甲状腺多发结节内的乳头状癌CT诊断

CT Diagnosis of Papillary Carcinoma in Multiple Thyroid Nodules

目的:探讨甲状腺内多发结节的CT征象,以提高对甲状腺乳头状癌的正确诊断。方法:回顾性分析89例甲状腺多发病变中均有甲状腺微乳头状癌CT影像特点。结果:89例病人共检出甲状腺结节266枚,其中乳头状癌结节89枚,结节性甲状腺肿156枚、慢性淋巴细胞性甲状腺炎10例、甲状腺腺瘤11枚。结节形态不规则者80枚,圆形或椭圆形者151枚,增强后边界清晰148枚;高强化39枚。甲状腺乳头状癌61枚结节显示"甲状腺边缘中断征"或"咬饼征"。而该征象在5枚结节性甲状腺肿中可见。增强后甲状腺乳头状癌病灶范围缩小/模糊71枚;出现假包膜10枚,病灶强化时可见"强化残圈征",外侧边缘包膜呈波浪状改变者50枚。结节性甲状腺肿出现:a.整体囊变12枚b.囊变为主51枚c.部分囊变60枚d.高密度囊肿33枚。腺瘤11枚结节平扫均为低密度结节,边界清晰,持续性明显强化。桥本病11例密度近似周围肌肉,均匀轻度强化。共有66枚结节伴发钙化,其中微钙化13枚,簇状钙化6枚,粗颗粒或斑片状钙化3枚,呈弧形、环形钙化位于瘤体内部的11枚,位于边缘的33枚。结论:平扫呈不规则低密度、甲状腺边缘中断征或咬饼征、磨砂玻璃样强化、晕带征、微钙化以及簇状钙化是甲状腺乳头状癌具有特异性的CT征象。

Objective:To improve the diagnostic accuracy of thyroid papillary carcinoma by evaluating the CT features of multiple nodules in the thyroid.Methods:The CT features of multiple thyroid nodules combined with papillary carcinoma in 89 patients were retrospectively analyzed.Results:A sum of 266 nodules were detected in 89 patients. Among the multiple nodules, there were 89 papillary carcinoma, 156 thyroid nodular goiter, 10 chronic lymphocytic thyroiditis and 11 thyroid adenoma. CT imaging showed 80 nodules with irregular shape, 151 with round or oval shape. After enhancement, 148 nodules showed clear margin and 39 nodules showed markedly enhancement. 61 nodules confirmed of papillary carcinoma showed "margin interrupt sign" or "bite bread sign", and this sign was also present in 5 nodular goiters. After enhancement 71 nodules of papillary carcinoma showed margin narrowed or blurred, 10 nodules showed pseudocapsule and 50 nodules showed waved shape in the outside edge capsule. The CT features of nodular goiter were: completely cystic change in 12 nodules, mostly cystic change in 51 nodules, partially cystic change in 60 nodules and high density cysts in 33 nodules. In the 11 nodules of thyroid adenomas, they showed hypo-density nodules with clear margin and persistent markedly enhancement. In the 11 cases of Hashimoto’s thyroiditis, they showed similar density to adjacent muscles and mild enhancement. Calcification was seen in 66 nodules which including 13 micro-calcification, 6 cluster calcification and 3 granular or patch-like calcification. Arc or ring-like calcifications in 11 nodules were located inside the nodules, while 33 were in the margin.Conclusion:Nodules with irregular shape, hypo-density in plain scan, margin interrupt sign or bite bread sign, relatively low enhancement, pseudocapsule, and micro-or cluster calcification are characteristic features of papillary carcinoma.