Global Results of Implantable Loop Recorder for Detection of Atrial Fibrillation After Stroke: Reveal LINQ Registry.

BACKGROUND: We aimed to quantify the incidence of atrial fibrillation (AF) in patients with cryptogenic stroke globally, as well as separately in patients in and outside of Japan, using an implantable loop recorder from a prospective, observational, Reveal LINQ Registry. METHODS AND RESULTS: Patients developing cryptogenic stroke and monitored by implantable loop recorder for searching AF were studied. The primary end point was incidence of AF within 36 months after insertion. Secondary end points were recurrent ischemic stroke/transient ischemic attack and AF-related treatment strategies. A total of 271 patients (61.6±14.3 years, 170 men, 60 from Japan) were enrolled from 12 countries. AF was detected in 28.2% at 36 months. The median time from enrollment to AF detection was 7.9 months. During the first 12 months, the AF detection rate slope was relatively steeper in the Japanese subgroup versus non-Japanese patients. However, by 3 years, the cumulative incidence of AF detection did not differ between groups. Age was the only variable associated with AF detection (hazard ratio, 1.05 [95% CI, 1.02-1.07] per year), trending higher in older age groups. Of the 271 patients, 11 (4.1%) developed recurrent ischemic stroke/transient ischemic attack; AF was detected by implantable loop recorder in only 1 of these patients. Patients with detected AF were more commonly taking oral anticoagulation than those without AF at the last follow-up (64.7% versus 25.3%, P<0.001). CONCLUSIONS: The rate of AF detection was similar to other studies in stroke populations monitored by implantable loop recorders, including CRYSTAL-AF (Cryptogenic Stroke and Underlying Atrial Fibrillation), STROKE-AF (Stroke of Unknown Cause and Underlying Atrial Fibrillation) and PER-DIEM (Post-Embolic Rhythm Detection With Implantable Versus External Monitoring). Patients with detected AF more commonly initiated anticoagulation than those without AF.

Utilization of remote reprogramming to manage insertable cardiac monitor arrhythmia alert burden.

INTRODUCTION: The increasing use of insertable cardiac monitors (ICMs) for long-term continuous arrhythmia monitoring creates a high volume of transmissions and a significant workload for clinics. The ability to remotely reprogram device alert settings without in-office patient visits was recently introduced, but its impact on clinic workflow compared to the previous ICM iteration is unknown. METHODS: The aim of this real-world study was to evaluate the impact of device reprogramming capabilities on ICM alert burden and on clinic workflow. Deidentified data was obtained from US patients and a total of 19 525 receiving a LINQ II were propensity score-matched with 19 525 implanted with LINQ TruRhythm (TR) ICM based on age and reason for monitoring. RESULTS: After reprogramming, ICM alerts reduced by 20.5% (p < .001). Compared with patients monitored with LINQ TR, patients with LINQ II had their device reprogrammed sooner after implant and more frequently during follow-up. Adoption of remote programming was projected to lead to an annual total clinic time savings of 211 h per 100 ICM patients managed. CONCLUSION: These data suggest that utilization of ICM alert reprogramming has increased with remote capabilities, which may reduce clinic and patient burden for ICM follow-up and free clinician time for other valuable patient care activities.

Atrial Fibrillation In Patients With Stroke Attributed to Large- or Small-Vessel Disease: 3-Year Results From the STROKE AF Randomized Clinical Trial.

Importance: The STROKE AF study found that in patients with prior ischemic stroke attributed to large-artery atherosclerotic disease (LAD) or small-vessel occlusive disease (SVD), 12% developed AF over 1 year when monitored with an insertable cardiac monitor (ICM). The occurrence over subsequent years is unknown. Objectives: To compare the rates of AF detection through 3 years of follow-up between an ICM vs site-specific usual care in patients with prior ischemic stroke attributed to LAD or SVD. Design, Setting, and Participants: This multicenter, randomized (1:1) clinical trial took place at 33 sites in the US with enrollment between April 2016 and July 2019 and 3-year follow-up through July 2022. Eligible patients were aged 60 years or older, or aged 50 to 59 years with at least 1 additional stroke risk factor and had an index ischemic stroke attributed to LAD or SVD within 10 days prior to ICM insertion. Of the 496 patients enrolled, 492 were randomized and 4 were excluded. Interventions: ICM monitoring vs site-specific usual care. Main Outcomes and Measures: The prespecified long-term outcome of the trial was AF detection through study follow-up (up to 3 years). AF was defined as an episode lasting more than 30 seconds, adjudicated by an expert committee. Results: In total, 492 patients were randomized and included in the analyses (median [IQR] age, 66 [60-74] years; 307 men [62.4%] and 185 women [37.6%]), of whom 314 completed 3-year follow-up (63.8%). The incidence rate of AF at 3 years was 21.7% (46 patients) in the ICM group vs 2.4% (5 patients) in the control group (hazard ratio, 10.0; 95% CI, 4.0-25.2; P < .001). Conclusions and Relevance: Patients with ischemic stroke attributed to LAD or SVD face an increasing risk of AF over time and most of the AF occurrences are not reliably detected by standard medical monitoring methods. One year of negative monitoring should not reassure clinicians that patients who have experienced stroke will not develop AF over the next 2 years. Trial Registration: ClinicalTrials.gov Identifier: NCT02700945.

