TABLE 1.

RS Differences With and Without RAI Therapy for Studied Cancer Types as Stratified by Recurrence Risk Categories

		Overall (n)								Follow-up > 10 y (n)
TNM stage	Cancer type	RAI	No RAI	RAI?to?no RAI absolute difference (%) at 3 y	z	P	RAI–to–no RAI absolute difference (%) at 5 y	z	P	RAI	No RAI	RAI–to–no RAI absolute difference (%) at 10 y	z	P
T1bN0M0–T2N0M0	PTC	12,341	14,773	0.09	3.165	0.002	0.09	2.186	0.029	3,700	2,202	0.09	1.280	0.201
	PTC aggr.	145	117	0.43	0.928	0.353	0.43	0.552	0.581	31	13	−0.37	0.112	0.911
	FTC	979	888	0.73	2.696	0.007	0.73	1.765	0.078	425	318	0.73	1.677	0.094
	FTC min. inv.	511	584	0.10	1.229	0.219	0.19	1.176	0.240	220	130	2.02	1.916	0.055
T3N0M0 or minimal ETE	PTC	6,494	3,598	0.32	−0.891	0.373	0.32	−0.571	0.568	2,461	1,164	1.25	2.009	0.045
	PTC aggr.	178	74	0.37	−0.248	0.804	0.37	−0.173	0.863	72	25	0.29	−0.027	0.978
	FTC	770	528	1.09	0.226	0.821	0.64	0.184	0.854	285	167	3.68	1.547	0.122
	FTC min. inv.	338	291	0.30	0.206	0.836	0.83	1.128	0.259	134	78	1.21	0.036	0.971
T1N1M0–T3N1M0	PTC	17,627	6,241	1.10	3.776	0.000	1.57	2.948	0.003	5,655	1,700	1.95	2.184	0.029
	PTC aggr.	495	137	2.78	1.889	0.059	2.36	1.154	0.248	128	40	1.99	0.708	0.479
	FTC	64	25	17.38	2.673	0.008	12.68	1.635	0.102	17	9	16.45	1.858	0.063
	FTC min. inv.	11	6	0.00	0.000	1.000	0.00	0.000	1.000	3	3	0.00	0.000	1.000
T3N1–T4N1, or M1, or gross ETE	PTC	9,449	3,187	10.26	24.026	0.000	11.25	22.720	0.000	3,197	903	11.89	19.720	0.000
	PTC aggr.	445	131	17.29	5.564	0.000	18.90	5.209	0.000	130	37	16.89	4.278	0.000
	FTC	220	173	34.06	7.874	0.000	39.61	8.148	0.000	44	18	30.91	7.191	0.000
	FTC min. inv.	22	9	10.71	1.554	0.120	8.25	1.030	0.303	5	1	−22.08	0.202	0.840

RS = relative survival; ETE = extrathyroidal extension; PTC aggr. = aggressive variants of PTC; FTC min. inv. = minimally invasive FTC.
Differences in RS were tested using z-test particularly suited for comparing RS.