摘要目的 探讨转移至乳腺的恶性肿瘤的临床病理特点、诊断及鉴别诊断.方法 收集2004至2012年间28例转移至乳腺的恶性肿瘤病例,完善临床及预后资料,观察临床病理学特点,EnVision法进行免疫组织化学检测.结果 (1)28例中女性27例,男性1例;发病年龄16 ～ 77岁(平均45.8岁).26例(92.9％)以原发肿瘤初诊,2例(7.1％)以乳腺病变初诊.原发肿瘤至出现乳腺转移的间隔时间为0 ～ 228个月,平均32个月.15例(53.6％)在确诊乳腺转移之前或同时发现其他部位转移.(2)肿瘤大体上表现为境界较清楚的质硬、实性肿块,直径0.6～12.0 cm,平均4.0 cm.28例原发肿瘤组织学类型分别为:肺腺癌8例(28.6％),卵巢高级别浆液性腺癌5例(17.8％),胃腺癌3例(10.7％),直肠腺癌2例(7.1％),胰腺神经内分泌肿瘤和前列腺癌各1例(3.6％),恶性黑色素瘤和间叶源性恶性肿瘤各4例(14.3％),间叶源性恶性肿瘤中胚胎性横纹肌肉瘤3例,上皮样恶性周围神经鞘膜瘤1例.(3)镜下肿瘤多表现原发肿瘤的形态学特征,19例见脉管侵犯.免疫表型与原发肿瘤一致,而乳腺来源标志物囊泡病液体蛋白15和乳腺珠蛋白均阴性.8例转移性肺腺癌甲状腺转录因子-1均阳性,卵巢高级别浆液性腺癌PAX8(5/5)和WT1(4/5)阳性,胃癌CDX2(3/3)和绒毛蛋白(1/3)阳性,2例直肠癌CDX2均阳性,1例胰腺神经内分泌肿瘤突触素和嗜铬粒素A阳性,1例前列腺癌雄激素受体、前列腺特异抗原、P504S均阳性,恶性黑色素瘤HMB45(2/3)和S-100蛋白(3/3)阳性,3例横纹肌肉瘤波形蛋白、结蛋白、myoD1均阳性,1例上皮样恶性周围神经鞘膜瘤S-100蛋白阳性.(4)本组17例有随访资料,中位随访时间54个月;中位生存期24个月.7例死亡.结论 转移至乳腺的恶性肿瘤罕见,多表现原发肿瘤的形态学特征,有时易误诊为原发乳腺癌,需结合临床病史、组织形态学特点及免疫表型等进行诊断和鉴别诊断.

abstractsObjective To investigate the clinicopathologic characteristics and differential diagnosis of the metastases to the breast from non-mammary malignancies.Methods Twenty-eight cases were collected from 2004 to 2012; microscopic pathologic examinations and immunohistochemistry (EnVision method) were performed.Results (1) All except one patients were female,ranging from 16 to 77 years old (average 45.8 years).Twenty-six (92.9％) patients initially presented with the primary site lesions; while the other two (7.1％) patients initially presented with breast lesions.The mean interval from primary diagnosis to detection of metastatic breast lesions was 32 months (0-228 months).Fifteen patients (53.6％) had other metastases detected simultaneously or preceded the breast lesions.(2) Macroscopically,all the tumors were relatively circumscribed,with a mean diameter of 4.0 cm (0.6-12.0 cm).The histological types of the corresponding primary tumors were as follows:eight (28.6％) cases from lung adenocarcinoma,five (17.8％) from high-grade ovarian serous carcinoma,three (10.7％) from gastric adenocarcinoma,two (7.1％) from rectal adenocarcinoma,one (3.6％) from pancreatic neuroendocrine carcinoma,one (3.6％) from prostatic carcinoma,four (14.3％) from melanoma,and four (14.3％) from mesenchymal malignant tumors (three rhabdomyosarcomas and one epithelioid malignant peripheral nerve sheath tumor,MPNST).(3) Histologically,the metastatic tumors showed the morphologic characteristics of the primary tumors.Lymph-vascular invasion was observed in 19 cases.Immunohistochemical features of metastatic tumors were consistent with the primary tumors.Molecular markers for breast such as GCDFP15 and mammaglobin were negative.Metastatic tumors from lung adenocarcinoma expressed TTF-1 (8/8).Ovarian serous carcinoma metastases were positive for PAX8 (5/5) and WT1 (4/5).Gastric adenocarcinoma metastases were positive for CDX2 (3/3) and villin (1/3).Rectal adenoearcinoma metastases were positive for CDX2 (2/2).Pancreatic neuroendocrine tumor metastasis was positive for Syn and CgA (both 1/1).Prostate carcinoma metastasis was positive for AR,PSA and P504S (all 1/1).Melanoma metastases were positive for HMB45 (2/3) and S-100 protein (3/3).Rhabdomyosarcoma metastases were positive for vimentin,desmin and myoD1 (all 3/3).MPNST metastasis was positive for S-100 protein (1/1).(4) Follow-up data was available in 17 patients,with median follow-up time 54 months.The median survival from diagnosis to breast metastasis was 24 months.Seven of 17 patients died.Conclusions Metastases to the breast from non-mammary malignancies are rare and show pathologic features of primary tumors.It is usually presumed to be a primary breast carcinoma.Histopathologic features and clinical history in conjunction with the immunohistochemical results should be considered in differentiating a secondary mass from a primary breast carcinoma.