Predictors of Atrial Fibrillation in Patients With Stroke Attributed to Large- or Small-Vessel Disease: A Prespecified Secondary Analysis of the STROKE AF Randomized Clinical Trial.

Importance: The Stroke of Known Cause and Underlying Atrial Fibrillation (STROKE AF) trial found that approximately 1 in 8 patients with recent ischemic stroke attributed to large- or small-vessel disease had poststroke atrial fibrillation (AF) detected by an insertable cardiac monitor (ICM) at 12 months. Identifying predictors of AF could be useful when considering an ICM in routine poststroke clinical care. Objective: To determine the association between commonly assessed risk factors and poststroke detection of new AF in the STROKE AF cohort monitored by ICM. Design, Setting, and Participants: This was a prespecified analysis of a randomized (1:1) clinical trial that enrolled patients between April 1, 2016, and July 12, 2019, with primary follow-up through 2020 and mean (SD) duration of 11.0 (3.0) months. Eligible patients were selected from 33 clinical research sites in the US. Patients had an index stroke attributed to large- or small-vessel disease and were 60 years or older or aged 50 to 59 years with at least 1 additional stroke risk factor. A total of 496 patients were enrolled, and 492 were randomly assigned to study groups (3 did not meet inclusion criteria, and 1 withdrew consent). Patients in the ICM group had the index stroke within 10 days before insertion. Data were analyzed from October 8, 2021, to January 28, 2022. Interventions: ICM monitoring vs site-specific usual care (short-duration external cardiac monitoring). Main Outcomes and Measures: The ICM device automatically detects AF episodes 2 or more minutes in length; episodes were adjudicated by an expert committee. Cox regression multivariable modeling included all parameters identified in the univariate analysis having P values <.10. AF detection rates were calculated using Kaplan-Meier survival estimates. Results: The analysis included the 242 participants randomly assigned to the ICM group in the STROKE AF study. Among 242 patients monitored with ICM, 27 developed AF (mean [SD] age, 66.6 [9.3] years; 144 men [60.0%]; 96 [40.0%] women). Two patients had missing baseline data and exited the study early. Univariate predictors of AF detection included age (per 1-year increments: hazard ratio [HR], 1.05; 95% CI, 1.01-1.09; P = .02), CHA2DS2-VASc score (per point: HR, 1.54; 95% CI, 1.15-2.06; P = .004), chronic obstructive pulmonary disease (HR, 2.49; 95% CI, 0.86-7.20; P = .09), congestive heart failure (CHF; with preserved or reduced ejection fraction: HR, 6.64; 95% CI, 2.29-19.24; P < .001), left atrial enlargement (LAE; HR, 3.63; 95% CI, 1.55-8.47; P = .003), QRS duration (HR, 1.02; 95% CI, 1.00-1.04; P = .04), and kidney dysfunction (HR, 3.58; 95% CI, 1.35-9.46; P = .01). In multivariable modeling (n = 197), only CHF (HR, 5.06; 95% CI, 1.45-17.64; P = .05) and LAE (HR, 3.32; 1.34-8.19; P = .009) remained significant predictors of AF. At 12 months, patients with CHF and/or LAE (40 of 142 patients) had an AF detection rate of 23.4% vs 5.0% for patients with neither (HR, 5.1; 95% CI, 2.0-12.8; P < .001). Conclusions and Relevance: Among patients with ischemic stroke attributed to large- or small-vessel disease, CHF and LAE were associated with a significantly increased risk of poststroke AF detection. These patients may benefit most from the use of ICMs as part of a secondary stroke prevention strategy. However, the study was not powered for clinical predictors of AF, and therefore, other clinical characteristics may not have reached statistical significance. Trial Registration: ClinicalTrials.gov Identifier: NCT02700945.

