肺原发性平滑肌瘤CT征象及病理对照分析

CT appearances and pathologic correlation of primary pulmonary leiomyoma

目的分析肺部原发性平滑肌瘤（PPL）的CT特点，以提高对PPL的认识。方法回顾性分析6例经手术和病理证实的PPL的CT表现及临床特征，并复习文献。结果6例PPL均为单发；肿瘤大小为3．0～8．5cm，外形均呈圆形或卵形，边缘极其光滑；CT平扫均为中等密度，增强后均匀中等度强化4例，不均匀强化2例；1例肿块实质部分明显斑片状强化伴内部囊变，1例假包膜环形强化，未见纵隔淋巴结肿大；6例病理结果均为良性，镜下示平滑肌瘤细胞呈梭形或束状，可见假包膜，1例平滑肌瘤细胞发生玻璃样变性，免疫组织化学检验示平滑肌肌动蛋白（SMA）均标记阳性。结论肺部原发性平滑肌瘤CT表现有特点，但缺乏特异性，确诊仍有赖于病理检查。

Objective To analyze the CT features of primary pulmonary leiomyoma （PPL） and improve the diagnostic ability of PPL. Methods The CT findings and clinical characteristics were retrospectively analyzed in 6 patients with PPL proved by pathology, and the related literatures were reviewed. Results Six PPLs were single lesion from 3.0 to 8.5 cm in size, the shape was round or oval with extremely smooth margin. On CT plain scan, the CT values of all PPL lesions were 25--33 HU, 4 lesions presented homogeneous moderate enhancement （40---60 HU ） and 2 lesions presented inhomogeneous enhancement after contrast administration. A solid lesion showed obviously patchy enhancement with cystic degeneration, 1 lesion presented ring enhancement. All lesions were benign histopathologically, the leiomyoma cells showed spindle shaped or in bundles with pseudocapsule, and with hyaline degeneration in 1 case. Smooth Muscle Actin （SMA） were all marked positive on immunohistochemistry. Conclusions CT findings of PPL have some characteristics, but lack of specificity, the final diagnosis still relies on pathological examination.