SR is a rare phenomenon occurring in 1 in 80 000 to 1 in a 100000 of all cancer patients.It occurs more common in low grade lymphomas, ie, follicular, marginal cell and cutaneous lymphoma , It is extremely rare in DLCBL.In low grade lymphoma it can be as high as 10 to 20 percent.
However many eventually return .No one knows the reason .Some postulate it is your own immune system that may interact with certain markers.I have personally witnessed this in end stage ovarian cancer.,.
Rarely it can be related to a the wrong diagnosis .especially in centers that don’t have a dedicated lymphoma pathologist or the tissue sample was not optimal ..From an imaging perspective many , many things can look and act like lymphoma including pet scans
Best regards
Frank

Frank9,
Thank you for your indepth explanations. You are a blessing to this site and all of us. Kelly

Any time

Yes, I agree with Kelly. Thank you Frank9!