The optimal slow pathway ablation site in atrioventricular nodal reentrant tachycardia cases with an inferiorly located His bundle

INTRODUCTION

The optimal slow pathway (SP) ablation site in cases with an inferiorly located His bundle (HIS) remains unclear.

METHODS AND RESULTS

In 45 patients with atrioventricular nodal reentrant tachycardia, the relationship between the HIS location and successful SP ablation site was assessed in electroanatomical maps. We assessed the location of the SP ablation site relative to the bottom of the coronary sinus ostium in the superior-to-inferior (SPSI), anterior-to-posterior (SPAP), and right-to-left (SPRL) directions. The HIS location was assessed in the same manner. The HIS location in the superior-to-inferior direction (HISSI), SPSI, SPAP, and SPRL were 17.7 ± 6.4, 1.7 ± 6.4, 13.6 ± 12.3, and -1.0 ± 13.0 mm, respectively. The HISSI was positively correlated with SPSI (R2 = 0.62; P < .01) and SPAP (R2 = 0.22; P < .01), whereas it was not correlated with SPRL (R2 = 0.01; P = .65). The distance between the HIS and SP ablation site was 17.7 ± 6.4 mm and was not affected by the location of HIS. The ratio of the amplitudes of atrial and ventricular potential recorded at the SP ablation site did not differ between the high HIS group (HISSI ≥ 13 mm) and low HIS group (HISSI < 13 mm) (0.10 ± 0.06 vs. 0.10 ± 0.06; P = .38).

CONCLUSION

In cases with an inferiorly located HIS, SP ablation should be performed at a lower and more posterior site than in typical cases.

Incidence, distribution, and electrogram characteristics of endocardial-epicardial connections identified by ultra-high-resolution mapping during a left atrial posterior wall isolation of atrial fibrillation

PURPOSE

The left atrial posterior wall (LAPW) can be a target for atrial fibrillation (AF) catheter ablation but is sometimes difficult to completely isolate due to the presence of endocardial-epicardial connections. We aimed to investigate the incidence and distribution of epicardial residual connections (epi-RCs) and the electrogram characteristics at epi-RC sites during an initial LAPW isolation.

METHODS

We retrospectively studied 102 AF patients who underwent LAPW mapping before and after a first-pass linear ablation along the superior and inferior LAPW (pre-ablation and post-ablation maps) using an ultra-high-resolution mapping system (Rhythmia, Boston Scientific).

RESULTS

Epi-RCs were observed in 41 patients (40.2%) and were widely distributed in the middle LAPW area and surrounding it. The sites with epi-RCs had a higher bipolar voltage amplitude and greater number of fractionated components than those without (median, 1.09 mV vs. 0.83 mV and 3.9 vs. 3.4 on the pre-ablation map and 0.38 mV vs. 0.27 mV and 8.5 vs. 4.2 on the post-ablation map, respectively; P < 0.001). Receiver operating characteristic analyses demonstrated that the number of fractionated components on the post-ablation map had a larger area under the curve of 0.847 than the others, and the sensitivity and specificity for predicting epi-RCs were 95.4% and 62.1%, respectively, at an optimal cutoff of 5.0.

CONCLUSIONS

Among the patients with epi-RCs after a first-pass LAPW linear ablation, areas with a greater number of fractionated components (> 5.0 on the post-ablation LAPW map) may have endocardial-epicardial connections and may be potential targets for touch-up ablation to eliminate the epi-RCs.

Noncontact Charge Density Mapping-Guided Ablation of Persistent Atrial Fibrillation With a Multiple Trigger-Based Mechanism

We present a case of radiofrequency catheter ablation of persistent atrial fibrillation (AF) with a trigger-based mechanism, guided by novel noncontact charge density mapping, which resulted in the simultaneous achievement of the termination of AF and complete elimination of multiple triggers that induced repeated recurrences of AF immediately after cardioversion. (Level of Difficulty: Advanced.).

Bilateral Cardiac Sympathetic Denervation for Treatment-Resistant Ventricular Arrhythmias in Heart Failure Patients with a Reduced Ejection Fraction

The sympathetic nervous system plays an important role in life-threatening ventricular arrhythmias (VAs). Bilateral cardiac sympathetic denervation (BCSD) is performed for refractory VAs. We sought to assess our institutional experience with BCSD in managing treatment-resistant monomorphic ventricular tachycardia (MMVT) in heart failure patients with a reduced ejection fraction (HFrEF).Four patients with HFrEF (EF 30.0 ± 8.2%, New York Heart Association [NYHA] class IV 1) underwent BCSD for MMVT (VT storm 3, repetitive VT requiring implantable cardioverter defibrillator [ICD] therapy 1) refractory to antiarrhythmic drugs, catheter ablation and ICD therapy. BCSD was effective for suppressing VT in 3 patients for whom deep sedation was effective for suppressing VT. One patient remained alive after 14 months of follow-up without episodes of VT. One patient died of acute myocardial infarction before discharge and 1 patient died from unknown cause at 3 days post-discharge. In contrast, BCSD was completely ineffective for suppressing VT in a patient with NYHA class IV for whom deep sedation and stellate ganglion block were ineffective. This patient died on the 10th post-CSD day, despite left ventricular assist device implantation. In all cases, BCSD was successfully performed without procedure-related complications.Despite the limited number of cases, our results showed that BCSD in patients with HFrEF suppressed refractory MMVT in acute-phase except for a patient with NYHA class IV; however, the prognoses were not good. BCSD may be a treatment option at an earlier stage of NYHA and a bridge to orthotopic heart transplantation, even if BCSD is effective for suppressing VAs.

Local impedance measurements during contact force‐guided cavotricuspid isthmus ablation for predicting an effective radiofrequency ablation

Background

An ablation catheter capable of contact force (CF) and local impedance (LI) monitoring (IntellaNav StablePoint, Boston Scientific) has been recently launched. We evaluated the relationship between the CF and LI values during radiofrequency catheter ablation (RFCA) along the cavotricuspid isthmus (CTI).

Methods

Fifty consecutive subjects who underwent a CTI‐RFCA using IntellaNav StablePoint catheters were retrospectively studied. The initial CF and LI at the start of the RF applications and mean CF and minimum LI during the RF applications were measured. The absolute and percentage LI drops were calculated as the difference between the initial and minimum LIs and 100 × absolute LI drop/initial LI, respectively.

