Salivary duct carcinoma (SDC) is a rare primary salivary gland malignancy characterized by histological features similar to those of ductal carcinomas of the breast. It is regarded as a high-grade malignancy associated with frequent local recurrences and early distant metastases that require aggressive treatment. The typical fine needle aspiration cytology (FNAC) findings in SDC include cellular smears showing tumor cells with eccentric pleomorphic nuclei and a granular cytoplasm arranged in flat sheets or cribriform patterns against a necrotic background. However, the presence of mucin-containing cells in SDC has been rarely described. We report the FNAC findings in a patient with histologically confirmed SDC that demonstrated numerous mucin-containing cells and was subsequently misdiagnosed as a high-grade mucoepidermoid carcinoma. Here we discuss the problems involved in distinguishing SDC from high-grade mucoepidermoid carcinoma on the basis of cytologic findings alone.
Biopsy, Fine-Needle* ; Breast ; Carcinoma, Ductal ; Carcinoma, Mucoepidermoid* ; Cytoplasm ; Humans ; Mucins* ; Neoplasm Metastasis ; Recurrence ; Salivary Ducts* ; Salivary Glands

Two Domestic Korean Shorthair cats presented with dyschezia and vomiting. Computed tomography revealed a colonic mass with calcification and lymph node metastasis in case 1, and a small intestinal mass with disseminated mesenteric metastasis and calcification in case 2. Histopathology revealed intestinal adenocarcinoma with osseous metaplasia. Case 1 died two months after surgery from distant metastasis; and case 2 showed no metastasis for five months but presented with anorexia, euthanized seven months after diagnosis. Metastatic intestinal adenocarcinoma with bone formation should be considered as differential diagnosis for calcification on imaging, and lymph node metastasis at diagnosis may indicate poor prognosis.

BACKGROUND: Fine needle aspiration, which is known as the most accurate and cost-effective method for diagnosis of thyroid nodule, still may result in indeterminate cases that are pauci-cellular and show minor nuclear atypia, but most cases are associated with suspicion of papillary thyroid carcinoma (PTC). A B-type Raf kinase (BRAF) mutation was found in about half of PTCs and galectin-3 was expressed by malignant tumors, helping us to differentiate malignancies from benign lesions. METHODS: Cases studied included histologically 44 confirmed PTC cases and 18 benign cases previously diagnosed as suspicious of PTC using cytologic examination. Cases were analyzed for galectin-3 expression by immunohistochemical staining and BRAF mutation by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) with a new restriction enzyme. RESULTS: All 44 cases of PTC and 8 of 18 benign controls expressed galectin-3. BRAF mutations were found in only 9 of the 44 PTC cases. Assessment of galectin-3 expression demonstrated high sensitivity but low specificity. Evaluation of BRAF mutation revealed high specificity and low sensitivity. CONCLUSIONS: This study suggests that the combined application of these two methods for PTC of suspicious cytology is complementary.
Biopsy, Fine-Needle ; Carcinoma ; Factor IX ; Galectin 3 ; Phosphotransferases ; Sensitivity and Specificity ; Thyroid Gland ; Thyroid Neoplasms ; Thyroid Nodule