Table 1.

Relationship between non-predominant micropapillary pattern and clinic-pathological variables before and after PSM.

Variables	Before matching (n = 866)		P value	After matching (n = 460)		P value
	M+ not pren = 344	M−n = 522		M+ not pren = 230	M−n = 230
Age
≤60	173	283		116	127
>60	171	239	0.258	114	103	0.304
Sex
Male	151	225		105	87
Female	193	297	0.818	125	143	0.089
Smoking status
Yes	148	220		100	94
No	196	302	0.798	130	136	0.571
Tumor laterality
Left	148	173		84	90
Right	196	349	0.003	146	140	0.564
Papillary subtype
P−	276	385		183	172
P+ not pre	37	98		33	41
P pre	31	39	0.006	14	17	0.473
Solid subtype
S−	261	339		187	180
S+ not pre	38	67		28	29
S pre	23	72	0.001	15	21	0.562
Spread through air spaces
Yes	97	102		53	60
No	247	420	0.003	177	170	0.448
Lymphovascular invasion
Yes	55	86		39	28
No	289	436	0.849	191	202	0.146
CEA (ug/L)
≤5	223	406		171	177
>5	114	105	<0.001	59	53	0.515
Tumor size (cm)
≤1	23	64		16	17
>1 to ≤2	148	244		99	93
>2 to ≤3	173	214	0.004	115	120	0.850
Lymph node metastasis
Yes	128	106		62	59
No	216	416	<0.001	168	171	0.751
Pathological stage
I	216	415		168	171
II	22	29		13	10
IIIA	106	78	<0.001	49	49	0.811

M−, micropapillary <5%; M+ not pre, micropapillary ≥5%, but not predominant; M pre, micropapillary predominant;

S−, solid <5%; S+ not pre, solid ≥5%, but not predominant; S pre, solid predominant;

P−, papillary <5%; P+ not pre, papillary ≥5%, but not predominant; P pre, papillary predominant;

PSM, propensity score matching.