Table 2.
Predictive factors associated to the absence of complete BM response in the 145 patients of the RAI therapeutic efficacy analysis cohort
| Complete BM-response | Univariate † | Multivariate†† | OR | |||
|---|---|---|---|---|---|---|
| Variables | No (n = 99) | Yes (n = 46) | p | p | 95% CI | |
| Prognostic factors available at the moment of first RAI course | ||||||
| Sex (male) | 44 (81.5%) | 10 (18.5%) | 0.00849 | |||
| Age (years)* | 62 [53–68] | 46 [31–65] | 0.000224 | |||
| Age > 55 years | 68 (81.9%) | 15 (18.1%) | 0.0000437 | 0.157 | 2.8 [0.7–10] | |
| TNM T stage | ||||||
| T1 | 12 (11%) | 10 (22%) | 0.24 | |||
| T2 | 26 (27%) | 15 (33%) | ||||
| T3 | 43 (45%) | 16 (36%) | ||||
| T4 | 16 (17%) | 4 (9%) | ||||
| TNM N1 stage | 34 (45%) | 10 (28%) | 0.0946 | |||
| Histology/cancer type | 0.00000629 | 0.54 | 0.4 [0.1–2] | |||
| WDTC | 47 (43%) | 40 (85%) | ||||
| PTC | 14 (14.1%) | 27 (27.3%) | 0.000436 | |||
| FTC | 33 (33.3%) | 13 (13.1%) | ||||
| PDTC | 31 (34%) | 4 (11%) | ||||
| Aggressive variants | 21 (23%) | 2 (4%) | ||||
| Necrosis | 30 (46%) | 5 (12%) | 0.00142 | |||
| Vascular invasion | 59 (72%) | 20 (47%) | 0.01721 | |||
| Synchronous BM | 70 (61%) | 39 (83%) | 0.0679 | |||
| Time DTC-BM diagnosis * | 0 [0;3] | 0 [0;0] | 0.007 | |||
| Extra-skeletal metastasis | 56 (56%) | 11 (26%) | 0.000242 | 0.0052 | 9.1 [2.2–50] | |
| SRE at diagnosis | 52 (46%) | 34 (28%) | 0.0147 | |||
| High-risk fracture | 76 (77%) | 27 (60%) | 0.0256 | |||
| Number of BM sites | 0.332 | |||||
| 1 | 31 (32%) | 20 (43%) | ||||
| 2–5 | 45 (45%) | 16 (36%) | ||||
| > 5 | 23 (23%) | 10 (21%) | ||||
| RAI uptake in one or more BM | 82 (73%) | 44 (96%) | 0.0332 | |||
| RAI uptake in all BM | 69 (65%) | 39 (93%) | 0.00954 | 0.062 | 0.1 [0.01–1.7] | |
| Evidence of BM on cross sectional imaging | 80 (83%) | 20 (43.5%) | 0.00000613 | 0.598 | 1.5 [0.3–6.3] | |
| BM size* (cm) | 3.4 [2-6] | 3 [2.3–4.67] | 0.25 | |||
| Osteolysis | 66 (79%) | 13 (42%) | 0.000309 | |||
| FDG PET/CT uptake in BM | 67 (85%) | 8 (35%) | 0.000000575 | 0.0236 | 5 [1.3–25] | |
| Tg at diagnosis (ng/ml)** | 1325 [107.5–6502.5] | 12.5 [3.9–31.1] | 0.000000796 | |||
| Factors available during follow-up | ||||||
| Median follow-up time (years) [range] | 7 [4–10.2] | 7 [4–10.5] | 0.855 | |||
| RAI number of cures* | 3 [1-5] | 2 [2, 3] | 0.00254 | |||
| Cumulative RAI activity* | 400 [200–600] | 200 [200–375] | 0.00209 | |||
| RAI Refractory during follow-up | 70 (70.7%) | 3 (6.5%) | 6.28*10^−13 | |||
| New BM during treatment | 55 (55.6%) | 5 (10.8%) | 3.56*10^−08 | |||
| Occurrence of SRE | 73 (73.7%) | 11 (23.9%) | 1.55*10^–08 | |||
| Numbers of SRE per patient* | 2 [1-3] | 0 [0–1] | 3.3*10^−9 | |||
| Anti-resorptive agents | 32 (32.3%) | 6 (13%) | 0.0151 | |||
| BM surgery | 53 (53.5%) | 8 (17.4%) | 0.0000408 | |||
| Radiotherapy or Thermal ablation | 72 (72.7%) | 9 (19.6%) | 1.97*10^−9 | |||
| Cementoplasty | 57 (57.6%) | 10 (21.7%) | 0.0000439 | |||
| Systemic treatment | 0.00005 | |||||
| None | 72 (72.7%) | 46 (100%) | ||||
| Chemotherapy | 10 (10.1%) | 0 | ||||
| TKI | 17 (17.3%) | 0 | ||||
| All-cause deaths | 54 (54.5%) | 5 (10.8%) | 4.18*10^−07 | |||
OR, odds ratio; TNM, tumor node metastasis; WDTC, well-differentiated thyroid carcinoma; PDTC, poorly differentiated thyroid carcinoma; PTC, papillary thyroid carcinoma; FTC, follicular thyroid carcinoma; BM, bone metastases; DTC, differentiated thyroid carcinoma; RAI, radioactive iodine; FDG PET, fluorodesoxyglucose-positron emission tomography; RAI, radioactive iodine; SRE, skeletal-related events; Tg, thyroglobulin; TKI, tyrosine kinase inhibitor. *mean and standard deviation. **median and range. †Wilcoxon test/chi-square test or Fisher exact test. †† Logistic regression