Following the command below

query <- GDCquery(project = "TCGA-PRAD", 
              data.category = "Clinical",file.type = "xml")
GDCdownload(query)
clinical.radiation <- GDCprepare_clinic(query, directory = "GDCdata", clinical.info = "patient")

I downloaded the data in CSV file and found there are some patient ID with multiple entries . As an example

TCGA-HC-8265-01B-04R-2303-13 
TCGA-HC-8265-01A-11R-2262-13

My queries:

what does 04R and 11R means ? So as 2303 vs 2262 ?

Is there any manual or weblink to find the details on barID.

Thanks