Results

We analyzed 602 first‐pass RF applications. A weak correlation was observed between the initial CF and LI (r = 0.13) and between the mean CF and LI drops (r = 0.22). The initial LI and absolute and percentage LI drops were greater at effective ablation sites than ineffective ablation sites (median, 151 vs. 138 Ω, 22 vs. 14 Ω, and 14.4% vs. 9.9%; p < .001), but the initial and mean CF did not differ. At optimal cutoffs of 21 Ω and 10.8% for the absolute and percentage LI drops according to the receiver‐operating characteristic analysis, the sensitivity, and specificity for predicting an effective ablation were 57.4% and 88.9% and 80.0%, and 61.1%, respectively.

Conclusions

The effective sites during the CF‐guided CTI‐RFCA had greater initial LI and LI drops than the ineffective sites. Absolute and percentage LI drops of 21 Ω and 10.8% may be appropriate targets for an effective ablation.

Incidental findings on computed tomography for preoperative assessment before transcatheter aortic valve implantation in japanese patients

Background

Extra-cardiovascular incidental findings (IFs) on preoperative computed tomography (CT) are frequently observed in transcatheter aortic valve implantation (TAVI) candidates. However, the backgrounds of TAVI candidates and comorbidities differ based on the race and/or country, and data on IFs in a specific population are not always applicable to another.

Objective

To assess the prevalence, type, and clinical impact of IFs in Japanese TAVI candidates.

Methods

This was a retrospective, single-center, observational study. CT reports of 257 TAVI candidates were reviewed, and IFs were classified as (a) insignificant: findings that did not require further investigation, treatment, or follow-up; (b) intermediate: findings that needed to be followed up or were considered for further investigation but did not affect the planning of TAVI; and (c) significant: findings that required further investigation immediately or affected the planning of TAVI.

Results

At least one IF was found in 254 patients (98.8%). Insignificant, intermediate, and significant IFs were found in 253 (98.4%), 153 (59.5%), and 34 (13.2%) patients, respectively. Newly indicated significant IFs were found in 19 patients (7.4%). In 2 patients (0.8%), TAVI was canceled because of significant IFs. In patients who consequently underwent TAVI, the presence of significant IFs was not associated with the duration from CT performance to TAVI [28 (19–40) days vs. 27 (19–43) days, p=0.74] and all-cause mortality during the median follow-up period of 413 (223–805) days (p=0.44).

Conclusion

Almost all Japanese TAVI candidates had at least one IF, and the prevalence of significant IFs was not negligible. Although the presence of significant IFs was not associated with mid-term mortality, appropriate management of IFs was considered important.

Funding Acknowledgement

Type of funding sources: None.

Regression of electrocardiographic left ventricular hypertrophy after transcatheter aortic valve replacement for aortic stenosis

Background

The changes in electrocardiographic left ventricular hypertrophy (ECG-LVH) after transcatheter aortic valve replacement (TAVR) are not fully elucidated.

Methods

This retrospective single-center study investigated 156 patients who underwent TAVR for severe aortic stenosis. Twelve-leads ECGs obtained before and at 2 days and 1, 6 and 12 months after TAVR were analyzed. Patients with an implanted pacemaker, with a bundle branch block before or after TAVR or whose electrocardiogram at any measuring point was not available were excluded. As an assessment of ECG-LVH, Sokolow-Lyon voltage, Cornell voltage, Cornell product and Peguero–Lo Presti voltage were evaluated.

Results

Finally, 64 patients were included. Sokolow-Lyon voltage, Cornell voltage, Cornell product and Peguero–Lo Presti voltage significantly decreased between 1 and 6 months after TAVR compared to baseline. The prevalence of ECG-LVH criteria for each parameter decreased as well. QRS duration significantly decreased at 6 months after TAVR and the number of patients with strain pattern decreased significantly at 1 month when compared to baseline. When the patients were divided into two groups, those with and without ECG-LVH at baseline, ECG-LVH parameter values decreased significantly, especially in patients with ECG-LVH at baseline.

Conclusion

Regression of ECG-LVH after TAVR was demonstrated as per various criteria of ECG-LVH. The voltages and prevalence of ECG-LVH decreased significantly between 1 and 6 months after TAVR.

Funding Acknowledgement

Type of funding sources: None.

Symptomatic and asymptomatic intracerebral hemorrhages detected by magnetic resonance imaging after catheter ablation of atrial fibrillation

PURPOSE

Symptomatic intracerebral hemorrhages (ICHs) are a rare complication after atrial fibrillation (AF) catheter ablation, while the incidence of asymptomatic ICHs detected by magnetic resonance (MR) imaging remains unclear. This study aimed to investigate the incidence, characteristics, and predictors of new-onset ICHs on MR imaging after AF ablation.

METHODS

We retrospectively studied 1257 consecutive AF ablation procedures in 1201 patients who underwent MR imaging on the day after the procedure. Repeat MR imaging within 3 months post-ablation was available in 352 procedures.

RESULTS

Old ICHs on the initial MR imaging were observed in 28 procedures (2.2%). Post-ablation new ICHs were observed in 14 procedures (4.0%), including one symptomatic (0.3%) and 13 (3.7%) asymptomatic ICHs. One patient had a new ICH on the initial MR imaging, while the remaining 13 had such on the repeat MR imaging. A univariate analysis revealed that a previous ischemic stroke or transient ischemic attack (TIA) and the CHA₂DS₂-VASc score were positive predictors of new ICHs (odds ratios, 5.502 and 1.435; P = 0.004 and 0.044). The lesion diameter did not significantly differ between the old and new ICHs (median, 6.1 mm vs. 8.0 mm, P = 0.281), while the predominant location differed (lobar areas, 22.6% vs. 53.3%; cerebellum, 22.6% vs. 20.0%; others, 54.8% vs. 26.7%; P = 0.026).

CONCLUSIONS

A few asymptomatic ICHs may occur after AF ablation. Most of the post-ablation new ICHs occurred a few days or later after the procedure. A previous ischemic stroke/TIA and the CHA₂DS₂-VASc score may be risk factors for post-ablation ICHs.

The prevalence and characteristics of candidates for percutaneous left atrial appendage occlusion using a WATCHMAN device among patients who underwent atrial fibrillation ablation in a Japanese population

BACKGROUND

Percutaneous left atrial appendage occlusion (LAAO) using a WATCHMAN device could be a treatment option for patients with non-valvular atrial fibrillation (AF) with thromboembolic and bleeding risk. We sought to determine the prevalence and characteristics of patients with AF ablation who are potential candidates for WATCHMAN implantation in a Japanese population.