Syncope Recurrence and Downstream Diagnostic Testing after Insertable Cardiac Monitor Placement for Syncope.

Despite advances in syncope evaluation strategies and risk stratification, the high cost of syncope is largely driven by extensive and often repetitive testing. This analysis of a large deidentified US claims database compared the use of diagnostic tests, therapeutic procedures, and the recurrence rate of acute syncope events before and after placement of an insertable cardiac monitor (ICM) in syncope patients. The patients had a minimum of 1 year of continuous enrollment before and 2 years after ICM placement. Among 2140 patients identified, a statistically significant reduction in the use of 14 out of 18 tests was observed during follow-up compared with pre-ICM testing. During the 2-year follow-up, 28.3% of patients underwent cardiac therapeutic interventions after a median of 127 days. Significantly fewer patients experienced acute syncope events during the 1st and 2nd years of ICM follow-up compared with the 1-year pre-ICM period, and the frequency of events per patient also decreased. In conclusion, reductions in diagnostic testing and acute syncope events were observed after ICM placement in a large real-world cohort of unexplained syncope patients. Further studies are needed to prospectively assess the impact of ICM vs. short-term monitoring on patient outcomes and healthcare utilization.

Healthcare utilization and clinical outcomes after ablation of atrial fibrillation in patients with and without insertable cardiac monitoring.

BACKGROUND: Compared with short-term electrocardiogram (ECG) monitors, insertable cardiac monitors (ICMs) have been shown to increase atrial fibrillation (AF) detection rates and the opportunity to treat recurrent AF in patients postablation. OBJECTIVE: To examine healthcare utilization and clinical outcomes following AF ablation, in patients with vs without ICM. METHODS: Retrospective analysis pooling Optum Clinformatics and Medicare Fee-for-service 5% Sample claims databases. Patients with an AF ablation between January 1, 2011, and March 31, 2018 who received an ICM implant within 1 year pre-/postablation were propensity score matched 1:3 to patients without ICM. Outcomes included AF-related healthcare utilization, medication use, and occurrence of composite severe cardiovascular events (stroke / transient ischemic attack, major bleeds, systemic embolism, AF- or heart failure-related hospitalization, or death). RESULTS: A total of 1000 ICM patients and 2998 non-ICM patients were included. During mean follow-up of 33 ± 16 months postablation, ICM patients experienced significantly fewer severe cardiovascular events (1.09 ± 2.22 vs 1.37 ± 4.19, P = .008) and associated costs ($20,757 vs $29,106, P = .0005). ICM patients had a greater number of AF-related clinic visits (16.8 vs 11.6 visits, P < .0001) and were more likely to receive a repeat ablation (38.7% vs 32.4%, P = .0003). Total all-cause costs during follow-up were not statistically different. Discontinuation of oral anticoagulation was higher in ICM patients at 1 year (44% vs 31%, P < .0001) and 2 years (73% vs 64%, P = .0012). CONCLUSION: A shift from acute, reactive care to routine outpatient management was observed in patients with long-term ECG monitoring. Results suggest closer patient management in patients with long-term monitoring after an AF ablation and an improvement in outcomes, at similar overall cost.

Effect of Long-term Continuous Cardiac Monitoring vs Usual Care on Detection of Atrial Fibrillation in Patients With Stroke Attributed to Large- or Small-Vessel Disease: The STROKE-AF Randomized Clinical Trial.

