Risk Factor Analysis for Central Lymph Node Metastasis in Papillary Thyroid Microcarcinoma

Figures & data

Table 1 Detailed Information of All PTMC Patients

	Overall
n	687
CLNM, n (%)
Yes	121 (17.6)
No	566 (82.4)
Sex, n (%)
Male	164 (23.9)
Female	523 (76.1)
Irregular shape, n (%)
Yes	276 (40.2)
No	411 (59.8)
Unclear margin, n (%)
Yes	385 (56.0)
No	302 (44.0)
Microcalcification, n (%)
Yes	351 (51.1)
No	336 (48.9)
Suspected CLNM, n (%)
Present	41 (6.0)
Absent	646 (94.0)
Age, n (%)
<55 years	528 (76.9)
≥55 years	159 (23.1)
Multifocal, n (%)
Present	84 (12.2)
Absent	603 (87.8)
Size, n (%)
≥5mm	503 (73.2)
< 5mm	184 (26.8)
CLT, n (%)
Present	109 (15.9)
Absent	578 (84.1)
Tumor extension, n (%)
Confined into the capsule	535 (77.9)
Extension to the capsule	116 (16.9)
Extension to adjacent structures	36 (5.2)
Surgical resection, n (%)
Total thyroidectomy with bilateral CLND	215 (31.3)
Lobectomy plus isthmusectomy with ipsilateral CLND	472 (68.7)
No. of the harvested lymph nodes (mean (SD))	3.91 (1.32)

Abbreviations: CLNM, central lymph node metastasis; CLT, chronic lymphatic thyroiditis; CLND, central lymph node dissection; PTMC, papillary thyroid microcarcinoma.

Table 2 Comparison of Information Between PTMC Patients with NCLNM and PTMC with CLNM

Factors	NCLNM	CLNM	P value
n	566 (82.4)	121 (17.6)
Sex, n (%)
Male	130 (23.0)	34 (28.1)	0.278
Female	436 (77.0)	87 (71.9)
Irregular shape, n (%)
Yes	220 (38.9)	56 (46.3)	0.159
No	346 (61.1)	65 (53.7)
Unclear margin, n (%)
Yes	312 (55.1)	73 (60.3)	0.344
No	254 (44.9)	48 (39.7)
Microcalcification, n (%)
Yes	271 (47.9)	80 (66.1)	<0.001
No	295 (52.1)	41 (33.9)
Suspected CLNM, n (%)
Present	31 (5.5)	10 (8.3)	0.335
Absent	535 (94.5)	111 (91.7)
Age, n (%)
<55 years	422 (74.6)	106 (87.6)	0.003
≥55 years	144 (25.4)	15 (12.4)
Multifocal, n (%)
Present	70 (12.4)	14 (11.6)	0.928
Absent	496 (87.6)	107 (88.4)
CLT, n (%)
Present	97 (17.1)	12 (9.9)	0.066
Absent	469 (82.9)	109 (90.1)
Tumor extension, n (%)
Confined into the capsule	455 (80.4)	80 (66.1)	0.001
Extension to the capsule	87 (15.4)	29 (24.0)
Extension to adjacent structures	24 (4.2)	12 (9.9)
Size, n (%)
≥5mm	410 (72.4)	93 (76.9)	0.377
< 5mm	156 (27.6)	28 (23.1)
Surgical resection, n (%)
Total thyroidectomy with bilateral CLND	181 (32.0)	34 (28.1)	0.467
Lobectomy plus isthmusectomy with ipsilateral CLND	385 (68.0)	87 (71.9)

Abbreviations: CLNM, central lymph node metastasis; NCLNM, non central lymph node metastasis; CLT, chronic lymphatic thyroiditis, PTMC, papillary thyroid microcarcinoma.

Table 3 Univariate Analysis of Variables Related to Central Lymph Node Metastasis (CLMN)

Characteristics	OR	95% CI	P value
Sex
Male	1.311	0.842–2.04	0.2304
Female	Reference
Age
<55 years	2.411	1.36–4.276	0.0026
≥55 years	Reference
Size
≥5mm	1.264	0.797–2.004	0.3196
< 5mm	Reference
Irregular shape
Yes	1.355	0.913–2.012	0.132
No	Reference
Unclear margin
Yes	1.238	0.83–1.847	0.2954
No	Reference
Microcalcification
Yes	2.124	1.408–3.204	0.0003
No	Reference
Suspected CLNM
Present	1.555	0.741–3.264	0.2434
Absent	Reference
Multifocal
Present	0.837	0.487–1.437	0.5176
Absent	Reference
CLT
Present	0.532	0.282–1.004	0.0516
Absent	Reference
Tumor extension
Confined into the capsule	Reference
Extension to the capsule	1.896	1.17–3.072	0.0094
Extension to adjacent structures	2.844	1.367–5.916	0.0052
Surgical resection
Total thyroidectomy with bilateral CLND	0.831	0.539–1.283	0.4039
Lobectomy plus isthmusectomy with ipsilateral CLND	Reference

Abbreviations: CLNM, central lymph node metastasis; CLT, chronic lymphatic thyroiditis; CLND, central lymph node dissection; PTMC, papillary thyroid microcarcinoma; OR, odds ratio; CI, confidence Interval.

Table 4 Multivariate Analysis of Variables Related to Central Lymph Node Metastasis (CLMN)

	OR	95% CI	P value
Microcalcification
Yes	2.066	1.361–3.135	<0.001
No	Reference
Tumor extension
Confined into the capsule	Reference
Extension to the capsule	1.772	1.083–2.897	0.023
Extension to adjacent structures	2.872	1.355–6.089	0.006
Age
<55 years	2.341	1.309–4.187	0.004
≥55 years	Reference

Abbreviations: OR, odds ratio; CI, confidence Interval.