Author(s): Delisle MJ, Schvartz C, Theobald S, Maes B
Since 1966, data from 1536 patients with a thyroid carcinoma, living in the French region Champagne-Ardenne, a geographical area with 1,350,000 inhabitants were registered. The creation of a multidisciplinary group and the involvement of the general practitioners, allowed us to reach an exhaustive and continued registration process for the French administrative area of Marne and Ardennes (855,000 inhibitants, 627 patients). The sex-ratio F/M was 3.8 and the median ages were respectively equal to 46 [10-93] and 52 [13-82] in females and males. In the age groups 10-14 and 15-19, 3 cases and 13 cases were respectively registered. An history of external irradiation was noted in 2.9% of the patients. The study of the incidence around the Chooz nuclear plant (Ardennes) did not show an increase of the risk. For the French administrative area Marne and Ardennes, for the period 1975-1979, the incidence rates, standardized on the European population, were equal to 1.75/100,000 in males (SD = 0.15) and 6.38/100,000 (SD = 0.29) in females. These values among the highest from the data published by the other European registries should be explained by a more intensive diagnosis procedure and an improvement in the accuracy of histological diagnosis. An increase of the incidence rate was observed between the periods 1975-1983 and 1984-1992 from 1.04 to 2.05/100,000 and 4.99 to 6.39/100,000 in males and females respectively. This was associated with changes in clinical and histological features and an improvement in survival curves. For patients under the age of 19, we have compared both periods before and after the accident of Chernobyl. The incidence rates increased from 0.13 to 0.45/100,000 and 0.49 to 1.81/100,000 in the age groups 10-14 and 15-19 respectively. This change was at the order of magnitude to this observed in our adults population. We did not found the histological aggressiveness which characterized the Chernobyl-induced thyroid cancer in children. The knowledge of the significant prognostic factors determined by multifactorial analyses is a major foundation of our therapeutic strategy.