Table 2.

Recurrence according to subclassification of invasion in solitary papillary thyroid carcinoma

Classification	Recurrence, no. (%)	HR	95 % CI	p value
I
E0	12 (6.1)	1 (ref)		0.015
E1	38 (14.7)	2.444	1.277–4.676	0.007
E2	11 (12.1)	2.076	0.916–4.786	0.080
II (current T stage)
E0	12 (6.1)	1 (ref)
E1 + E2	49 (14.0)	2.350	1.250–4.419	0.006
III
E0 + E1	50 (11.0)	1 (ref)
E2	11 (12.1)	1.144	0.595–2.198	0.686

E0 confinment to thyroid parenchyma, E1 extension to perithyroid soft tissue, E2 extension to sternothyroid muscle