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

Secondary myelodysplasia with monosomy 7 arising after treatment for acute lymphoblastic leukemia in childhood

Monosomy 7 is recognized as a characteristic, clonal abnormality associated with acquired myelodysplasia (MDS) or acute myeloid leukemia (AML). It can occur as a late complication of cytotoxic therapy and is usually associated with exposure to alkylating agents or radiation therapy. We report two patients with therapy-related myelodysplasia (t-MDS) associated with monosomy 7 occurring in children after completion of therapy for acute lymphoblastic leukemia (ALL). Both children were noted to have t-MDS with monosomy 7 at the time of cessation of chemotherapy. Neither child had received an alkylating agent or radiation therapy during treatment. One child had a unique dicentric marker chromosome that was shown by fluorescent in situ hybridization to be derived from chromosome 7. This report emphasizes the need to identify and minimize therapy-related side effects without compromising cure rates.

Unilateral retinoblastoma with acquired monosomy 7 and secondary acute myelomonocytic leukemia

Patients with a nongenetic form of retinoblastoma are not particularly at high risk of developing second malignant neoplasms. We report here a case of treatment-related leukemia (secondary leukemia) with acquired monosomy 7, in a child with unilateral retinoblastoma.

Involvement of 11p15 and 3q21q26 in therapy-related myeloid leukemia (t-ML) in children. Case reports and review of the literature

The cytogenetic findings of therapy-related myeloid leukemia (t-ML) in three children are presented. These included one male patient with acute lymphoblastic leukemia (ALL) who underwent bone marrow transplantation and developed therapy-related myeloproliferative disease (t-MPD) in the female-donor hematopoietic cells 2.5 years after receiving radiation and epipodophyllotoxin therapy for ALL testicular relapse. Bone marrow leukemic cell karyotype revealed 46,XX,add (11)(p15) and a normal female karyotype in the peripheral blood lymphocytes. The other two children, one with ALL and one with ganglioneuroblastoma, developed fatal t-MPD and therapy-related acute myeloblastic leukemia (t-AML) preceded by myelodysplastic syndrome (t-MDS), respectively, 5 years after diagnosis, following administration of alkylating agents and irradiation. Monosomy 7 was present in both, and was combined with inv(3)(q21q26) in the second patient. Our review of the cytogenetic findings in 91 previously reported pediatric patients with t-ML suggested that the involvement of 11p15 and 3q21-->23, 3q24-q26 with or without a combination of translocation 11q23 and -7/7q-, respectively, are nonrandom aberrations of t-ML in children. Comparison of the chromosomal changes in t-ML between the pediatric and an adult series revealed some differences which may result from differences in treatment modalities and which, in addition, may indicate a possible role of genetic and/or age-dependent factors in the pathogenesis of therapy-related leukemogenesis in children.