Hepatocellular carcinoma metastatic to the mandible.

We describe the case of a 55-year-old man with known multifocal hepatocellular carcinoma (HCC) who presented with a painful mandibular mass. Fine-needle aspiration cytology of the mass revealed the presence of bile canaliculi and bile formation, an extremely rare finding. Findings on immunoperoxidase staining of the aspirate were consistent with an HCC. Since the patient was known to have multiorgan metastatic disease, he was administered palliative radiation therapy to the mandibular metastasis for pain control, which was achieved. One year after presentation, the patient died as a result of disease progression. HCC rarely metastasizes to the mandible, as only about 70 such cases have been reported in the literature. We discuss the histopathologic appearance of HCC metastatic to the mandible, the radiologic findings, and the established treatment modalities.

Synchronous ipsilateral Warthin tumor encased by a separate mucoepidermoid carcinoma of the parotid gland: a case report and review of the literature.

Fine-needle aspiration (FNA) is a cost effective and low morbidity procedure in the initial assessment of salivary gland tumors. However, cytological assessment of ipsilateral synchronous tumors (which make up less than 0.3% of all salivary gland neoplasms) may pose diagnostic challenges. Therefore, a wholesome approach, including FNA with clinical and radiological correlation, is of utmost importance. Here, we report a unique case of Warthin tumor encased by a separate high-grade mucoepidermoid carcinoma that was first diagnosed on FNA. Another striking feature seen was the presence of chronic sialadenitis in the surrounding nonneoplastic salivary gland. The presence of two different neoplasms in the background of chronic sialadenitis raises the question of a possible causal relationship. Traditionally, there has been diagnostic difficulty when dealing with synchronous tumors of the salivary gland and the background of chronic sialadenitis may further complicate the diagnosis. FNA is very helpful and can give important cues to the diagnosis.

"Benign," metastasizing adenomyoepithelioma of the breast: a report of 2 cases.

Adenomyoepitheliomas of the breast are rare tumors composed of a proliferation of 2 cell populations. For the most part, they are considered to be benign, but they locally recur. Those neoplasms that metastasize are deemed to have come from a histologically malignant primary tumor. Herein, we describe 2 cases of metastases of histologically "benign" adenomyoepitheliomas of the breast to the lung. In both cases, the primary neoplasms and the metastases did not show histologic features of malignancy. These unique cases represent another example of neoplasms that can metastasize in the absence of histologic features that would suggest malignant behavior. Establishing the diagnosis, determining optimal therapy, and predicting outcome are problematic because of the rarity of this entity. Perhaps, classification of adenomyoepitheliomas should be changed to recognize those neoplasms with malignant behavior.

An important role for protein kinase C-delta in human keratinocyte migration on dermal collagen.

Migration of human keratinocytes plays a critical role in the re-epithelialization of human skin wounds, the process by which the wound bed is resurfaced and closed by keratinocytes as it forms a new epidermis. While the importance of ECM components and serum factors in the regulation of keratinocytes motility is well established, the intracellular signaling mechanisms remain fragmentary. In this study, we investigated the role of protein kinase Cdelta (PKCdelta) signaling in the promotion of human keratinocyte migration by a collagen matrix and bovine pituitary extract. We found that pharmacological inhibition of the PKCdelta pathway completely blocks migration. Using a lentivirus-based vector system, which offers more than 90% gene transduction efficiency to human keratinocytes, we show that the kinase-defective mutant of PKCdelta (K376R) dramatically inhibits human keratinocyte migration. Furthermore, PKCdelta is activated in migrating human keratinocytes. These observations indicate for the first time that the PKCdelta pathway plays an important role in the control of human keratinocyte migration.