MRI对乳腺X线摄影中含成簇微钙化病变的诊断

目的：探讨乳腺磁共振成像对乳腺X线摄影中含成簇微钙化病变的鉴别诊断价值。方法：搜集行乳腺钙化灶立体定位下活检术或术前钩丝定位局切活检术的97例病例,所有患者术前均行乳腺X线摄影和MRI检查且病灶钙化表现为成簇微钙化灶,分析含不同形态成簇微钙化病变的MRI表现及其鉴别诊断价值,并与组织病理学结果进行对照。结果：病灶总数为97个,其中病理结果为良性者73个（75.3%）,恶性24个（24.7%）。良恶性病变乳腺X线上表现均以无定形钙化为主者,分别占57.5%（42/73）、37.5%（9/24）。MRI对含成簇微钙化的恶性病灶诊断的阳性预测值72.4%（21/29）高于乳腺X线摄影28.9%（22/76）（P=0.000）。MRI对含成簇无定形钙化的恶性病灶诊断的阳性预测值66.7%（8/12）高于乳腺X线摄影17.6%（9/51）（P=0.002）。MRI上节段性强化诊断恶性病变的阳性预测值为100.0%（9/9）;无强化对诊断含成簇钙化病变的阴性预测值为100.0%（9/9）。含成簇微钙化的恶性病变早期强化率平均值为109.6%±78.5%,高于良性病变62.8%±25.9%（P=0.000）。结论：MRI对含成簇微钙化特别是无定形成簇微钙化的乳腺病变具有较好的鉴别诊断价值。

MRI in the diagnosis of breast lesions with clustered micro-calcifications showing on mammography

Objective：To assess the value of breast MRI in the differentiatial diagnosis of lesions with clustered micro- calcifications on mammography. Methods： 97 patients, all had mammography and MRI showing clustered micro-calcifica- tions,underwent stereoradiography-guided vacuum-assisted needle core biopsy or excisional biopsy with hook wire localiza- tion. The MRI findings were correlated with pathology and the characteristics of the lesions on MRI which contained differ- ent types of clustered micro-calcifications and their value of differential diagnosis were analyzed. Results： Totally 97 lesions were included, seventy-three （75.3 %） of them were benign and the other 24 （24.7 ~/00 ） were malignant diagnosed by pathol- ogy. Amorphous micro-calcifications were the main feature of micro-calcifications no matter in benign or malignant lesions （57.5 ~ vs 37.5 ~）. The positive predictive value （PPV） of MRI in the diagnosis of clustered micro-calcifications in malig- nant breast lesion was 72.4% （21/29 lesions） ,which was higher than that of mammography （28.9 % ,22/76 lesions） （P-- 0. 000）. The PPV of segmental enhancement on MRI in the diagnosis of malignancy was 100% and the negative predictive value （NPV） of lesions with clustered micro-calcifications yet with no enhancement on MRI was also 100% （9/9 lesions）. The mean of early phase enhancement rate on MRI in the malignant lesion with clustered micro calcifications was 109.6 % 78.5% ,which was higher than that o{ benign lesions （62. 8% 25. 9%）,with statistically significant difference （P= 0. 000）. Conclusions.. MRI is valuable in the differential diagnosis of lesions with clustered micro-calcifications especially clustered amorphous micro-calcifications showing on mammography.