Role of human papillomavirus and tumor suppressor genes in oral cancer.

The incidence of oral cancer remains high and is associated with many deaths in both Western and Asian countries. Several risk factors for the development of oral cancer are now well known, including smoking, drinking and consumption of smokeless tobacco products. Genetic predisposition to oral cancer has been found in certain cases, but its components are not yet entirely clear. In accordance with the multi-step theory of carcinogenesis, the natural history of oral cancer seems to gradually evolve through transitional precursor lesions from normal epithelium to a full-blown metastatic phenotype. A number of genomic lesions accompany this transformation and a wealth of related results has appeared in recent literature and is being summarized here. Furthermore, several key genes have been implicated, especially well-known tumor suppressors such as the cyclin-dependent kinase inhibitors, TP53 and RB1 and oncogenes such as the cyclin family, epidermal growth factor receptor and RAS. Viral infections, particularly oncogenic human papillomavirus subtypes and Epstein-Barr virus, can have a tumorigenic effect on oral epithelia and their role is discussed, along with potential therapeutic interventions. A brief explanatory theoretical model of oral carcinogenesis is provided and potential avenues for further research are highlighted.

Intrathecal morphine in two patients undergoing deep hypothermic circulatory arrest during aortic surgery -A case report-.

We retrospectively report the first use of intrathecal morphine prior to incision in two male patients undergoing a complex aortic reconstruction, who required complete circulatory arrest under deep hypothermia for intraoperative and postoperative pain control. We administered intrathecal morphine to two male patients undergoing circulatory arrest and deep hypothermia. Patients were fully heparinized prior to cardiopulmonary bypass. Deep hypothermic circulatory arrest was performed by cooling the patients to 18℃. Following the surgery, the neurologic status was monitored. The management of postoperative pain is a quality standard in health care. During the first 24 hours after surgery, we observed excellent analgesia without the associated side effects, thus, reducing the time required for pain control by the nursing staff. A successful analgetic strategy not only enhances the patient satisfaction, but may improve the postoperative outcome. However, complications, such as increased risk of epidural hematoma formation, are of special concern in cardiac surgery.