Importance: Patients with ischemic stroke attributed to large- or small-vessel disease are not considered at high risk for atrial fibrillation (AF), and the AF incidence rate in this population is unknown. Objectives: To determine whether long-term cardiac monitoring is more effective than usual care for AF detection in patients with stroke attributed to large- or small-vessel disease through 12 months of follow-up. Design, Setting, and Participants: The STROKE-AF trial was a randomized (1:1), multicenter (33 sites in the US) clinical trial that enrolled 496 patients between April 2016 and July 2019, with primary end point follow-up through August 2020. Eligible patients were aged 60 years or older or aged 50 to 59 years with at least 1 additional stroke risk factor and had an index stroke attributed to large- or small-vessel disease within 10 days prior to insertable cardiac monitor (ICM) insertion. Interventions: Patients randomized to the intervention group (n = 242) received ICM insertion within 10 days of the index stroke; patients in the control group (n = 250) received site-specific usual care consisting of external cardiac monitoring, such as 12-lead electrocardiograms, Holter monitoring, telemetry, or event recorders. Main Outcomes and Measures: Incident AF lasting more than 30 seconds through 12 months. Results: Among 492 patients who were randomized (mean [SD] age, 67.1 [9.4] years; 185 [37.6%] women), 417 (84.8%) completed 12 months of follow-up. The median (interquartile range) CHA2DS2-VASc (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, stroke or transient ischemic attack, vascular disease, age 65 to 74 years, sex category) score was 5 (4-6). AF detection at 12 months was significantly higher in the ICM group vs the control group (27 patients [12.1%] vs 4 patients [1.8%]; hazard ratio, 7.4 [95% CI, 2.6-21.3]; P < .001). Among the 221 patients in the ICM group who received an ICM, 4 (1.8%) had ICM procedure-related adverse events (1 site infection, 2 incision site hemorrhages, and 1 implant site pain). Conclusions and Relevance: Among patients with stroke attributed to large- or small-vessel disease, monitoring with an ICM compared with usual care detected significantly more AF over 12 months. However, further research is needed to understand whether identifying AF in these patients is of clinical importance. Trial Registration: ClinicalTrials.gov Identifier: NCT02700945.

Use of the HAVOC Score to Identify Patients at Highest Risk of Developing Atrial Fibrillation.

BACKGROUND: Recent studies using insertable cardiac monitors (ICMs) show a high incidence of atrial fibrillation (AF). Further identifying subsets of patients who could benefit most from ICMs is desirable. We evaluated whether the HAVOC risk score which predicts AF in patients with cryptogenic stroke also predicts AF detection by ICMs in those without recent stroke. METHODS: Participants were included from the prospective, industry-sponsored REVEAL AF study assessing AF incidence in patients with CHADS2 scores ≥3 or =2 with 1 or more additional AF risk factors, who had ICM data and were not receiving anti-arrhythmic drugs. Ischemic stroke occurring less than 1 year prior to enrollment or documented AF were exclusion criteria. AF was defined as an adjudicated ICM-detected episode ≥6 min in duration. HAVOC scores were calculated by assigning 4 points for congestive heart failure, 2 points for each of hypertension, age ≥75 years, valvular disease, and coronary artery disease, and 1 point for each of peripheral vascular disease and obesity (body mass index >30). Scores classified risk as low (0-4), intermediate (5-9), or high (10-14); corresponding AF detection rates were compared using the log-rank test. AF incidence rates in patients with and without a history of remote stroke at baseline were also compared. RESULTS: Among 391 participants, the mean age was 71.5 ± 9.8 years and 186 (47.6%) were women. In total, 130 (33.2%) developed AF over 18 months. Stratification by HAVOC risk score was: 95 (24%) low, 241 (62%) intermediate, and 55 (14%) high. At 18 months, AF incidence in patients with low HAVOC scores (19.5%) was lower than in those with intermediate (32.1%) or high (34.2%) scores. AF incidence was similar among those with (n = 78) versus without (n = 313) remote stroke (27.3% vs. 29.8%; median time from stroke to ICM insertion was 4.2 [2.2-8.2] years). CONCLUSIONS: The HAVOC risk score identified a subset of individuals at greatest risk of developing AF, while AF incidence rates were similar among those with and without remote stroke. The use of the HAVOC score could help identify those at greatest likelihood of manifesting AF during long-term monitoring.

Burden of oral anticoagulation in embolic stroke of undetermined source without atrial fibrillation.

