Radioiodine Thyroid Remnant Ablation after Recombinant Human Thyrotropin or Thyroid Hormone Withdrawal in Patients with High-Risk Differentiated Thyroid Cancer

Table 1

(a) Selected patient characteristics by treatment group. (b) Basis for AJCC/UICC staging in the study cohort.

(a)  

Variable	rhTSH group (n = 18)	THW group (n = 27)	P
Age at DTC diagnosis
Mean ± SD years	41 ± 16	51 ± 14	0.03
≥45 years old, % (n)	78% (14)	37% (10)	0.01
Female, % (n)	83% (15)	78% (21)	0.30
Histological classification, % (n)
Papillary, classical variant	78% (14)	82% (22)
Papillary, follicular variant	6% (1)	11% (3)	0.08
Follicular	16% (3)	7% (2)
T classification^a, % (n)
T3	72% (13)	74% (20)
T4a	22% (4)	19% (5)	0.53
T4b	6% (1)	7% (2)
N classification^a, % (n)
N0/Nx	67% (12)	66% (16)
N1a	27% (5)	22% (6)	0.08
N1b	6% (1)	18% (5)
Patients with vascular invasion, % (n)	22% (4)	26% (7)	0.33
AJCC/UICC stage^ab, % (n)
I	22% (4)	63% (17)	0.01
II	0% (0)	0% (0)
III	50% (9)	33% (9)
IVa	11% (2)	4% (1)
IVb	17% (3)	0% (0)
IVc	0% (0)	0% (0)
Lymph node dissection, n (%)	78% (14)	81% (22)	0.49

AJCC: American Joint Committee on Cancer; DTC: differentiated thyroid carcinoma; rhTSH: recombinant human thyroid-stimulating hormone; SD: standard deviation; UICC: Union Internationale Contre le Cancer; THW: thyroid hormone withdrawal or withholding.
^aAccording to AJCC/UICC classification, 6th edition of 2002 [32]; all patients had M0 staging confirmed by the postablation whole-body scan.
^bSee Table 1(b) for explanation of the basis of staging in this cohort.

(b)  

TN status^a, n	AJCC/UICC stage^a	rhTSH group (n = 18)	THW group (n = 27)
Age < 45 years
T3N0	I	2	3
T3Nx	I	0	2
T3N1a	I	2	2
T3N1b	I	0	4
T4aN0	I	0	4
T4bN1a	I	0	1
T4bN1b	I	0	1
Age ≥ 45 years
T3N0	III	7	4
T3Nx	III	0	2
T3N1a	III	2	3
T4aN0	IVa	0	1
T4bN0	IVb	3	0
T4bN1a	IVa	1	0
T4bN1b	IVa	1	0

AJCC: American Joint Committee on Cancer; DTC: differentiated thyroid carcinoma; rhTSH: recombinant human thyroid-stimulating hormone; UICC: Union Internationale Contre le Cancer; THW: thyroid hormone withdrawal or withholding.
^aAccording to AJCC/UICC classification, 6th edition of 2002 [32]; all patients had M0 staging confirmed by the postablation whole-body scan.