Epidemiology of myelodysplastic syndromes in a French general hospital of the Basque country.

Epidemiologic studies concerning myelodysplastic syndromes (MDS) are rare. The estimated incidence varies between 1 and 12.6/100,000/year. The aim of this work was to compare our own experience with these data. Our general hospital represents a structure with 1197 beds which serves a population of 290,000 individuals (French Basques). Most of the inhabitants live in a rural environnement. Twenty percent of the population are aged over 65. During a 4-year period (1993-1996), 90 new cases of MDS were diagnosed on bone marrow studies in our laboratory. Among FAB subtypes refractory anemia (RA) represented 27 cases (31%), RA with ring sideroblasts (RARS): 21 (23%), RA with excess of blasts (RAEB) and in transformation (RAEB-t): 22 (24%), chronic myelomonocytic leukemia (CMML): 10 (11%). Ten cases were unclassifiable (11%). Therapy-related MDS were seen in 8 patients. The sex ratio was 1 and the mean age of the patients was 74.3 (range: 23-96), 37% of them being 80 years or older. The calculated incidence was 7.7/100,000/year for the entire cohort and 31.4/100,000/year for people over 65.