METHODS

We enrolled 2443 consecutive patients who had previously undergone AF ablation and transesophageal echocardiography (TEE). We assessed their clinical characteristics and measured their LAA orifice diameter and depth retrospectively using the obtained TEE images. We defined patients who met both anatomical criteria (LAA orifice max diameter: 17-31 mm and LAA max depth > LAA orifice max diameter) and clinical criteria (CHA₂DS₂-VASc score ≥ 2 and HAS-BLED score ≥ 3) as LAAO candidates.

RESULTS

Among the 2443 enrolled patients, 361 (15%) met the clinical criteria, and 1928 (79%) met the anatomical criteria. Thus 12% (293/2443) of the total patient group met the criteria of LAAO candidates. LAAO candidates showed larger left atrial (LA) volume (77.6 ± 30.1 vs. 67.7 ± 29.1 mL, P < 0.001), larger LAA orifice diameter (22.5 ± 3.2 vs. 22.0 ± 4.3 mm, P = 0.026), and larger LAA depth (28.9 ± 4.6 vs. 27.0 ± 4.8 mm, P < 0.001). LAAO candidates made up only 23% of patients with CHA₂DS₂-VASc score ≥ 2 (N = 1295), whereas 78% of patients with a HAS-BLED score ≥ 3 (N = 378) were LAAO candidates.

CONCLUSION

Twelve percent of patients who underwent AF ablation were potential candidates for LAAO using a WATCHMAN device in this Japanese population. It is imperative to evaluate bleeding risk when considering the indications for LAAO.

Prevalence, characteristics, and predictors of endocardial and nonendocardial conduction gaps during local impedance-guided extensive pulmonary vein isolation of atrial fibrillation with high-resolution mapping

INTRODUCTION

Local impedance (LI) drops during radiofrequency ablation can predict lesion formation. Some conduction gaps during pulmonary vein isolation (PVI) can be associated with nonendocardial connections. This study aimed to investigate the incidence, characteristics, and predictors of endocardial and nonendocardial conduction gaps during an LI-guided PVI.

METHODS AND RESULTS

We prospectively enrolled 157 consecutive patients undergoing an initial LI-guided extensive PVI of atrial fibrillation (AF). After the first-pass encirclement, the residual conduction gaps and reconnected gaps were mapped using Rhythmia (Boston Scientific) and a mini-basket catheter. Right and left PV (RPV/LPV) gaps were observed in 22.3% and 18.5% of the patients, respectively: 27 endocardial and 49 nonendocardial gaps. The carina regions were common sites for the gaps (51 carina-related vs. 25 noncarina-related). The carina-related gaps consisted of more nonendocardial gaps than endocardial gaps (RPVs: 90.0% vs. 10.0%, p = .001; LPVs: 76.2% vs. 23.8%, p < .001). A univariate analysis revealed that paroxysmal AF and the left atrial (LA) volume index for RPV endocardial gaps (odds ratio [OR]: 8.640 and 0.946; p = .043 and 0.009), minor right inferior PV diameter for RPV nonendocardial gaps (OR: 1.165; p = .028), and major left inferior PV diameter for LPV endocardial gaps (OR: 1.233; p = .028) were significant predictors.

CONCLUSIONS

During the LI-guided PVI, approximately two-thirds of the conduction gaps were nonendocardial. The carina regions had more conduction gaps than noncarina regions, which was due to the presence of nonendocardial connections. Paroxysmal AF, a lower LA volume index, and larger inferior PV diameters may increase the risk of conduction gaps.

Impact of the size of non-ablated left atrial posterior wall area on outcomes after extensive encircling pulmonary vein isolation

The aim of this study was to evaluate the impact of the size of the isolated surface area and non-ablated left atrial posterior area after extensive encircling pulmonary vein isolation (EEPVI) for non-paroxysmal atrial fibrillation (AF) on arrhythmia recurrence. This study included 132 consecutive persistent AF patients who underwent EEPVI guided by Ablation Index (AI). The isolated antral surface area (IASA) excluding the pulmonary veins, the non-ablated left atrial (LA) posterior wall surface area (PWSA), the ratio of IASA to LA surface area (IASA/LA ratio), and the ratio of PWSA to LA surface area (PWSA/LA ratio) were assessed using CARTO3 and the association with AF and atrial tachycardia (AT) recurrence was examined. At a mean follow-up of 13.2 ± 7.3 months, sinus rhythm was maintained in 115 (87%) patients. In the univariate Cox regression analysis, the factors that significantly predicted AT/AF recurrence were a history of heart failure, a higher CHA₂DS₂-VASc score, a larger LA diameter, and a larger PWSA/LA ratio. Multivariate Cox regression analysis revealed that the independent predictors of AT/AF recurrence were LA diameter [hazard ratio (HR) 1.120 per 1 mm increase; 95% confidence interval (CI) 1.006-1.247; P = 0.039] and PWSA/LA ratio (HR 1.218 per 1% increase; 95% CI 1.041-1.425; P = 0.014). Receiver operating characteristics curve analysis yielded an optimal cut-off value of 8% for the PWSA/LA ratio. The Kaplan-Meier survival curve showed that patients with a larger PWSA/LA ratio had poorer clinical outcomes (Log-rank P = 0.001). A larger PWSA/LA ratio was associated with a high AT/AF recurrence rate in patients with non-paroxysmal atrial fibrillation.

Hypertrophic Cardiomyopathy Complicated by Cardiac Sarcoidosis Diagnosed by Both the Morphological Abnormalities and the Time Course of the Disease

The definite diagnosis of cardiac sarcoidosis (CS) can be difficult because it mimics other cardiomyopathies and morphological abnormalities during its time course. Distinguishing CS isolated cardiac sarcoidosis from other cardiomyopathies is very important for the introduction of immunosuppressive therapy.In this study, we report a patient who had initially been diagnosed with hypertrophic obstructive cardiomyopathy (HOCM). The patient developed complete atrioventricular block (CAVB) and morphological abnormalities, which led to his primary diagnosis being re-conducted. Moreover, we made a definite diagnose of isolated CS (ICS) based on the guideline for the diagnosis and treatment using ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG-PET/CT)¹⁾ and performed tailor-made treatment including immunosuppressive therapy.

Effect of preventing air intrusion on silent strokes during atrial fibrillation ablation using a mini-basket catheter

BACKGROUND

Air bubble intrusion through transseptal sheaths during left atrial (LA) catheter ablation can cause cerebral embolisms, especially when using complex-shape catheters. This study aimed to compare the incidence of silent cerebral events (SCEs) after atrial fibrillation (AF) catheter ablation using a mini-basket catheter (IntellaMap Orion; Boston Scientific) between the following groups: group SP, strict prevention of LA air intrusion and group CP, conventional air intrusion prevention.

