The CancerWeb Report, What's New In Cancer: November, 1996
Childhood Cancer

• Length at birth an indicator of risk for Wilms' tumor? - Researchers at the University of Bergen examined the relationship between length at birth and incidence of the kidney cancer Wilms' tumor in 1,489,297 children born in Norway between 1967 and 1992. Their results, published in the October, 1996 issue of the British Journal of Cancer, listed 119 cases aged 0-14 years, among whom a high length at birth was associated with a greater risk for the tumor, with a risk ratio of 1.8 for a length over 53 cm (20.9 in) compared with one of less than 49 cm (19.3 in). A low Apgar score, a measure of overall infant health in terms of respiratory effort, heart rate, muscle tone, reflex activity, and color, also suggested a higher risk (risk ratio of 2.2 for a score less than 8 versus one greater than 9). However the relationships only held for those children less than 2 years of age, in whom the disease may have a different cause than in older children. (Heuch, Br J Cancer 74:1148, 1996)

  Editor's Comment: - As with many other examples of increased risk for various kinds of cancer associated with particular factors, the findings need to be kept in perspective. The annual incidence of Wilms' tumor in the US is around 6 per million children. The incidence in the Norwegian study is similar, just over 3 per million. A doubling of the risk still does not constitute an epidemic, and is no reason for parents to panic if their newborn infants are above the normal length. In fact, with epidemiological studies of rare diseases it is frequently impossible to be sure the results do not reflect chance alone even if large numbers are involved, as in the present study.

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• Predicting relapse of childhood acute myeloid leukemia - Most children with acute myeloid leukemia will go into remission when treated. Since a large proportion of the children relapse subsequently, there must still be residual leukemic cells in the body. It may be that there are too few of these leukemic cells to detect by light microscopy. An article by a group of pediatric oncologists from throughout the US, describes the use of a semi-automated staining and sorting process, called multidimensional flow cytometry, to discriminate between the specific antigens on large numbers of normal and leukemic cells. This article appeared in the October 16, 1996 issue of the Journal of the National Cancer Institute. The test makes it possible to detect between one in a hundred and one in a thousand malignant cells among the total population of proliferating cells. Leukemic cells were detected by this technique in more than half of the children in "complete remission." Thirteen of 14 patients who did not receive bone marrow transplants and were positive for leukemic cells by the test, relapsed. This test may be a good indicator of potential relapse, and therefore, of which patients may benefit from more intensive therapy. (Sievers, J Natl Cancer Inst 88:1483, 1996)

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• Avoiding the long-term side effects of radiation in patients with germ-cell tumors of the brain - Germ-cell tumors of the brain, which mainly occur in children, are rare and fall into two groups, germinomas which are extremely responsive to radiotherapy, and non-germinomas which are somewhat less sensitive. Unlike other kinds of brain cancers, these tumors are relatively responsive to chemotherapy. Unfortunately, while radiotherapy may cure the tumor, exposing normal brain tissue to radiation can produce a variety of long-term side-effects that include stunted growth, an adverse impact on intellectual development, hormone abnormalities, hearing loss, and second tumors. An international group of doctors studying these cancers reported a potential treatment scheme that avoided the use of radiation, in the November, 1996 issue of the Journal of Clinical Oncology. They used four cycles of chemotherapy with carboplatin, etoposide and bleomycin. Two further cycles of the same drugs were given to those who had a complete response, while the rest of the patients received the two cycles intensified with cyclophosphamide and second surgery as needed. Complete remissions occurred in 57% of the patients after receiving four cycles of chemotherapy, this figure reached 78% after further treatments. For germinomas, complete remission rates were 84%; they were 78% for non-germinomas. Twenty-eight of 71 patients were alive without relapse or progression after a median 31 months of follow-up. The results are encouraging and chemotherapy-only treatment should be examined in further trials. (Balmaceda, J Clin Oncol 14:2908, 1996)