Table 2.

Sensitivity of neck ultrasonography and [¹⁸F]DOPA in the detection of regional and locoregional lymph node metastasis in all studied patients in relation to the results of histology

	DOPA PET/CT	Neck ultrasonography	Histology
Central regions (level VI)
Metastatic levels (n)	8	3	15
Sensitivity	53% (95% CI 35–53)*	20% (95% CI 7–20)
Specificity	100% (95% CI 84–100)	100% (95% CI 88–100)
PPV	100% (95% CI 65–100)	100% (95% CI 33–100)
NPV	71% (95% CI 59–71)*	59% (95% CI 52–59)
Accuracy	78% (95% CI 61–78)	63% (95% CI 50–63)
P value vs. histology	0.001*	0.092
Lateral regions (levels I, II, III, IV, V)
Metastatic levels (n)	19	10	26
Sensitivity	73% (95% CI 60–73)*	39% (95% CI 26–39)
Specificity	100% (95% CI 99–100)	100% (95% CI 99–100)
PPV	100% (95% CI 82–100)	100% (95% CI 68–100)
NPV	97% (95% CI 96–97)*	94% (95% CI 93–94)
Accuracy	98% (95% CI 95–98)*	94% (95% CI 92–94)
P value vs. histology	<0.001	<0.001
All regions
Metastatic levels (n)	27	13	41
Sensitivity	66% (95% CI 57–66)*	32% (95% CI 23–32)
Specificity	100% (95% CI 99–100)	100% (95% CI 99–100)
PPV	100% (95% CI 86–100)	100% (95% CI 73–100)
NPV	95% (95% CI 94–95)*	91% (95% CI 90–91)
Accuracy	96% (95% CI 93–96)*	91% (95% CI 89–91)
P value vs. histology	<0.001	<0.001
Patient-based analysis
Patients with LN metastases (n)	12	8	19
Sensitivity	63% (95% CI 48–63)*	42% (95% CI 27–42)
Specificity	100% (95% CI 78–100)	100% (95% CI 78–100)
PPV	100% (95% CI 76–100)	100% (95% CI 65–100)
NPV	65% (95% CI 50–65)	54% (95% CI 43–54)
Accuracy	78% (95% CI 60–78)	66% (95% CI 48–66)
P value vs. histology	<0.001	0.01
Patients with N0 (n)	20	24	13
Patients with N1a (n)	1	1	4
Patients with N1b (n)	11	7	15
Patients with N1a+b (n)	7	2	11
Patients with bilateral LN metastasis (n)	6	1	8

LN lymph node, PPV positive predictive value, NPV negative predictive value

*P < 0.05 vs. ultrasonography