Secondary acute non-lymphocytic leukemia with monosomy 7 arising 9 years after acute lymphoblastic leukemia in childhood.

We report a case of pediatric acute non-lymphocytic leukemia (ANLL) with monosomy 7 occurring in a child successfully treated for acute lymphoblastic leukemia (ALL) nine years earlier. Acquired monosomy 7 is currently recognized as a distinct therapy-related cytogenetic abnormality which nonrandomly occurs as a late complication of cytotoxic therapy used in the treatment of both malignant and nonmalignant disease. Most commonly, this occurs as a disorder of bone marrow morphology and function characterized as a myelodysplastic syndrome (MDS) or ANLL. This case report emphasizes the need for continued evaluation of long-term survivors of childhood cancer to identify and minimize therapy-related side effects without compromising successful management.