原发性肺淋巴上皮瘤样癌的CT及PET/CT表现与病理对照

Primary Pulmonary Lymphoepithelioma-Like Carcinoma: The CT and PET/CT-Pathologic Correlation

目的探讨原发性肺淋巴上皮瘤样癌(LELC)的CT和PET/CT表现及其病理特点。方法回顾性分析经手术或穿刺活检病理证实的127例原发性肺LELC患者的临床、影像及病理资料。127例患者均行胸部CT平扫,其中117例行CT增强扫描;38例行PET/CT检查。观察其影像学表现并与病理进行对照。结果 127例LELC中,中央型45例(45/127,35%),周围型82例(82/127,65%)。病灶最大径1.0～12.3 cm,平均(5.00±2.41)cm。结节或团块型118例,其中单发112例,多发6例;叶或段实变型9例。99例(99/127,78%)边界清晰,100例(100/127,79%)边缘分叶,毛刺征49例(49/127,39%)。88例(88/127,69%)平扫密度均匀,空洞17例(17/127,13%)、钙化14例(14/127,11%)、坏死8例(8/127,6%)。增强后病灶多呈渐进性强化,57例(57/96,59%)动脉期瘤内可见血管影。89例(89/127,70%)可见气管或支气管受累、包埋,74例(74/127,58%)合并阻塞性炎症/肺不张。89例(89/127,70%)合并肺门及/或纵隔淋巴结肿大。38例PET/CT检查病灶内标准摄取值(SUV)最大值范围为2.1～28.5,平均13.00±6.65。镜下病理分型Regaud型82例,Schmincke型35例,所有病例EBER均阳性。结论原发性肺LELC多表现为密度均匀、边界清晰、边缘分叶的结节或团块,呈渐进性强化,动脉期多可见瘤内新生血管影,支气管多受累、包埋,氟代脱氧葡萄糖(^(18)F-FDG)呈明显高摄取。

Objective To investigate the CT,PET/CT and pathologic features of the primary pulmonary Lymphoepithelioma-like Carcinoma(LELC). Methods The clinical,imaging and pathological data of 127 patients with LELC,who were proved by surgery or biopsy pathology,were retrospectively analyzed.117 patients underwent contrast enhanced CT scan,only 10 patients underwent CT scan without contrast injection,38 patients also underwent PET/CT scan.Imaging findings were analyzed and correlated with pathologic features.All cases were proved primary pulmonary LELC with exclusion of the cases of nasopharyngeal lymphoepithelioma-like carcinoma. Results 45 central tumors(45/127,35%)and 82 peripheral tumors(82/127,65%)were identified based on the location of the tumor.The maximum diameter of the tumor ranged from 1.0 to 12.3 cm(mean 5.00±2.41 cm).The tumor displayed as solitary nodule or mass in 112 cases,as multiple nodules in 6 cases,as lobar or segmental consolidation in 9 cases.The tumor displayed well-defined margin in 99 cases(99/127,78%),lobular sign in 100 cases(100/127,79%),spicule sign in 49 cases(49/127,39%),cavitation in 17 cases(17/127,13%),calcification in 14 cases(14/127,11%),and necrosis in 8 cases(8/127,6%).88 cases showed homogeneous density in non-enhanced CT(88/127,69%).Most of the tumors demonstrated gradual enhancement,while small vessels inside the tumor were found in 57 cases(57/96,59%).The encasement of trachea or bronchus was found in 89 cases(89/127,70%).Obstructive inflammation or atelectasis was found in 74 cases(74/127,58%).Hilar and/or mediastinal lymphadenopathy was seen in 89 patients(89/127,70%).38 cases with PET/CT scan demonstrated avid FDG uptake with SUV ranged from 2.1 to 28.5(mean 13.00±6.65). The pathologic classification included 82 cases of Regaud type and 35 cases of Schmincke type.EBER was positive in all cases. Conclusion The primary pulmonary LELC demonstrate well-defined margin,lobulated sign,homogeneous density in non-enhanced CT,gradual enhancement and small vessels inside the tumor.