Spatial intratumor heterogeneity of programmed death-ligand 1 expression predicts poor prognosis in resected non-small cell lung cancer.

OBJECTIVE: We quantified the pathological spatial intratumor heterogeneity (ITH) of programmed death-ligand 1 (PD-L1) expression and investigated its relevance to patient outcomes in surgically resected non-small cell lung carcinoma (NSCLC). MATERIALS AND METHODS: This study enrolled 239 consecutive surgically resected NSCLC specimens of pathological stage IIA-IIIB. To characterize the spatial ITH of PD-L1 expression in NSCLC tissues, we developed a mathematical model based on texture image analysis and determined the spatial heterogeneity index of PD-L1 (SHIP) for each tumor. The correlation between the SHIP values and clinicopathological characteristics, including prognosis, was analyzed. Furthermore, an independent cohort of 70 cases was analyzed for model validation. RESULTS: Clinicopathological analysis showed correlations between high SHIP values and histological subtype (squamous cell carcinoma, p < .001) and vascular invasion (p = .004). Survival analysis revealed that patients with high SHIP values presented a significantly worse recurrence-free rate than those with low SHIP values (5-year RFS 26.3% vs 47.1%, p < .005). The impact of SHIP on cancer survival rates was verified through validation in an independent cohort. Moreover, high SHIP values were significantly associated with tumor recurrence in squamous cell carcinoma (5-year RFS 29.2% vs 52.8%, p < .05) and adenocarcinoma (5-year RFS 19.6% vs 43.0%, p < .01). Moreover, we demonstrated that a high SHIP value was an independent risk factor for tumor recurrence. CONCLUSIONS: We presented an image analysis model to quantify the spatial ITH of protein expression in tumor tissues. This model demonstrated that the spatial ITH of PD-L1 expression in surgically resected NSCLC predicts poor patient outcomes.

Impact of central nervous system metastasis after complete resection of lung adenocarcinomas harboring common EGFR mutation - A real-world database study in Japan: The CReGYT-01 EGFR study.

OBJECTIVES: To clarify the impact of central nervous system (CNS) metastasis on performance status (PS) at relapse, on subsequent treatment(s), and on survival of patients with lung adenocarcinoma harboring common epidermal growth factor receptor (EGFR) mutation. METHODS: We conducted the multicenter real-world database study for patients with radical resections for lung adenocarcinomas between 2015 and 2018 at 21 centers in Japan. EGFR mutational status was examined at each center. RESULTS: Of 4181 patients enrolled, 1431 underwent complete anatomical resection for lung adenocarcinoma harboring common EGFR mutations. Three-hundred-and-twenty patients experienced disease relapse, and 78 (24%) had CNS metastasis. CNS metastasis was significantly more frequent in patients with conventional adjuvant chemotherapy than those without (30% vs. 20%, P = 0.036). Adjuvant chemotherapy did not significantly improve relapse-free survival at any pathological stage (adjusted hazard ratio for stage IA2-3, IB, and II-III was 1.363, 1.287, and 1.004, respectively). CNS metastasis did not affect PS at relapse. Subsequent treatment, mainly consisting of EGFR-tyrosine kinase inhibitors (TKIs), could be equally given in patients with or without CNS metastasis (96% vs. 94%). Overall survival after relapse was equivalent between patients with and without CNS metastasis. CONCLUSION: The efficacy of conventional adjuvant chemotherapy may be limited in patients with lung adenocarcinoma harboring EGFR mutations. CNS metastasis is likely to be found in practice before deterioration in PS, and may have little negative impact on compliance with subsequent EGFR-TKIs and survival after relapse. In this era of adjuvant TKI therapy, further prospective observational studies are desirable to elucidate the optimal management of CNS metastasis.

EGFR mutation impacts recurrence in high-risk early-stage lung adenocarcinoma in the IASLC grading system.

INTRODUCTION: The developments of perioperative treatments for patients with high-risk early-stage lung cancer are ongoing, however, real-world data and evidence of clinical significance of genetic aberration are lacking in this population. This study aimed to identify patients with early-stage lung adenocarcinoma at high risk for recurrence based on pathological indicators of poor prognosis, including the International Association for the Study of Lung Cancer (IASLC) grade, and elucidate the prognostic impact of epidermal growth factor receptor mutation (EGFRm) status. METHODS: This retrospective study included 494 consecutive patients who underwent complete resection for pathological stage I lung adenocarcinoma between 2011 and 2016. The patients were evaluated for EGFRm and IASLC grade. Multivariable analysis was used to identify pathological factors for poor prognosis associated with recurrence-free survival (RFS) and overall survival (OS). Patients with any one of these factors were classified into the high-risk group. The prognostic impact of EGFRm was evaluated using RFS, OS, and cumulative recurrence proportion. RESULTS: Multivariable analysis for RFS and OS revealed that IASLC grade 3, pathological invasion size>2 cm, and presence of lymphovascular invasion were indicators of poor prognosis. EGFRm-positive patients had a higher incidence of all types of recurrence, including central nervous system (CNS) metastasis and distant metastasis in high-risk group, but not in low-risk group. CONCLUSIONS: This study provides evidence that patients with EGFRm-positive stage I lung adenocarcinoma in the high-risk group have an increased risk of recurrence, including CNS metastasis. These findings highlight the need for development of adjuvant treatment in this population.

