Comparison of HER-2 status determined by fluorescence in situ hybridization in primary and metastatic breast carcinoma.

Accurate assessment of HER-2 status is necessary prior to anti-HER-2 antibody (trastuzumab) therapy for metastatic breast carcinoma. However, controversy exists regarding whether to assess HER-2 status in the primary tumor or in metastatic lesions. It is also unclear whether HER-2 status can change during disease progression or after chemotherapy. Breast carcinoma samples from 60 women with known HER-2 status in both primary tumors and paired metastases (locoregional disease, n = 43 patients; distant disease, n = 17 patients) were reviewed retrospectively. Thirty-two patients underwent chemotherapy before their metastatic lesions were sampled, including 18 patients who received neoadjuvant chemotherapy and 14 patients who received adjuvant chemotherapy. The HER-2 gene was examined by fluorescence in situ hybridization either in paraffin-embedded tissue samples (48 primary tumors and 9 metastatic tumors) or in fine-needle aspirates (12 primary tumors and 51 metastatic tumors). HER-2 gene amplification was defined as a HER-2:chromosome 17 signal ratio >/= 2.0. The HER-2 status of primary and metastatic tumors agreed in 58 of 60 patients (97%), including 18 (30%) amplified tumors and 40 (67%) nonamplified tumors. A discrepancy in HER-2 status was observed in specimens from two patients in which HER-2 amplification was detected in the primary tumor but not the metastatic tumors. In one patient, three foci of tumor nodules were found in the same breast; the HER-2 status was assessed in only one of them, which showed amplification; however, HER-2 amplification was not detected in the axillary lymph node metastasis. In another patient, the HER-2 gene was amplified in the primary tumor but not in the liver metastasis. No metastases showed HER-2 amplification without amplification in the primary tumor. Locoregional and distant metastases demonstrated similar concordance rates with their corresponding primary tumors (98% and 94%, respectively). Complete concordance of HER-2 status was found between primary tumors prior to chemotherapy and metastases that were sampled after chemotherapy. The HER-2 status in breast carcinoma generally was stable during metastasis, whether to locoregional or distant sites. Chemotherapy did not modify the HER-2 status in metastatic lesions. Therefore, HER-2 amplification can be evaluated reliably in material from either primary or metastatic tumors in most patients. Further study with larger series is warranted to elucidate the significance of discordant results.

Gong Y ，Booser DJ ，Sneige N 《CANCER》

Discordant HER2 status between primary breast carcinoma and recurrent/metastatic tumors using fluorescence in situ hybridization on cytological samples.

Arihiro K ，Oda M ，Ogawa K ，Tominaga K ，Kaneko Y ，Shimizu T ，Matsumoto S ，Oda M ，Kurita Y ，Taira Y ... -  《-》

Amplification of Her-2/neu gene in Her-2/neu-overexpressing and -nonexpressing breast carcinomas and their synchronous benign, premalignant, and metastatic lesions detected by FISH in archival material.

Xu R ，Perle MA ，Inghirami G ，Chan W ，Delgado Y ，Feiner H ... -  《MODERN PATHOLOGY》

HER2 status in patients with breast carcinoma is not modified selectively by preoperative chemotherapy and is stable during the metastatic process.

The objective of this study was to determine whether HER2 expression levels in breast carcinomas were modified by chemotherapy or during the metastatic process. HER2 expression was analyzed on sequential tissue specimens taken from the primary tumor before patients received preoperative chemotherapy (CT) and from post-CT residual breast tumor or at a metastatic site. The first group of patients included 59 women who presented with T2-T4,N1-N2 breast carcinoma and were treated by preoperative anthracycline-based CT and then underwent surgery. The second group included 44 patients with metastatic breast carcinoma localized to the lung (27 patients) or to the liver (17 patients). HER2 status was determined by immunohistochemistry using an anti-p185(HER/neu) monoclonal antibody and was classified as overexpressed or not overexpressed. Among the patients who received preoperative CT, HER2 overexpression was observed in 15 of 59 patients (25%). A complete pathologic response was observed in 2 of these 15 patients. HER2 still was overexpressed in 11 of 13 remaining residual tumors and was no longer detectable in 2 tumors. In addition, the 29 tumors with no HER2 overexpression before CT remained negative after treatment. In patients with metastatic breast carcinoma, HER2 was overexpressed in 11 of 44 primary tumors (25%). In 9 of these 11 tumors, HER2 overexpression was maintained in the metastases (9 pulmonary metastases and 4 hepatic metastases). In two patients who had low levels of HER2 overexpression in their primary tumors, no staining was observed in the secondary tumor (one pulmonary tumor and one liver tumor). There were no tumors in which the overexpression of HER2 was found only in the metastasis. The current study showed that, in most patients, HER2 overexpression was unchanged after CT and in metastatic sites. No HER2 negative primary tumors became HER2 positive after patients received CT or during the metastatic process. In a few patients, a diminution in the level of HER2 expression was observed after CT or in secondary tumors. This may have been due to a transitory state of altered tumor cells or to the selection of HER2 negative tumor cells clones.

Vincent-Salomon A ，Jouve M ，Genin P ，Fréneaux P ，Sigal-Zafrani B ，Caly M ，Beuzeboc P ，Pouillart P ，Sastre-Garau X ... -  《CANCER》

HER-2/neu amplification by fluorescence in situ hybridization in cytologic samples from distant metastatic sites of breast carcinoma.

Amplification of the HER-2/neu oncogene has been proposed as a target for antibody-based therapies and as a predictor of chemoresponsiveness in advanced breast carcinoma. Few studies have concentrated on HER-2/neu gene evaluation by fluorescence in situ hybridization (FISH) on distant metastatic sites and none have been performed on cytologic samples. The current study evaluated HER-2/neu amplification by FISH on cytologic samples obtained from distant metastatic lesions of breast carcinoma to update HER-2/neu characterization through a safe and easier procedure than biopsy. Twenty-two cytologic samples from distant metastases (12 hepatic samples, 4 skin samples, 3 pleural samples, and 3 peritoneal samples) were submitted to HER-2/neu evaluation by FISH. Seventeen corresponding primary breast tumors also were evaluated by FISH on paraffin histologic sections or on destained archival cytologic smears. Seven of the 22 metastases (32%) were amplified. Amplification was observed in 4 of the 12 liver metastases, in 1of the 3 ascitic fluid specimens, and in 2 of the 4 skin metastases. In all the three pleural fluid specimens, HER-2/neu was unamplified. Matched results from primary and metastatic lesions were obtained in 14 cases (5 were amplified and 9 were unamplified on both primary and metastatic tumors). The results of the current study emphasized the feasibility and advantages of two rapid and very informative techniques, such as fine-needle aspiration biopsy and FISH. Both procedures were performed to ascertain the malignant nature of a suspicious lesion and to obtain predictive markers for response. Since the advent of trastuzumab, the characterization of the molecular profile in metastatic breast disease has become increasingly important for targeted therapy selection.

Bozzetti C ，Personeni N ，Nizzoli R ，Guazzi A ，Flora M ，Bassano C ，Negri F ，Martella E ，Naldi N ，Franciosi V ，Cascinu S ... -  《-》