74yo M w/ newly diagnosed CLL/SLL. Presented with severe R. hip pain and imaging with a 9cm pelvic mass. Biopsy consistent w/ SLL. He has (+) FLOW for CLL in blood, but normal WBC count/lymphocyte count. TP53 negative. FISH and IGHV pending. Given significant symptoms, was considering treatment with BTKi (zanubrutinib) vs. acalabrutinib/obinutuzumab. In what settings do you typically add obinutuzumab rather than just single agent BTKi.