Childhood cancer in New Zealand 1990 to 1993.

An epidemiological study of childhood cancer in New Zealand identified 409 children aged 0 to 14 years with malignant neoplasms newly diagnosed between 1990 and 1993 inclusive. The original microscopic material on which the diagnoses were based was reviewed in 398 cases and the neoplasms were allocated into the 12 major groupings and 48 further subcategories of the International Classification of Childhood Cancer (ICCC). The pathology reviewers agreed with group and subcategory classification of the confirmed cancers in all but one case of acute leukemia and three cancers of the central nervous system. Changes were also made in the FAB classification of three cases of acute non-lymphocytic leukemia and in the further subcategorisation of three Hodgkin's lymphomas and ten astrocytomas. The results show a high level of diagnostic accuracy for confirmed childhood neoplasms in that time period. Nine of 15 cases of malignant melanoma notified to the study were not confirmed for various reasons, which included a change in the pathological diagnosis in four cases. Compared with Victoria (Australia), New Zealand has a high incidence rate of lymphomas in boys and an unusual female preponderance of Wilms' tumor cases.

Childhood acute lymphoblastic leukaemia: outcomes of 54 consecutive patients treated in Auckland 1985-1991.

AIMS: To report the survival and event-free survival of children with acute lymphoblastic leukaemia treated in Auckland between 1985-1991, using an international protocol, ANZCCSG ALL Study V. METHODS: The data were collected prospectively as part of the study. The analysis was carried out using standard survival methods. RESULTS: At a median follow up of 7.5 years, the overall survival is 75% and event-free survival 60%. CONCLUSIONS: For an unselected series, these outcomes are comparable to overseas series. The survival for children diagnosed in the 1990's is likely to be similar.

Good prognosis of cellular mesoblastic nephroma with hyperdiploidy and relaxation of imprinting of the maternal IGF2 gene.

A large congenital mesoblastic nephroma (CMN) of combined classical and and cellular histological structure was removed from a 1-month-old female infant. The tumor extended extrarenally and may have been incompletely excised. Tumor tissue showed a mosaic hyperdiploidy with 54 chromosomes in the hyperdiploid line. No other antitumor therapy was given and there has been no recurrence after 4 years. Genomic imprinting normally prevents transcription of the maternal gene for insulin-like growth factor 2 (IGF2). Relaxation of IGF2 imprinting leading to abnormal transcription of the maternal gene is found in a majority of Wilms' tumors and in other malignant neoplasms. The biallelic transcription of IGF2 demonstrated in the CMN from this case is consistent with abnormal transcription of the maternal allele. Relaxation of imprinting of the maternal IGF2 gene or abnormal expression of the gene through other mechanisms may have a role in the genesis of CMN or the cellular subtype.

Constitutional relaxation of insulin-like growth factor II gene imprinting associated with Wilms' tumour and gigantism.

We have examined the imprinting of the insulin-like growth factor II gene (IGF2) in ten normal kidney samples from children with renal embryonal neoplasms. In kidney samples from nine children with normal growth profiles, IGF2 mRNA was transcribed monoallelically, consistent with normal imprinting of the gene. But in one child who had generalized somatic overgrowth, IGF2 was transcribed from both alleles in her kidney, peripheral blood leukocytes and Wilms' tumour. These findings suggest that a defect in genomic imprinting can occur constitutionally, leading to growth abnormalities and predisposition to Wilms' tumour.

Childhood cancer among the Polynesian population.

From June 1981 through June 1989, 95 Polynesian children were seen for initial care of malignancy at the Princess Mary Hospital for Children (PMHC). The incidence of malignancy in the Polynesian populations served, the histology of the malignancies, and the outcome of therapy were reviewed and compared with 185 non-Polynesian (non-P) patients seen during the same period. Incidence figures for Polynesians and non-P were similar, but histologic patterns differed, showing an increased occurrence of leukemia, particularly nonlymphoblastic leukemia, an increased occurrence of bone tumors, and a decreased incidence of central nervous system tumors for Polynesians. Survival for Polynesian children with acute lymphoblastic leukemia was worse than for non-P. Survival in all other disease categories was similar.