PMID- 23108020
OWN - NLM
STAT- MEDLINE
DCOM- 20130212
LR  - 20151119
IS  - 1532-0979 (Electronic)
IS  - 0147-5185 (Linking)
VI  - 37
IP  - 1
DP  - 2013 Jan
TI  - Clinicopathologic characteristics of HER2 FISH-ambiguous breast cancer at a 
      single institution.
PG  - 120-7
LID - 10.1097/PAS.0b013e31826ab19d [doi]
AB  - BACKGROUND: : The typical algorithm for human epidermal growth factor-2 (HER2) 
      testing is immunohistochemistry (IHC), followed by reflex HER2 fluorescence in 
      situ hybridization (FISH) for HER2 IHC-ambiguous (2+) cases. At our institution, 
      HER2 FISH testing is initially performed as part of routine breast cancer 
      testing, with HER2 FISH-ambiguous (HER2:CEP17 ratio, 1.8 to 2.2) cases reflexed 
      to HER2 IHC. This provides a unique dataset for lesions that may not routinely 
      undergo FISH testing. The clinicopathologic characteristics of HER2 
      FISH-ambiguous cases are described. DESIGN: : The electronic pathology database 
      in our institution was searched for HER2 FISH-ambiguous cases from 2007 to 
      December 2011. Review of clinical and pathologic characteristics was performed. 
      RESULTS: : Sixty cases from 60 patients were reported as HER2 FISH ambiguous. 
      Reflex HER2 IHC testing was performed on all 60 cases, of which 26 were HER2 IHC 
      negative (0 to 1+), 18 were HER2 IHC ambiguous (2+), and 16 were HER2 IHC 
      positive (3+). Of the 46 HER2 FISH-ambiguous patients with available clinical 
      records, 13 (32%) pursued anti-HER2 treatment (10 IHC 3+, 1 IHC 2+, 2 IHC 0 to 
      1+). All were grade II or III ductal carcinomas, with 1 grade III metaplastic 
      carcinoma. CONCLUSIONS: : Reflex HER2 IHC testing after initially ambiguous HER2 
      FISH testing provides definitive HER2 status in a majority of cases (70%). 
      However, a substantial percentage (30%) of HER2 FISH-ambiguous cases is also HER2 
      IHC ambiguous, suggesting an intermediate HER2 biology. Most HER2 FISH-ambiguous 
      patients who received trastuzumab were HER2 IHC 3+, grade III, and had associated 
      high-grade ductal carcinoma in situ. Although not statistically significant and 
      with only minimal follow-up, no recurrences have occurred in those patients 
      treated with trastuzumab (P=0.5754).
FAU - Clay, Michael R
AU  - Clay MR
AD  - Department of Pathology, Stanford Hospital and Clinics, Stanford, CA 94305, USA. 
      mrclay@stanford.edu
FAU - Iberri, David J
AU  - Iberri DJ
FAU - Bangs, Charles D
AU  - Bangs CD
FAU - Cherry, Athena
AU  - Cherry A
FAU - Jensen, Kristin C
AU  - Jensen KC
LA  - eng
PT  - Journal Article
PL  - United States
TA  - Am J Surg Pathol
JT  - The American journal of surgical pathology
JID - 7707904
RN  - 0 (Antibodies, Monoclonal, Humanized)
RN  - 0 (Antineoplastic Agents)
RN  - 0 (Biomarkers, Tumor)
RN  - EC 2.7.10.1 (ERBB2 protein, human)
RN  - EC 2.7.10.1 (Receptor, ErbB-2)
RN  - P188ANX8CK (Trastuzumab)
SB  - IM
MH  - Adult
MH  - Aged
MH  - Aged, 80 and over
MH  - Antibodies, Monoclonal, Humanized/therapeutic use
MH  - Antineoplastic Agents/therapeutic use
MH  - Biomarkers, Tumor/genetics/metabolism
MH  - Breast Neoplasms/*diagnosis/drug therapy/*genetics
MH  - Carcinoma, Ductal, Breast/diagnosis/drug therapy/*genetics
MH  - Carcinoma, Intraductal, Noninfiltrating/diagnosis/drug therapy/*genetics
MH  - Combined Modality Therapy
MH  - Databases, Factual
MH  - Female
MH  - Humans
MH  - Immunohistochemistry/methods
MH  - In Situ Hybridization, Fluorescence
MH  - Mastectomy
MH  - Middle Aged
MH  - Neoplasm Recurrence, Local
MH  - Neoplasm Staging
MH  - Receptor, ErbB-2/*genetics/metabolism
MH  - Reproducibility of Results
MH  - Trastuzumab
MH  - Young Adult
EDAT- 2012/10/31 06:00
MHDA- 2013/02/13 06:00
CRDT- 2012/10/31 06:00
PHST- 2012/10/31 06:00 [entrez]
PHST- 2012/10/31 06:00 [pubmed]
PHST- 2013/02/13 06:00 [medline]
AID - 10.1097/PAS.0b013e31826ab19d [doi]
PST - ppublish
SO  - Am J Surg Pathol. 2013 Jan;37(1):120-7. doi: 10.1097/PAS.0b013e31826ab19d.