Details

Autor(en) / Beteiligte

• Faratian, D
• Graham, AD
• Rae, F
• Thomas, JS

Titel

Rapid screening of tissue microarrays for Her-2 FISH testing is a safe, accurate, efficient and economic method enabling provision of an entirely FISH-based Her-2 testing service

Ist Teil von

• Cancer research (Chicago, Ill.), 2009-01, Vol.69 (2_Supplement), p.2070

Erscheinungsjahr

2009

Link zum Volltext

Quelle

EZB Free E-Journals

Beschreibungen/Notizen

• Abstract Abstract #2070 Introduction: FISH (fluorescence in situ hybridisation) testing is the gold standard method for Her-2 status assessment in breast cancer yet is only employed in about 30% of tests carried out partly due to cost and labour considerations. Previously we described TMA-based (tissue microarray) testing1 to reducing cost constraints and now describe a rapid screening approach to eliminate unequivocally negative and positive cases and reduce time spent testing.
 Materials and methods: We examined TMAs (6 cores per case) from 89 cases of invasive breast cancer comparing formal FISH scoring with a rapid screening method using systematic examination of the entire core at x100 magnification without formal counting. Each core was screened by two observers and results recorded for each core as positive (P), equivocal (E) or negative (N). Formal counting and rapid screening methods were timed.
 Results: The results are given in Table 1. Where both observers agreed that every core in a particular case was negative (43 cases) or positive (10 cases) the predictive value was 100%. The three “Mixed” Groups were constituted as follows: (1) a predominance of positive observations, (2) a predominance of negative observations and (3) a predominance of equivocal observations. Comparison of the FISH scores for the five observational groups using Student's T Test showed significant or highly significant differences (Range: p=0.02-p=0.0001). Screening each 6 TMA core case at x100 magnification took 2 minutes and formal counting of each case took 12 minutes.
 
 Conclusion: Using stringent criteria we show that rapid screening of TMAs for routine Her-2 FISH testing provides a safe, economical and time-efficient method for the assessment of Her-2 status in breast cancer. The technique ensures that all patients receive gold standard testing. 65% of Her-2 negative cases can be rapid screened and eliminated from formal counting with 100% confidence. Unanimous positive cases can also be appropriately categorised. The remaining cases require formal counting which takes no longer than is normally the case with whole section techniques. The TMAs also provide a valuable resource for future analyses.
 Reference: 1. Graham AD, Faratian D, Rae F, Thomas J St J. Tissue microarray technology in the routine assessment of Her-2 status in invasive breast cancer: a prospective study of the use of immunohistochemistry and fluorescence in situ hybridization. Histopathology 2008; 52: 847-855. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2070.