Chromosome pattern and survival in acute non-lymphocytic leukaemia in relation to age and occupational exposure to potential mutagenic/carcinogenic agents.

The bone marrow karyotype was investigated in 98 patients with acute non-lymphocytic leukaemia (ANLL). The patients were divided into two groups according to age. (1) 47 patients were 20-54 (median 40) years old. 21 had a history of occupational exposure to chemical solvents, insecticides, or petrol products, and 26 were considered occupationally not having been exposed to such agents. In 4 exposed patients (19%) all bone marrow cells had clonal chromosomal aberrations (designated AA), while also 4 of the non-exposed patients (15%) were AA. Thus in young ANLL patients, there was no significant association between occupational exposure to potential mutagenic/carcinogenic agents and the AA constitution of the leukaemic cells. (2) 51 patients were 55 years of age or older (median 65 years). 16 were exposed and 8 of these (50%) had the AA constitution. 35 patients were non-exposed and only 4 (11%) were AA. It is known from previous studies that the survival of ANLL patients with AA is extraordinarily short. Accordingly the overrepresentation of AA in exposed patients 55 years or older, was associated with a shorter survival than that of the non-exposed elderly patients. The results suggest that etiologic factors may influence the clinical course of ANLL, especially in elderly patients.