Fig. 1Kaplan-Meier disease-free estimate curves of significant factors for papillary thyroid cancer recurrence. (A) Multifocality. (B) Lymph node metastases at presentation. (C) Distant metastases at presentation. (D) Age >45. (E) Histologic type. (F) Postsurgical radioactive iodine (RAI) ablation.
Fig. 2Kaplan-Meier disease-free estimate curves of significant factors for follicular thyroid cancer recurrence. (A) Distant metastases at presentation. (B) Postsurgical radioactive iodine (RAI) ablation.
Table 1Baseline Characteristics of Filipino Patients with Recurrent Well-Differentiated Thyroid Cancer
Characteristic |
Papillary thyroid cancer (n=214) |
Follicular thyroid cancer (n=23) |
Age, yr |
44.3±13.4 |
48.9±11.4 |
Sex male, % |
20.1 |
13.0 |
Lymph node involvement at presentation |
85 (39.7) |
6 (26.1) |
Tumor size, cm |
3.3±2.0 |
3.27±2.0 |
Interval between recurrence and thyroidectomy, mo |
13±6 |
26±15 |
Follow-up duration, mo |
53±12 |
83±23 |
Repeated surgery |
47 (22.0) |
6 (26.1) |
Repeated radioactive iodine therapy |
110 (51.4) |
12 (52.2) |
External beam radiotherapy |
7 (3.3) |
5 (21.7) |
Chemotherapy |
1 (0.4) |
0 |
Mortality |
2 (0.9) |
2 (8.7) |
Table 2Predictive Variables for Recurrence in Filipinos with Well-Differentiated Thyroid Cancer
Variable |
Presence of recurrence |
Absence of recurrence |
Odds ratio |
P value <0.05 |
Papillary thyroid cancer |
|
|
|
|
Number |
214 |
435 |
|
|
Male sex |
43 (20.1) |
53 (12.2) |
1.96 |
<0.001 |
Age >45 yr |
110 (51.4) |
184 (42.3) |
1.60 |
0.001 |
Family history |
4 (1.9) |
4 (0.9) |
1.50 |
0.422 |
Smoking history |
39 (18.2) |
32 (7.4) |
2.66 |
<0.001 |
Alcohol intake |
48 (22.4) |
41 (9.4) |
2.89 |
<0.001 |
Diabetes |
20 (9.4) |
35 (8.1) |
1.17 |
0.521 |
Hypertension |
59 (27.6) |
108 (24.8) |
1.11 |
0.490 |
Hashimoto's thyroiditis |
8 (3.7) |
32 (7.4) |
0.66 |
0.257 |
Graves' disease/hyperthyroidism |
12 (5.6) |
29 (6.7) |
1.11 |
0.710 |
Second malignancy |
6 (2.8) |
14 (3.2) |
0.70 |
0.384 |
Tumor size >4 cm (T3) |
65 (30.4) |
86 (19.8) |
1.80 |
<0.001 |
Multifocality of cancer |
60 (28.0) |
92 (21.2) |
1.62 |
0.002 |
Bilateral lobe involvement |
45 (21.0) |
69 (15.9) |
1.70 |
0.002 |
Follicular variant histology |
19 (8.9) |
82 (18.9) |
0.55 |
0.013 |
Tall cell variant histology |
3 (1.4) |
2 (0.5) |
3.70 |
0.025 |
Oncocytic variant histology |
1 (0.5) |
1 (0.2) |
2.15 |
0.444 |
Lymph node metastases at presentation (N1) |
119 (55.6) |
75 (17.2) |
4.45 |
<0.001 |
Distant metastases at presentation (M1) |
14 (6.5) |
10 (2.3) |
3.35 |
<0.001 |
High MACIS score (>7) |
24 (11.2) |
19 (4.4) |
2.86 |
<0.001 |
Incomplete thyroidectomy |
