Oral squamous cell carcinoma: an analysis of 1,564 cases showing advances in early detection.

The present study aimed to detect possible differences in the data of oral squamous cell carcinomas (OSCC) cases diagnosed in a Dental School in São Paulo city over the last 40 years. The records of patients diagnosed as having OSCC between the years 1960 and 2008 were retrieved. The whole period was divided into four time periods. A total of 1,564 cases were reviewed. The variables analyzed were: sex, age, race, anatomical site, lesion duration, and lesion size. The chi-square test was used for statistical analysis. Overall, males were more affected than females (3:1), but when comparing the first and last time periods, the ratio decreased significantly (5.8:1 to 2.8:1). A significant increase in the rate of OSCC in patients over 80 years was observed in the last time periods. The gingiva was the most affected site, but the frequency of lower lip involvement increased in the last time period. Regarding lesion size and duration of symptoms at the time of diagnosis, there was a significant difference between the first and last time periods. Smaller lesions were found and the time of lesion development was shorter in the last few years of the study. These findings support the optimistic view that, in recent years, earlier diagnosis has resulted from early oral cancer detection in São Paulo city.

Altered cytokeratin expression in actinic cheilitis.

BACKGROUND: Actinic cheilitis (AC) is a widely recognized precancerous lesion of the lip. Varying degrees of epithelial dysplasia may be present. However, no studies have correlated epithelial changes with cytokeratin expression that might reflect the disordered maturation that is probably occurring. METHODS: Thirty-four cases diagnosed as AC were classified according to dysplasia degree, and submitted to immunohistochemical staining for the detection of cytokeratins (CKs) 7, 8, 13, 14, 16 and 19. Normal mucosa adjacent to the lesions was also evaluated. RESULTS: The results obtained showed that CK10 immunostained only superficial keratinized epithelial layers in 11 cases, and also intermediate spinous layers in 18 cases. Cytokeratin 14 was expressed in all epithelial layers of 31 cases, in two cases its expression was in the basal and intermediate layers, and one case was negative. Cytokeratin 13 immunostained 26 cases and was negative in eight cases. In these eight cases, CK13 was apparently replaced by CK16. Cytokeratin 16, besides these eight cases, was also expressed in the spinous intermediate layers of a further eight cases. The remaining CKs tested were all negative. No relation between the degree of dysplasia and the CK expression was noted. CONCLUSIONS: Cytokeratin expression in AC is different from that of normal oral mucosa, and is not related to the degree of dysplasia.