<prompt> In cases of Cancer breast with Her-2 neu amplification when will you do FISH?HER 2 neu 1HER 2 neu 2Irrespective of Her 2 neuHER 2 neu 3  <response>: Ans. b HER 2 neu 2Ref NCCN Guidelines for Cancer breast HER 2 Status of the cancer breast is routinely done by IHC study with values from 0 to l, 2 and 3. Recently FISH Fluorescence Insitu Hybridization is used to detect HER 2 amplification and advised for IHC HER 2 positive cases of values 2 onwards. 20 incidence is detected and treated by Trastuzumab HER 2 receptor inhibitor 