Long-Term Results of a Multi-Institutional Study of Dynamic Tumor Tracking-Stereotactic Body Radiotherapy for Lung Tumors

PURPOSE/OBJECTIVE(S)

We had conducted a multi-institutional phase II study to evaluate the safety and efficacy of dynamic tumor tracking-stereotactic body radiotherapy (DTT-SBRT) for lung tumors. The primary endpoint was 2-year local control, which was reported to be 95.2%. After the initial evaluation of the primary endpoint, the study was extended as an observational study which was designed to evaluate 5-year survival and late toxicities. We present the long-term results of DTT-SBRT for lung tumors.

MATERIALS/METHODS

The main eligibility criteria for the study were as follows: (1) primary or metastatic lung cancer with a diameter of 5 cm or less, and up to 3 lesions without any extrapulmonary lesions; (2) ineligibility to standard surgery, or patient's refusal of surgery; (3) ECOG-PS of 0 to 2; and (4) expected range of respiratory motion of 10 mm or more. The study included 48 patients from four institutions with the median age of 80 years (range, 49-90 years). Forty-two patients had primary non-small-cell lung cancer, and 6 patients had metastatic lung tumors. Forty-eight tumors (median diameter, 23.5 mm; range, 5-47 mm) in 48 patients were targeted for DTT-SBRT using a gimbal-mounted linear accelerator. Prior to treatment planning, spherical gold markers were placed around the tumor to detect internal tumor motion using fluoroscopy. The prescribed dose was 50 Gy in four fractions. Treatment beams were delivered with DTT according to a 4D model that predicts internal tumor motion with abdominal wall motion. DTT-SBRT was successfully delivered to all but one patient who had poor correlation between abdominal wall and tumor motion.

RESULTS

Median follow-up period at data cutoff was 5.0 years (interquartile range, 3.1-6.3 years). Twenty-nine patients died; the causes of death were cancer-specific in 10 patients, comorbidity in 14 patients (pulmonary disease, renal failure, cerebral infarction, other malignancies, etc.), and unknown in 5 patients without cancer recurrence. Overall survival at 5 years was 51.5% (95% confidence interval [CI], 36.5-64.6%). Progression-free survival and local control at 5 years were 41.0% (95% CI, 27.0-54.5%) and 92.6% (95% CI, 78.7-97.6%), respectively. There were no grade 4-5 toxicities. One patient (2%) developed grade 3 radiation pneumonitis at 3 months. Grade 2 toxicities were observed in 9 patients (19%), including dyspnea, radiation pneumonitis, pleural effusion, rib fracture, and dermatitis.

CONCLUSION

Dynamic tumor tracking SBRT achieved the long-term efficacy with low incidence of severe toxicities in lung tumors with respiratory motion. In this elderly patient cohort, non-cancer deaths were observed more than cancer-specific deaths.

Major Cardiovascular Events after Chemoradiotherapy with or without Durvalumab in Patients with Stage III Non-Small Cell Lung Cancer: Supplementary Analysis

PURPOSE/OBJECTIVE(S)

RTOG 0617 showed that cardiac events are relatively common after high-dose thoracic radiotherapy. The aim of this study was to investigate the incidence and risk of major cardiovascular events (MACE) after concurrent chemoradiotherapy (CCRT) with or without durvalumab in patients with stage III non-small cell lung cancer (NSCLC) using the data from a multi-institutional study in Japan.

MATERIALS/METHODS

Patients who received CCRT for stage III NSCLC between July 2018 and July 2019 were enrolled in a multi-institutional study in Japan. MACE was defined as follows: symptomatic pericardial effusion, acute coronary syndrome, pericarditis, significant arrhythmia, and heart failure. The cumulative incidence of MACE, accounting for death as a competing risk, was calculated. Pre-existing coronary heart disease (CHD) included coronary artery disease, congestive heart failure, peripheral vascular disease, stroke, and extensive coronary artery calcification. The association between patient/treatment-related factors and MACE was assessed by multivariate analysis.

RESULTS

Among 178 patients with a median follow-up period of 42.5 months, 13 patients developed MACEs. The 3-year cumulative incidence of MACE was 6.9% (95% confidence interval [CI], 4.0-11.9%). Univariate analysis showed that female sex and mean heart dose (MHD) were marginally associated (3-year cumulative incidence, male 5.6% vs. female 12.1%; P = 0.12; MHD ≥ 6.3 Gy 4.8% vs. < 6.3 Gy 9.1%; P = 0.13), and pre-existing CHD was significantly associated with an increased risk of MACE (no CHD 4.3% vs. CHD 16.8%; P = 0.026). Consolidation durvalumab was not associated with an increased risk of MACE (no durvalumab 5.2% vs. durvalumab 7.4%; P = 0.89). Multivariate analysis showed that pre-existing CHD was significantly associated with MACE (hazard ratio, 4.22; 95% CI, 1.30-13.7; P = 0.016).

