Diagnostic accuracy of technetium-99m-pertechnetate scintigraphy with lemon juice stimulation to evaluate Warthin's tumor.

UNLABELLED

This study investigated the diagnostic accuracy of 99mTc-pertechnetate scintigraphy with lemon juice stimulation for evaluating parotid gland Warthin's tumor.

METHODS

Technetium-99m-pertechnetate scintigraphy with intraoral lemon juice stimulation was used to evaluate a total of 68 parotid gland lesions clinically suspected of being Warthin's tumor in 62 patients. Twenty-three of the 68 lesions were subsequently histologically confirmed to be Warthin's tumor, whereas the remaining 45 lesions were histologically diagnosed as being other lesions.

RESULTS

Technetium-99m-pertechnetate scintigraphy with lemon juice stimulation correctly diagnosed 18 of 23 Warthin's tumors as being Warthin's tumor but was unable to diagnose the other five Warthin's tumors. Further, scintigraphy correctly diagnosed 41 of 45 non-Warthin's tumors as being non-Warthin's tumor but misdiagnosed other four non-Warthin's tumors as Warthin's tumor. Thus, the sensitivity of scintigraphy for diagnosing Warthin's tumor was found to be 78%, its specificity 91% and its accuracy 87%. On the basis of prestimulation images alone, however, the sensitivity was estimated to be 65%, its specificity 93% and its accuracy 84%.

CONCLUSION

For evaluating Warthin's tumor, the sensitivity of 99mTc-pertechnetate scintigraphy was relatively low, although the specificity was sufficiently high. Lemon juice stimulation improved the sensitivity markedly but decreased the specificity slightly. Thus, 99mTc-pertechnetate scintigraphy with lemon juice stimulation should be carefully performed for diagnosis of Warthin's tumor.