OBJECTIVE: Prevention of recurrent stroke in patients with embolic stroke of undetermined source (ESUS) is challenging. The advent of safer anticoagulation in the form of direct oral anticoagulants (DOACs) has prompted exploration of prophylactic anticoagulation for all ESUS patients, rather than anticoagulating just those with documented atrial fibrillation (AF). However, recent trials have failed to demonstrate a clinical benefit, while observing increased bleeding. We modeled the economic impact of anticoagulating ESUS patients without documented AF across multiple geographies. METHODS: CRYSTAL-AF trial data were used to assess ischaemic stroke event rates in ESUS patients confirmed AF-free after long-term monitoring. Anticipated bleeding event rates (including both minor and major bleeds) with aspirin, dabigatran 150 mg, and rivaroxaban 20 mg were sourced from published meta-analyses, whilst a 30% ischaemic stroke reduction for both DOACs was assumed. Cost data for clinical events and pharmaceuticals were collected from the local payer perspective. RESULTS: Compared with aspirin, dabigatran and rivaroxaban resulted in 17.9 and 29.9 additional bleeding events per 100 patients over a patient's lifetime, respectively. Despite incorporating into our model the proposed 30% reduction in ischaemic stroke risk, both DOACs were cost-additive over patient lifetime, as the costs of bleeding events and pharmaceuticals outweighed cost savings associated with the reduction in ischaemic strokes. DOACs added £5953-£7018 per patient (UK), €6683-€7368 (Netherlands), €4933-€9378 (Spain), AUD$5353-6539 (Australia) and $26,768-$32,259 (US) of payer cost depending on the agent prescribed. Additionally, in the U.S. patient pharmacy co-payments ranged from $2468-$12,844 depending on agent and patient plan. In all settings, cost-savings could not be demonstrated even when the modelling assumed 100% protection from recurrent ischaemic strokes, due to the very low underlying risk of recurrent ischaemic stroke in this population (1.27 per 100 patient-years). CONCLUSIONS: Anticoagulation of non-AF patients may cause excess bleeds and add substantial costs for uncertain benefits, suggesting a personalised approach to anticoagulation in ESUS patients.

Safety of in-hospital insertable cardiac monitor procedures performed outside the traditional settings: results from the Reveal LINQ in-office 2 international study.

BACKGROUND: Historically, the majority of insertable cardiac monitor (ICM) procedures were performed in the cardiac catheterization (cath) lab, electrophysiology (EP) lab, or operating room (OR). The miniaturization of ICMs allows the procedure to be relocated within the hospital without compromising patient safety. We sought to estimate the rate of untoward events associated with procedures performed within the hospital but outside the traditional settings and to characterize resource utilization, procedure time intervals, and physician experience. METHODS: The Reveal LINQ in-Office 2 (RIO 2) International study was a single arm, multicenter, prospective study. Patients indicated for an ICM and willing to undergo device insertion outside the cath/EP lab or OR were eligible and followed for 90 days after insertion. RESULTS: A total of 191 patients (45.5% female aged 63.8 ± 26.9 years) underwent successful Reveal LINQ ICM insertion at 17 centers in Europe, Canada and Australia. The median total visit duration was 106 min (interquartile range [IQR]: 55-61). Patient preparation and patient education accounted for 10 min (IQR: 5-20) and 10 min (IQR: 8-15) of total visit duration, respectively. Preparation and education occurred in the procedure room for 90.6 and 60.2% of patients, respectively. There were no untoward events (0.0, 95% CI: 0.0-2.1%) though four patients presented with procedure-related adverse events that did not require invasive intervention. Physicians rated procedure location as convenient or very convenient. CONCLUSIONS: The Reveal LINQ™ ICM insertion can be safely and efficiently performed in the hospital outside the cath/EP lab or OR. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT02412488 ; registered on April 9, 2015.

Real-world comparison of in-hospital Reveal LINQ insertable cardiac monitor insertion inside and outside of the cardiac catheterization or electrophysiology laboratory.

BACKGROUND: Traditionally, insertable cardiac monitor (ICM) procedures have been performed in the cardiac catheterization (CATH) or electrophysiology (EP) laboratory. The introduction of the miniaturized Reveal LINQ ICM has led to simplified and less invasive procedures, affording hospitals flexibility in planning where these procedures occur without compromising patient safety or outcomes. METHODS: The present analysis of the ongoing, prospective, observational, multicenter Reveal LINQ Registry sought to provide real-world feasibility and safety data regarding the ICM procedure performed in the CATH/EP lab or operating room and to compare it with insertions performed outside of these traditional hospital settings. Patients included had at least a 30-day period after the procedure to account for any adverse events. RESULTS: We analyzed 1222 patients (58.1% male, age 61.0 ± 17.1 years) enrolled at 18 centers in the US, 17 centers in Middle East/Asia, and 15 centers in Europe. Patients were categorized into 2 cohorts according to the location of the procedure: in-lab (CATH lab, EP lab, or operating room) (n = 820, 67.1%) and out-of-lab (n = 402, 32.9%). Several differences were observed regarding baseline and procedure characteristics. However, no significant differences in the occurrence of procedure-related adverse events (AEs) were found; of 19 ICM/procedure-related AEs reported in 17 patients (1.4%), 11 occurred in the in-lab group (1.3%) and 6 in the out-of-lab group (1.5%) (P = .80). CONCLUSIONS: This real-world analysis demonstrates the feasibility of performing Reveal LINQ ICM insertion procedures outside of the traditional hospital settings without increasing the risk of infection or other adverse events.

