Value of thyroglobulin combined with ultrasound-guided fine-needle aspiration cytology for diagnosis of lymph node metastasis of thyroid carcinoma

Table 1 Ultrasonographic findings of cervical lymph node metastases in positive and negative patients, n (%)

Pathological results	n	Cortical centripetal thickening		Hypoechogenicity of cortex and medulla		Long diameter/short diameter < 2		Partial liquefaction or fusion of the lymph nodes		Rich internal blood supply		Hilum deletion
		Yes	No	Yes	No	Yes	No	Yes	No	Yes	No	Yes	No
Positive cervical lymph node metastasis	124	69 (55.65)	55 (44.35)	55 (44.35)	69 (55.65)	67 (54.03)	57 (45.97)	39 (31.45)	85 (68.55)	63 (50.81)	61 (49.19)	32 (25.81)	92 (74.19)
Negative cervical lymph node metastasis	85	34 (40.00)	51 (60.00)	26 (30.59)	59 (69.41)	30 (35.29)	55 (64.71)	14 (16.47)	71 (83.53)	31(36.47)	54 (63.53)	11 (12.94)	74 (87.06)
χ2 value		4.939		4.027		7.120		5.980		4.188		5.108
P value		0.026		0.045		0.008		0.014		0.041		0.024

Table 2 Comparison of fine-needle aspiration thyroglobulin values between positive and negative patients with cervical lymph node metastasis (mean ± SD)

Pathological results	n	FNA-Tg (ng/mL)	t value	P value
Positive cervical lymph node metastasis	124	1.56 ± 0.47	14.526	0.000
Negative cervical lymph node metastasis	85	0.77 ± 0.21

FNA-Tg: Fine-needle aspiration thyroglobulin.

Table 3 The comparison of pathological diagnosis results between single and combined diagnosis of fine-needle aspiration and fine-needle aspiration thyroglobulin

FNA	Pathological results		Total	FNA-Tg	Pathological results		Total	FNA + FNA-Tg	Pathological results		Total
	Positive	Negative			Positive	Negative			Positive	Negative
Positive	106	8	114	Positive	103	11	114	Positive	120	7	127
Negative	18	77	95	Negative	21	74	95	Negative	4	78	82
Total	124	85	209	Total	124	85	209	Total	124	85	209

FNA: Fine-needle aspiration; FNA-Tg: Fine-needle aspiration thyroglobulin.

Table 4 Value of fine-needle aspiration and fine-needle aspiration thyroglobulin alone and in combination in the diagnosis of cervical lymph node metastasis in patients with thyroid carcinoma (%)

Diagnostic method	Sensitivity	Specificity	Rate of missed diagnosis	Misdiagnosis rate	Positive predictive value	Negative predictive value
FNA	85.48	90.59	14.52	9.41	92.98	81.05
FNA-Tg	83.06	87.06	16.94	12.94	90.35	77.89
FNA + FNA-Tg	96.77	91.76	3.23	8.24	94.49	95.12

FNA: Fine-needle aspiration; FNA-Tg: Fine-needle aspiration thyroglobulin.

Table 5 Univariate analysis of influence of fine-needle aspiration thyroglobulin on the single diagnosis of cervical lymph node metastasis in patients with thyroid carcinoma

Index	Correct diagnosis (n = 177)	Error diagnosis (n = 32)	t/χ2 value	P value
Age (yr)	49.3 ± 5.8	48.2±6.6	0.966	0.335
Gender, n (%)			0.140	0.708
Male	67 (37.85)	11 (34.38)
Female	110 (62.15)	21 (65.63)
Short diameter of lymph node (cm)	0.62 ± 0.11	0.60 ± 0.08	0.982	0.327
Long diameter of lymph node (cm)	1.38 ± 0.20	1.29 ± 0.23	2.288	0.023
Long diameter/short diameter, n (%)			6.965	0.008
< 2	88 (49.72)	24 (75.00)
≥ 2	89 (50.28)	8 (25.00)
Number of collected cells, n (%)			15.034	0.000
Insufficient	11 (6.21)	9 (28.13)
Sufficient	166 (93.79)	23 (71.88)
Serum TSH (ng/mL)	2.09 ± 0.39	2.31 ± 0.46	-2.854	0.005
Serum TgAb (IU/mL)	20.83 ± 5.17	22.15 ± 5.83	-1.303	0.194
Serum Tg (ng/mL)	18.94 ± 4.20	16.84 ± 4.00	2.621	0.009
Number of cervical lymph node metastases	3.41 ± 0.84	3.15 ± 0.76	1.634	0.104
Characteristics of ultrasonic signs, n (%)			4.885	0.027
Signs of metastasis	142 (80.23)	20 (62.50)
No signs of metastasis	35 (19.77)	12 (37.50)

TSH: Thyroid stimulating hormone; Tg: Thyroglobulin.

Table 6 Logistic model of the influencing factors in fine-needle aspiration thyroglobulin diagnosis of lymph node metastasis

Factors		SE	Walds	P value	OR	95%CI
Long diameter of lymph node	0.611	0.412	2.199	0.138	1.842	0.822	4.131
Long diameter/short diameter	0.741	0.338	4.806	0.041	2.098	1.082	4.069
Number of collected cells	-0.612	0.296	4.275	0.047	0.542	0.304	0.969
Serum TSH	0.285	0.217	1.725	0.216	1.330	0.869	2.035
Serum Tg	-0.442	0.186	5.647	0.025	1.556	1.081	2.240
Characteristics of ultrasonic signs	0.804	0.358	5.044	0.037	2.234	1.108	4.507
Constant term	1.309	0.684	3.662	0.091	3.702	0.969	14.149

TSH: Thyroid stimulating hormone; Tg: Thyroglobulin; OR: Odds ratio.