International Agency for Research on Cancer (IARC) - Summaries & Evaluations
VOL.: 24 (1980) (p. 59)
5. Summary of Data Reported and Evaluation
5.1 Experimental data
Dapsone has been tested by oral administration in mice and rats, by
intraperitoneal administration in mice and by prenatal and lifetime
oral exposure in mice and rats. In three different studies in rats,
high doses of dapsone induced mesenchymal tumours of the spleen in
males (and of the peritoneum in two studies). An increased incidence
of tumours of the thyroid was found in rats of both sexes in one study
and in males in another study.
In mice, the experiment involving intraperitoneal administration of
dapsone could not be evaluated. The other two experiments did not
provide evidence of carcinogenicity.
Dapsone and its acetylated metabolites were not mutagenic to
Salmonella typhimurium. Attention is drawn to the absence of studies
on the teratogenicity of this compound.
5.2 Human data
Dapsone is used mainly in the treatment of leprosy.
Several cases of cancer have been reported in patients with dermatitis
herpetiformis treated with dapsone. There was no evidence of an
increased rate of cancer in patients with leprosy, many of whom would
also have been treated with the drug.
There is limited evidence for the carcinogenicity of dapsone in
experimental animals. The epidemiological data were insufficient. No
evaluation of the carcinogenicity of dapsone to humans can be made.
For definition of the italicized terms, see Preamble Evaluation.
Subsequent evaluation: Suppl. 7 (1987)
Last updated: 7 April 1998