“…Our patient was among those reported by Rosner and G runw ald [1], They were usually among the longest survivors, and in most cases, MM appeared to be in remission when acute leukemia was discovered [1][2][3][4][5][6], The mean duration from the diagnosis of MM to the development of acute leukemia in the reported series ranged from 39 months in the Mayo series [3] to 63 months in the group treat ed by melphalan alone and 56 months with the group treated by melphalan plus irradiation in a series of patients reported by acute leukemia group B (ALGB) [1]. The mean latent period in our four patients was 72 months and similar fin dings of a relatively longer interval have also been experienced by others [2,4,5], This complication has been generally attributed to the oncogenic potential of alkylating agents and irradiation. However, in 13 instances [10][11][12][13][14], the two diseases occurred simultaneously, without previous chemotherapy.…”