METHODS

We enrolled 123 consecutive AF patients (group SP, n = 61 and group CP, n = 62) who underwent brain magnetic resonance imaging after a local-impedance-guided ablation using one mini-basket catheter and one circular mapping catheter. The preventive strategy in group SP included (a) the insertion of the mini-basket catheter into the transseptal sheaths in a container filled with heparinized saline and (b) no exchange of all catheters over the sheaths.

RESULTS

SCEs were detected in 67 patients (54.5%), and the incidence of SCEs did not significantly differ between groups SP and CP (55.7% vs 53.2%; P = .780). A multivariate analysis demonstrated that an older age, non-paroxysmal AF, and radiofrequency (RF) power output were independent positive predictors of SCEs (odds ratios: 1.079, 5.613, and 1.405; P = .005, <.001, and .012). On the follow-up MR imaging, 83.5% of the SCEs in group SP and 87.7% in group CP disappeared (P = .398).

CONCLUSIONS

Strict prevention of LA air intrusion may have no additional effect for reducing the incidence of SCEs after local impedance-guided AF ablation using a mini-basket catheter. An older age, non-paroxysmal AF, and high-power RF applications may increase the risk of SCEs.

Incidence and characteristics of silent cerebral embolisms after radiofrequency-based atrial fibrillation ablation: A propensity score-matched analysis between different mapping catheters and indices for guiding ablation

INTRODUCTION

The difference in the incidence and characteristics of silent cerebral events (SCEs) after radiofrequency-based atrial fibrillation (AF) ablation between the different mapping catheters and indices used for guiding radiofrequency ablation remains unclear. This study aimed to compare the incidence and characteristics of postablation SCEs between the following two groups: Group C, Ablation Index-guided ablation using two circular mapping catheters with CARTO (Biosense Webster); Group R, local impedance-guided ablation using one mini-basket catheter and one circular mapping with Rhythmia (Boston Scientific).

METHODS AND RESULTS

Of 211 consecutive patients who underwent an AF ablation and brain magnetic resonance (MR) imaging after the ablation, 120 patients (each group, n = 60) were selected by propensity score matching. SCEs were detected in 37 patients (30.8%). Group R had a higher incidence of SCEs (51.7% vs. 10.0%; p < .001) and more SCEs per patient (median, 3 vs. 1, p = .028) than Group C. A multivariate analysis demonstrated that nonparoxysmal AF and being Group R were independent positive predictors of SCEs (odds ratios, 6.930 and 15.464; both p < .001). On the follow-up MR imaging, all SCEs in Group C and 87.9% of the SCEs in Group R disappeared (p = .537).

CONCLUSIONS

Group R had a significantly higher incidence of SCEs than Group C. Most probably the use of a complexly designed basket mapping catheter is the reason for the difference in the incidence of SCEs but further validation is needed. A nonparoxysmal form of AF may also increase the risk of SCEs during these ablation procedures.

Optimal local impedance drops for an effective radiofrequency ablation during cavo-tricuspid isthmus ablation

PURPOSE

A novel ablation catheter capable of local impedance (LI) monitoring (IntellaNav MiFi OI, Boston Scientific) has been recently introduced to clinical practice. We aimed to determine the optimal LI drops for an effective radiofrequency ablation during cavo-tricuspid isthmus (CTI) ablation.

METHODS

This retrospective observational study enrolled 50 consecutive patients (68 ± 9 years; 34 males) who underwent a CTI ablation using the IntellaNav MiFi OI catheter, guided by Rhythmia. The LI at the start of radiofrequency applications (initial LI) and minimum LI during radiofrequency applications were evaluated. The absolute and percentage LI drops were defined as the difference between the initial and minimum LIs and 100× absolute LI drop/initial LI, respectively.

RESULTS

A total of 518 radiofrequency applications were analyzed. The absolute and percentage LI drops were significantly greater at effective ablation sites than ineffective sites (median, 15 ohms vs 8 ohms, P < .0001; median, 14.7% vs 8.3%, P < .0001). A receiver-operating characteristic analysis demonstrated that at optimal cutoffs of 12 ohms and 11.6% for the absolute and percentage LI drops, the sensitivity and specificity for predicting the effectiveness of the ablation were 66.5% and 88.2%, and 65.1% and 88.2%, respectively. Finally, bidirectional conduction block along the CTI was achieved in all patients.

CONCLUSIONS

During the LI-guided CTI ablation, the effective RF ablation sites exhibited significantly greater absolute and percentage LI drops than the ineffective RF ablation sites. Absolute and percentage LI drops of 12 ohms and 11.6% may be suitable targets for effective ablation.

Abstract 5574: In vivo model development for immune cell-based therapeutics

The implementation of various mouse models is critical to asses safety, efficacy, and short- and long-term persistence of therapeutic modalities, especially for cell-based therapies. To increase our repertoire of viable humanized murine models, we developed two in vivo models by taking advantage of Taconic's immunodeficient mice, one monitoring graft versus host disease (GvHD) and the other addressing human natural killer (NK) cell cytotoxicity. We utilized NOG mice to develop a model of GvHD, by transplanting human PBMCs at varying doses and monitoring mice for changes in body weight over time. We determined a dose of injected PBMCs that allowed for GvHD to occur yet provided a window of opportunity for potential therapies to slow progression. When human natural T regulatory cells (nTregs) were co-injected with PBMCs in NOG mice, there was prolonged survival and a less rapid loss of body weight as compared to PBMCs alone. To create an NK cytotoxicity model, we transplanted human primary NK cells into NOG-hIL15 mice, which are NOG mice that constitutively produce human IL-15. We showed successful engraftment and proliferation of NK cells, with peak engraftment occurring 4-5 weeks post injection, and that these human primary NK cells were able to persist without signs of xenogeneic GvHD. Utilizing K562 tumor cells that express luciferase, we found these engrafted NK cells have fast and potent cytotoxic activity using IVIS imaging, resulting in elimination of tumor cells as compared to non-engrafted mice. Our results collectively suggest that the two in vivo models developed here will be valuable tools for investigating the clinical benefit of immune cell-based therapeutics.

Citation Format: Elizabeth McMichael, Utsav Jetley, Christopher Rudulier, Minasri Borah, Nicole Ganci, Vandhana Ragothaman, Ishina Balwani, Amanda Frain, Priya Pajanirassa, Yuko Miki, Jeffrey Jones, Troy Luster, Marie Keenan, Terina Martinez, Yong Zhang, Birgit Schultes. In vivo model development for immune cell-based therapeutics [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5574.

