PFS2 according to the 2L BTKi MIPI in the main cohort. (A) High-, intermediate-, and low-risk categories of PFS2 in the main cohort according to the 2L BTKi MIPI in cases with complete data (n = 105). (B) High-, intermediate-, and low-risk categories of PFS2 in the main cohort according to the 2L BTKi MIPI in all cases (n = 160; missing individual Ki67 or MIPI values were coded as low).