CONCLUSION

The incidence of MACE based on the real-world data in Japan was lower than previously reported. Pre-existing CHD was associated with an increased risk of MACE after CCRT in patients with stage III NSCLC, whereas the administration of consolidation durvalumab was not associated with an increased risk of MACE.

Real-World Study of Overall Survival in Patients with Stage III Non-Small Cell Lung Cancer Treated with Chemoradiotherapy with or without Durvalumab and an Exploratory Analysis of Effective Radiation Dose to the Immune Cells

PURPOSE/OBJECTIVE(S)

To investigate the real-world data on overall survival (OS) in patients with stage III non-small cell lung cancer (NSCLC) treated with concurrent chemoradiotherapy (CCRT) with or without consolidation durvalumab, and to perform an exploratory analysis on effective radiation dose to the immune cells (EDIC).

MATERIALS/METHODS

In our multi-institutional retrospective study, patients who received CCRT between July 2018 and July 2019 for stage III NSCLC in Japan were investigated. EDIC was estimated using mean lung dose, mean heart dose, body volume, body mean dose, and body weight, as reported in the secondary analysis of RTOG 0617. The cut-off value of EDIC was calculated using the maximally selected log-rank statistics.

RESULTS

One hundred and seventy-eight patients were eligible for the analysis (136 patients, CCRT with consolidation durvalumab [CCRT+D] cohort; 42 patients, CCRT cohort). The median follow-up period was 42.5 months. Three-year OS rates were 59.8% in the overall cohort: 60.5% in the CCRT+D cohort, and 58.0% in the CCRT cohort with no significant difference (hazard ratio [HR], 0.76; 95% confidence interval [CI], 0.45-1.27; P = 0.29). Univariate analysis showed that ECOG-PS, smoking history, histology, EGFR mutational status, gross tumor volume and EDIC were significantly associated with OS. Multivariate analysis showed that ECOG-PS 2, gross tumor volume ≥ 57 cm3 and EDIC ≥ 4.4 Gy were associated with poor OS. Among 21 EGFR-mutated patients, 3 year-OS rates were 64.7% in the CCRT+D cohort and 100% in the CCRT cohort, while 3 year-OS rates were 68.8% and 58.7% among 90 EGFR wild-type patients. Three-year OS rates were 64.6% and 47.6% for EDIC < 4.4 Gy and EDIC ≥ 4.4 Gy in the overall cohort (HR, 1.82; 95% CI, 1.14-2.90; P = 0.015). In the subgroup analysis, 66.3% vs. 44.4% in the CCRT+D cohort (HR, 2.01; 95% CI, 1.17-3.47; P = 0.016), and 59.0% vs. 56.1% in the CCRT cohort (HR, 1.20; 95% CI, 0.48-3.01; P = 0.70), respectively.

CONCLUSION

Our real-world data in Japan showed that there was no significant difference in OS between the CCRT+D cohort and the CCRT cohort. High EDIC could be a risk for poor OS in patients treated with CCRT and consolidation durvalumab compared with those treated with CCRT.

P103 Heart failure with preserved ejection fruction defines the progression of abnormal brain aging: a prospective study of young-old hypertensive patients

Funding Acknowledgements

Ministry of Health, Labor and Welfare (MHLW) Geriatrics and Gelontorogy sponsored research funds

Background & purpose: Recently, many longitudinal studies have shown that heart failure with reduced ejection fraction (HFrEF) is associated with various types of brain abnormalities: cerebral micro-bleeding, atrophy, or pathologic degeneration (white matter hyperintensity; WMH). These brain abnormalities are known to increase with aging and to be closely associated with cognitive impairment. Heart failure with preserved ejection fraction (HFpEF) also increases with aging, but there have been few longitudinal studies to address the relationship between HFpEF and brain abnormalities. Thus, this longitudinal study aimed to clarify this relationship by focusing on WMH volume.

