Analysis Of CT Signs Of Peripheral Small Cell Lung Cancer

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Analysis of CT signs of peripheral small cell lung cancer?Objective?To investigate CT signs of peripheral small cell lung cancer(SCLC).?Materials and Methods?We retrospectively reviewed the CT signs of SCLC of 78 patients confirmed by pathology.According to the presence of mediastinal lymph node metastasis and its size,78 cases of peripheral SCLC is divided into two types: type?(isolated lesion)and type?(lung lesion + lymph nodes),and type? can be divided into two subtypes:type?a(short diameter of lymph nodes of pulmonary hilar and mediastinum less than 10 mm)and type?b(short diameter of lymph nodes of pulmonary hilar and mediastinum greater than or equal to 10 mm).?Results?Of the 78 SCLCs,type? was 7 cases,and type? was 71 cases.including 8 cases of type?a and 63 cases of type?b.All of the lesions were soild density.The shape were round or oval in 52 cases,vermicular or spindle shape in 9 cases,and other shapes in 17 case.Among 71 cases performed CT enhancement,there were 9 cases with homogeneous enhancement,58 cases with heterogeneous enhancement,4 cases with non-enhancement large necrosis area.These cases shows the following CT signs:smooth edge in 65 cases,coarse edge in 12 cases,blurred edge in 1 cases;air bronchogram in 3 cases,vacuole sign in 4 cases,calcification in 4 cases;lobulation sign in 46 cases,spiculated sign in 5 cases;thickening of the bronchovascular bundle in 41 cases,pleural indentation in 6 cases,marginal ground-glass opacity in 5 cases,vascular convergence sign in 1 case,emphysema in 42 cases,obstructive pneumonia in 4 cases.bronchus abruptly obstructed on the edge of the nodules in 18 cases.enlargement of mediastinal lymph nodes in 63 cases,the diameter of mediastinal lymph nodes larger than the primary lesions in 42 cases;and a little pleural effusion 9cases.?Conclusion?Solid density,smooth margin with obulation,and significantly enlarged mediastinal lymph nodes are common signs in peripheral SCLC.Thickening of the bronchovascular bundle indicates reletively advanced patients.Part ? Diagnostic value of string beads sign in peripheral small cell lung cancer?Objective?To investigate the formation mechanism of string beads sign in peripheral small cell lung cancer(SCLC)and evaluate the significance of it in differential diagnosis among SCLC,peripheral lung adenocarcinoma and peripheral lung squamous cell carcinoma.?Materials and Methods?78 cases of SCLC,69 cases of peripheral lung adenocarcinoma and 33 cases of peripheral lung squamous cell carcinoma,confirmed pathologically,were included in this study.The positive rates of string beads sign,mediastinal lymph node metastasis and mediastinal lymph nodes larger than primary lung lesions were calculated and analyzed in these three groups.?Results?10 out of SCLC cases(12.8%)have string beads sign,in which all mediastinal lymph nodes were larger than lung lesions.Mediastinal lymph node metastases were observed in 63(80.8%)of 78 cases,and 42(53.8%)cases had larger mediastinal lymph nodes than lung lesions.No string beads sign was observed in patients with peripheral solid lung adenocarcinomas,but 25 of 69 cases(36.2%)have mediastinal lymph node metastasis and 2 cases(2.9%)had larger mediastinal lymph nodes than lung lesions.13 cases(39.4%)of 33 patients with peripheral lung squamous cell carcinomas had mediastinal lymph node metastasis,and 6 cases(16.7%)had larger mediastinal lymph nodes than lung lesions.The statistical results showed the positive rate of string beads sign was not significantly different between peripheral SCLC group and peripheral lung squamous cell carcinoma group,but that of mediastinal lymph node and larger mediastinal lymph nodes than lung lesions were statistically different among these three groups.?Conclusion?To some extent,string beads sign on CT could reflect the biologic character of SCLC.It played an important role in differential diagnosis of peripheral SCLC,peripheral lung adenocarcinoma and peripheral lung squamous cell carcinoma,but itshould be combined with mediastinal lymph node size.Part ? CT findings of abnormal bronchovascular bundle in peripheral small cell lung cancer?Objective?To investigate CT findings of abnormal bronchovascular bundle in patients with peripheral small cell lung cancer(SCLC).?Materials and Methods?We retrospectively reviewed the CT findings of abnormal bronchovascular bundle in 78 peripheral SCLC patients confirmed by pathology.Abnormal bronchovascular bundle of peripheral SCLC was divided into three types:type?(thickening of the bronchovascular bundle),type?(string beads of bronchovascular bundle)and type?(bronchial cast with bronchus cut-off).?Results?41(52.6%)of 78 patients had abnormal bronchovascular bundle,in which 26 cases was type?,10 for type?,5 for type?.Except for 1 case with no mediastinal lymph node metastasis among 41 cases with abnormal bronchovascular bundle,all other 40 cases had mediastinal lymph node metastasis.?Conclusion?To some extent,abnormal bronchovascular bundle could reflect the biologic character of SCLC.Abnormal bronchovascular bundle was associated wih advanced patients.