1- TP53 a mediator of stress response and guards the genome from stress related changes of various kind 
2- TP 53 mutation status in various tumors. The mutated allele frequencies are higher than we expect them to be
3-Apart from FISH and sequencing, microarray can also detect TP 53 mutation
4- if you test only by FISH, then in comparison to NGS there is a possibility of missing 25-30% cases with mutated TP53 cases at the time of first therapy in CLL
5- TP53 positivity rates rise with each relapse of CLL. Do not forget to test for this before each next line of therapy. The chemoimmunotherapy is ineffective in such cases. However, this step is useful only when access to novel agent is there.
6 Lastly, from lab point of view ERIC recommends that > 10% mutated subclone for TP53 is reportable ?clinically actionable
