阑尾低级别黏液性肿瘤的CT诊断及病理学特征

CT diagnosis and pathology features of appendiceal low-grade mucinous tumor

目的 探讨阑尾低级别黏液性肿瘤（LAMN）的CT表现及病理学特征。方法 回顾性分析11例经手术及病理证实的LAMN的临床资料、CT表现以及组织病理学特点。结果 低级别黏液性肿瘤黏液湖内仅见少量柱状上皮覆盖,具有轻度异型性。CT多表现为长椭圆形囊性占位,最大径约2.5-11cm,长径与短径比值平均为2.3,平均CT值为15-35HU。囊壁薄（3-5.5mm）,厚度不均匀,轻度环形强化,可伴有钙化（n=3）以及分隔条样强化（n=5）,其中3例囊壁破裂形成腹腔假性黏液瘤。结论 LAMN的生物学行为取决于肿瘤性质,CT表现可以显示一定的病理特征,有助于提高其术前诊断准确率。

Objective To investigate the CT manifestations and pathological features of low-grade appendiceal mucinous neoplasm （LAMN）. Methods The clinical data, CT findings and pathological features in 11 patients of LAMN confirmed by surgery and pathology were analyzed retrospectively. Results Only scant mucinous epithelium with low grade dysplasia presented in mucinous pools in LAMN cases. CT usually presented as long eggplant shape with the longest dimension as 2.5 - 11 cm, the ratio of length and width was 2.3 on average. Average attenuation of the cystic masses was 15 -35 HU. All had uniform thin wall （3 - 5.5 ram）, mild ring mural enhancement, accompanied with calcifications （ n = 3 ） or strip-like enhancement （ n = 5 ）. Occasionally, part of the capsule wall ruptured with intra-abdominal pseudomyxoma （ n = 3）. Conclusion LAMN pursues a predictable clinical course based on their pathological nature, CT manifestations show some characteristics of LAMN and play an important role to improve the accurate rate in diagnosis before operative treatment.