METHODS

The participants were 111 well-controlled hypertensive patients aged between 65 and 75 years with normal LV contraction and no history of symptomatic heart failure, ischemic heart disease, atrial fibrillation, stroke, or cognitive dysfunction. The participants were classified into 3 groups: Low E/e", E/e" &lt; 8; Middle E/e", 8≤ E/e" ≤ 15; and High E/e", E/e" &gt; 15. WMH volume was quantified on brain magnetic resonance imaging using analytical software.

RESULTS

During the mean 2.6 ± 1.0-year follow-up period, the rate of increase of WMH volume was significantly higher in the high E/e" group (1.1 ± 1.2 mL/year) than in the low E/e" group (0.30 ± 0.78 mL/year; P = 0.0238). Linear regression analysis including other confounders showed that the only positive association was between the rate of increase of WMH volume and the E/e" ratio (beta- coefficient = 0.225, P = 0.018).

CONCLUSION

The severity of LV diastolic dysfunction is positively correlated with increasing WMH volume.

Abstract P103 Figure. The rates of increase of WMH volumes

P768Cardiopulmonary exercise testing for assessing frailty status in stable elderly patients with heart failure

Introduction

Frailty is a syndrome associated with aging that produces subclinical dysfunction across multiple organ systems and leads to increased risk of mortality. The Kihon Checklist (KCL) was developed by the Japanese Ministry of Health, Labor and Welfare to identify older persons in need of care; it is a reliable tool for predicting general frailty in older adults. There is little information about the relationship between frailty status and exercise capacity.

Purpose

To investigate whether cardiopulmonary exercise testing (CPX) parameters are associated with frailty in stable elderly patients with heart failure (HF).

Methods

Ninety-two stable elderly patients with HF were evaluated by using CPX and the total KCL (t-KCL). A t-KCL score of 0–3 was classified as robust, 4–7 as pre-frail, and ≥8 as frail. Diagnostic performance (DP) -plot analysis was used to assess the utility of CPX parameters to distinguish between the presence and absence of frailty.

Results

Mean age, left ventricular ejection fraction, plasma brain natriuretic peptide, peak work rate (WR), peak VO2, and t-KCL score were 81.7 years, 57.8%, 182 pg/mL, 49.6 W, 13.2 mL/kg/min, and 10.7, respectively. t-KCL score was significantly correlated with peak VO2 (r=−0.53, p<0.001) and peak WR (r=−0.63, p<0.001). In the patients with frailty (n=63), peak WR was significantly lower than that in patients without frailty (n=29; 40.8 and 71.0 W, respectively, p<0.001). Multivariate analysis revealed that peak WR was the only significant independent predictor of frailty (β=−0.111, p<0.001). In the DP-plot analysis, a cut-off value for peak WR of 51.9 W was the best predictor of frailty (accuracy; 0.706, Figure).

Cut-off value for peak WR

Conclusions

Frailty status was significantly associated with peak WR in stable elderly patients with HF. CPX may be useful for assessing frailty status in stable elderly patients with HF.

Further optimization of the M5 NAM MLPCN probe ML375: tactics and challenges

This Letter describes the continued optimization of the MLPCN probe ML375, a highly selective M5 negative allosteric modulator (NAM), through a combination of matrix libraries and iterative parallel synthesis. True to certain allosteric ligands, SAR was shallow, and the matrix library approach highlighted the challenges with M5 NAM SAR within in this chemotype. Once again, enantiospecific activity was noted, and potency at rat and human M5 were improved over ML375, along with slight enhancement in physiochemical properties, certain in vitro DMPK parameters and CNS distribution. Attempts to further enhance pharmacokinetics with deuterium incorporation afforded mixed results, but pretreatment with a pan-P450 inhibitor (1-aminobenzotriazole; ABT) provided increased plasma exposure.

Development of a highly potent, novel M5 positive allosteric modulator (PAM) demonstrating CNS exposure: 1-((1H-indazol-5-yl)sulfoneyl)-N-ethyl-N-(2-(trifluoromethyl)benzyl)piperidine-4-carboxamide (ML380)

A functional high throughput screen identified a novel chemotype for the positive allosteric modulation (PAM) of the muscarinic acetylcholine receptor (mAChR) subtype 5 (M₅). Application of rapid analog, iterative parallel synthesis efficiently optimized M₅ potency to arrive at the most potent M₅ PAMs prepared to date and provided tool compound 8n (ML380) demonstrating modest CNS penetration (human M₅ EC₅₀ = 190 nM, rat M₅ EC₅₀ = 610 nM, brain to plasma ratio (K_p) of 0.36).

