Secondary acute myeloid leukaemia with monosomy 7 in identical adult twins.

We report the development of secondary acute myeloid leukaemia (AML) with monosomy 7 in identical twins, both at the age of 52 years. In the first twin, induction therapy resulted in complete remission (CR). At relapse 9 months later monosomy 7 was found. The patient died of sepsis 11 months after diagnosis. The other twin presented with leucopenia and thrombocytopenia and refractory anaemia (RA) was diagnosed. During follow-up, fluorescence in situ hybridization analysis demonstrated a monosomy 7 in 11% of the cells. Twenty-eight months following diagnosis the patient progressed to RA with excess blasts in transformation and induction chemotherapy was initiated without achieving CR. Three months later an allogeneic stem cell transplantation from a niece was performed, resulting in CR of the secondary AML.