The effect of bilateral cardiac sympathetic denervation for refractory ventricular tachycardia in ischemic cardiomyopathy

Recent studies have shown that cardiac sympathetic denervation (CSD) is effective in the treatment of refractory ventricular tachyarrhythmia in patients with structural heart disease. This case report aimed to highlight the effect of bilateral CSD in suppressing treatment‐resistant ventricular tachycardia in patients with ischemic cardiomyopathy.

Impact of the type of electroanatomic mapping system on the incidence of cerebral embolism after radiofrequency catheter ablation of left atrial tachycardias

BACKGROUND

Left atrial tachycardias (ATs) often occur after left atrial ablation. The incidence of symptomatic and silent cerebral embolism after radiofrequency catheter ablation of left ATs and the impact of the type of 3-dimensional electroanatomic mapping (3D-EAM) system on the incidence of cerebral embolism remain unclear.

OBJECTIVES

This study aimed to investigate the incidence of cerebral embolism after a 3D-EAM system-guided left AT ablation procedure and compare that between the different 3D-EAM systems.

METHODS

We prospectively enrolled 59 patients who underwent left AT ablation and brain magnetic resonance imaging after the procedure: 30 were guided by the Rhythmia system (Boston Scientific, Marlborough, MA) and 29 by the CARTO system (Biosense Webster, Diamond Bar, CA) (groups R and C, respectively).

RESULTS

One transient ischemic attack occurred in group R, and no symptomatic embolism occurred in group C. Silent cerebral ischemic lesions (SCILs) were observed in 35 patients (59.3%), and group R had a significantly higher incidence of SCILs than did group C (86.2% vs 33.3%; P < .001). In multivariate analysis, group R and left atrial linear ablation were independent positive predictors of SCILs (odds ratio 12.822 and 8.668; P = .001 and P = .005). The incidence of bleeding complications was comparable between groups R and C (0% vs 3.3%; P = .508).

CONCLUSION

Group R exhibited a higher incidence of postablation cerebral embolism than did group C. The use of the high-resolution 3D-EAM system with a mini-basket catheter to guide radiofrequency ablation of left atrial macroreentrant tachycardias may markedly increase the risk of silent cerebral embolism. The present results require further validation in a randomized study.

Postablation cerebral embolisms in balloon-based atrial fibrillation ablation with periprocedural direct oral anticoagulants: A comparison between cryoballoon and HotBalloon ablation

INTRODUCTION

This prospective observational study aimed to investigate the incidence of symptomatic and silent cerebral embolisms after balloon-based ablation of atrial fibrillation (AF) in patients receiving periprocedural anticoagulation with direct oral anticoagulants (DOACs), and compare that between cryoballoon and HotBalloon ablation (CBA and HBA).

METHODS AND RESULTS

We enrolled 123 consecutive AF patients who underwent a balloon-based pulmonary vein isolation (PVI) and brain magnetic resonance (MR) imaging after the ablation procedure (CBA, n = 65; HBA, n = 58). The DOACs were continued in 62 patients throughout the periprocedural period and discontinued in 61 on the procedural day. Intravenous heparin was infused to maintain an activated clotting time of 300 to 400 seconds during the procedure. No symptomatic embolisms occurred in this series. Silent cerebral ischemic lesions (SCILs) were observed on MR imaging in 22 patients (17.9%), and the incidence of SCILs did not significantly differ between the CBA and HBA groups (21.5 vs 13.8%; P = 0.263). According to a multivariate logistic regression analysis, an older age was an independent positive predictor of SCILs (odds ratio, 1.062; 95% CI, 1.001-1.126; P = 0.046), but neither the balloon catheter type nor periprocedural continuation or discontinuation of the DOACs were significant predictors. The incidence of major and minor bleeding complications was comparable between the CBA and HBA groups (1.5 vs 0%, P = 0.528; 7.7 vs 5.2%, P = 0.424).

CONCLUSIONS

Both CBA and HBA of AF revealed a similar incidence of postablation cerebral embolisms. Elderly patients may be at a risk of SCILs after a balloon-based PVI with periprocedural DOAC treatment.

Imaging Differences between Neuromyelitis Optica Spectrum Disorders and Multiple Sclerosis: A Multi-Institutional Study in Japan

BACKGROUND AND PURPOSE

Both clinical and imaging criteria must be met to diagnose neuromyelitis optica spectrum disorders and multiple sclerosis. However, neuromyelitis optica spectrum disorders are often misdiagnosed as MS because of an overlap in MR imaging features. The purpose of this study was to confirm imaging differences between neuromyelitis optica spectrum disorders and MS with visually detailed quantitative analyses of large-sample data.

MATERIALS AND METHODS

We retrospectively examined 89 consecutive patients with neuromyelitis optica spectrum disorders (median age, 51 years; range, 16-85 years; females, 77; aquaporin 4 immunoglobulin G-positive, 93%) and 89 with MS (median age, 36 years; range, 18-67 years; females, 68; relapsing-remitting MS, 89%; primary-progressive MS, 7%; secondary-progressive MS, 2%) from 9 institutions across Japan (April 2008 to December 2012). Two neuroradiologists visually evaluated the number, location, and size of all lesions using the Mann-Whitney U test or the Fisher exact test.

RESULTS

We enrolled 79 patients with neuromyelitis optica spectrum disorders and 87 with MS for brain analysis, 57 with neuromyelitis optica spectrum disorders and 55 with MS for spinal cord analysis, and 42 with neuromyelitis optica spectrum disorders and 14 with MS for optic nerve analysis. We identified 911 brain lesions in neuromyelitis optica spectrum disorders, 1659 brain lesions in MS, 86 spinal cord lesions in neuromyelitis optica spectrum disorders, and 102 spinal cord lesions in MS. The frequencies of periventricular white matter and deep white matter lesions were 17% and 68% in neuromyelitis optica spectrum disorders versus 41% and 42% in MS, respectively (location of brain lesions, P < .001). We found a significant difference in the distribution of spinal cord lesions between these 2 diseases (P = .024): More thoracic lesions than cervical lesions were present in neuromyelitis optica spectrum disorders (cervical versus thoracic, 29% versus 71%), whereas they were equally distributed in MS (46% versus 54%). Furthermore, thoracic lesions were significantly longer than cervical lesions in neuromyelitis optica spectrum disorders (P = .001), but not in MS (P = .80).

CONCLUSIONS

Visually detailed quantitative analyses confirmed imaging differences, especially in brain and spinal cord lesions, between neuromyelitis optica spectrum disorders and MS. These observations may have clinical implications.

Application of The Paris System to atypical urine cytology samples: correlation with histology and UroVysion® FISH

OBJECTIVES

To evaluate whether atypical urine cytology cases may be stratified more objectively using The Paris System (TPS) and whether reclassified cases correlate with histology and UroVysion^® results.

