PMID- 16040300
OWN - NLM
STAT- MEDLINE
DCOM- 20050915
LR  - 20220317
IS  - 0002-9173 (Print)
IS  - 0002-9173 (Linking)
VI  - 124
IP  - 2
DP  - 2005 Aug
TI  - Analysis of intratumoral heterogeneity and amplification status in breast 
      carcinomas with equivocal (2+) HER-2 immunostaining.
PG  - 273-81
AB  - Fluorescence in situ hybridization (FISH) and immunohistochemical analysis for 
      assessment of HER-2 status in breast carcinomas are discordant in a significant 
      proportion of cases with equivocal (2+) immunostaining. To evaluate the role of 
      intratumoral heterogeneity and degree of amplification, we performed additional 
      HER-2 immunostains and FISH on tumor-bearing blocks from 20 invasive breast 
      carcinomas with immunohistochemical scores of 2+ with gene amplification and in 
      18 cases without amplification. Of the amplified cases, 11 (55%) had a 3+ 
      immunohistochemical score on at least 1 additional slide, 8 (40%) remained 2+, 
      and 1 (5%) had a slide scored 1+. All cases rescored 3+ showed high-level 
      amplification in original and repeated FISH; cases remaining 2+ had a 
      heterogeneous FISH profile (low-level amplification or a mosaic mixture of 
      high-level amplified and nonamplified cells) in original and repeated FISH. Of 
      nonamplified cases, 13 (72%) had a 1+ score on at least 1 additional slide, 4 
      (22%) remained 2+, and 1 (6%) had 1 slide scored 3+. In the nonamplified cases, 
      17 (94%) showed no amplification in repeated FISH. Significant intratumoral 
      heterogeneity and minimal (low-level) HER-2 amplification account for many breast 
      cancers with 2+ HER-2 protein expression.
FAU - Lewis, Jason T
AU  - Lewis JT
AD  - Division of Anatomic Pathology, Department of Laboratory Medicine and Pathology, 
      Mayo Clinic, Rochester, MN, USA.
FAU - Ketterling, Rhett P
AU  - Ketterling RP
FAU - Halling, Kevin C
AU  - Halling KC
FAU - Reynolds, Carol
AU  - Reynolds C
FAU - Jenkins, Robert B
AU  - Jenkins RB
FAU - Visscher, Daniel W
AU  - Visscher DW
LA  - eng
PT  - Journal Article
PL  - England
TA  - Am J Clin Pathol
JT  - American journal of clinical pathology
JID - 0370470
RN  - EC 2.7.10.1 (Receptor, ErbB-3)
SB  - IM
MH  - Adult
MH  - Aged
MH  - Aged, 80 and over
MH  - Breast Neoplasms/*genetics/metabolism/*pathology
MH  - Carcinoma, Ductal, Breast/genetics/metabolism/pathology
MH  - Carcinoma, Intraductal, Noninfiltrating/genetics/metabolism/pathology
MH  - Carcinoma, Lobular/genetics/metabolism/pathology
MH  - Female
MH  - *Gene Amplification
MH  - Humans
MH  - Immunohistochemistry
MH  - In Situ Hybridization, Fluorescence
MH  - Middle Aged
MH  - Receptor, ErbB-3/*metabolism
EDAT- 2005/07/26 09:00
MHDA- 2005/09/16 09:00
CRDT- 2005/07/26 09:00
PHST- 2005/07/26 09:00 [pubmed]
PHST- 2005/09/16 09:00 [medline]
PHST- 2005/07/26 09:00 [entrez]
AID - J9VXABUGKC4Y07DL [pii]
AID - 10.1309/J9VX-ABUG-KC4Y-07DL [doi]
PST - ppublish
SO  - Am J Clin Pathol. 2005 Aug;124(2):273-81. doi: 10.1309/J9VX-ABUG-KC4Y-07DL.