Table 2.

Univariate analyses results for clinicopathologic parameters associated with the cancer-specific survival and overall survival.

Covariate	Level	HR	CSS		P value	HR	OS		P value
			95% CI				95% CI
Age at diagnosis	<45	Ref.				Ref.
	45–59	1.423	0.552	3.668	0.465	1.903	1.171	3.092	0.009
	60–69	1.742	0.619	4.899	0.293	4.045	2.453	6.671	<0.001
	70–79	3.562	1.313	9.667	0.013	5.695	3.321	9.768	<0.001
	>80	8.818	2.651	29.338	<0.001	14.874	7.283	30.378	<0.001
Year of diagnosis	1973–2004	Ref.				Ref.
	2004–2015	0.548	0.28	1.073	0.079	0.873	0.61	1.25	0.459
Sex	Female	Ref.				Ref.
	Male	0.995	0.558	1.773	0.986	0.918	0.692	1.216	0.549
Race	White	Ref.				Ref.
	Black	0.891	0.398	1.997	0.779	1.529	1.071	2.183	0.019
	Other	0.249	0.034	1.814	0.17	0.764	0.424	1.378	0.371
Extent of diseases	Local disease	Ref.				Ref.
	Regional disease	1.433	0.419	4.899	0.566	1.398	0.761	2.566	0.28
	Metastatic disease	5.08	0.622	41.467	0.129	6.604	2.296	18.999	<0.001
LN status	Negative	Ref.				Ref.
	Positive	9.06	1.828	44.898	0.007	1.735	0.721	4.172	0.219
Size of tumor (cm)	0–2.9	Ref.				Ref.
	>3	5.381	1.115	25.96	0.036	1.665	0.812	3.414	0.164
Grade	Well-differentiated	Ref.				Ref.
	Moderately differentiated	0.967	0.1	9.32	0.977	0.501	0.145	1.726	0.273
	Poorly differentiated	—	—	—	0.994	1.559	0.204	11.914	0.669
	Undifferentiated	—	—	—	0.995	1.273	0.165	9.798	0.817
Radiation	No	Ref.				Ref.
	Yes	1.553	0.658	3.668	0.315	1.409	0.895	2.219	0.138
Surgery	No	Ref.				Ref.
	Yes	0.104	0.053	0.206	<0.001	0.364	0.218	0.607	<0.001
Extent of resection	No definitive treatment	Ref.				Ref.
	Parathyroidectomy	0.083	0.039	0.177	<0.001	0.299	0.175	0.511	<0.001
	En bloc radical resection	0.087	0.019	0.396	0.002	0.331	0.15	0.731	0.006
	Debulking	0.463	0.06	3.6	0.462	0.853	0.195	3.737	0.833