Analysis Of Correlation Between Clinical Pathology And Pulmonary Nodules Diagnosed By PET/CT In 103 Cases

Objective:With the popularization of chest CT examination and the increasing concern of the whole people for health check-up,the discovery of pulmonary nodules and the demand for qualitative characterization of pulmonary nodules has increased.PET/CT has attracted much attention because of its ability to detect nodules,and it can judge the benign and malignant pulmonary nodules by the difference of nodule uptake rate of fluorodeoxyglucose.In this study,103 cases of pulmonary nodules diagnosed by PET/CT were studied by pathological comparison after operation.Methods:A retrospective analysis of 103 patients with pulmonary nodules diagnosed by PET/CT in our hospital was conducted from January 2015 to January 2017.103 patients with suspected malignant nodules were quickly removed from the nodules during surgery,and routine HE staining was performed rapidly.The remaining specimens were routinely taken,and were immunohistochemical staining and histochemical staining as necessary to ensure the accuracy of the diagnostic results of the paraffin sections.Postoperative pathological analysis,the maximum standardized uptake of PET(SUVmax)and CT morphological characteristics were used to evaluate the nature of nodules.All data were processed by software SPSS17.0.The count data was expressed by frequency or percentage.The comparison between groups was performed by χ2 test.The measurement data were expressed by mean ± standard deviation.The comparison between groups was performed by t test,analysis of variance and rank sum test.Correlation factors were analyzed using Pearson correlation analysis.It was considered statistically significant by P < 0.05.RESULTS: Among the 103 patients with suspected malignant nodules by postoperative pathology,81 patients were confirmed to be malignant nodules;and 22 patients were confirmed to benign nodules.The pathological distribution of 81 patients with malignant nodules was 66 cases of adenocarcinoma(64 cases were primary lung cancer,2 cases were metastatic carcinoma),9 cases of squamous cell carcinoma,2 cases of adenosquamous carcinoma,1 case of small cell lung cancer,1 case of large cell lung cancer,1 case of sarcomatoid carcinoma,1 case of poorly differentiated carcinoma.There were 73 nodules in 66 patients with adenocarcinoma.There were 3 situ carcinomas(TIS),6 microinvasive carcinoma s(MIA),and 64 invasive carcinomas by the paraffin pathology.The mean age of patients with malignant nodules in this study was significantly higher than that of benign nodules,[(61.05±9.83)years vs.(55.64±9.86)years],the difference was statistically significant(P<0.05);the lesions sizes of malignant nodules were higher than the sizes of benign nodules,[(1.95±0.69)cm vs(1.38±0.75)cm],the difference was statistically significant(P<0.05).There were significant differences between malignant nodules and benign nodules in SUVmax,and the difference was statistically significance(8.48±4.98 vs 3.85±3.87,P<0.05).Pathological findings suggest that malignant nodules are positively correlated with their size of SUVmax(r = 0.467,P < 0.05).The diagnosis of lung cancer by PET/CT in 72 patients was consistent with the postoperative pathological results.The increase of the diameter of pulmonary nodules,the proportion of pleural indentation,vascular insertion,lobulation and burr sign increased,the differences were statistically significant(P <0.05).The diameter of nodules increased,the SUVmax of PET/CT was increased significantly,and the difference was statistically significant(P <0.05).The larger the diameter of the nodules,the lower the proportion of GGO,the higher the solid ratio of nodules,the higher the SUVmax of PET/CT,it was the more obvious by the CT signs of CT,the difference was statistically significant(P <0.05).The SUVmax of squamous cell carcinoma was significantly higher than that of adenocarcinoma(12.8±2.9 vs 7.7±4.9),and the difference was statistically significant(P <0.05).There were 4 cases of TIS,9 cases of T1 a,43 cases of T1 b,25 cases of T1 c in this study.There were significant differences in SUVmax between different T stages,and the difference was statistically significant(4.3±3.8 vs 4.7±3.9 vs 5.8 ±4.0 vs 8.0±5.1 vs 11.2±4.3,P <0.05).PET/CT has a false negative and false positives for the diagnosis of lung cancer,especially the false negative rate reach to 9% in this studycancer.focus on the false negative problem.Conclusion: PET / CT has important clinical value in the early diagnosis of pulmonary nodules,but it still is verified by pathology.It is based on insufficient evidence evidently for the identification of malignant nodules by SUVmax,it still need to require comprehensive analysis of CT signs and clinical features of the nodules.In particular,histopathological diagnosis is still the gold standard for the diagnosis of lung cancer.As a non-invasive and safe examination method,It is an important imaging basis for the diagnosis of benign and malignant pulmonary nodules。 However,it is necessary to pay attention to the fact that PET/CT still has certain false positives and false negatives in the diagnosis of malignant pulmonary nodules,especially the false negative problem.