肺类癌致异位促肾上腺皮质激素综合征的影像学特点分析

Imaging characteristics analysis on ectopic adrenocorticotropic hormone syndrome caused by nodular bronchial carcinoid

目的:探讨影像手段在隐匿性小结节型样肺类癌致异位促肾上腺皮质激素综合征(EAS)中的诊断价值。方法:回顾性分析我院收治并确诊的两例小结节样肺类癌致EAS患者的影像资料,包括:MRI、PET-CT、胸部CT、双侧岩下窦静脉采血、肺结节穿刺活检术;结合患者临床表现和实验室检查,通过文献分析总结此类病例的影像特点。结果:两例患者均有明显的库欣综合征表现,外周血促肾上腺皮质激素(ACTH)明显升高,皮质醇分泌无昼夜节律。MRI资料提示不能排除垂体微腺瘤,双侧岩下窦静脉采血排除了垂体来源ACTH瘤,因胸部CT均发现类圆形小结节,一例右上肺结节穿刺活检证实肺类癌来源ACTH瘤;另一例左下肺结节选择直接胸腔镜手术切除。手术切除后行病理学检查示一例为低分化类癌,另一例为不典型类癌。结论:支气管肺部类癌是导致EAS的常见病因之一,如青壮年库欣综合征患者同时发现肺部小结节,MRI或双侧岩下窦静脉取血排除了垂体来源的ACTH瘤,应警惕排除肺部隐匿性异位分泌ACTH的肿瘤,必要时穿刺活检及影像学检查随访,早期发现并手术切除肺部肿瘤。

Objective:To explore the diagnostic value of imaging for nodular bronchial carcinoid with ectopic adrenocorticotropic hormone syndrome(EAS).Methods:The image data of two cases of patients with small nodular lung carcinoid with EAS in our hospital were retrospectively analyzed,including MRI and PET-CT,chest CT,bilateral inferior petrosal sinus sampling(BIPSS)and pulmonary nodule biopsy.Combined with the patients'clinical manifestation and laboratory examination,the imaging features of these cases were summarized through literature analysis to improve the diagnostic level.Results:Both patients had obvious symptoms of Cushing's syndrome(CS),the adrenocorticotropic hormone(ACTH)of peripheral blood was significantly increased,and cortisol secretion had no circadian rhythm.MRI indicated that pituitary adenomas cannot be ruled out,BIPSS ruled out sources of pituitary ACTH adenoma.Because of the circular nodules found on chest CT,one case of ACTH tumor originated from lung carcinoid was confirmed by puncture biopsy of right upper pulmonary nodules,and the other case of left lower pulmonary nodules was treated by direct thoracoscopic surgery.Two patients had surgical resection of pathology,one was diagnosed with typical low differentiation bronchial carcinoid,the other case was atypical.Conclusions:Bronchial carcinoid is one of the most common causes of EAS.When lung nodules were found in CS patients,and MRI or BIPSS ruled out the source of pituitary ACTH adenoma,ectopic ACTH secretion should be alert to exclude pulmonary bronchial carcinoid.Biopsy or imaging follow-up is necessary,and early detection and surgical removal of the lung tumor are used to gain good curative effect.