MSCT Findings And Pathologic Correlation Study Of Lung Large Cell Neuroendocrine Carcinoma

Objective:To study the imaging findings and pathologic correlation of lung large cell neuroendocrin carcinoma(LCNEC),to facilitate the diagnosis of LCNEC.Methods:MSCT and pathologic findings of27patients of LCNEC were reviewed. All patients received plain CT scan and20of them received enhanced CT scan. All patients received pathological and immunohistochemical examination after postoperation.Results:In the27patients,all patients were presented as a mass in the lung. The diameters of27patients ranged from1.2to14.2cm ([5.2±2.1] cm). The main features in the tumor were located peripherally in26cases, located centrally in1case; located upper lobe of left lung in6cases (6/27,22.22%), located inferior lobe of left lung in4cases (4/27,14.81%),located upper lobe of right lung in8cases (8/27,29.63%), located middle lobe of right lung in3cases (3/27,11.11%),located inferior lobe of right lung in6cases (6/27,22.22%); nearly-circular in2cases, lobulation in19cases (19/27,70.37%), irregular shape in4cases; spiculation in7cases (7/27,25.93%) smooth and well defined in20cases (20/27,74.07%); mass density uniform in16cases (16/27,59.26%),necrosis in9cases (9/27,33.33%) which have3cases of hollow or cavity, calcification in2cases (2/27,7.41%), pleural traction7in cases (7/27,25.93%), obstructive atelectasis or pneumonia in4cases (4/27,14.81%). Fourteen cases (14/27,51.85%) were with lymph nodes tumefaction in which8cases had metastasized. All20patients of masses density were well-distributed after contrast-enhanced CT. Put the net added value of CT value is divided into three levels:20or less HU for mild of intensive,20-40HU for moderate of intensive, or40HU for severe reinforcement. The fifteen of the20patients with non-uniform strengthen,4cases for mild reinforcement,13cases for moderate strengthening,10cases for severe reinforcement. In27patients with LCNEC, neurone specific enolase(NSE) was positive for16cases (16/27,59.26%), chromogranin A(CgA) was positive in2cases (2/27,7.41%), synaptophysin (Syn) was positive for17cases (17/27,62.96%),8cases of neural cell adhesion molecule CD56was positie, In27patients with10cases of tubulin have tested positive for;12 cases of vascular endothelial growth factor (VEGF) have tested positive for;2cases of thyroid transcription factor1(TTF-1), in which1case was positive,1case of cell keratin7(cytokeratin, CK7), testing positive.Conclusion:LCNEC is lack of characteristic clinical manifestations. Occurs in older men, most of the patients with a history of smoking. Imaging performance for the lungs more single peripheral lump, the edge finishing, leaves with more point, which has necrosis, calcification、 hollow or cavity and contains air bronchogram, rare lesion is more uneven enhancement. Simple imaging can not diagnose LCNEC, should be combined with pathology analysis together. Pathologically to satisfy both morphology and differentiation characteristics of neuroendocrine tumors, At least one kind of neuroendocrine markers for immunohistochemical staining was positive, including the NSE, CgA, Syn and CD56.