Serum levels of YKL-40 (μg/L) in patients with cancer and the percentage of patients with elevated serum YKL-40
| Diagnosis | n | Serum YKL-40 | High YKL-40 (%)* | Reference |
|---|---|---|---|---|
| Primary breast cancer† | 271 | 57*** (22-688) | 19 | Johansen et al. (91) |
| Metastatic breast cancer, all‡ | 54 | 80*** (20-560) | 41 | Johansen et al. (83) |
| Soft tissue | 10 | 59 (29-433) | 20 | |
| Bone | 25 | 75*** (21-560) | 35 | |
| Viscera | 19 | 157*** (20-468) | 61 | |
| Metastatic breast cancer, all‡ | 100 | 65*** (20-430) | 31 | Jensen et al. (90) |
| Nodes and skin only | 36 | 51 (20-267) | 9 | |
| Bone | 28 | 61*** (24-310) | 24 | |
| Viscera | 36 | 110*** (21-430) | 57 | |
| Colorectal cancer,‡ all† | 603 | 86*** (27-1,298) | 26 | Cintin et al. (84) |
| Dukes A | 58 | 73** (27-295) | 16 | |
| Dukes B | 223 | 86*** (27-604) | 26 | |
| Dukes C | 175 | 77*** (27-582) | 19 | |
| Dukes D | 147 | 119*** (27-1,298) | 39 | |
| Glioblastoma multiforme | 45 | 130*** (38-654) | 72 | Tanwar et al. (31) |
| Lower grade gliomas | 20 | 101*** (50-225) | 57 | |
| Ovarian cancer, all† | 50 | 94*** (20-517) | 72 | Dupont et al. (81) |
| Ovarian cancer, stages I-II† | 31 | 75*** (20-517) | 65 | Dupont et al. (81) |
| Ovarian cancer, stage III† | 47 | 168*** (32-1,808) | 74 | Høgdall et al. (89) |
| Ovarian cancer, relapse | 73 | 94*** (20-1,970) | 55 | Dehn et al. (87) |
| Small cell lung cancer, all‡ | 131 | 82*** (23-1,188) | 32 | Johansen et al. (92) |
| Local disease | 59 | 71* (23-417) | 22 | |
| Extensive disease | 72 | 101*** (27-1,188) | 40 | |
| Metastatic renal cell cancer | 58 | 235*** (45-1,896) | 83 | Geertsen et al. (88) |
| Metastatic prostate cancer | 153 | 112*** (20-2,080) | 43 | Brasso et al. (86) |
| Metastatic malignant melanoma | 110 | 95*** (20-1,262) | 45 | Schmidt et al. (93) |
NOTE: Values are median (range). *, P < 0.02; **, P < 0.01, and ***, P < 0.001 compared with controls (Mann-Whitney test).
↵* The percentage of patients with elevated serum YKL-40 levels in relation to the serum YKL-40 level in healthy subjects adjusted for age. The normal reference region was calculated on the log-transformed serum or plasma YKL-40 levels obtained from healthy subjects (ages 18-79 years; n = 260 for RIA values and n = 245 for ELISA values). The upper 95th percent confidence limit was chosen for the limit and adjusted for age (103).
↵† Preoperative levels.
↵‡ RIA analysis but the data were corrected to ELISA values (YKL-40ELISA = YKL-40RIA × 0.479). All the other studies used the ELISA method (68).