Identification of Warthin's tumor with technetium-99m pertechnetate

Warthin Tumor Incidentally Detected on PET/CT Showing Both 68Ga-DOTANOC and 18F-FDG Uptake

ABSTRACT

A patient with moderately differentiated pancreatic neuroendocrine tumor with synchronous multifocal liver metastases was referred for further staging with PET/CT. The examinations were performed on 2 consecutive days and showed mild 68Ga-DOTANOC and intense 18F-FDG uptake in an incidental right parotid nodule. Differential diagnoses include primary or metastatic neuroendocrine tumor, malignant or benign primary parotid tumor, and intraparotid lymph node. Histology revealed characteristics of a Warthin tumor. While focal FDG uptake in Warthin tumor is frequently described, the somatostatin expression was rarely reported. This clinical case describes 68Ga-DOTANOC and 18F-FDG uptake in a parotid Warthin tumor histologically confirmed.

Identification of Warthin tumor: magnetic resonance imaging versus salivary scintigraphy with technetium-99m pertechnetate

OBJECTIVE

The aim of this study was to evaluate the accuracy of technetium-99m (Tc-99m) pertechnetate scintigraphy and magnetic resonance (MR) imaging in the diagnosis of Warthin tumor.

METHODS

Sixteen cases of Warthin tumor and 17 cases of non-Warthin tumor were examined by Tc-99m pertechnetate scintigraphy with lemon juice stimulation and MR imaging, including T1-weighted, T2-weighted, short inversion time inversion recovery, diffusion-weighted, and contrast-enhanced dynamic images. We used the receiver operating characteristic (ROC) curve to evaluate diagnostic accuracy.

RESULTS

The mean area under the ROC curves of MR imaging in the diagnosis of Warthin tumor (0.97) was higher than that of Tc-99m pertechnetate scintigraphy (0.88).

CONCLUSION

Magnetic resonance imaging is more useful in the evaluation of Warthin tumor than Tc-99m pertechnetate scintigraphy.

Four cases of Warthin's tumor of the parotid gland detected with FDG PET

In the cancer screening with FDG PET for 1,872 medical health club members, high FDG accumulation in the parotid gland was found in four males (age, 57-70 years). Warthin's tumor was confirmed by surgical pathology. The exact mechanism of high FDG accumulation in Warthin's tumor is not yet known. This tumor may be found incidentally during FDG PET studies. When high FDG accumulation is found in the parotid gland, integrated consideration of the results of the physical examination, medical history and 99mTc-pertechnetate scintigraphy makes it possible to differentiate Warthin's tumor from other lesions.

Radiological findings of adenolymphoma (Warthin's tumor)

The radiological findings of adenolymphomas (Warthin's tumor) treated in six hospitals between 1985 and 1994 were compared with the operative and histological findings and the usefulness of the radiological examinations was evaluated. The total number of patients was 72. The mean age was 61.8 years; 61 were males and 11 were females. All tumors developed in the parotid gland. Tc-99m-pertechnetate salivary gland scanning was performed in 13 patients and an increased uptake of the isotope was observed in only six patients. Even if Tc-99m-pertechnetate salivary gland scanning does not reveal intense accumulation, this tumor should not be ruled out. By computed tomography (CT), ultrasonography (US), and magnetic resonance imaging (MRI), the margin of all tumors was evident; however, the contents of the tumor varied. The contents and multiplicity of the tumors were well demonstrated by MRI, which was found to be the most accurate imaging modality.

Interpretation of scintigraphy of papillary cystadenoma lymphomatosum (Warthin's tumor) on the basis of histopathologic findings

OBJECTIVES

The accumulation of 99mTc-pertechnetate in Warthin's tumor was estimated scintigraphically and histopathologically to determine the role of the epithelial component in scintigraphy.

STUDY DESIGN

Six cases underwent histopathologic examination and scintigraphic evaluation with 99mTc-pertechnetate. Histopathologically the tumors were classified into types according to the epithelial component and cystic space and compared with scintigraphic results evaluated by dynamic radioactive index and wash-out image.

RESULTS

Histopathologic and scintigraphic observations showed an adequate correlation. Cases with a large epithelial component and poor cystic space showed a large radioactive index of dynamic scintigraphy and hot accumulation of wash-out image.

CONCLUSION

The scintigraphic results were chiefly due to the epithelial component, but the influence of the cystic space could not be disregarded.

Salivary scintigraphy with vitamin C stimulation: an aid in differentiating unilateral parotitis from Warthin's tumor

Of the nine patients included in this study, five with proven unilateral parotitis initially had diffuse high uptake of 99mTc-pertechnetate in the affected glands with adequate washout following vitamin C stimulation. Of four patients with proven Warthin's tumor, two had focal high uptake in the parotid masses and two had diffuse high uptake on baseline images. All tumors were clearly delineated after stimulation. 99mTc-pertechnetate salivary scintigraphy with vitamin C stimulation may provide a useful tool in differentiating unilateral parotitis from Warthin's tumor.