Real-World Use of Prophylactic Antibiotics in Insertable Cardiac Monitor Procedures.

BACKGROUND: The use of prophylactic antibiotics during insertable cardiac monitor (ICM) procedures is a carryover of the common practice used with therapeutic cardiac implantable electronic devices. We sought to characterize the current practice of ICM insertion procedures to evaluate the influence of prophylactic antibiotic administration on the occurrence of infections. METHODS: We characterized insertion procedures and procedure-related infections from an ongoing multicenter registry (Reveal LINQ(TM) Registry). In order to accurately capture infections, only patients enrolled before or the day of insertion who also had a record of whether or not preoperative antibiotics were used were included in this analysis. Infections were defined based on the physician's assessment and reported upon occurrence. Patients were categorized into two analysis cohorts based on prophylactic antibiotic use. RESULTS: We analyzed 375 patients from 14 U.S. centers (age 63.1 ± 15.6 years; male 54.1%). Approximately two-thirds of patients (66.4%) did not receive any preprocedural antibiotics. The overall infection rate was 1.1% (0.3-2.7% confidence interval [CI]) and corresponded to four events. In the group that did not receive preprocedural antibiotics, there were two minor infections (0.8%, [0.1-2.9% CI]), whereas in the group receiving preprocedural antibiotics a serious and a minor infection occurred (1.6%, [0.2-5.6% CI]); this serious infection resulted in an explant. CONCLUSIONS: Current real-world practice shows that ICM insertions are increasingly performed without the use of prophylactic antibiotics, which is associated with a very low infection rate.

Safety Profile of a Miniaturized Insertable Cardiac Monitor: Results from Two Prospective Trials.

BACKGROUND: Insertable cardiac monitors (ICMs) are used to continuously monitor the patient's electrocardiogram. In response to patient activation or based on automated device algorithms, arrhythmia episodes are stored and automatically transmitted daily to the clinician. Thus, ICMs can be used to diagnose arrhythmias in at-risk patients and in those with symptoms potentially attributable to arrhythmias. The ICM described in this report has undergone a dramatic change in size and method of insertion. METHODS: To evaluate the safety profile of the ICM procedure, we analyzed procedure-related adverse events (AEs) from two separate trials: A controlled, nonrandomized multicenter study (Reveal LINQ(TM) Usability study) and a multicenter registry (Reveal LINQ(TM) Registry) evaluating real-world experience. For the Registry we reported all procedure-related AEs upon occurrence, whereas for the Usability study, we reported events occurring during the first month of follow-up. RESULTS: The Usability study enrolled 151 patients (age 56.6 ± 12.1 years; male 67%) at 16 centers; during follow-up, an infection was observed in 1.3% patients and a procedure-related serious AE (SAE) in 0.7% patients. The Registry enrolled 122 patients (age 61.0 ± 17.8 years; male 47%) at seven centers; during follow-up, an infection was observed in 1.6% patients and a procedure-related SAE in 1.6% patients. CONCLUSIONS: The cumulative experience from a controlled clinical trial and a "real-world" registry demonstrate that the new ICM can be inserted with very low incidence of AEs.

Functional identification of cancer-specific methylation of CDO1, HOXA9, and TAC1 for the diagnosis of lung cancer.