Diagnostic Value of Nodal Staging of Lung Cancer With Usual Interstitial Pneumonia Using PET.

BACKGROUND: Preoperative staging of lymph node metastasis in patients with usual interstitial pneumonia (UIP) and non-small cell lung cancer (NSCLC) is difficult because inflammation can lead to false-positive imaging findings and clinical upstaging. We aimed to evaluate the accuracy of computed tomography (CT) and positron emission tomography (PET)/CT in nodal staging of NSCLC in patients with and without UIP. METHODS: Between November 2016 and June 2018, 198 patients underwent both preoperative CT and PET/CT and anatomic lung resection with mediastinal nodal dissection at our institute. Diagnosis of interstitial pneumonia (IP) was based on the presence of UIP or probable UIP pattern on CT. We retrospectively evaluated the diagnostic performance of PET/CT in nodal staging of NSCLC in patients with and without IP, with or without 18F-fluorodeoxyglucose (FDG) uptake in the lung. RESULTS: The sensitivity, specificity, and accuracy for nodal staging were 36%, 94%, and 77%, respectively, in patients without IP and 25%, 89%, and 73%, respectively, in those with IP. Of 49 patients with IP, 23 had FDG uptake in the lung. The sensitivity, specificity, and accuracy were 13%, 93%, and 65%, respectively, in patients with IP with FDG uptake and 50%, 86%, and 81%, respectively, in those without FDG uptake. CONCLUSIONS: We showed that the diagnostic performance of PET/CT in patients with IP was lower than that in patients without IP. Furthermore, the accuracy of nodal staging in patients with NSCLC and IP with FDG uptake was further decreased.

18F-fluorodeoxyglucose uptake in PET is associated with the tumor microenvironment in metastatic lymph nodes and prognosis in N2 lung adenocarcinoma.

Positron emission tomography is a useful technique for diagnosing lymph node (LN) metastasis. This study aimed to elucidate the association between fluorodeoxyglucose accumulation and the microenvironment in metastatic LNs in lung adenocarcinoma. We retrospectively analyzed 62 patients with surgically resected pathological N2 lung adenocarcinoma who underwent preoperative PET. The maximum standardized uptake value (SUVmax ) in the metastatic LNs was measured. Lymph node specimens were immunohistochemically analyzed for CD8+ , FoxP3+ , and CD79a+ lymphocytes, CD204+ tumor-associated macrophages (TAMs), and alpha-smooth muscle actin-positive cancer-associated fibroblasts (αSMA+ CAFs). We compared the clinicopathologic and immunohistochemical characteristics between two groups with high and low LN SUVmax . Using novel 3D hybrid spheroid models, we investigated the change in invasiveness of cancer cells in the presence of CAFs. In the multivariate analyses, LN SUVmax was an independent prognostic factor. The overall survival in the LN SUVmax high group was significantly worse than in the low group (P = .034). In the LN SUVmax high group, metastatic cancer cell invasion of extranodal tissue was more frequent (P = .005) and the number of CD204+ TAMs and αSMA+ CAFs in metastatic LNs was significantly higher than in the low group (P < .001 and P = .002, respectively). Hybrid spheroid models revealed that cancer cells coexisting with CAFs were more invasive than those without CAFs. Our results indicated a strong association between LN SUVmax and poor prognosis in patients with N2 lung adenocarcinoma. Moreover, LN SUVmax was suggested to be associated with the presence of tumor-promoting stromal cells in metastatic LNs.

Prognostic impact of extranodal extension in patients with pN1-N2 lung adenocarcinoma.

PURPOSE: Lymph node involvement is one of the important prognostic factors of patients with lung adenocarcinoma. In the tumor, node, and metastasis classification, lymph node involvement is categorized only according to the anatomical station and not the involvement pattern. The aim of this study was to investigate which morphological pattern of lymph node involvement affects the prognosis of patients with surgically resected lung adenocarcinoma. METHODS: We retrospectively reviewed 168 consecutive patients who underwent surgical resection for primary lung adenocarcinoma with lymph node involvement. The morphological patterns of lymph node involvement (tumor area, number of metastatic lymph nodes, presence of necrosis, and extranodal extension) were histologically examined. The relationships between the patterns of lymph node involvement, clinicopathological features, and survival of patients were analyzed. RESULTS: Eighty patients had N1 disease, and 88 patients had N2 disease. Univariate analysis revealed that invasive size, history of adjuvant chemotherapy, and presence of extranodal extension were significant prognostic factors in N1 patients, and vascular invasion, pleural invasion, presence of epidermal growth factor receptor mutation, history of adjuvant chemotherapy, and presence of extranodal extension were significant prognostic factors in N2 patients. In a bivariate analysis including other clinicopathological factors and patterns of lymph node involvement, the presence of extranodal extension was significantly associated with poor 3-year overall and recurrence-free survival of both N1 and N2 patients. CONCLUSIONS: In patients who underwent surgical resection for lung adenocarcinoma with lymph node involvement, the extranodal extension was the most important prognostic factor among morphological lymph node involvement patterns.

