Post on 30-Dec-2015
description
FNA-TG of Neck Nodes in the Patients with PTC is Affected by Serum Concentration of TSH And Thyroglobulin
JH Moon1, YI Kim2, JA Lim3, HS Choi3, SW Cho3, KW
Kim4, JC Paeng2, YJ Park3, KH Yi5, DJ Park3, J-K Chung2
1Department of Internal Medicine, Seoul National University Bundang Hospital, Seoul
National University College of Medicine2Department of Nuclear Medicine, Seoul National University College of Medicine3Department of Internal Medicine, Seoul National University Hospital, Seoul National
University College of Medicine4Seoul National University Healthcare System Kangnam Center, Seoul National
University College of Medicine5SMG-SNU Boramae Medical Center, Seoul National University College of Medicine
Statement of interest: None
• Measuring the concentration of thyroglobulin directly in the washout of the needle used in FNAC
FNA-Tg
• Factors affecting FNA-Tg and resulting in the discrepancy between the final diagnosis and FNA-Tg
Various cut-off value (0.93-50 ng/ml)
•To suggest an optimal cut-off value of FNA-Tg to determine malignant LN with a large number of cases from PTC patients
•To find out parameters affecting FNA-Tg and the diagnosis using FNA-Tg
- Evaluation of discrepant results
Study objectives
Subjects and Methods
Patient characteristics and FNA-Tg according to the final diagnosis
Final diagnosisp-value
Malignancy Benign
Lymph nodes (n) 190 338
Patients
Sex (male/female, %) 30.5/69.5 24.3/75.7 0.228*
Age (year) 52.6 ± 15.0 49.5 ± 12.4 0.017†
Primary tumor
Size (mm) 18.0 ± 10.9 13.5 ± 11.4 < 0.001†
Multiplicity (yes/no, %) 69.5/30.5 63.1/36.9 0.203* Lymph nodes metastasis (yes/no, %) 87.0/13.0 59.3/40.7 < 0.001*
Lymphatic invasion (yes/no, %) 51.0/49.0 27.2/72.8 < 0.001*
Vascular invasion (yes/no, %) 32.3/67.7 15.7/84.3 < 0.001* Extrathyroid extension (yes/no, %) 90.3/9.7 71.6/28.4 < 0.001*
FNA-Tg (ng/ml) 521.2 (3676.8) 0.1 (0.2) < 0.001‡
Serum Tg (ng/ml) 1.4 (9.5) 0.2 (0.4) < 0.001‡
FNA-Tg - Serum Tg (ng/ml) 333.3 (2397.7) 0.0 (0.3) < 0.001‡
Data are expressed as mean ± SD or median (interquatile range).
FNA-Tg, thyroglobulin in the needle washout fluid of fine-needle aspiration cytology
*Derived from a Chi-square test.
†Derived from a Student's T test.
‡Derived from a Mann-Whitney U test.
Validation of Cut-off value(FNA-Tg vs. FNA-Tg – serum Tg)
Included lymph nodes
Cut-off valueSensitivity
(%)Specificity
(%)FNA-Tg(ng/ml)
FNA-Tg - serum Tg
(ng/ml)
Surgically resected LNs only (n =165)1.11 93.8 88.9
0.15 87.4 89.7
Surgically resected LNs and LNs F/U for 36 months or more (n = 255)
1.11 94.1 95.0
0.40 87.3 95.3
Surgically resected lymph nodes and LNs F/U for 24 months or more (n = 377)
0.99 94.2 95.5
0.40 87.7 96.1
Surgically resected lymph nodes and LNs F/U for 12 months or more (n = 528, all cases)
1.0 93.2 95.9
0.48 85.7 96.7
Diagnostic performance
ROC of FNA-Tg for Dx of malig. LN. in all casesOptimal cut-off value: 1.0 ng/ml AUC: 0.967 (95% CI 0.949-0.984)
Diagnosis modality Sensitivity (%) Specificity (%)
FNAC 83.6* 98.2*
FNA-Tg (cut off value, 1.0 ng/ml) 93.2* 95.9*
FNA-Tg (1.0 ng/ml) + FNAC 98.4 94.4
*p < 0.05 vs. FNA-Tg + FNAC, derived from a McNemar test.
The cut-off value of FNA-Tg according to the presence of thyroid gland
Prior to thyroidectomy
After thyroidectomy
2.24 ng/ml (95.0%, 96.3%)AUC: 0.987 (95% CI 0.975-0.999)
1.09 ng/ml (90.8%,
96.5%)AUC: 0.956 (95% CI 0.932-0.980)
FNA-Tg, serum Tg and TSH according to the presence of thyroid gland
FNA-Tg
201.0 (3884.77)
0.1 (2.90)
All cases Malignant cases Benign cases
Serum TgCorrelated
ρ = 0.383p < 0.001
Correlatedρ = 0.228p = 0.004
Correlatedρ = 0.210p < 0.001
Serum TSHCorrelated
ρ = 0.210p < 0.001
Correlatedρ = 0.335p < 0.001
Not correlatedρ = 0.075p = 0.183
Correlation of FNA-Tg with serum Tg or TSH
Correlation of FNA-Tg with TgAb
TgAb - TgAb +
0.1 (7.15)
0.3 (71.46)
Serum TSH and Tg on the diagnosis from FNA-Tg
Logistic regression analysis of serum TSH and Tg with the diagnosis using FNA-Tg cut-off value 1.0 ng/ml
Odd ratio
95% confidence interval for odds ratio p-value
Lower Upper
Serum TSH 1.171 1.038 1.321 0.01
Serum Tg 1.035 1.012 1.059 0.003
The dependent variable was the diagnosis using ENA-Tg cut off value 1.0 ng/ml, and the independent vari-ables
were serum TSH and Tg levels.
Odd ratio
95% confidence interval for odds ratio p-value
Lower Upper
No serum TSH suppres-sion 2.871 1.794 4.595 < 0.001
Serum Tg presence 1.980 1.261 3.109 0.003
The dependent variable was the diagnosis using ENA-Tg cut off value 1.0 ng/ml, and the independent vari-ables
were no serum TSH suppression (serum TSH ≥ 0.4 mU/l) and serum Tg presence (serum Tg ≥ 0.2 ng/ml).
Logistic regression analysis of serum TSH suppression and serum Tg presence with the diagnosis using FNA-Tg cut-off value 1.0 ng/ml
Clinical implications
•Optimal cut-off value of FNA-Tg was 1.0 ng/ml
•FNA-Tg + FNAC showed better diagnostic rate than FNAC or FNA-Tg alone.
•FNA-Tg was correlated with serum Tg and TSH, not with TgAb.
•The diagnosis using FNA-Tg can be affected by serum TSH and Tg levels.
Summary
• The combination of FNAC and FNA-Tg can complement the low sensitivity of FNAC alone.
• TSH suppression and the presence of serum Tg should be considered for accurate FNA-Tg-based diagnosis of metastatic malignant LNs in PTC patients.
Conclusion