Risk-adapted stereotactic body radiation therapy for central and ultra-central early-stage inoperable non-small cell lung cancer.

To determine the therapeutic efficacy and safety of risk-adapted stereotactic body radiation therapy (SBRT) schedules for patients with early-stage central and ultra-central inoperable non-small cell lung cancer. From 2006 to 2015, 80 inoperable T1-2N0M0 NSCLC patients were treated with two median dose levels: 60 Gy in six fractions (range, 48-60 Gy in 4-8 fractions) prescribed to the 74% isodose line (range, 58%-79%) for central lesions (ie within 2 cm of, but not abutting, the proximal bronchial tree; n = 43), and 56 Gy in seven fractions (range, 48-60 Gy in 5-10 fractions) prescribed to the 74% isodose line (range, 60%-80%) for ultra-central lesions (ie abutting the proximal bronchial tree; n = 37) on consecutive days. Primary endpoint was overall survival (OS); secondary endpoints included progression-free survival (PFS), tumor local control rate (LC), and toxicity. Median OS and PFS were 64.47 and 32.10 months (respectively) for ultra-central patients, and not reached for central patients. Median time to local failure, regional failure, and any distant failures for central versus ultra-central lesions were: 27.37 versus 26.07 months, 20.90 versus 12.53 months, and 20.85 versus 15.53 months, respectively, all P < .05. Multivariate analyses showed that tumor categorization (ultra-central) and planning target volume ≥52.76 mL were poor prognostic factors of OS, PFS, and LC, respectively (all P < .05). There was one grade 5 toxicity; all other toxicities were grade 1-2. Our results showed that ultra-central tumors have a poor OS, PFS, and LC compared with central patients because of the use of risk-adapted SBRT schedules that allow for equal and favorable toxicity profiles.

[Study on the Effect of Sodium Chloride Salt on Near-Infrared Spectroscopy of Glucose Aqueous Solution].

The sodium chloride (NaCl) salt has been reported to be associated with glucose metabolism. However, the effect of it on non-invasive detection of blood glucose using near-infrared spectroscopy is still an open question. The aim of this study was to investigate this affection through transform background correction analysis two-dimensional (2D) correlation synchronous spectrum and the partial least-squares (PLS) regression. First, the transmittances of glucose aqueous solutions with different NaCl content are collected and the pure water and NaCl aqueous solution are measured as the background. Results show that, the dissolving of NaCl in water changes the amplitude and position of the absorption peak of water. There are two negative peaks in 1 400 and 1 500~1 700 nm corrected spectra of NaCl aqueous obviously and the amplitude of peaks associated with NaCl concentration. That's because NaCl affect the molecular binding and vibration of water. Then the glucose aqueous solutions without NaCl and with NaCl are corrected by the spectra of pure water and NaCl aqueous solution, respectively. So we get the conclusion that NaCl also affect the combination of glucose and water molecules. And the two-dimensional correlation spectroscopy analysis is performed under the perturbation of glucose concentration. The slice spectra of synchronous correlation spectra show that, the adding of NaCl weakens the spectral variation due to glucose concentration change in the wavelength of 1 400 and 1 520~1 700 nm. Finally, the partial least square (PLS) regression models were built to quantitatively conduct the influence of NaCl on glucose prediction accuracy. Comparison results showed that, NaCl molecule in aqueous solution will deteriorate the model accuracy, where root mean square error of prediction increases with the NaCl content; the mean difference of predicted glucose concentration between models based on glucose aqueous solutions with NaCl and without NaCl, is linear with NaCl concentration in samples.

An improved algorithm of temperature compensation for a near infrared multiple-acquisition system based on two-dimensional regression analysis.

The near infrared (NIR) spectroscopy analytical technique is one of the most advanced and promising tools in many domains. NIR acquisition is easily influenced by temperature, thereby affecting qualitative and quantitative analyses. In this paper, a temperature compensation model was established between NIR signals and output voltage values based on two-dimensional regression analysis. The effectiveness of the proposed compensation scheme was experimentally demonstrated by the measurement of six super luminescent diode sources at 293-313 K. The coefficient of variation was decreased 2-fold with this compensation algorithm. The results indicated that it was suitable for various NIR spectral acquisition systems with lower complexity and a higher signal-noise-ratio after being applied to an acousto-optic-tunable-filter system.