Nodal response to treatment with idelalisib and rituximab by patient, in primary study. Best nodal response for 50 patients evaluable for lymph node response (14 inevaluable: 12 from lack of baseline adenopathy and 2 from discontinuation before 8 weeks) (black bars) and patients with either del(17p) or TP53 mutations (N = 5; 4 inevaluable patients not shown) (gray bars). Response assessed by physical examination or CT scan according to standard criteria.²⁴  SPD, sum of the products of the perpendicular diameters of measured lymph nodes.