[Identification of differentiated dysplasia improves prediction of oral leukoplakia at increased risk of malignant progression]. / Onderkenning van gedifferentieerde dysplasie voor het voorspellen van de kans op maligne ontaarding van orale leukoplakie.

Oral leukoplakia is the most common potentially malignant disorder of the oral mucosa with a rate of malignant transformation into oral squamous cell carcinoma of 1-2% annually. The presence or absence of dysplasia as defined by the WHO is an important histological marker for malignant transformation risk assessment, but is not sufficiently accurate for patient stratification. We investigated whether identifying differentiated dysplasia contributes to oral leukoplakia malignant transformation risk assessment. We investigated whether classic or differentiated dysplasia were present in 84 oral leukoplakias. In 25 of these patients a squamous cell carcinoma developed during follow-up. Risk of malignant progression of oral leukoplakia increased from 3.3 (HR, p = 0.002) when only classic dysplasia was considered to 7.4 (HR, p = 0.001) when both classic and differentiated dysplasia were combined. This study demonstrates that identifying differentiated dysplasia as a separate type of dysplasia is important for the prognosis and stratification of patients with oral leukoplakia.

Treatment results of CO2 laser vaporisation in a cohort of 35 patients with oral leukoplakia.

OBJECTIVES: The aim of the present study was to evaluate the treatment results of CO2 laser vaporisation in a well-defined cohort of patients with oral leukoplakia (OL). MATERIAL AND METHODS: The group consisted of 35 patients. Before treatment, a clinical photograph and an incisional biopsy were performed in all cases. Also posttreatment results were documented with clinical photographs. The assessment of the treatment results was performed by an independent clinician who had not performed the treatment. The mean follow-up period was 61.9 months (range 12-179 months). RESULTS: In 14/35 patients, there was a recurrence between 1 and 43 months (mean 18.7 months), the annual recurrence rate being approximately 8%. In three of these patients, malignant transformation occurred at a later stage. In two other patients, a malignancy occurred without a prior recurrence. In altogether 5 of 35 patients, malignant transformation occurred in a mean period of 54 months, the annual malignant transformation rate being approximately 3%. CONCLUSIONS: The results in the present study are worse than those reported in the literature, perhaps owing to the use of different diagnostic criteria for OL, differences in the employed laser technique and assessment of possible recurrences by an independent clinician.

DNA ploidy measurement in oral leukoplakia: different results between flow and image cytometry.

The estimated prevalence of oral leukoplakia is worldwide approximately 2%, with an annual malignant transformation rate of approximately 1%. The aim of the present study was to evaluate the possible contribution of ploidy measurement to the prediction of the clinical course, in a well defined cohort of patients with oral leukoplakia. Ploidy was measured by both flow cytometry (FCM-DNA) and image cytometry (ICM-DNA) and we focussed on the comparison of the two different techniques to determine ploidy. A total of 41 patients have been included, with a mean age of 59 years (range 36-78 years). With FCM-DNA, three lesions were aneuploid, with ICM-DNA, 19 lesions were aneuploid. DNA ploidy was compared with clinicopathological and patients parameters. There were no statistically significant differences between DNA ploidy and any patient factor with both FCM-DNA and ICM-DNA. Using FCM-DNA, DNA aneuploid lesions showed statistically significant more dysplasia (p=0.04) than diploid lesions. Furthermore, DNA aneuploid lesions were more frequently encountered at high-risk locations (p=0.03) as being determined with FCM-DNA. These relations were not found when DNA ploidy was determined with ICM-DNA.

Quality of life and disability after ilio-inguinal lymphadenectomy.

AIM: To examine and report the quality of life together with the level of disability of cancer patients who underwent therapeutic ilio-inguinal lymphadenectomy. MATERIALS AND METHODS: The complete files of 62 patients who underwent 66 procedures between January 1990 and November 2006 were obtained and analysed retrospectively. Data concerning postoperative complications, presence and extent of lymphoedema, physical symptoms, duration of disability, daily life and social activities were collected through a specific questionnaire and reviewed. RESULTS: Early postoperative complications occurred in 36% of cases. Sixty-five percent of patients developed some degree of postoperative lymphoedema. Twenty patients suffered at least one episode of erysipelas. Median postoperative disability was 4 months (range 1.5 to 24 months). Among the active population, 8 patients (18%) never returned to work. Postoperative quality of life was good or very good for most patients, with acceptable limitation in daily activities. CONCLUSION: Ilio-inguinal lymphadenectomy is the only radical procedure able to provide long-term tumour control and maintain a good to very good quality of life, thus providing a real possibility of returning to work.

Electrothermal debonding of ceramic brackets. An in vitro study.

Two different kinds of devices for electrothermal debonding of ceramic brackets are evaluated. Thirty human premolars were bonded with two types of ceramic brackets. Both devices were tested for electrothermal removal of the two bracket types. The pulpal wall temperature increase during electrothermal debonding was recorded in vitro under various circumstances. After debonding, the fracture site was located. The data were compared to the temperature rise after simulated exposure of the teeth to warm beverages. Irreversible pulp damage due to electrothermal debonding of ceramic brackets with both instruments is not to be expected because the obtained results stayed below established primate threshold temperatures and significantly below that of the stimulated control groups. A significant difference was noted when air cooling was initiated during electrothermal debonding. Fracture site location was significantly different in the two ceramic bracket types after electrothermal debonding.