Exclusion of emphysematous lung from dose-volume estimates of risk improves prediction of radiation pneumonitis.

BACKGROUND: The risk factors for radiation pneumonitis (RP) in patients with chronic obstructive pulmonary disease (COPD) are unclear. Mean lung dose (MLD) and percentage of irradiated lung volume are common predictors of RP, but the most accurate dosimetric parameter has not been established. We hypothesized that the total lung volume irradiated without emphysema would influence the onset of RP. METHODS: We retrospectively evaluated 100 patients who received radiotherapy for lung cancer. RP was graded according to the Common Terminology Criteria for Adverse Events (version 4.03). We quantified low attenuation volume (LAV) using quantitative computed tomography analysis. The association between RP and traditional dosimetric parameters including MLD, volume of the lung receiving a dose of ≥2 Gy, ≥ 5 Gy, ≥ 10 Gy, ≥ 20 Gy, and ≥30 Gy, and counterpart measurements of the lung without LAV, were analyzed by logistic regression. We compared each dosimetric parameter for RP using multiple predictive performance measures including area under the receiver operating characteristic curve (AUC) and integrated discrimination improvement (IDI). RESULTS: Of 100 patients, RP of Grades 1, 2, 3, 4, and 5 was diagnosed in 24, 12, 13, 1, and 1 patients, respectively. Compared with traditional dosimetric parameters, counterpart measurements without LAV improved risk prediction of symptomatic RP. The ratio of the lung without LAV receiving ≥30 Gy to the total lung volume without LAV most accurately predicted symptomatic RP (AUC, 0.894; IDI, 0.064). CONCLUSION: Irradiated lung volume without LAV predicted RP more accurately than traditional dosimetric parameters.

Involvement of Ca2+ Signaling in the Synergistic Effects between Muscarinic Receptor Antagonists and ß2-Adrenoceptor Agonists in Airway Smooth Muscle.

Long-acting muscarinic antagonists (LAMAs) and short-acting ß2-adrenoceptor agonists (SABAs) play important roles in remedy for COPD. To propel a translational research for development of bronchodilator therapy, synergistic effects between SABAs with LAMAs were examined focused on Ca2+ signaling using simultaneous records of isometric tension and F340/F380 in fura-2-loaded tracheal smooth muscle. Glycopyrronium (3 nM), a LAMA, modestly reduced methacholine (1 µM)-induced contraction. When procaterol, salbutamol and SABAs were applied in the presence of glycopyrronium, relaxant effects of these SABAs are markedly enhanced, and percent inhibition of tension was much greater than the sum of those for each agent and those expected from the BI theory. In contrast, percent inhibition of F340/F380 was not greater than those values. Bisindolylmaleimide, an inhibitor of protein kinase C (PKC), significantly increased the relaxant effect of LAMA without reducing F340/F380. Iberiotoxin, an inhibitor of large-conductance Ca2+-activated K⁺ (KCa) channels, significantly suppressed the effects of these combined agents with reducing F340/F380. In conclusion, combination of SABAs with LAMAs synergistically enhances inhibition of muscarinic contraction via decreasing both Ca2+ sensitization mediated by PKC and Ca2+ dynamics mediated by KCa channels. PKC and KCa channels may be molecular targets for cross talk between ß2-adrenoceptors and muscarinic receptors.

A case of pulmonary cholesterol granuloma: an (18)F-fluorodeoxyglucose positron emission tomography image.

A 77-year-old woman with Sjögren's syndrome has been followed for mild interstitial pneumonia. A 2-cm pulmonary nodule was incidentally found in the left lower lobe, and positron emission tomography-computed tomography showed (18)F-fluorodeoxyglucose uptake with a maximum standardized uptake value of 8.78 in this nodule. Although this suggested a malignant disease, transbronchial biopsy of the nodule revealed that it was cholesterol granuloma. It is known that some benign inflammatory diseases show an increased uptake of (18)F-fluorodeoxyglucose, particularly granulomatous lesions like tuberculosis. To our knowledge, this is the first report of (18)F-fluorodeoxyglucose-positron emission tomography findings for cholesterol granuloma. We speculate that increased (18)F-fluorodeoxyglucose uptake with cholesterol granuloma occurs through cellular infiltration and macrophage proliferation, resulting in the activation of glycolysis-like tuberculosis.

Diagnosis of pulmonary mucormycosis aiding the diagnosis of small cell lung cancer.

Mucormycosis is a rare complication in immunocompromised patients. Antemortem diagnosis of mucormycosis is difficult and often incorrect. We report a case of pulmonary mucormycosis caused by Cunninghamella bertholletiae in an elderly man with interstitial pneumonia. The diagnosis of mucormycosis was established by bronchoalveolar lavage. A coexisting immune deficiency condition was considered. Lung cancer was suspected because of an elevated progastrin-releasing peptide level and bilateral hilar and mediastinal lymphadenopathy; it was diagnosed after performing endoscopic ultrasound-guided fine-needle aspiration. Treatment by intravenous liposomal amphotericin B was effective, but relapse occurred because of bone marrow suppression caused by chemotherapy for lung cancer. Treatment for mucormycosis was resumed, but the patient died of carcinomatous lymphangiosis. Autopsy confirmed the diagnosis of pulmonary mucormycosis and revealed refractory anaemia with small cell lung cancer. Mucormycosis often occurs in immunocompromised patients, but this case is rare because the mucormycosis was diagnosed before the diagnosis of malignancy. Because prognosis is often poor, the possibility of coexisting malignancies should always be investigated in patients with mucormycosis infections.