Characteristic | Total cohort (n=71) | PFS | CTLA4 methylation | Response | ||||
HR (95% CI) | P value | Mean QMS (SD) | P value | ORR (n=20) | No ORR (n=51) | P value χ² test | ||
Median age (range) | 65 (44–79) | 1.03 (0.99 to 1.06) | 0.12 | |||||
Sex—no. (%) | 0.52 | 0.58 | ||||||
Male | 49 (69.9) | Ref group | 73.8 (12.6) | 14 (70.0) | 35 (68.6) | |||
Female | 22 (30.1) | 0.81 (0.50 to 1.71) | 0.81 | 71.4 (17.6) | 6 (30.0) | 16 (31.4) | ||
Sample origin—no. (%) | 0.90 | 0.47 | ||||||
Primary | 58 (81.7) | Ref group | 73.1 (14.8) | 17 (85.0) | 41 (80.4) | |||
Distant metastasis | 13 (13.8) | 0.49 (0.22 to 1.13) | 0.10 | 72.6 (12.1) | 3 (15.0) | 10 (19.9) | ||
RCC histology—no. (%) | 0.010 | 0.31 | ||||||
ccRCC | 67 (94.4) | Ref group | 74.1 (12.8) | 18 (90.0) | 49 (96.1) | |||
Non-ccRCC | 4 (5.6) | 0.63 (0.15 to 2.61) | 0.53 | 55.3 (25.5) | 2 (10.0) | 2 (3.9) | ||
ICB response—no. (%) | 0.030 | ND | ||||||
Objective response* | 20 (28.2) | 0.06 (0.02 to 0.17) | <0.001 | 67.8 (18.5) | 20 (100) | NA | ||
Stable disease | 17 (23.9) | 0.12 (0.05 to 0.27) | <0.001 | 72.4 (10.7) | NA | 17 (33.3) | ||
Progressive disease | 34 (47.9) | Ref group | 79.8 (10.8) | NA | 34 (66.7) |
P values comparing response refer to χ² test. Methylation levels between two or more groups were compared using Mann-Whitney U and Kruskal-Wallis tests, respectively. Cox proportional hazards were tested using Wald test.
*This category included patients with a complete response (n=4) and those with a partial response (n=16). Non-ccRCCs comprised two papillary, one chromophobe, and one medullary RCC. The origin of the included tissue of the distant metastases was lung (n=6), bone (n=4), and one each adrenal gland, skin, and gallbladder metastasis.
ccRCC, clear cell renal cell carcinoma; ICB, immune checkpoint blockade; NA, not applicable; ND, not determined; ORR, overall response rate; PFS, progression-free survival; QMS, Quantitative Methylation Score; RCC, renal cell carcinoma.