TABLE 1:

Characteristics of primary cancers

Patient (No.)	Tumor Location	Stage	MR Imaging Time Points	Percentage Measurement Error, %
1	Base of tongue	T4	2	23*, 19
2	Pyriform sinus	T4	3	18, 20, 16
3	Base of tongue	T3	5	5, 7, 12, 17, 2
4	Base of tongue	T4	1	0
5	Tonsil	T4	3	1, 2, 10
6	Tonsil	T3	4	1, 3, 22†, 29†
7	Base of tongue	T3	0‡	None
8	Tonsil	T4	3	6, 15, 53†
9	Base of tongue	T2	4	13, 8, 37*, 11
10	Base of tongue	T3	2	16, 11
11	Base of tongue	T2	3	1, 3, 12
12	Base of tongue	T2	3§	29*, 22*, 2
13	Base of tongue	T3	3	4, 8, 19
14	Base of tongue	T4	3	9, 3, 22†
15	Pyriform sinus	T4	3	7, 2, 23†
16	Tonsil	T2	3	0, 13, 26†
17	Base of tongue	T2	3	4, 4, 2

^*Percentage measurement error was greater than 20% because of difficulty in differentiating the neoplasm from adjacent lymphoid tissue at the base of the tongue.

^†Percentage measurement error was greater than 20% because of a small absolute differences in the volume measurements of small lesions.

^‡The primary tumor was too large to measure.

^§T1-weighted images were used because of artifact on T2-weighted images.