How would you manage a patient with Stage IVB DLBCL with refractory disease in the retroperitoneum and spleen after 6 cycles of RCHOP?   

The management of primary refractory stage IV DLBCL is complex and generally not successful. See NCCN Guidelines for details. I would distinguish, however, between those patients who are clinically refractory and those who have clinically responded well but may have residual disease by imaging, i.e....

It is hard to give specific recommendations without more information about the patient and the specific clinical scenario. But general guiding principles: 1) ensure that the disease is indeed primary refractory, with a diagnostically adequate biopsy confirming refractory viable lymphoma. 2) If patie...

Certainly obtaining a biopsy for confirmation of refractory disease is prudent! I would certainly work towards getting approval for CAR-T; current FDA label would require that the patient has failed 2 lines of therapies so, in such patient, I would give no more than 1-2 cycles of salvage chemotherap...