乳腺MRI在X线检查乳腺阴性腋淋巴结转移癌阳性患者中的应用价值

目的 探讨乳腺MR检查对临床乳腺触诊和X线检查均为阴性的腋淋巴结转移癌患者寻找其乳腺内原发病灶的应用价值.方法 分析33例以腋淋巴结转移癌为首诊表现(临床乳腺触诊和X线检查均为阴性)患者的乳腺MR影像资料,依据美国放射学会的乳腺影像报告和数据系统MRI标准对所有病变进行分析,并将MRI诊断结果与病理进行对照.结果 33例腋淋巴结转移癌患者中,30例临床行乳腺根治术,其中17例经病理证实为乳腺癌,乳腺MRI检出其中的16例,包括10例肿块性病变和6例非肿块性病变,肿块性病变直径0.5～2.6 cm(平均1.5 cm),直径≤1.5 cm者6例;非肿块性病变包括4例导管性强化和2例段性强化;另1例病理切片发现乳腺癌但乳腺MRI为阴性.其余13例行乳腺根治术患者病理检查未发现乳腺癌灶,其中9例乳腺MRI亦呈阴性表现,另4例MRI提示可疑癌灶.余3例临床未行手术治疗的患者,乳腺MRI亦为阴性.以病理诊断为金标准,MR检出乳腺原发癌灶的敏感度、特异度和准确度分别为94.1%、69.2%和83.3%.结论 相对于一般乳腺癌而言,隐匿性乳腺癌MRI表现更以小灶性的肿块性病变和导管或段性强化的非肿块性病变为常见表现类型.乳腺MR检查对隐匿性乳腺癌的检出具有较高的敏感度和准确度,应作为这类患者的常规检查手段.

Breast MRI in detecting primary malignancy of patients presenting with axillary metastases and negative X-ray mammography

Objective To evaluate the role of breast MRI in detecting the primary malignancy in patients presenting solely with axillary lymph node metastases. Methods Thirty-three patients with axillary lynph node metastases but negative findings on either physical examination or mammography underwent breast MRI to identify occult breast carcinoma. MRI of the breast was assessed according to BI-RADS criteria. The pathologic diagnosis was made according to the standard criteria by the WHO Classification of Tumor. Results Among 33 patients presenting solely with axillary metastases, 30 patients underwent modified radical mastectomy. Primary breast carcinoma was proven in 17 patients. MRI detected lesions in 16 patients, including 10 masses and 6 non-mass lesions. Size of the masses ranged from 0. 5 to 2. 6 cm (mean 1.5 cm). Six lesions were smaller than 1.5 cm in size. Non-mass lesions showed ductal enhancement in 4 cases and segmental enhancement in 2 cases. One patient with tumor detected by histopathology showed no abnormal enhancement on MRI. No tumor was found at mastectomy in the other 13 womeu, and negative MR findings were revealed in 9. Four cases with suspicious enhancement on MRI had no corresponding primary foci on pathology. Three patients didn't undergo surgical procedure. The sensitivity, specificity, and accuracy of MRI in the diagnosis of the primary malignancy were 94. 1%,69. 2%, and 83.3%, respectively. Conclusions Small size of mass and ductal or segmental enhancement of non-mass lesion were common MR features of occult malignancy. MRI showed high sensitivity and accuracy in diagnosing occult breast carcinoma. Breast MRI should be taken in search of occult malignancy in patients with axillary metastases.