Myelodysplastic syndrome with monosomy 5 and/or 7 following therapy with 2-chloro-2'-deoxyadenosine.

A few cases of secondary neoplasms occurring after treatment with 2-chloro-2'-deoxyadenosine (2CdA) have been reported, mostly in patients previously exposed to other anti-cancer drugs including alkylating agents (AA). Here we report on the occurrence of a myelodysplastic syndrome (MDS) with monosomy 5 and/or 7 in two patients after 2CdA treatment, without or prior to other toxic exposure. In light of a literature review and given the involvement of chromosomes frequently abnormal in secondary leukaemias, we suggest that 2CdA may induce therapy-related MDS (t-MDS).