I am attempting to call mutations of raw RNA-Seq of single prostate circulating tumor cells (paper) without matching normals.
From cursory research I found that tumor only without a matched normal calls 117x more variants than matched tumor/normal pairs (Appistry). I also found an interesting study that (successfully) discriminated somatic and germline mutations without matching normals but using virtual normal (i.e., normal samples from unrelated individuals) (paper).
My question is, are blood tumor samples treated any differently than tissue tumor samples in respect to calling variants? If there are no normal blood samples available, is filtering against the EVS dataset my best option? Thank you for your time and help.