[Rapid setting calcium phosphate cement for craniomaxillofacial surgery. 6 years experience]. / Schnell abbindender Kalziumphosphatzement für die kraniomaxillofaziale Chirurgie. Erfahrungen über sechs Jahre.

BACKGROUND: Long-term results using hydroxyapatite cement (Bone Source) for the reconstruction of the facial skeleton and the forehead are reported. MATERIAL AND METHODS: The cement consists of 73% tetracalcium phosphate and 27% dicalcium phosphate. Using 0.25 M phosphoric acid instead of water, the primary setting time can be shortened from 20 to 5 min in an isothermic reaction. Twenty-two patients suffering from consequences of trauma, tumor-like lesions, or neoplasm as well as dysmorphia were treated. RESULTS: Following implantation, the healing process proceeded in most cases without complications. Due to hematoma and seroma as well as infection, two implants were lost. Follow-up examinations could be performed in 19 of the 22 patients on a average 40 months after operation. Most patients had good clinical long-term results. X-ray-analysis showed some discrete resorption of the implants in six patients. The further course must be decided based on clinical relevance. DISCUSSION: The hydroxyapatite cement used in this study evidenced good intraoperative handling, an excellent histologically proved biocompatibility, and good long-term stability in normal body fluid. Up to now we have limited its use to non-load-bearing applications in craniofacial surgery.

[Oral adenoid squemous carcinoma. Tumor markers and prognosis]. / Orales adenoid-squamöses Karzinom. Tumormarker und Prognose.

CASE REPORT: A 58-year-old female patient presented with an exophytic adenoid squamous cell carcinoma on the right alveolar process of the lower jaw. Histological and immunohistochemical differential diagnosis and cellular background of the unfavorable prognosis are described. The patient was treated with curative intent by radical tumor resection including partial mandibulectomy, extensive conservative/radical neck dissection, and postoperative radiation. The adenoid squamous cell carcinoma was classified as pT4, pN0, cM0, R0. During radiation, regional lymph node metastases and distant metastases developed. The patient died of distant metastases 7 months after the initial diagnosis. HISTOPATHOLOGIC FINDINGS: Tumor cells of adenoid squamous cell carcinoma express epithelial intermediate filament cytokeratin, epithelial membrane antigen (EMA), and epithelial basal membrane protein laminin-5 (Ln-5). Glandular differentiation can be excluded by the absence of epithelial mucins (Alcian blue, mucicarmine). Differentiation from angiosarcoma can be performed using endothelial differential markers CD31, CD34, and factor VIII-associated antigen (FVIII-ass. AG). Both entities are characterized by high proliferation and Ki-67 index of 20%. beta-catenin (cell-cell adhesive protein) loses its primary membrane-bound localization and can explain the histologic pattern of acantholysis. Ln-5 (guide rail of invasion) is massively expressed in adenoid squamous cell carcinoma cells and may be responsible for rapid progression. CONCLUSIONS: Pseudopapillary proliferation, cellular atypia, vascular-like cavities, expression of cytokeratin, EMA, and Ln-5 are common features of oral adenoid squamous cell carcinoma and angiosarcoma. Diagnosis is determined by the absence of endothelial differential markers CD31, CD34, and FVIII-ass. AG. Modulation of the beta-catenin pattern (transcription factor of Ln-5) and massive expression of invasion factor Ln-5 are suggested as cell biological reasons for rapid progression of adenoid squamous cell carcinoma.