Spontaneous Slowing and Regressing of Tumor Growth in Childhood/Adolescent Papillary Thyroid Carcinomas Suggested by the Postoperative Thyroglobulin-Doubling Time

Table 2

Comparison of clinical and biochemical features among the patients with and without RAI administration.

Group	A	B	B-1	B-2
	RAI not administered	RAI administered	≤13 mCi	≥30 mCi
	()	()	()	()
Age, yrs	17 (7–18)	16 (14–18)	16 (14–17)	17 (16–18)
Males/females	1/8	1/4	0/3	1/1
Tumor size, mm	23 (13–46)	25 (15–45)	25 (18–45)	30 (15–45)
Total dose of RAI, mCi	0	13 (6–113)	13 (6–13)	78 (43–113)
Number of Tg measurements	6.5 (4–12)	6 (4–7)	4 (4–7)	6.5 (6-7)
Follow-up period, yrs	8.0 (4.4–13.3)	12.2 (3.5–15.8)	12.2 (3.5–15.8)	11.1 (8.7–13.4)
Tg-DT, yrs	7.1 (−4.5–147.4)	9.1 (6.9–11.5)	9.1 (6.9–11.5)	9.0 (7.5–11)
1/Tg-DT	0.12 (−0.29–0.51)	0.14 (−0.29–0.51)	0.11 (0.087–0.15)	0.11 (0.091–0.13)
hTV-DT, yrs	0.5 (0.25–0.6)	0.5 (0.44–0.51)	0.48 (0.44–0.5)	0.51 (0.51)
1/hTV-DT	1.99 (1.68–4.01)	2 (1.68–4.01)	2.09 (1.99–2.29)	1.95 (1.95)

RAI: radioactive iodine. Values are median (ranges) and numbers of cases. Tg: thyroglobulin, Tg-DT: thyroglobulin-doubling time, and hTV-DT: hypothetical tumor volume-doubling time. Five of the 14 patients underwent RAI administration: ≤13 mCi in 3 patients (B-1) and ≥30 mCi in 2 patients (B-2). Note that 1/Tg-DT was significantly smaller than 1/hTV-DT even in group A (). Both the 1/Tg-DTs and 1/hTV-DTs were not significantly different in each group.