High-resolution ESR study of the H...CH3, H...CHD2, D...CH2D, and D...CD3 radical pairs in solid argon.

High-resolution electron spin resonance (ESR) spectra of radical pairs of a hydrogen atom that coupled with a methyl radical (H...CH3, H...CHD2, D...CH2D, and D...CD3) were observed for X-ray irradiated solid argon containing selectively deuterium-labeled methanes, CH4, CH2D2, and CD4, at 4.2 K. The double-quartet 1H-hyperfine (hf) splittings of ca. 26 and 1.16 mT at the Deltam(s) = +/-1 and Deltam(s) = +/-2 transitions, which are one-half of the isotropic 1H-hf splittings of an isolated H-atom and a CH3 radical, were attributed to the H...CH3 pair. The 1H-hf splittings at the Deltam(s) = +/-1 transition were further split by the fine structure (fs) due to the electron dipole-dipole coupling. Because of the high-resolution spectra, three different sets of the fs splitting, d, are clearly resolved in the spectra of both the H...CH3 and the D...CD3 pairs. The separation distance (inter-spin distance), R, between the H-atom and the CH3 radical being in pairs was evaluated from the d values based on a point-dipole interaction model. For the case of the H...CH3 pair, the observed d values of 4.2, 4.9, and 5.1 mT yield the respective separations, R = 0.87, 0.83, and 0.82 nm, to probe the trapping site of the pair in an Ar crystalline lattice (fcc). For the pair with R = 0.87 nm, for example, we propose that the CH3 radical occupies a substitutional site and the counter H-atom occupies either the interstitial tetrahedral sites directed away from the CH3 radicals by a distance of 0.87 nm or the interstitial octahedral sites by a distance of 0.88 nm. When a mixture of CH4 and CD4 in a solid Ar matrix was irradiated, only two different radical pairs, H...CH3 and D...CD3, were observed. This result clearly demonstrates that the hydrogen atom and methyl radicals, which undergo a pairwise trapping, can originate from the same methane molecule.

ESR and theoretical studies of trimer radical cations of coronene.

Highly resolved ESR spectra of monomer, dimer and trimer radical cations of coronene (C24H12) were observed at room temperature for a solution of 1,1,1,3,3,3-hexafluoro-2-propan-2-ol (HFP) containing thallium(III) trifluoroacetate as oxidant. The spectra consisting of multiple lines with isotropic 1H-hyperfine splitting (hfs) constants of 0.0766 mT (24H) and 0.013 mT (6H) were attributable to a mixture of the dimer with the trimer radical cations, (C24H12)2+ and (C24H12)3+. For (C24H12)2+, the 1H-hfs constant agreed well with the reported value, 0.077 mT. However, for (C24H12)3+, the values were significantly different from the reported ones, 0.117 mT (12H) and 0.020 mT (24H), by Ohya Nishiguchi et al. [H. Ohya-Nishiguchi, H. Ide, N. Hirota, Chem. Phys. Lett. 66 (1979) 581], but rather similar to those reported by Willigen et al. [H. van Willigen, E. De Boer, J.T. Cooper, W.F. Forbes, J. Chem . Phys. 49 (1968) 1190]. In conflict with Willigen's report, however, no ESR line broadening which has been ascribed to a low stationary concentration of (C24H12)3+ was detected. Based on ab initio MO calculations for benzene as a compact model of C24H12, the structure of (C24H12)3+ was investigated in terms of the observed 1H-hfs constants. A staggered sandwich C(2v) structure was suggested being at the "global" minimum for the benzene trimer cation. In the structure, the unpaired electron spin is predominantly localized to the central ring, which is qualitatively in agreement with the previous ESR results of (C24H12)3+ by Ohya-Nishiguchi et al. In addition, as a "local" minimum, the benzene trimer was indicated to have a slipped sandwich Cs structure, which is less stable by ca. 19 kJ mol(-1) than the "global" minimum. In this structure, the unpaired electron spin was nearly equally distributed on both the central and one of the two side C24H12 molecules. The observed 1H-hfs constants were possibly attributable to the (C24H12)3+ cation with the analogous slipped sandwich Cs structure.