Thanks! Based on your link, I found a couple of very useful links:
- A writeup of basically exactly the question I am facing: http://bsbludwig.com/post/94066296740/what-do-tcgas-rnaseq-files-actually-show#disqus_thread
- More details about the UNC pipeline using RSEM: https://webshare.bioinf.unc.edu/public/mRNAseq_TCGA/UNC_mRNAseq_summary.pdf