Takaaki Ogawa

FDG PET as a procedure for detecting simultaneous tumours in head and neck cancer patients.

AimThe presence of simultaneous primary tumours in other regions affects the prognosis and management decisions of head and neck cancer patients. Therefore, early detection of these tumours is necessary. Recent improvements in positron emission tomography (PET) have made it possible to examine the patients whole body. The present study was undertaken to evaluate the clinical contribution of whole-body PET using fluorodeoxyglucose (FDG) for head and neck cancer patients. MethodsFifty-three consecutive patients with previously untreated head and neck cancer were examined. Whole-body FDG PET imaging was performed at 1 h after injection of 18F-FDG. A 3-D acquisition was undertaken and iterative reconstruction was performed. The final diagnosis of simultaneous primary tumour was established by histological findings or clinical follow-up. ResultsOf 53 patients, six (11%) had evidence of simultaneous primary tumour. In five of these six patients, simultaneous primary tumours (two gastric cancer; one colon cancer; one pancreatic cancer; one thyroid cancer) were found by FDG PET. One more patient was found to have prostate cancer on the basis of blood test but this was not detected by FDG PET. In none of the remaining 47 patients, were additional simultaneous primary tumours found by FDG PET or any of the other routine examinations or during follow-up. ConclusionsThe results of this study show a high rate of simultaneous primary tumour in patients with primary head and neck cancer. FDG PET appears to be a promising imaging modality for the detection of simultaneous tumours in head and neck cancer patients.

Multivariate analysis of factors influencing oral mucositis in allogeneic hematopoietic stem cell transplantation

Little information is available regarding the effect of oral intervention on the outcome of hematopoietic stem cell transplantation (HSCT). We retrospectively analyzed the incidence of oral mucositis after allogeneic HSCT with or without oral intervention among 96 consecutive patients in our hospital between January 1988 and March 2006. We combined two oral intervention strategies: cryotherapy and oral health care. The former was applied beginning in 2003 for patients being treated with melphalan, and the latter, which was the study’s main strategy, was applied to all HSCT recipients beginning in 2004. Oral mucositis was evaluated according to NCI CTCAE v3.0. The incidence of oral mucositis was 30.9% (17/55) in reduced-intensity stem cell transplantation (RIST), which was significantly lower than the 90.2% (37/41) in conventional stem cell transplantation (CST; P < 0.001). Among these 96 patients, severe oral mucositis was observed in 19 (46.3%) CST cases and in 6 (10.9%) RIST cases (P < 0.001). The occurrence of oral mucositis apparently decreased after oral health care instructions were given. Multiple logistic analysis revealed that the conditioning regimen and oral health care were independent risk factors for the incidence of oral mucositis. The cryotherapy did not exert enough potency to prevent oral mucositis in patients who had undergone CST or RIST. We concluded that oral health care improved tissue damage due to an overall upgrade in oral hygiene during chemotherapy.

D‑Tagatose inhibits the growth and biofilm formation of Streptococcus mutans

Dental caries is an important global health concern and Streptococcus mutans has been established as a major cariogenic bacterial species. Reports indicate that a rare sugar, D-tagatose, is not easily catabolized by pathogenic bacteria. In the present study, the inhibitory effects of D-tagatose on the growth and biofilm formation of S. mutans GS-5 were examined. Monitoring S. mutans growth over a 24 h period revealed that D-tagatose prolonged the lag phase without interfering with the final cell yield. This growth retardation was also observed in the presence of 1% sucrose, although it was abolished by the addition of D-fructose. S. mutans biofilm formation was significantly inhibited by growth in sucrose media supplemented with 1 and 4% D-tagatose compared with that in a culture containing sucrose alone, while S. mutans formed granular biofilms in the presence of this rare sugar. The inhibitory effect of D-tagatose on S. mutans biofilm formation was significantly more evident than that of xylitol. Growth in sucrose media supplemented with D-tagatose significantly decreased the expression of glucosyltransferase, exo-β-fructosidase and D-fructose-specific phosphotransferase genes but not the expression of fructosyltransferase compared with the culture containing sucrose only. The activity of cell-associated glucosyltransferase in S. mutans was inhibited by 4% D-tagatose. These results indicate that D-tagatose reduces water-insoluble glucan production from sucrose by inhibiting glucosyltransferase activities, which limits access to the free D-fructose released during this process and retards the growth of S. mutans. Therefore, foods and oral care products containing D-tagatose are anticipated to reduce the risk of caries by inhibiting S. mutans biofilm formation.

Bone carrier technique with disposable syringe

rtificial bone is increasingly used for dental implants in proedures such as bone grafts and the augmentation of the floor f the maxillary sinus. Most artificial bone is dry, granular owder which, when we take it to the site of the bony defect, s easily spilled into non-sterile areas, or those contaminated ith oral bacteria.1–3 It is also difficult to measure the volume eeded, so we have developed a simple technique to transport t with a disposable syringe.

Rhabdomyosarcoma of the Mandible

Abstract This report is of an embryonal rhabdomyosarcoma presenting in the mandible of a 12-year-old boy. The tumour exhibited rapid growth and resistance to chemotherapy. The clinical findings, diagnostic course, and treatment are described in detail.