Table 1.
Study Patient Characteristics Compared According to 5-HIAA Doubling Time
| Entire cohort | 5-HIAA doubling time | P value | ||
|---|---|---|---|---|
| ≥434 days n = 66 (73.3%) | <434 days n = 24 (26.7%) | |||
| Age at inclusion (years) | 53.7 ± 14.7 | 53.6 ± 15.0 | 54.2 ± 14.1 | NS |
| Female gender n (%) | 45 (50.0%) | 29 (43.3%) | 17 (70.8%) | .02 |
| Follow-up duration (months) | 23.3 ± 7.2 | 23.8 ± 7.2 | 22.1 ± 7.3 | NS |
| 24-h urinary 5-HIAA doubling time (days) | 1,361 ± 1,457 | 1,697 ± 1,522 | 296 ± 96 | <.001 |
| Carcinoid syndrome n (%) | 19 (21.1%) | 15 (22.7%) | 4 (16.7%) | NS |
| Primary tumor location | NS | |||
| PNET | 41 (45.6%) | 28 (41.8%) | 13 (56.5%) | |
| SINET | 26 (28.9%) | 20 (29.9%) | 6 (26.1%) | |
| Unknown primary location | 7 (7.8%) | 4 (6.0%) | 3 (13.0%) | |
| Other | 16 (17.8%) | 15 (22.4%) | 1 (4.3%) | |
| Metastatic disease | ||||
| Liver | 32 (37.2%) | 21 (31.8%) | 11 (45.8%) | NS |
| Any | 48 (55.8%) | 35 (53.0%) | 13 (54.2%) | NS |
| Interventions | ||||
| Somatostatin analogues at inclusion | 28 (32.6%) | 22 (33.3%) | 6 (25.0%) | NS |
| Interventions after inclusion | ||||
| Medical therapy | 37 (43.0%) | 28 (42.4%) | 9 (37.5%) | NS |
| Surgery | 15 (17.4%) | 11 (16.7%) | 4 (16.7%) | NS |
| PRRT/liver directed | 6 (7.0%) | 4 (6.1%) | 2 (8.3%) | NS |
| Biochemical biomarkers | ||||
| 24-h urinary 5-HIAA | ||||
| Number of measurements during follow-up | 2.9 ± 1.5 | 2.9 ± 1.4 | 2.1 ± 1.8 | NS |
| Mean value (mg/24 h) | 10.1 ± 17.5 | 8.2 ± 12.8 | 15.6 ± 26.6 | .2 |
| Elevated at inclusion (>8 mg/24 h) n (%) | 22 (25.6%) | 13 (19.7%) | 9 (37.5%) | .06 |
| Serum chromogranin A levels | ||||
| Mean value (ng/mL) | 818 ± 2,056 | 663 ± 1,368 | 1,286 ± 3,385 | NS |
| Elevated at inclusion (>93 ng/mL) n (%) | 42 (48.8%) | 30 (45.5%) | 12 (50.0%) | NS |
| WHO 2010 grade G1–2/G3a n (%) | 47/4 (92.2%/7.8%) | 32/3 (92.8%/8.1%) | 15/1 (93.7%/6.2%) | NS |
Abbreviations: 5-HIAA = 5-hydroxyindoleacetic acid; NS = non-significant; PNET = pancreatic neuroendocrine tumor; PRRT = peptide receptor radionuclide therapy; SINET = small-intestine neuroendocrine tumor; WHO = World Health Organization.
a
Pathology for 3 patients was reported as “well differentiated NET,” 1 patient in the short 5-HIAA DT and 2 patients in the long 5-HIAA DT groups. Those patients were considered as G1–2 NET. Percentages of total number of patients with available tumor grade.