PURPOSE: Non-small cell lung cancer (NSCLC) is the leading cause of cancer mortality in the world. Novel diagnostic biomarkers may augment both existing NSCLC screening methods as well as molecular diagnostic tests of surgical specimens to more accurately stratify and stage candidates for adjuvant chemotherapy. Hypermethylation of CpG islands is a common and important alteration in the transition from normal tissue to cancer. EXPERIMENTAL DESIGN: Following previously validated methods for the discovery of cancer-specific hypermethylation changes, we treated eight NSCLC cell lines with the hypomethylating agent deoxyazacitidine or trichostatin A. We validated the findings using a large publicly available database and two independent cohorts of primary samples. RESULTS: We identified >300 candidate genes. Using The Cancer Genome Atlas (TCGA) and extensive filtering to refine our candidate genes for the greatest ability to distinguish tumor from normal, we define a three-gene panel, CDO1, HOXA9, and TAC1, which we subsequently validate in two independent cohorts of primary NSCLC samples. This three-gene panel is 100% specific, showing no methylation in 75 TCGA normal and seven primary normal samples and is 83% to 99% sensitive for NSCLC depending on the cohort. CONCLUSION: This degree of sensitivity and specificity may be of high value to diagnose the earliest stages of NSCLC. Addition of this three-gene panel to other previously validated methylation biomarkers holds great promise in both early diagnosis and molecular staging of NSCLC.

Neoadjuvant chemoradiation therapy is beneficial for clinical stage T2 N0 esophageal cancer patients due to inaccurate preoperative staging.

BACKGROUND: It remains unclear if patients with clinical stage T2 N0 (cT2 N0) esophageal cancer should be offered induction therapy vs surgical intervention alone. METHODS: This was a retrospective cohort study of cT2 N0 patients undergoing induction therapy, followed by surgical resection, or resection alone, at the Johns Hopkins Hospital from 1989 to 2009. Kaplan-Meier analysis was used to compare all-cause mortality in cT2 N0 patients who had resection alone vs those who had induction chemoradiation therapy, followed by resection. RESULTS: A study cohort of 69 patients was identified and divided into two groups: 55 patients (79.7%) received induction therapy and 14 (20.3%) did not. No statistically significant difference in 5-year survival rate was observed for the two groups: 49.5% for the resection-only group and 53.8% for the induction group. More than 50% of cT2 N0 patients were understaged. CONCLUSIONS: For cT2 N0 esophageal cancer patients, the benefit of neoadjuvant therapy is still unclear. Induction therapy for cT2 N0 did not translate into a statistically significant improvement in survival. However, due to the significant understaging of T2 N0 patients, we recommend neoadjuvant therapy to all cT2N0 patients before operation.

Multiplexed methylation profiles of tumor suppressor genes in bladder cancer.

Changes in DNA methylation of tumor suppressors can occur early in carcinogenesis and are potentially important early indicators of cancer. The objective of this study was to assess the methylation of 25 tumor suppressor genes in bladder cancer using a methylation-specific (MS) multiplex ligation-dependent probe amplification assay (MLPA). Initial analyses in bladder cancer cell lines (n = 14) and fresh-frozen primary bladder tumor specimens (n = 31) supported the panel of genes selected being altered in bladder cancer. The process of MS-MLPA was optimized for its application in body fluids using two independent training and validation sets of urinary specimens (n = 146), including patients with bladder cancer (n = 96) and controls (n = 50). BRCA1 (71.0%), WT1 (38.7%), and RARB (38.7%) were the most frequently methylated genes in bladder tumors, with WT1 methylation being significantly associated with tumor stage (P = 0.011). WT1 and PAX5A were identified as methylated tumor suppressors. In addition, BRCA1, WT1, and RARB were the most frequently methylated genes in urinary specimens. Receiver operating characteristic curve analyses revealed significant diagnostic accuracies in both urinary sets for BRCA1, RARB, and WT1. The novelty of this report relates to applying MS-MLPA, a multiplexed methylation technique, for tumor suppressors in bladder cancer and body fluids. Methylation profiles of tumor suppressor genes were clinically relevant for histopathological stratification of bladder tumors and offered a noninvasive diagnostic strategy for the clinical management of patients affected with uroepithelial neoplasias.

Combination epigenetic therapy has efficacy in patients with refractory advanced non-small cell lung cancer.

UNLABELLED: Epigenetic alterations are strongly associated with the development of cancer. We conducted a phase I/II trial of combined epigenetic therapy with azacitidine and entinostat, inhibitors of DNA methylation and histone deacetylation, respectively, in extensively pretreated patients with recurrent metastatic non-small cell lung cancer. This therapy is well tolerated, and objective responses were observed, including a complete response and a partial response in a patient who remains alive and without disease progression approximately 2 years after completing protocol therapy. Median survival in the entire cohort was 6.4 months (95% CI 3.8-9.2), comparing favorably with existing therapeutic options. Demethylation of a set of 4 epigenetically silenced genes known to be associated with lung cancer was detectable in serial blood samples in these patients and was associated with improved progression-free (P = 0.034) and overall survival (P = 0.035). Four of 19 patients had major objective responses to subsequent anticancer therapies given immediately after epigenetic therapy. SIGNIFICANCE: This study demonstrates that combined epigenetic therapy with low-dose azacitidine and entinostat results in objective, durable responses in patients with solid tumors and defines a blood-based biomarker that correlates with clinical benefit.