14 (6.5) |
24 (5.5) |
0.94 |
0.804 |
Postsurgical radioactive ablation |
130 (60.6) |
335 (77.0) |
0.43 |
<0.001 |
TSH suppression <0.1 mIU/L |
87 (40.9) |
53 (12.6) |
1.36 |
0.761 |
Follicular thyroid cancer |
|
|
|
|
Number |
23 |
56 |
|
|
Male sex |
3 (13.0) |
4 (7.1) |
3.15 |
0.077 |
Age >45 yr |
14 (60.9) |
25 (44.6) |
2.50 |
0.043 |
Family history |
1 (4.3) |
2 (3.6) |
<0.01 |
1.000 |
Smoking history |
2 (8.7) |
5 (8.9) |
2.93 |
0.163 |
Alcohol intake |
2 (8.7) |
8 (14.3) |
1.16 |
0.844 |
Diabetes |
2 (8.7) |
2 (3.6) |
3.67 |
0.089 |
Hypertension |
4 (17.4) |
16 (28.6) |
0.67 |
0.470 |
Hashimoto's thyroiditis |
1 (4.3) |
1 (1.8) |
<0.01 |
1.000 |
Second malignancy |
1 (4.3) |
1 (1.8) |
<0.01 |
1.000 |
Tumor size >4 cm (T3) |
5 (21.7) |
20 (35.7) |
0.86 |
0.775 |
Multifocality of cancer |
3 (13.0) |
3 (5.4) |
4.25 |
0.027 |
Bilateral lobe involvement |
3 (13.0) |
2 (3.6) |
5.54 |
0.009 |
Lymph node metastases at presentation (N1) |
3 (13.0) |
3 (5.4) |
1.63 |
0.435 |
Distant metastases at presentation (M1) |
9 (39.1) |
1 (1.8) |
21.56 |
<0.001 |
Incomplete thyroidectomy |
7 (30.4) |
1 (1.8) |
5.32 |
<0.001 |
Postsurgical radioactive ablation |
11 (47.8) |
47 (83.9) |
0.29 |
0.004 |
TSH suppression <0.1 mIU/L |
15 (65.2) |
45 (80.4) |
0.686 |
0.410 |
Table 3Multivariate Logistic Regression Analysis of Significant Risk Factors for Recurrence in Filipinos with Well-Differentiated Thyroid Cancer
Risk factor |
Odds ratio (95% CI) |
P value |
Papillary thyroid cancer |
|
|
Age >45 yr |
1.44 (1.09-1.89) |
0.010 |
Lymph node metastases at presentation (N1) |
4.00 (2.99-5.34) |
<0.001 |
Distant metastases at presentation (M1) |
2.78 (1.59-4.84) |
<0.001 |
Multifocality |
1.43 (1.05-1.95) |
0.023 |
Follicular variant histology |
0.60 (0.37-0.97) |
0.037 |
Postsurgical radioactive ablation |
0.31 (0.24-0.42) |
<0.001 |
Follicular thyroid cancer |
|
|
Distant metastases at presentation (M1) |
19.4 (6.28-59.96) |
<0.001 |
Postsurgical radioactive ablation |
0.41 (0.17-0.98) |
0.044 |
Table 4Comparison of Multivariate Analyses for Recurrence of Well-Differentiated Thyroid Cancer across Different International Studies
Risk factor |
Our data |
Palme et al. (2004) [15] |
Baek et al. (2010) [7] |
Kim et al. (2014) [16] |
Ito et al. (2012) [17] |
Age |
√ |
X |
X |
X |
√ |
Male sex |
X |
√ |
X |
√ |
√ |
Tumor size |
X |
√ |
X |
X |
√ |
Nodal metastases |
√ |
√ |
√ |
√ |
√ |
Distant metastases |
√ |
√ |
NA |
√ |
NA |
Histologic type |
√ |
X |
NA |
√ |
NA |
Multifocality |
√ |
X |
X |
X |
NA |
Incomplete thyroidectomy |
X |
√ |
X |
X |
NA |
Postsurgical radioactive iodine ablation |
√ |
X |
NA |
NA |
NA |