Diagnostic Value Of DWI In The Lung Mass With Different Pathological Types Of Lung Cancer

Objective: To investigate the diagnostic value of diffusion-weighted imaging(DWI) in the benign and malignant lung masses, discussing the signal of DWI、ADC values and the correlation of lung neoplasm differentiation degree.Materials and Methods: This retrospective study was approved by the hospital ethics committee. The research object of March 2009 to August 2014 menstrual CT found pulmonary lumps, parallel MRI plain scan(T1WI、T2WI)and DWI examination can.We collected the standard of 75 patients, 81 cases of tumors, 38 Male(mean age:62.0±5.6years), 37 women(mean age: 60.2±3.4years).Among them,43 cases were malignant tumors, 30 cases were confirmed by surgery and 13 cases by biopsy, the lumps range is 1.5-12.5 cm in diameter, and the average diameter of 3.14 cm, The final pathological diagnosis was jointly by two pathologists Benign lumps are 38 cases, 7 cases were confirmed by surgery pathology and follow-up found lesions decreased in 16 cases, 14 cases were clinical tests verify, punctured proof in 1 case, with benign mass range of 1.0-6.7 cm in diameter, the average diameter of 3.0 cm.All cases underwent the dele plain MRI(T1WI、T2WI) and DWI sequence, b-value was choiced 500s/mm2. We analyzed the lesion size, DWI signal and calculated ADC value, avoiding artifacts、blood vessels、bronchi、hemorrhage and necrosis area.Statistical analysis was performed with SPSS(17.0 edition).Intraclass correlation coefficient(ICC) was used to test the consistency of the different ADC values. ADC values of benign and malignant tumors did normal distribution analysis, all accord with normal distribution, and then used the group t-test for benign and malignant lung tumor, and different pathological types of ADC values did statistical analysis. We applied one-way ANOVA test to compare ADC values of the groups. Area under the ROC curve was used to evaluate the ADC values and their diagnostic ability and threshold value of different types of benign and malignant lung tumor, the curve of three groups were analysed by chi-square test. Diagnostic sensitivity and specificity of TIC for the three kinds of diseases were analyzed by ROC. Associations were considered statistically significant when P≤0.05.ResultsThe two measured ADC values consistent results as follows: individual measurement is 0.899, the average measurement is 0.947. Most malignant tumor DWI signal is high, slightly lower or mixed signal(34/43); Benign lumps DWI signal is low, mostly can give priority to with slightly lower, low signal(26/38); Lung mass average ADC values is different, the benign lumps average ADC values is(1.851±0.647) x10-3mm2/s, malignant tumor average ADC values is(1.428±0.340)x10-3mm2/s, two independent sample t test results show that ADC values differences of the benign and malignant tumors is statistically significant(p < 0.05); Benign and malignant tumor area under the ROC curve is 0.72, diagnostic significance.Conclusions1. DWI imaging and ADC values have diagnostic value for differentiating benign and malignant lung masses;2. The ADC values have certain significance in lung adenocarcinoma with differentiation.