Chromosome aberrations following cytotoxic therapy in patients in complete remission from lymphoma.

The frequency of chromosome aberrations in the peripheral blood of patients successfully treated for Hodgkin's disease (HD) and non-Hodgkin's lymphoma is compared with that seen in age-matched haematologically normal subjects. Findings are considered in relation to risk factors associated with the development of secondary myelodysplastic syndrome (MDS) or acute myeloid leukaemia (AML). Overall aberration frequencies were not significantly increased in patients compared with normal subjects. However, there were differences in aberration type. The frequency of exchanges was significantly higher among patients (P less than 0.01) and the frequency of gaps lower (P less than 0.0005). The mean frequency of exchanges was also greater in patients receiving multiple compared to single courses of therapy (P less than 0.0005) and in patients receiving radiotherapy or combined modality therapy compared to chemotherapy alone (P less than 0.005 and P less than 0.0005). Four patients had aberration frequencies greater than 2 SD above the patient mean. One of these was also found to have a mutation of the ras oncogene. None of the patients has yet developed secondary MDS/AML.