| Purpose To report result of low-dose computed tomography (LDCT) screening for early-stage lung cancer of 4690 asymptomatic participants in China.Methods After informed written consent was obtained,4690 asymptomatic volunteers (3302 in men, age range 40-85, mean age 47.0; 1388 in women, age range 40-88, mean age 49.0) who underwent spiral chest LDCT were enrolled. LDCT scanning protocol, criterion of further work-up according to the size and consistency of pulmonary nodules were compliant with International Early Lung Cancer Active Program (I-ELCAP). TNM staging of all lung cancers were based on the clinical evidence and pathological findings.Results Initial LDCT scanning led to recommendations for further work-up in participants of various risk status for lung cancer based on National Comprehensive Cancer Network (NCCN, version 2.2014) were 27.0%(86/319) in high-risk individuals,19.3% (199/1029) in moderate-risk individuals,11.3%(377/3342) in low-risk individuals. Twenty-seven (11 in men, age range 42-71, mean age 49.0; 15 in women, age range 38-75, mean age 58.0) lung cancers were diagnosed in 26 participants (0.6%,26/4690), among them 24 non-small cell tumors were proved by pathology, of which 19 were early tumors (76.0%,19/24). Diameter of cancers detected was 6.9-29.5 mm (median,16.3 mm). Detection of primary pulmonary tumor in individuals of various risk status did not show statistical significance (P=0.054). For female individuals who aged 40 or older with the history of being exposed to second-hand smoke, the proportion of lung cancers in the LDCT positive nodules showed significant difference compared to the high-risk individuals (7.19% vs.2.94%, P=0.002)Conclusion The results indicate that LDCT can detect small lung cancers and most of the cancers are detected at an early stage. Emphasis should be placed on the female individuals who aged 40 or older with the history of being exposed to second-hand smoke in China.Purpose:To determine the association of pulmonary nodule detection on the baseline low-dose CT screening with age and smoking status of the asymptomatic participants.Materials and Methods:3,363 participants who 40 years or older were enrolled in the lung cancer screening program between July 2008 and June 2012. The age and smoking history were included in the questionnaires. Participants were deviede into 5 subgroups by age:40-49 (n= 1723,51.2%),50-59(n= 1061,31.5%),60-69 (n=442,13.1%),70-79 (n= 125,3.7%) and 80-89 (n=12,0.4%). Status of smoking of each individual was reviewed and classified into 4 categories:never smoking (n=1695,50.4%), light smoking (smoking index, SI<20) (n= 690,20.5%), heavy smoking (SI≥20 to 30) (n=430,12.8%), and extreme-heavy smoking (SI≥30) (n=548,16.3%). The nodule detection rate, positive results rate and size of the nodule by age and status of smoking of participants were compared. The correlation between the quantity and size of the nodule and the various groups were calculated.Results:2,295 (68.2%) of 3,363 participants had at least one non-calcified nodule in baseline. Detection rate for each subgroup of age was 64.1%(40-49),71.4%(50-59),74.7% (60-69),76.0%(70-79), and 66.7%(80-89), respectively. Lung nodules were more frequently identified in the participants aged 50-79 than 40-49 and 80-89 (P<0.001). Detection rate of each category of smoking status was 67.7%(non-smoker),68.7%(light smoker),65.8%(heavy smoker) and 71.4%(extreme-heavy smoker), respectively. Lung nodules are more likely identified in the participant with extreme-heavy smoking, however, the difference was not significant (P=0.269). The number and size of nodule identified was significantly correlated with the increasing age (0.110/0.111) and smoking index (0.115/0.048) of participants.556 (16.5%) participants had at least one positive nodule. Detection rate of positive nodule was significantly increased with increasing age between 40 and 79; it was 11.9% in 40-49,17.9% in 50-59,25.1% in 60-69,37.6% in 70-79 (P< 0.001). Detection rate of positive nodule was 16.1% in non-smoker,14.3% in light smoker, 13.7% in heavy smoker,22.8% in extreme-heavy smoker. Positive nodule was identified with significant higher frequency in the participants in the status of extra-heavy smoking (P<0.001).25 participants with malignant nodules were identified. Detection rate of malignant nodules of the various age group was 0.5%,0.7%,0.9% and 4.0%, respectively. Detction rate of malignant nodules of different smoking status groups was 1.0%,0.1%, 0.7% and 0.7%. Significant correlation was found between the number and size of positive nodule detected and increasing age (0.098/0.1240) as well as smoking index (0.124/0.057) of participantsConclusion:Detection rate of lung nodules and the age have positive correlation. The detection rate of lung nodules have no association with the smoking status or smoking index of participants on the baseline low-dose CT of lung cancer screening. |
PDF Full Text Request