International Agency for Research on Cancer (IARC) - Summaries & Evaluations


VOL.: 6 (1974) (p. 209)

5. Summary of Data Reported and Evaluation

(N.B.: This section should be read in conjunction with the section 'General Conclusions on Hormones'.)

5.1 Animal carcinogenicity data

Testosterone was tested by subcutaneous injection and/or implantation in mice, rats and hamsters.

Testosterone implanted subcutaneously induced cervical-uterine tumours in mice, which metastasized in some cases. The only study in rats was considered inadequate in numbers of animals.

The incidences of leukaemia and of liver-cell and breast tumours in untreated mice of some strains were decreased by testosterone treatment, but the incidence of mammary tumours was increased by neonatal treatment of females of a mammary-tumour-virus-bearing strain.

Three distinctive types of neoplasm were induced in hamsters by a combination of oestrogen and testosterone: a tumour of the uterine endometrium, a tumour of the vas deferens-epididymis and a basal-cell epithelioma of the flank. They remained dependent on oestrogen and testosterone for continued growth.

5.2 Human carcinogenicity data

No adequate epidemiological data on testosterone alone were available to the Working Group.

Subsequent evaluations: Vol. 21 (1979); Suppl. 7 (1987)

Last updated: 18 March 1998

    See Also:
       Toxicological Abbreviations
       TESTOSTERONE (JECFA Evaluation)
       Testosterone (PIM 519)
       Testosterone (IARC Summary & Evaluation, Volume 6, 1974)