Discovery, synthesis and characterization of a highly muscarinic acetylcholine receptor (mAChR)-selective M5-orthosteric antagonist, VU0488130 (ML381): a novel molecular probe

Of the five G-protein-coupled muscarinic acetylcholine receptors (mAChRs; M1-M5), M5 is the least explored and understood due to a lack of mAChR subtype-selective ligands. We recently performed a high-throughput functional screen and identified a number of weak antagonist hits that are selective for the M5 receptor. Here, we report an iterative parallel synthesis and detailed molecular pharmacologic profiling effort that led to the discovery of the first highly selective, central nervous system (CNS)-penetrant M5-orthosteric antagonist, with sub-micromolar potency (hM5 IC50=450 nM, hM5 Ki=340 nM, M1-M4 IC50>30 μM), enantiospecific inhibition, and an acceptable drug metabolism and pharmacokinetics (DMPK) profile for in vitro and electrophysiology studies. This compound will be a powerful tool and molecular probe for the further investigation into the role of M5 in addiction and other diseases.

Discovery of the first M5-selective and CNS penetrant negative allosteric modulator (NAM) of a muscarinic acetylcholine receptor: (S)-9b-(4-chlorophenyl)-1-(3,4-difluorobenzoyl)-2,3-dihydro-1H-imidazo[2,1-a]isoindol-5(9bH)-one (ML375)

A functional high throughput screen and subsequent multidimensional, iterative parallel synthesis effort identified the first muscarinic acetylcholine receptor (mAChR) negative allosteric modulator (NAM) selective for the M5 subtype. ML375 is a highly selective M5 NAM with submicromolar potency (human M5 IC50 = 300 nM, rat M5 IC50 = 790 nM, M1-M4 IC50 > 30 μM), excellent multispecies PK, high CNS penetration, and enantiospecific inhibition.

Suppressive effects of a novel CC chemokine receptor 4 antagonist on Th2 cell trafficking in ligand- and antigen-induced mouse models

CC chemokine receptor 4 (CCR4) has been implicated as a preferential marker for T helper type 2 (Th2) cells, and is believed to be involved in the pathology of allergic diseases by controlling Th2 cell trafficking into inflamed tissues. The objective of the study was to characterize the pharmacological properties of E0001-163, a novel CCR4 antagonist. E0001-163 was tested in both in vitro chemotaxis assays as well as in vivo mouse models of CCR4 ligand-induced air pouch and antigen-induced airway inflammation by utilizing in vitro-polarized Th2 cells. In vitro, E0001-163 inhibited migratory response of human Th2-polarized cells to CCL22, a CCR4 ligand, with an IC50 value of 11.9 nM. E0001-163 significantly suppressed CCL22-induced Th2 cell trafficking into mouse air pouch in a dose-dependent manner at doses of 3 and 10mg/kg, suggesting that E0001-163 has an inhibitory effect on CCR4-mediated T cell trafficking in vivo. In addition, E0001-163 partially decreased Th2 cell trafficking and the level of IL-4 in the lungs in Th2-tansferred and ovalbumin (OVA)-challenged mice. T cell trafficking involves multiple chemokine receptors both in acute and chronic phases, and our findings suggest that CCR4, together with other chemokine receptors, may be involved in Th2 cell trafficking under disease conditions.

Studies of the humoral factors produced by layered chondrocyte sheets

The authors aimed to repair and regenerate articular cartilage with layered chondrocyte sheets, produced using temperature-responsive culture dishes. The purpose of this study was to investigate the humoral factors produced by layered chondrocyte sheets. Articular chondrocytes and synovial cells were harvested during total knee arthroplasty. After co-culture, the samples were divided into three groups: a monolayer, 7 day culture sheet group (group M); a triple-layered, 7 day culture sheet group (group L); and a monolayer culture group with a cell count identical to that of group L (group C). The secretion of collagen type 1 (COL1), collagen type 2 (COL2), matrix metalloproteinase-13 (MMP13), transforming growth factor-β (TGFβ), melanoma inhibitory activity (MIA) and prostaglandin E2 (PGE2) were measured by enzyme-linked immunosorbent assay (ELISA). Layered chondrocyte sheets produced the most humoral factors. PGE2 expression declined over time in group C but was significantly higher in groups M and L. TGFβ expression was low in group C but was significantly higher in groups M and L (p<0.05). Our results suggest that the humoral factors produced by layered chondrocyte sheets may contribute to cartilaginous tissue repair and regeneration.