We demonstrated nuclear β-catenin expression and activation of the CTNNB1 gene in basal cell adenoma. Although nuclear β-catenin expression may be unable to distinguish basal cell adenoma from basal cell adenocarcinoma, it should be a helpful marker in the diagnosis of basal cell adenoma.

We investigated 115 patients with salivary gland epithelial tumors who had undergone preoperative fine needle aspiration cytology (FNAC) of salivary glands and had been diagnosed by postoperative histopathological examination. We compared the findings of preoperative FNAC with their histopathological types in salivary gland tumors, and discuss the results and problems. The diagnostic accuracy, sensitivity, and specificity of preoperative FNAC of salivary glands were 98.2%, 88.2%, and 100%, respectively. The percentage of inadequate specimens was 6.1%. The rates of agreement in the diagnosis of pleomorphic adenoma, Warthin tumor, and basal cell adenoma were 96%, 92.9%, and 55.5%, respectively. The rate of agreement of histopathological types in the malignant tumors was 30%. We realized again not only that the diagnostic accuracy of preoperative FNAC for salivary gland tumors was high, but also that it was a safe, easy-to-perform, clinically very useful diagnostic procedure. However, this study exposed several problems which are the inadequate sampling rate and the difficulty in diagnosing malignant tumors. We have been making efforts to take appropriate specimens by writing comments on the cytological report indicating a re-examination, or by the presence of the clinical laboratory technician at the FNAC procedure. We consider it necessary to adequately re-aspirate the solid portion after cyst fluid aspiration, or to re-perform FNAC at a later date, and to improve the diagnostic accuracy by further experience with more patients.

F-FDG uptake in PTC may be determined by GLUT-3 and GLUT-4 expressions and may be related to tumor size and lymph node metastasis of PTC. F-FDG uptake may reflect tumor progression of PTC.

Histiocytic sarcoma (HS) is a malignant neoplasm showing the morphological and immunophenotypic features of mature histiocytes. Reported herein is a case of HS of the parotid gland region. A 53-year-old woman noticed a swelling of the right preauricular area. Preoperative fine needle aspiration cytology showed an admixture of pleomorphic atypical cells and mature lymphocytes. She underwent total parotidectomy. Grossly, the tumor was located at the parotid gland to subcutaneous tissue, and showed infiltrative growth with massive necrosis and hemorrhage. Microscopically, the tumor was composed of marked pleomorphic cells with eosinophilic cytoplasm. Bizarre multinuclear giant cells were scattered and intermingled. Tumor cells were positive for CD68 (KP-1 and PG-M1), CD163, S-100 protein, CD1a, CD4 and CD31, but negative for CD3, CD20, CD21, CD79a, DEC205 and langerin, immunohistochemically. Monoclonal proliferation of B cells was not confirmed on polymerase chain reaction for IgH. The patient had recurrent lesions in the pelvis and stomach 5 months after parotidectomy and died of the disease 10 months after the operation.

Cystadenocarcinoma is a rare malignant tumor, with an estimated incidence of 2% of malignant salivary gland tumors. Cytological diagnosis of cystadenocarcinoma is important for differential diagnosis between benign lesions and malignant tumors with cystic growth. We report a case of cystadenocarcinoma causing difficulty in cytological diagnosis. A 23-year-old man presented with an asymptomatic mass in the left parotid gland that had been present for 2 years. The mass was elastic hard, measuring 30 x 35 mm in diameter. Preoperative fine-needle aspiration cytology (FNAC) showed a small number of tumor cell clusters in the cystic fluid. The cluster was arranged in a ball-like structure and was cohesive with overlapping. Tumor cells had a small vacuolated, soap-bubble appearance in the cytoplasm. The papillary-cystic variant of acinic cell carcinoma (ACC-PCV) was suggested from these findings on FNAC. Histologically, the tumor was not encapsulated, but formed large cystic spaces against a background of fibrous connective tissue. The tumor cells in the cystic dilated duct showed papillary structures, which were continuous with the lining cuboidal cells. There was neither a definite double-layered arrangement in cystic ducts and solid islands nor histological findings characteristic of the papillary-cystic or follicular pattern of ACC-PCV. As tumor cells with a small vacuolated, soap-bubble appearance of the cytoplasm are common findings of both cystadenocarcinoma and ACC-PCV, they are of little use for differentiation; however, they are so characteristic that the majority of benign salivary gland lesions with cystic structures can be excluded, if enough attention is paid.