast cancer diagnosis setting increases 1-year cardiovascular mortality but not breast cancer-related mortality.<h4>Key question</h4>What are the incidence, prevalence, risk factors and mortality outcomes of atrial fibrillation (AF) in a multi-ethnic representative United States cohort of breast cancer patients?<h4>Key finding</h4>Annual incidence for AF is 3.9% with highest rate in the first 60 days after cancer diagnosis. Cancer stage and grade are the strongest risk factors for AF. New onset AF after breast cancer increases all-cause and cardiovascular mortality.<h4>Take home message</h4>AF incidence is higher in breast cancer patients and is associated with later stage and grade at diagnosis of breast cancer. Involving cardio-oncology in those who develop AF after cancer diagnosis should be encouraged to improve their cardiovascular and overall prognosis.

BACKGROUND: The phase III SANDPIPER study assessed taselisib (GDC-0032), a potent, selective PI3K inhibitor, plus fulvestrant in estrogen receptor-positive, HER2-negative, PIK3CA-mutant locally advanced or metastatic breast cancer. PATIENTS AND METHODS: Postmenopausal women with disease recurrence/progression during/after an aromatase inhibitor were randomized 2 : 1 to receive taselisib (4 mg; taselisib arm) or placebo (placebo arm) plus fulvestrant (500 mg). Stratification factors were visceral disease, endocrine sensitivity, and geographic region. Patients with PIK3CA-mutant tumors (central cobas® PIK3CA Mutation Test) were randomized separately from those without detectable mutations. The primary endpoint was investigator-assessed progression-free survival (INV-PFS) in patients with PIK3CA-mutant tumors. Secondary endpoints included objective response rate, overall survival, clinical benefit rate, duration of objective response, PFS by blinded independent central review (BICR-PFS), safety, and time to deterioration in health-related quality of life. RESULTS: The PIK3CA-mutant intention-to-treat population comprised 516 patients (placebo arm: n = 176; taselisib arm: n = 340). INV-PFS was significantly improved in the taselisib {7.4 months [95% confidence interval (CI), 7.26-9.07]} versus placebo arm (5.4 months [95% CI, 3.68-7.29]) (stratified hazard ratio [HR] 0.70; 95% CI, 0.56-0.89; P = 0.0037) and confirmed by BICR-PFS (HR 0.66). Secondary endpoints, including objective response rate, clinical benefit rate, and duration of objective response, showed consistent improvements in the taselisib arm. Safety was assessed in all randomized patients who received at least one dose of taselisib/placebo or fulvestrant regardless of PIK3CA-mutation status (n = 629). Serious adverse events were lower in the placebo versus taselisib arm (8.9% versus 32.0%). There were more discontinuations (placebo arm: 2.3%; taselisib arm: 16.8%) and dose reductions (placebo arm: 2.3%; taselisib arm: 36.5%) in the taselisib arm. CONCLUSION: SANDPIPER met its primary endpoint; however, the combination of taselisib plus fulvestrant has no clinical utility given its safety profile and modest clinical benefit.

BACKGROUND: In breast cancer patients, coincidental detection of CAC at chest CT may be important in determining cardiovascular (CV) outcomes and facilitate CV disease primary prevention strategies. METHODS: 408 consecutive breast cancer patients referred to cardiac oncology clinic were included in the study. 256 patients without a prior history of coronary artery disease had undergone a chest CT. CT images were reviewed to detect CAC. Framingham risk score (FRS) was calculated and patient electronic medical records were interrogated to document the incidence of a composite clinical end point of all-cause mortality and cardiac events (coronary revascularization, heart failure hospitalization and de novo atrial fibrillation). Prevalence of statin prescribing was also collected. RESULTS: Patients were followed for a median of 6.5 years. 112 clinical events occurred. Clinical follow up was 98%. CAC was found in 26% of patients. On multivariable analysis, CAC and advance cancer stage, but not FRS predicted the composite clinical end point (OR for CAC 2.59, p < 0.01). CAC but not FRS also predicted the incidence of cardiac events (OR for CAC 4.90, p < 0.01). CAC was present in 7.3% of patients with low FRS; none had been prescribed a statin. In patients with CAC and FRS ≥ 10%, 45% were not on a statin. CONCLUSION: CAC is a common coincidental finding at CT chest in breast cancer patients referred to cardiac oncology. CAC but not FRS was predictive of composite clinical events and cardiac events. Detection of CAC at chest CT could alter the prescribing of primary prevention strategies to help prevent future cardiac events in breast cancer patients.

Background: Patients with cancer treatment-related cardiotoxicity, which may manifest as heart failure (HF), can present with dyspnea. Nurses frequently assess, triage and offer self-care strategies to patients experiencing dyspnea in both the cardiology and oncology settings. However, there are no known tools available for nurses to manage patients in the setting of cancer treatment-related cardiotoxicity. The objective of this study was to adapt and evaluate the acceptability of an evidence-informed symptom practice guide (SPG) for use by nurses over the telephone for the assessment, triage, and management of patients experiencing dyspnea due to cancer treatment-related cardiotoxicity. Methods: The CAN-IMPLEMENT© methodology guided this descriptive study. A systematic search was conducted in four databases to identify cardio-oncology and HF guidelines and systematic reviews. Screening was conducted by two reviewers, with data extracted into a recommendation matrix from eligible guidelines and systematic reviews on: assessment criteria, medications, and/or self-care strategies to manage dyspnea. Healthcare professionals with an expertise in oncology and/or cardiology were recruited using purposeful and snowball sampling. Evaluation of acceptability of the adapted SPG was gathered through semi-structured interviews and a survey with open- and closed-ended questions. Quantitative findings and participant feedback from the interviews and the open-ended survey questions were analyzed descriptively. Results: Of 490 citations, seven HF guidelines were identified. Evidence from these guidelines was added to the original SPG. Eleven healthcare professionals completed the interview and acceptability survey. The adapted SPG was iteratively revised three times during the interviews. The original SPG was adaptable, and participants indicated the adapted SPG was comprehensive, easy to follow, and would be useful in clinical practice. Conclusions: This study highlights the lack of knowledge tools and available clinical practice guidelines to guide healthcare professionals to assess, triage and/or offer self-care strategies to patients with cancer treatment-related cardiotoxic dyspnea. Moreover, most nurses require assistance to differentiate among the various causes of dyspnea from oncology treatment in order to triage severity appropriately. Further research should focus on evaluating the validity of the adapted SPG in clinical practice.