Hello, I was newly diagnosed with lambda lightchain in June 2025. I had had the disease for some time apparently, was in kidney failure, and had many lesions and vertebral issues. I have responded very well to DRVd, with serum tests showing normal light chain numbers. At six months they did a biopsy but did not get enough material to get an accurate read on MRD. The doc's don't seem to want to do another biopsy because of the serum numbers. Does that make sense? They are continuing with quadruplet therapy for now, beginning cycle 7. They gave me a full two months with no treatment due to stem cell harvesting, shortly after the failed biopsy and other tests required for that. Thoughts??? I don't know why we wouldn't do another MRD biopsy.