I recently started working in Cancer Genomics and started to work on cBioPortal. As I was scrolling through the FAQs of cBioPortal I came across this information
"Why do some cancer studies have mutation data and others do not? We store mutation data for published cancer studies. We do not, however store mutation data for provisional cancer data sets generated by TCGA. This is because provisional studies contain preliminary somatic mutations, which per NCI guidelines cannot be redistributed until they have been validated. As each cancer study is published and finalized by the TCGA, we will import the corresponding mutation data."
which got me confused, as down the line I will be looking to work on TCGA data as well
Thus can someone explain to me what is the difference between preliminary somatic mutations, somatic mutations and validated somatic mutations.
Also are all somatic mutations in TCGA are preliminary somatic mutations? If yes, what is the reason behind it and as TCGA is very well used database how to handle this situation.
Can you also tell me other examples in terms of databases where such scenario can happen?
Thanks in advance