METHODS

Atypical urine cytology cases subjected to UroVysion^® testing over a period of 6 years were reviewed. Each case was reclassified according to TPS and correlated with histology and UroVysion^® results.

RESULTS

A total of 91 cases were identified; 70.3% were reclassified as 'negative for high-grade urothelial carcinoma (HGUC)' and 14.3% as 'atypical urothelial cells (AUC)'. The histological correlation was available in 45 cases. In the 'negative for HGUC' category, 67.9% had no histological evidence of malignancy, but 17.9% were diagnosed as HGUC. In the 'AUC' category, histology revealed urothelial carcinoma in 70% of the cases (of these, 71.4% were high grade). There was no histological evidence of malignancy in 30% of cases; notably, all of which were from patients under surveillance. The sensitivity and specificity of UroVysion^® were 85.7% and 33.3% in the 'AUC' group and 62.5% and 100% in the 'negative for HGUC' group.

CONCLUSIONS

The Paris System is an objective template for reporting urine cytology specimens, and is particularly useful in identifying HGUC cases and refining the category of 'AUC'.

Higher CHADS2 score is associated with impaired coronary flow reserve: A study using phase contrast cine magnetic resonance imaging

BACKGROUND

The presence of coronary microvascular dysfunction (CMD) is an important prognostic marker for coronary artery disease (CAD) patients. The purpose of this study was to investigate whether the CHADS2 score is associated with CMD evaluated by magnetic resonance imaging (MRI).

MATERIALS AND METHODS

One hundred forty three patients with known or suspected CAD (mean age 70.3±9.5years) were enrolled. All patients did not have any significant coronary stenosis on X-ray coronary angiography (CAG) at the time of MRI acquisition. By using a 1.5T MRI scanner, breath-hold phase contrast cine MRI images of coronary sinus (CS) were obtained to assess the blood flow of CS both at rest and during adenosine triphosphate (ATP) infusion. Coronary flow reserve (CFR) was calculated as CS blood flow during ATP infusion divided by CS blood flow at rest. CMD was defined as CFR<2.5 according to a previous study. Patients were allocated to four groups based on the CHADS2 score (group1: CHADS2 score=0, group2: CHADS2 score=1; group3: CHADS2 score=2, and group4: CHADS2 score≥3).

RESULTS

Mean CFR was 2.81±0.95 (77.6±32.7mL/min at rest; 208.2±86.5mL/min during ATP infusion, p<0.001). Patients with higher CHAD2 score had lower CFR. In the multiple logistic regression analysis, CHADS2 score was independently associated with CFR (odds ratio=0.61, 95% confidence interval: 0.37-0.99, p=0.049).

CONCLUSIONS

Higher CHADS2 score was significantly associated with lower CFR evaluated by phase contrast cine MRI.

The Roles of the Secreted Phospholipase A2 Gene Family in Immunology

Within the phospholipase A₂ (PLA₂) family that hydrolyzes phospholipids to yield fatty acids and lysophospholipids, secreted PLA₂ (sPLA₂) enzymes comprise the largest group containing 11 isoforms in mammals. Individual sPLA₂s exhibit unique tissue or cellular distributions and enzymatic properties, suggesting their distinct biological roles. Although PLA₂ enzymes, particularly cytosolic PLA₂ (cPLA₂α), have long been implicated in inflammation by driving arachidonic acid metabolism, the precise biological roles of sPLA₂s have remained a mystery over the last few decades. Recent studies employing mice gene-manipulated for individual sPLA₂s, in combination with mass spectrometric lipidomics to identify their target substrates and products in vivo, have revealed their roles in diverse biological events, including immunity and associated disorders, through lipid mediator-dependent or -independent processes in given microenvironments. In this review, we summarize our current knowledge of the roles of sPLA₂s in various immune responses and associated diseases.

A potential pitfall of the modified 12 lead electrocardiogram (Mason-Likar modification) in catheter ablation of idiopathic ventricular arrhythmias originating from the outflow tract

AIMS

The Mason-Likar modified electrocardiogram (ML-ECG) can be interchanged with standard 12 lead ECG electrode positions (standard ECG) without affecting the diagnostic interpretation during sinus rhythm, but the morphological differences during ventricular arrhythmias have not been sufficiently evaluated. This study aimed to elucidate the morphological changes in the ML-ECG precordial leads.

METHODS AND RESULTS

In 53 consecutive patients with premature ventricular contractions predicted to originate from the outflow tract (OT-PVCs), the arrhythmias were analysed by those two ECG methods. The OT-PVC origin sites, which were predicted by currently published criteria with the respective ECG methods prior to catheter ablation, were compared with the successful ablation sites. Compared with the standard-ECG, S-waves in the ML-ECG became shallower in leads V1-4 (P < 0.05 in lead V1; P < 0.001 in leads V2-4), and pseudo-R-waves in lead V1 appeared in seven patients. The precordial leads transition zone shifted counter-clockwise in 18 patients in the ML-ECG. In leads I and aVL, the negative deflection amplitudes of the ML-ECG were greater than those of the standard ECG (P < 0.001), and polarity reversals in lead I appeared in 18 patients. The R-wave amplitudes in all ML-ECG inferior leads were greater than those in the standard-ECG leads (all for P < 0.001). Those changes had an effect on the diagnostic indexes for the localization, and the specificity of the criteria for the ML-ECG was poorer than that for the standard-ECG.

CONCLUSION

Great differences were found between those two ECG methods. Predicting OT-PVC origins by diagnostic criteria with the ML-ECG might result in a misdiagnosis and inefficient ablation.

Simultaneous immunostaining with anti-S100P and anti-SV40 antibodies revealed the origin of BK virus-infected decoy cells in voided urine samples

BACKGROUND

Methods for determining the origin of BK virus (BKV)-infected cells (decoy cells) in clinical urine samples have not been established although they could enhance the diagnosis of BKV infection in immunocompromised patients.

METHODS

We performed simultaneous immunostaining with anti-S100P (a urothelial marker) and anti-SV40 antibodies in 66 clinical urine samples exhibiting SV40 positivity and a decoy-cell appearance on Papanicolaou staining. The clinical voided urine samples included seven cases of renal transplantation, 47 cases of cancer therapy and 12 cases of non-neoplastic disease. SurePath(™) liquid-based cytology was used for the urine samples.

