RESUMO
INTRODUCTION: An increase in detection of early-stage asymptomatic lung tumors could increase the overall survival rate of lung cancer patients. A new approach to cancer (pre-)screening focusses on detecting field cancerization instead of the tumor itself. The objective of this study was to investigate the use of optical spectroscopy to detect field cancerization in the buccal mucosa of lung cancer patients. METHODS: Optical buccal mucosa measurements were performed in lung cancer patients and controls using multidiameter single-fiber reflectance spectroscopy. We analyzed whether the measured optical parameters could distinguish lung cancer patients from controls. RESULTS: Twenty-three lung cancer patients, 24 chronic obstructive pulmonary disease (COPD) control patients, and 36 non-COPD controls were included. The majority of tumors were non-small-cell lung carcinomas (96%) and classified as stage I (48%). The tissue scattering properties µs' and γ at 800 nm and the tissue bilirubin concentration were all near-significantly different (P=.072, 0.058, and 0.060, respectively) between the lung cancer and COPD group. µs' at 800 nm had a sensitivity of 74% and a specificity of 63%. The microvascular blood oxygen saturation of the lung cancer patients was also higher than the COPD patients (78% vs. 62%, P=.002), this is probably a consequence of the systemic effect of COPD. CONCLUSIONS: We have demonstrated that µs' at 800 nm is increased in the buccal mucosa of patients with lung cancer compared to controls with COPD. This might be an indication of field cancerization in the oral cavity of patients with lung cancer.
RESUMO
Ghrelin is a hormone produced by endocrine cells in the stomach. Ghrelin stimulates the secretion of growth hormone by the anterior pituitary. This effect is mediated by hypothalamic growth-hormone secretagogue receptors. Binding to these receptors not only stimulates growth hormone secretion, but also has vascular effects (positive inotropic effects), modifies (decreases) insulin sensitivity, affects glucose metabolism (hyperglycaemia) and stimulates gastric-acid production. Antiproliferative effects of ghrelin have been described on experimental tumour models. Ghrelin seems to play a role in stimulating the appetite as well as promoting a more effective storage of food components. Whether or not ghrelin could play any role in the induction of weight gain has yet to be established. This is also true for the role of potential ghrelin antagonists in the induction of weight loss in case of obesity.