Fluorescence in situ hybridization in the definitive diagnosis of malignant mesothelioma in effusion cytology.

BACKGROUND: Distinction of malignant mesothelioma (MM) from reactive mesothelial cells (RM) in effusions is notoriously difficult. The aim of our study was to test chromosomal aberrations detected by fluorescence in situ hybridization (FISH) in the diagnosis of MM in effusion cytology and to explore the potential role of p16, p14, and p15 gene methylation as an alternative mechanism of tumor suppressor gene inactivation. METHODS: Fifty-two effusions of biopsy-proven MM and 28 benign effusions were retrospectively analyzed by multitarget FISH assay for aberrations of chromosomes 3, 7, 17, and 9p21. In case of a negative result, the corresponding MM biopsy specimen was analyzed. Methylation-specific polymerase chain reaction (MSP) for p16, p14, and p15 was performed on FISH-negative MM biopsy specimens. RESULTS: Seventy-nine percent of effusions with biopsy-proven MM had chromosomal aberrations, with loss of 9p21 as the most common finding. All benign effusions were FISH negative. Sensitivity, specificity, and positive and negative predictive values for detection of MM by FISH were 79%, 100%, 100%, and 72%, respectively. Six of nine FISH-negative effusions with biopsy-proven MM were also FISH negative in the MM biopsy specimens. Four of five FISH-negative biopsy specimens showed promoter methylation in p16 and p14 as compared with one of 12 benign controls. CONCLUSIONS: FISH is a sensitive and highly specific method for the definitive diagnosis of MM in effusion cytology. In the subset of FISH-negative MM, tumor suppressor genes on the chromosomal region 9p21 are often inactivated by promoter methylation.

Low-dose exposure to gamma rays induces specific gene regulations in normal human keratinocytes.

Skin is the organ most exposed to various environmental aggressors, including ionizing radiation. Low-dose and low-dose-rate exposures to gamma rays account for most occupational, medical or environmental irradiations. To examine whether this type of exposure triggers specific molecular responses, cultured primary keratinocytes isolated from adult normal skin were irradiated with single acute doses of 1 cGy or 2 Gy. DNA microarrays containing 10,500 probes were used to assess transcriptional changes over a time course between 3 and 72 h postirradiation. Keratinocytes were studied at a differentiated stage to mimic the response of cells from the suprabasal layers of the epidermis. A major finding of this study was the identification of an important number of low-dose-specific genes (140), most of which were modulated at 48 h. Clustering analysis also revealed low-dose-specific profiles. One of these clusters (17 known genes) was further analyzed using Gibbs sampling algorithm, which led to the identification of 7 putative promoter sequences. These results show for the first time that low-dose ionizing radiation is able to induce specific transcriptional responses in human keratinocytes. Our findings support the potential usefulness of microarrays in biological dosimetry studies after low-dose exposures.

Activation of an energy providing response in human keratinocytes after gamma irradiation.

We performed a microarray study on human differentiated HaCaT keratinocytes exposed to ionizing radiation (2 or 10 Gy). At 3 h after exposure, more than 150 known and unknown genes were found regulated in irradiated HaCaT keratinocytes. Among the genes regulated at 3 h, those involved in cell energy metabolism appeared to be the most abundant and the most responsive. Two mitochondrial ATP-synthases and several other genes involved in energy producing pathways, such as glucose metabolism, were induced, whereas many genes from energy requiring pathways were shut down. These changes in energy metabolism were confirmed both in normal primary keratinocytes and in HaCaT keratinocytes by RT-PCR and proteins studies. Moreover, measures of intracellular ATP revealed a 50% increase in keratinocytes immediately after irradiation, supporting an energy procurement response. The overall results indicate that irradiation induces an immediate burst of ATP that seems to be a general response of human differentiated keratinocytes to the radiation stress. This article contains Supplementary Material available at http://www.mrw.interscience.wiley.com/suppmat/0730-2312/suppmat/v95.html