[Evolutive epidemiologic profile of myelodysplastic syndromes (1959-1993). Comparative study with acute myeloid leukemia and aplastic pancytopenias].
OBJECTIVE
To compare the maximum epidemiologic data attained from myelodysplastic syndromes (MDS) with those of two main panmyelopathies, namely acute myeloblastic leukaemia (AML) and aplastic pancytopenia (AP).


METHODS
A retrospective analysis was carried out on 21,135 patients included in the Bone Marrow Study Registry of the Jiménez Díaz Foundation along 35 years (1959-1993). The data were grouped into seven five-year periods. Of these, in the first three the study was performed on bone-marrow aspirates; after 1976 the histopathological study of bone-marrow biopsies was introduced, and since 1979 the karyotype has been regularly examined. The MDS were classified in accordance with the FAB system. With these premises borne in mind, the following aspects were considered: diagnostic interpretation of MDS along the years; diagnostic incidence of MDS, AML and AP in each of the five-year periods; relative frequency of those diagnosis with respect to the total number of cases; evolutive profile of sex and age at diagnosis; quantitative significance of secondary MDS-AL and toxic AP along the years; MDS subtypes and their epidemiologic characteristics.


RESULTS
A total of 510 MDS, 610 AML and 223 AP cases were identified. With respect to the sex of the MDS patients, some changes have been seen along the years, from an M/F ratio of 1.9 to 1.0; and the mean age at diagnosis raised from 53.3 years (with only 1.7% of the cases over 65 years of age) to 71.4 years (with 76.9% of the cases over 65 years of age), all this within the 1959-1989 period. The incidence of AML and AP has remained stable for the last 20 years; on the contrary, MDS have been increasing continuously along the 35 years of the study, which poses for a higher number of new cases in every period (from 35 to 119) and also for a higher relative frequency in the registry (from 1.37% to 4.40%) within the period 1959-1989. Valuable toxic history was progressively increasing in secondary MDS-AML and progressively decreasing in AP. With respect to the FAB subtypes of MDS, and taking into account the last of the five-year periods, the most frequently diagnosed were RA and RSA followed by RAEB, CMML and RAEB-T.


CONCLUSIONS
The increment of the incidence of MDS cases correlates significantly with the increment of the patients aged over 65 years. This incidence appears to be scarcely influenced by previous mutagenic agents (radiotherapy, chemotherapy) and might be due to a better understanding of MDS.
Sánchez Fayos
J
J
Servicio de Hematología y Hemoterapia, Fundación Jiménez Díaz, Facultad de Medicina, Universidad Autónoma, Madrid.
Outeiriño Pérez
J J
JJ
Prieto
E
E
Román
A
A
Olavarría
E
E
Cabello
A
A
Soto
C
C
Calabuig
T
T
Paniagua
C
C
Sanz
B
B
D000208:Acute Disease; D017677:Age Distribution; D000368:Aged; D000753:Anemia, Refractory / Q000453:epidemiology; D005260:Female; D006801:Humans; D015994:Incidence; D007951:Leukemia, Myeloid / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D009190:Myelodysplastic Syndromes / Q000453:epidemiology*; D012189:Retrospective Studies; D017678:Sex Distribution; D013030:Spain / Q000453:epidemiology
Perfil epidemiológico evolutivo de los síndromes mielodisplásicos (1959-1993). Estudio comparativo con el de las leucemias agudas mieloides y pancitopenias aplásticas.