Evidence of clastogens in acute leukemia. Chromosomal abnormalities in healthy parents of congenital leukemic patients

Detection of BCR-ABL-positive cells in the colostrum of a pregnant patient with chronic myeloid leukemia

A 31-year-old pregnant woman was diagnosed with chronic-phase chronic myeloid leukemia at gestational week 16. To avoid exposure of the fetus to teratogenic agents, the patient opted for a course of careful observation only for the duration of her pregnancy. We detected 9.1% of BCR-ABL-positive cells in the patient's colostrum with fluorescence in situ hybridization.

The epidemiology of neonatal tumours. Report of an international working group

Neonatal tumours occur every 12,500-27,500 live births and comprise 2% of childhood malignancies, but there is little clarity as to their real prevalence, sites of origin and pathological nature as reported series vary. As an entity, neonatal tumours provide a unique window of opportunity to study tumours in which minimal environmental interference has occurred. The majority of tumours present with a mass at birth (e.g., teratomas, neuroblastomas, mesoblastic nephroma, fibromatosis), which are not infrequently identified on antenatal ultrasound. Histologically, teratoma and neuroblastoma remain the two main tumour types encountered with soft tissue sarcoma, renal tumours, CNS tumours and leukaemia being the next most common tumour types identified. Malignant tumours are uncommon in the neonatal period per se and benign tumours may have malignant potential. A particular problem exists in clinical classification, as histological features of malignancy do not always correlate with clinical behaviour. Benign tumours may also be life threatening because of their size and location. Other tumours may demonstrate local invasiveness, but no metastatic potential, and tumours that are clearly malignant may demonstrate unpredictable or uncertain behaviour. Screening programmes have brought more tumours to light, but do not appear to affect the overall prognosis. They may provide clues to the stage at which tumours develop in foetu. The aetiology of cancer in children is multifactorial and includes both genetic and environmental factors. The association between congenital abnormalities and tumours is well established (15% of neonatal tumours). Genetic defects are highly likely in neonatal tumours and include those with a high risk of malignancy (e.g., retinoblastoma), but also genetically determined syndromes with an increased risk of malignancy and complex genetic rearrangements. Tumours are mostly genetically related at a cellular level and factors influencing cellular maturation or apoptosis within the developing foetus may continue to operate in the neonatal period. Cytogenetics of neonatal neoplasms appear to differ from neoplasms in older children, thus possibly explaining some of the observed differences in clinical behaviour. Certain constitutional chromosome anomalies, however, specifically favour tumours occurring in the foetal and neonatal period. In support of this hypothesis, certain cytogenetic anomalies appear to be specific to neonates, and a number of examples are explored. Other environmental associations include ionizing radiation, drugs taken during pregnancy, infections, tumours in the mother and environmental exposure.

Congenital monocytic leukemia: report of a case with cutaneous involvement, and review of the literature

Congenital leukemia is a rare disease that can become manifest soon after birth. Cutaneous involvement consists of red, brown, or purple papules and nodules, and confluent areas of purpura. The diagnosis is established by the presence of leukemic cells in biopsy specimens of bone marrow and involved skin, and by immunocytochemical characterization of these cells. We report a case of congenital monocytic leukemia with a normal karyotype, whose disease underwent temporary spontaneous regression.

Translocation 4;11 acute leukemia: three case reports and review of the literature

Three children with acute leukemia and t(4;11)(q21;q23) are presented. Two of the cases showed very unusual karyotypic findings and long survival for the type of leukemia. In case B.T., the original karyotype change observed was t(4;11), with other changes (+4q-,+11q+,+6,+10) appearing during the last stages of the disease. In case R.B., the translocation was accompanied by many numerical and morphological chromosome changes, with a near-tetraploid chromosome number. In both of the above cases, remission was associated with a normal marrow karyotype. In case D.C., only the t(4;11) was observed. The number of cases with t(4;11) and acute leukemia published so far is 36, including the three cases presented by us. As this disease is usually characterized by a relatively short survival, the possible reasons for the remarkably long survival in two of our patients are discussed in relation to the rather unusual cytogenetic findings.

Abnormal chromosome in Prader-Willi syndrome

A Prader-Willi Syndrome (PWS) patient was found to have an extra satellite chromosome, smaller than the normal Chromosome 22, in 60% of her metaphases. G- and C-bandings showed that the extra chromosome did not derive from a Chromosome 15 as has been reported in some PWS patients. Because of variation in chromosomal abnormalities in the PWS patients reported, it was concluded that the chromosomal abnormalities found in them may be a secondary phenomenon rather than the cause of PWS.

Abnormal chromosomes in histocytic lymphoma

Five of six diffuse histocytic lymphoma patients had chromosomal abnormalities. Four had abnormal clones; three, a large acrocentric chromosome (LAC); and one, an abnormal large submetacentric chromosome (LSC). The LAC was a 14q+ and the LSC, a 4q+. Although no cytogenetic abnormality was found in a normal lymph node of a patient whose diseased lymph node had an LAC, abnormal chromosomes were seen in three patients with normal morphological bone marrow and in two peripheral blood specimens with a normal differential count. Since staging is important in aiding the clinician to select the type of treatment in this disease, it is recommended that cytogenetic studies in all biopsied tissues should be done as part of an overall diagnostic procedure in patients suspected of this disease.

Congenital acute lymphoblastic leukemia with chromosomal abnormalities including a translocation (1;4;22)

Cytogenetic studies in a patient with inborn ALL demonstrated identical and complex abnormalities in all the cells, indicating a monoclonal origin. These abnormalities included, among others, a translocation (1;4;22).

Significance of a (4;11) translocation in acute lymphoblastic leukemia

This report describes a case of null cell congenital acute lymphoblastic leukemia associated with a (4;11) translocation. This chromosome abnormality is associated with acute lymphoblastic leukemia and probably more specifically with congenital acute lymphoblastic leukemia. A review of the literature is presented.