Incidence and mortality of thyroid cancer in China, 2008-2012

Objective: To analyze the incidence and mortality rates of thyroid cancer(TC) in China from 2008 to 2012.Methods: Incident and death cases of TC were retrieved from the National Central Cancer Registry(NCCR)database collecting from 135 cancer registries in China during 2008-2012. The crude incidence and mortality rates of TC were calculated by area(urban/rural), region(eastern, middle, western), gender and age group(0, 1-4, 5-9,…, 85+). China census in 2000 and world Segi's population were applied for age-standardized rates. Joinpoint(Version 4.6.0.0) model was used for time-trend analysis.Results: The crude incidence rate of TC was 7.56/100,000 which ranked the seventh in overall cancers. The agestandardized incidence rates by China population(ASIRC) and by World population(ASIRW) were 6.25/100,000 and 5.52/100,000, respectively. The crude mortality of TC in China was 0.52/100,000. The age-standardized mortality rates by Chinese standard population(ASMRC) and by world standard population(ASMRW) were0.34/100,000 and 0.32/100,000, respectively. Incidence and mortality rates of TC were higher in females than in males and higher in urban areas than in rural areas. Eastern areas had the highest incidence followed by middle and western areas. TC incidence increased dramatically after age of 15 years, then peaked at 14.08/100,000 in the group of 50-54 years and finally decreased sharply after 55 years old. TC mortality increased with age in population,reaching the peak of 5.09/100,000 in sub-population aged 85 years or older. TC incidence increased by 4.73 times from 2.40/100,000 in 2003 to 13.75/100,000 in 2012 with an average annual increase of 20%, while TC mortality only increased slightly around 0.32/100,000 from 0.26/100,000 to 0.36/100,000.Conclusions: Appropriate targeted prevention, early detection and treatment programs can be carried out to curb the rapid growth trend of TC and control the disease burden.

Elemental analysis of copper alloy by high repetition rate LA-SIBS using compact fiber spectrometer

High repetition rate laser-ablation spark-induced breakdown spectroscopy(HRR LA-SIBS) was first used to analyze trace elements in copper alloy samples. The 1064 nm output of an acoustooptically Q-switched Nd:YAG laser operated at a pulse repetition rate of 1 kHz was utilized to ablate copper alloy and to form original plasma, spark-discharge was applied to further breakdown the ablated samples and enhance the emission of the laser-induced plasma. A compact multichannel fiber spectrometer was used to analyze the plasma emission under nongated operation mode. Under the assistance of high repetition rate spark discharge, the plasma emission was able to be improved significantly. The determined limits of the detection of lead and aluminum were 15.5 ppm and 1.9 ppm by HRR LA-SIBS, respectively, which were 11 and 6 folds better than that determined by HRR LIBS under the same laser-ablation condition. This work demonstrates the feasibility of using fiber spectrometer to analyze plasma emission under non-gated operation mode and the possibility of building a portable HRR LA-SIBS system for rapid elemental analysis of copper alloys and other solid samples.