Showing papers by "International Agency for Research on Cancer published in 1973"

The predictive value of mouse liver tumour induction in carcinogenicity testing--a literature survey.

Abstract: A survey of the available data in the literature was carried out in an attempt to verify the possible correlation between the capacity of a number of chemicals to induce parenchymal liver tumours in the mouse and their capacity to induce tumours in the liver and/or other organs in the rat and hamster. Data on 58 chemicals were collected. A positive correlation appears to exist between the capacity of a chemical to induce liver tumours in the mouse and its capacity to induce tumours at any site in the rat or the hamster. The strongest correlation is found when the chemical, given to adult mice, induces tumours of the liver and other sites in both sexes. The induction of liver tumours in the mouse by a chemical does not signify that the liver would be the target organ in the rat or the hamster. Among the 58 chemicals considered, seven are recognized or suspected human carcinogens. All were hepatocarcinogenic in the mouse and six were carcinogenic in the liver and/or other organs in the rat. Four were tested in the hamster and found to be carcinogenic.

The effects of long-term feeding of DDT to BALB-c mice.

Abstract: A multigenerational study on the long-term effects of three dose levels of DDT (2, 20 and 250 ppm in the diet) and one dose level of N-nitrosodimethylamine (DMN) (0.0003% in the drinking water) was started in 1968. Each treatment was administered to two separate colonies of BALB/c mice. Treatment of parent mice started at 4-5 weeks of age. The results observed in the first two generations are presented in this report. Survival in males was poor because of fighting. In females, the highest dose level of DDT produced liver-cell tumours in 44% of the parent mice and 74% of the first generation mice, whereas no liver-cell tumours were found in mice given the control diet, or lower dietary concentrations of DDT. Liver cell tumours did not give metastases, but grew after transplantation to syngeneic mice. The ability of DDT to induce liver-cell tumours was identical in both colonies of mice given 250ppm DDT. Malignant lymphomas occurred in about 50% of the mice in all colonies given 0, 2 or 20 ppm DDT. In one of the two colonies given 250ppm DDT, the incidence of malignant lymphomas was 14%, whereas in the other it was 36%. The incidence of lung adenomas was not affected by DDT treatment. Tumours at sites other than liver, lymphatic system and lungs were highest in control mice and lowest in mice given 250 ppm DDT. However, no linear dose-response was found, and the decrease was more obvious in the parental than in the first generation. A study on the combinations of tumours in mice with more than one tumour and an analysis of litter distribution of liver-cell tumour-bearing mice did not reveal any particular trend in the distribution of liver-cell tumours. The quantitative aspects of tumour induction by DDT in BALB/c mice are compared with data from previous studies in mice. DMN consistently produced lung adenomas, liver blood cysts and haemangioendotheliomas.

Chlorinated hydrocarbon pesticides and related compounds in adipose tissue from people of Japan.

Abstract: HERE we report preliminary results on the presence of hexa-chlorobenzene (HCB) and polychlorinated biphenyls (PCBs) in addition to dichlorodiphenyl trichloroethane (DDT), dieldrin (HEOD), heptachlor epoxide (HE) and the three isomers of hexachlorocyclohexane (α,γ,β-HCCH) in Japanese autopsy adipose tissue. A total of 241 samples were taken at the Aichi Cancer Center Research Institute, Chikusa-Ka Nagoya, Japan.

Nasopharyngeal carcinoma. IV. Evolution of complement‐fixing antibodies during the course of the disease

Abstract: Sequential sera from 37 patients with nasopharyngeal carcinoma (NPC), with either controlled or uncontrolled tumours after radiotherapy, were studied for complement-fixing (CF) antibodies against a soluble antigen extracted from the QIMR-WIL lymphoblastoid line. When compared with results obtained previously with the same antigen on sequential Burkitt's lymphoma (BL) sera, the NPC sera exhibited (1) approximately ten-fold higher CF antibody titres than the BL sera; (2) an overall stability of CF titres in the uncontrolled tumour groups contrasting with the situation in BL; (3) a two- to four-fold decrease in CF titres in the controlled tumour groups; (4) similar CF titres in patients at stage I or IV of the disease. The above suggests an active and long-standing EBV infection before and during the development of the clinical NPC disease.

Cancer in its geographical perspective. The future of geographical pathology.

Abstract: Penile cancer: The distribution of this tumour is strongly influenced by circumcision habits. Great incidence variations have, however, been shown between tribes who do not practise circumcision. The incidence is particularly high, for instance, among the Banyoro and Iteso and low in the Madi and Lugbara in Uganda. None of these tribes circumcise, and this suggests additional etiological factors possibly relating to customs of hygiene (Schmauz & Jain 1971).