Table 1.

Comparison of clinicopathological characteristics between patients with low-risk PTMC without LNM who underwent lobectomy with prophylactic CCND (N=4,927) (Group I) and patients with low-risk PTMC except clinically apparent LNM who underwent total thyroidectomy with MRND (N=421) (Group II)

	Group I	Group II	P-value
Age (years), mean±SD	46.1±8.7	47.5±1.7	0.001
Male/female ratio	901/4,026 (18.2%/81.8%)	117/304 (27.7%/72.3%)	<0.001
Tumor size (cm), mean±SD	0.5±0.2	0.7±0.2	0.001
Multifocality	496 (10.1%)	197 (46.7%)	<0.001
Microscopic ETE	1,326 (26.8%)	243 (57.7%)	<0.001
Central node metastasis	1,024 (20.7%)	308 (73.1%)	<0.001
Retrieval LN	4.8±3.7	8.5±6.6	<0.001
Central LNR	0.11±0.03	0.53±0.22	0.013
Lateral node metastasis	–	421 (100%)	–
Retrieval LN	–	30.1±13.8	–
LNR	–	0.23±0.15	–
Total LNR	0.11±0.03	0.30±0.12	0.031
Pathologic type			0.017
Papillary	4,927 (100%)	421 (100%)
Classic	4,752 (96.5%)	401 (95.2%)
Follicular variant	165 (3.3%)	17 (4.1%)
Diffuse sclerosing	10 (0.2%)	3 (0.7%)
T stage			<0.001
T1	3,602 (73.1%)	179 (70.3%)
T2	2 (0.02%)	0
T3	1,323 (26.7%)	242 (37%)
T4	0	0
N stage			<0.001
N0	3,903 (79.2%)	0
N1a	1,024 (20.7%)	0
N1b	0	421 (100%)
TNM staging			<0.001
Stage I	4,114 (83.5%)	226 (53.6%)
Stage II	3 (0.001%)	0
Stage III	810 (16.4%)	12 (2.8%)
Stage IV	0	183 (43.4%)
Distant metastasis	0	2 (0.4%)	0.006
Recurrence	48 (0.9%)	22 (5.2%)	<0.001
Disease-specific mortality rate	0	2 (0.4%)	0.006

Abbreviations: CCND, central compartment neck node dissection; ETE, extrathyroidal extension; LN, lymph node; LNM, lymph node metastasis; LNR, lymph node ratio; MRND, modified radical neck dissection; PTMC, papillary thyroid microcarcinoma; TNM, tumor node metastasis.