RESULTS

BKV-infected cells were categorized as SV40(+)/S100P(+) and SV40 (+)/S100p(-). SV40(+)/S100P(-) cells were found in 55 cases (83.4%); nine cases (13.6%) carried both SV40(+)/S100P(-) and SV40(+)/S100P(+) cells. The former were identified as BKV infection in renal tubules and the latter in both the renal tubules and urothelial epithelia. The remaining two cases (3.0%) had only SV40(+)/S100P(+) cells of urothelial origin.

CONCLUSION

Simultaneous immunostaining with anti-S100P and anti-SV40 is a useful method for determining the origin of BKV-infected cells in clinical urine samples from immunocompromised patients such as renal transplantation recipients.

Squamous-lined cyst of the pancreas: Radiological-pathological correlation

Pancreatic cystic lesions are increasingly being detected incidentally because of the increased use of cross-sectional imaging. Squamous-lined cysts of the pancreas (lymphoepithelial cyst, epidermoid cyst, and dermoid cyst) are rare cystic lesions lined with squamous epithelium. Distinguishing squamous-lined cysts from other cystic lesions of the pancreas is important to avoid unnecessary surgery, because squamous-lined cysts of the pancreas have no malignant potential. The purpose of this review is to describe findings on computed tomography and magnetic resonance imaging and the histopathological characteristics of squamous-lined cysts, and to summarize the key points of differential diagnosis for pancreatic cystic lesions.

Single institutional experience of the treatment of angiosarcoma of the face and scalp

OBJECTIVE

Angiosarcoma is a rare malignant neoplasm with a poor prognosis. A retrospective study was performed to accumulate radiotherapy (RT) data.

METHODS

Data from 17 patients with angiosarcoma of the face and scalp (AFS) who were treated with definitive RT between January 1999 and July 2011 were retrospectively analysed. The total radiation dose was 70 Gy, and the fractional doses were 2.0-2.5 Gy. Combined with RT, chemotherapy using docetaxel alone, recombinant interleukin-2 immunotherapy alone and both of these was performed in 10, 4 and 2 patients, respectively. Three patients underwent limited surgery before RT.

RESULTS

The response rate was 82%, and the median overall survival (OS) rate was 26 months. Locoregional relapse alone, distant metastasis alone and both of these were confirmed in 4, 5 and 4 patients, respectively. Patients treated with docetaxel showed a better prognosis (p=0.0477), a distant metastasis-free rate (p=0.0063) and a better in-field control rate, although the last was not statistically significant (p=0.1645).

CONCLUSION

Definitive RT combined with docetaxel chemotherapy provided an effective approach for treating AFS.

ADVANCES IN KNOWLEDGE

Since patients treated with chemoradiotherpy using docetaxel showed better OS and distant metastasis-free rates than those who did not receive docetaxel, it was warranted to continue use of docetaxel. In chemoradiotherapy at a dose of 70 Gy using docetaxel, 2-year in-field control rate was 67%.

LMTK3 is implicated in endocrine resistance via multiple signaling pathways

Resistance to endocrine therapy in breast cancer is common. With the aim of discovering new molecular targets for breast cancer therapy, we have recently identified LMTK3 as a regulator of the estrogen receptor-alpha (ERα) and wished to understand its role in endocrine resistance. We find that inhibition of LMTK3 in a xenograft tamoxifen (Tam)-resistant (BT474) breast cancer mouse model results in re-sensitization to Tam as demonstrated by a reduction in tumor volume. A whole genome microarray analysis, using a BT474 cell line, reveals genes significantly modulated (positively or negatively) after LMTK3 silencing, including some that are known to be implicated in Tam resistance, notably c-MYC, HSPB8 and SIAH2. We show that LMTK3 is able to increase the levels of HSPB8 at a transcriptional and translational level thereby protecting MCF7 cells from Tam-induced cell death, by reducing autophagy. Finally, high LMTK3 levels at baseline in tumors are predictive for endocrine resistance; therapy does not lead to alteration in levels, whereas in patient's plasma samples, acquired LMTK3 gene amplification (copy number variation) was associated with relapse while receiving Tam. In aggregate, these data support a role for LMTK3 in both innate (intrinsic) and acquired (adaptive) endocrine resistance in breast cancer.

Intratumoral concentration of estrogens and clinicopathological changes in ductal carcinoma in situ following aromatase inhibitor letrozole treatment

Background:

Estrogens have important roles in ductal carcinoma in situ (DCIS) of the breast. However, the significance of presurgical aromatase inhibitor treatment remains unclear. Therefore, we examined intratumoral concentration of estrogens and changes of clinicopathological factors in DCIS after letrozole treatment.

Methods:

Ten cases of postmenopausal oestrogen receptor (ER)-positive DCIS were examined. They received oral letrozole before the surgery, and the tumour size was evaluated by ultrasonography. Surgical specimens and corresponding biopsy samples were used for immunohistochemistry. Snap-frozen specimens were also available in a subset of cases, and used for hormone assays and microarray analysis.

Results:

Intratumoral oestrogen levels were significantly lower in DCIS treated with letrozole compared with that in those without the therapy. A great majority of oestrogen-induced genes showed low expression levels in DCIS treated with letrozole by microarray analysis. Moreover, letrozole treatment reduced the greatest dimension of DCIS, and significantly decreased Ki-67 and progesterone receptor immunoreactivity in DCIS tissues.

Conclusion:

These results suggest that estrogens are mainly produced by aromatase in DCIS tissues, and aromatase inhibitors potently inhibit oestrogen actions in postmenopausal ER-positive DCIS through rapid deprivation of intratumoral estrogens.

Androgen receptor in triple negative breast cancer

The clinical management of triple negative breast cancer (TNBC) is challenging due to the relatively aggressive biological behaviour and paucity of specific targeted therapy. A subset of TNBC patients has been reported to express androgen receptor (AR) in carcinoma cells and the manipulation of androgen signalling or AR targeted therapies have been proposed. However, the biological significance of AR in TNBC has remained relatively unknown. Therefore, this review aims to summarise the reported studies assessing the rates of AR positivity in TNBC patients and androgenic effects in TNBC cell lines. The rates of AR positivity among TNBC cases varied depending on the study population (0-53% of all TNBC patients). This difference among the reported studies may be largely due to the methodological differences of analysing AR. While the majority of cell line studies suggest that androgen increase proliferation and preliminary clinical studies suggest that AR antagonists improve the prognosis of AR positive TNBC patients, cell line transfection experiments and survival analyses of histological samples suggest that the presence of AR in tumour is either benign or predicts better survival. Therefore further translational investigations regarding the mechanisms of androgen action in TNBC are required to explain this discrepancy between clinical and basic studies.

