Sialyl Lewis^a (CA19-9 antigen), a high molecular weight glycoprotein, was originally described as a gastrointestinal tract- and pancreas-specific tumor marker. However, the diagnostic usefulness of sialyl Lewis^a expression in salivary gland tumors is not well established. Therefore, we examined the diagnostic significance of sialyl Lewis^a (CA19-9 antigen) expression in salivary gland tumors. Surgical materials, consisting of 30 benign (20 pleomorphic adenomas, 5 basal cell adenomas, 5 myoepitheliomas) and 30 malignant (13 mucoepidermoid carcinomas, 13 adenoid cystic carcinomas, 4 salivary duct carcinomas) salivary gland tumors, were subjected to examination in this study. To measure expression of sialyl Lewis^a in these tumors, a streptavidin-biotinyl immunoperoxidase method was performed using anti-human CA19-9 antibody. There was a tendency for malignant salivary gland tumors, to express sialyl Lewis^a more intensely than benign tumor (P<0.05). As the expression pattern is generally characterized by localization in relatively highly differentiated malignant cells such as mucous-producing cells and atypical luminal duct cells, poorly differentiated tumors such as adenoid cystic carcinoma solid type and salivary duct carcinoma are consistently shown to express sialyl Lewis^a less frequently. Five (tubular type 2 and cribriform type 3) of 13 (38.5%) cases were stroma positive for sialyl Lewis^a in the adenoid cystic carcinoma. Sialyl Lewis^a expression appears to be increased by the malignant transformation of salivary gland tumors. The clinical applications of sialyl Lewis^a in patients with salivary gland tumors may be worth examining more closely in the future.

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The expression of GnT-V has been shown to correlate with tumor invasion, metastasis and poor prognosis in several tumors. We examined the expression of glycosyltransferases, Nacetylglucosaminyltransferase V (GnT-V) in 40 cases of human tongue squamous cell carcinoma (SCC) and its relationship to clinicopathological characteristics. Twenty-six of the 40 cases of SCC showed positive expression of GnT-V in cytoplasm of tumor cells by imunohistochemistry, whereas none of the 4 premalignant lesions showed positive signals for GnT-V. High expression of GnT-V was positively correlated with big tumor size (T category), infiltrative invasion pattern (vs. expansive), high histological malignancy (differentiation), and cervical lymph node metastasis. Furthermore, in the early clinical stage of SCC, the subsequent metastatic rate was significantly higher in SCCs that were GnT-V positive than in SCCs that were GnT-V negaive. All SCC cases examined showed increased GnT-V mRNA levels in comparison to normal tongue tissues by real-time PCR. Contrastively, GnT-V expression was not enhanced in premalignant lesions. These findings suggest that GnT-V expression is closely correlated with tongue SCC progression and the malignant phenotype.

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The present study was designed to investigate histochemically the biodegradation processes of chitin and chitosan implanted in rat alveolar bone. Lysozyme was immunohistochemically detected using postembedding immunogold labeling. The degradation process was ultrastructurally observed using the lectin-colloidal gold technique with electron microscopy. Three groups of chitin were specially prepared according to their degree of deacetylation: 100% deacetylated chitin (DDAC 100); 50% (DDAC 50); and 0% (DDAC 0). The present immunohistochemical study indicated that lysozyme expression was not detected in the DDAC 100 group. Furthermore, electron microscopy clearly demonstrated that the contour of implanted chitosan changed over time, and that chitosan-like fragments were present in the phagosomes in the DDAC 50 and 100 groups. These findings strongly suggest that phagocytes, such as multinuclear cells, are easily supplied in bone tissue and that the phagocytosis is more effective than enzymatic digestion for chitin and chitosan biodegradation in bone tissue. DDAC 100 should be a suitable biomaterial for bone surgery and bone regeneration therapy.

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We report a rare case of desmoplastic fibroma that originated in the maxillary alveolus of an 84-year-old woman. CT demonstrated a large osteolytic intraosseous mass extending to the maxilla and nasal cavity. The curettaged mass, which was 3×3×5 cm in size and had an oval shape, consisted of spindle cells separated by abundant collagen fibers. Immunohistochemical analysis revealed that the spindle cells had a fibroblastic origin. These features may be confused with well-differentiated fibrosarcoma, another type of intraosseeous fibrous lesion. However, the cells were not atypic and were negative for Ki-67. Thus, the present case was diagnosed as a desmoplastic fibroma. Desmoplastic fibroma originating in the maxillary alveolus is extremely rare (3 reported cases, including the present case). The present case is characterized by the age of the patient, 84 years, which is higher than in previous reports.

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A 57-year-old man was referred to our hospital because of a lump of his lateral neck region. Aspiration and intraoperative biopsies were performed to confirm the pathological diagnosis. The tumor showed a neoplastic epithelium arranged in a ductal or follicular pattern with papillary proliferation, and tumor cells were immunohistochemically positive for thyroglobulin. The pathological diagnosis was papillary thyroid carcinoma metastasis to a lymph node in the lateral neck region. Metastases were also observed in other lymph nodes in the submandibular region, and multiple metastatic foci were later found in the lungs and brain. Heavy ion radiotherapy was performed to extend the patient's life.

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