Table 2. Reliability of predicting lymph node metastasis on CT at each cut-off vale.

Cut-off value	CT	pN(+)	pN(-)	Total	Sensitivity	Specificity
8 mm	≧8mm	7	0	7
	<8mm	26	69	95	0.21	1
3 mm	≧3mm	27	35	62
	<3mm	6	34	40	0.82	0.49