Abstract P6-05-14: Estrogen-induced genes in ductal carcinoma in situ(DCIS): their comparison with invasive ductal carcinoma

It is well known that estrogens play important roles in both the pathogenesis and development of invasive ductal carcinoma (IDC) of human breast. However, molecular features of estrogen actions have remained largely unclear in pure ductal carcinoma in situ (pDCIS), regarded as a precursor lesion of many IDCs. This is partly due to the fact that gene expression profiles of estrogen-responsive genes have not been examined in pDCIS. Therefore, we first examined the profiles of estrogen-induced genes in estrogen receptor (ER)-positive pDCIS and DCIS (DCIS-c) and IDC (IDC-c) components of IDC cases (n = 4, respectively) by microarray analysis. Estrogen-induced genes identified in this study were tentatively classified into three different groups in the hierarchical clustering analysis, and 33% of the genes were predominantly expressed in pDCIS rather than DCIS-c or IDC-c cases. Among these genes, the status of MYB (c-MYB), RBBP7 (RbAp46) and BIRC5 (survivin) expression in carcinoma cells was significantly higher in ER-positive pDCIS(n = 53) than that in ER-positive DCIS-c (n = 27) or IDC-c (n = 27) by subsequent immunohistochemical analysis of the corresponding genes (P &lt; 0.0001, P = 0.03 and P = 0.0003, respectively). In particular, the status of c-MYB immunoreactivity was inversely (P = 0.006) correlated with Ki-67 in the pDCIS cases. These results suggest that expression profiles of estrogen-induced genes in pDCIS may be different from those in IDC, and c-MYB, RbAp46 and survivin may play particularly important roles among estrogen induced genes in ER-positive pDCIS.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P6-05-14.

Predictors of asymptomatic cerebral infarction associated with radiofrequency catheter ablation for atrial fibrillation using an irrigated-tip catheter

AIMS

Catheter ablation is a potentially curative treatment for atrial fibrillation (AF). However, complications such as ischaemic stroke are more frequent and more severe compared with ablation procedures for other arrhythmias. Irrigated-tip catheters have been reported to reduce the risk of stroke. The present study aimed to evaluate predictors of asymptomatic cerebral infarction (CI) after AF ablation using an irrigated-tip catheter.

METHODS AND RESULTS

A total of 70 consecutive AF patients who underwent catheter ablation were subjected to brain magnetic resonance imaging (MRI) 1 day after the procedure. In 10 (14.3%) of 70 patients, MRI revealed acute CI, but neither symptoms nor abnormal neurological findings were present in these patients. In univariate analysis, a history of persistent AF, left atrial dimension, presence of spontaneous echo contrast (SEC), procedure duration prior to heparin injection, and electrical cardioversion during the procedure differed significantly between the two groups, those with and without CI (P = 0.02, 0.05, 0.01, 0.01, and 0.05, respectively). Multivariate logistic regression analysis identified SEC [odds ratio (OR), 9.39; 1.60-55.2; P = 0.01] and procedure duration prior to heparin injection (OR, 1.19; 1.04-1.36; P = 0.01) as predictive of acute asymptomatic CI after AF ablation.

CONCLUSION

The presence of SEC and procedure duration prior to heparin injection are determinants of asymptomatic CI during AF ablation despite the use of an irrigated-tip catheter.

Carcinoembryonic antigen-related cell adhesion molecules as surrogate markers for EGFR inhibitor sensitivity in human lung adenocarcinoma

Background:

Lung adenocarcinoma (LADCA) patients with epidermal growth factor receptor (EGFR) mutations are in general associated with relatively high clinical response rate to EGFR-tyrosine kinase inhibitors (TKIs) but not all responded to TKI. It has therefore become important to identify the additional surrogate markers regarding EGFR-TKI sensitivity.

Methods:

We first examined the effects of EGFR-TKIs, gefitinib and erlotinib, upon cell proliferation of lung adenocarcinoma cell lines. We then evaluated the gene profiles related to EGFR-TKI sensitivity using a microarray analysis. Results of microarray analysis led us to focus on carcinoembryonic antigen-related cell adhesion molecule (CEACAM) family, CEACAM 3, 5, 6, 7, and 19, as potential further surrogate markers of EGFR-TKI sensitivity. We then examined the correlation between the status of CEACAM 3, 5, 6, 7, and 19 immunoreactivity in LADCA and clinicopathological parameters of individual cases.

Results:

In the cases with EGFR mutations, the status of all CEACAMs examined was significantly higher than that in EGFR wild-type patients, but there were no significant differences in the status of CEACAMs between TKI responder and nonresponder among 22 patients who received gefitinib therapy. However, among 115 EGFR mutation-negative LADCA patients, both CEACAM6 and CEACAM3 were significantly associated with adverse clinical outcome (CEACAM6) and better clinical outcome (CEACAM3).

Conclusion:

CEACAMs examined in this study could be related to the presence of EGFR mutation in adenocarcinoma cells but not represent the effective surrogate marker of EGFR-TKI in LADCA patients. However, immunohistochemical evaluation of CEACAM3/6 in LADCA patients could provide important information on their clinical outcome.

Immunohistochemical analysis of gastrin-releasing peptide receptor (GRPR) and possible regulation by estrogen receptor βcx in human prostate carcinoma

Gastrin-releasing peptide (GRP) belongs to the family of bombesin-like peptides. GRP was demonstrated to stimulate the proliferation and invasiveness of androgen-independent prostate carcinoma. GRP mediates its action through the membrane-bound receptor, GRP receptor (GRPR), which is characterized by a high-affinity binding for both GRP and bombesin. In human prostate cancer tissue, GRPR mRNA was reported to be detectable in more than 90% but its immunolocalizaition has not been reported. Therefore, in this study we immunolocalized GRPR in 51 human prostate cancer cases and correlated the findings with several clinicopathological parameters in order to better understand the function and regulation of GRPR in human prostate cancer. GRPR was immnolocalized in carcinoma cells and their values were significantly associated with Gleason score and immunoreactivity of estrogen receptor βcx (ERβcx) that is one of splicing variants of ligand dependent transcription factor, ERβ, and considered to be prognostic factor of prostate cancer patients. The amounts of GRPR and ERβcx mRNA in three prostate cancer cell lines PC-3, DU-145 and LNCaP evaluated by quantitative RT-PCR (qPCR) analysis were also significantly correlated. In addition, we established stable transformants of prostate carcinoma cell line PC-3 introduced with ERβcx, and confirmed that GRPR mRNA was induced in ERβcx over-expressing PC-3 cells by qPCR analysis. These results also suggest that ERβcx contributes to prostate cancer development possibly through mediating GRPR expression in carcinoma cells.