Bite therapy for DLBCL

Because of age and prior treatments my wife’s lymphoma in pelvic area and breast was treated with Pola-R ; not the standard treatment.
However the PET Scan after 4 cycles showed only partial response. Whereas the pelvic area reacted well and eating and digestion is back to normal the breast mass shows partial response only.
The hospital now started a Polatuzumap plus Monsunetuzumap(bite)treatment.
Any experience to share about breast mass behavior during treatment? Like mass shrinking early and it can be measured by tape or no measurable shrinking because of necrosis-dead cells ?