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


VOL.: 26 (1981) (p. 311)

5. Summary of Data Reported and Evaluation

5.1 Experimental data

Procarbazine hydrochloride is carcinogenic in mice and rats after its intraperitoneal administration, producing malignant tumours of the nervous system, haematopoietic system and possibly other organs in both species, and tumours of the mammary gland in rats only. Evidence of carcinogenicity was also found in mice and rats following its oral administration, in rats following its intravenous administration, and in one instance following transplacental exposure. Two studies in two species of nonhuman primates suggest that procarbazine hydrochloride may also produce myelogenous leukaemia when administered by multiple routes in the same animal.

Procarbazine hydrochloride can induce teratogenic effects in rats and embryolethality at doses nontoxic to the mother. This compound is mutagenic in bacteria, yeast, cultured mammalian cells and Drosophila melanogaster, and in mice and rats in vivo.

5.2 Human data

Procarbazine hydrochloride is used primarily in the treatment of Hodgkin's disease, non-Hodgkin's lymphoma and lung cancer, in combination with other drugs.

The available data are insufficient to evaluate the teratogenicity, mutagenicity or chromosomal effects of procarbazine hydrochloride in humans.

Both case reports and epidemiological studies indicate that acute nonlymphocytic leukaemia is produced in patients with Hodgkin's disease treated with combined therapeutic regimens which include vinca alkaloids, alkylating agents and procarbazine hydrochloride, often in conjunction with radiotherapy. No data were available to the Working Group which permit the assessment of the separate effects of procarbazine hydrochloride.

5.3 Evaluation

There is sufficient evidence for the carcinogenicity of procarbazine hydrochloride in mice and rats. There is limited evidence of its carcinogenicity in monkeys. There is sufficient evidence for the carcinogenicity in humans of intensive chemotherapeutic regimens that include alkylating agents, vinca alkaloids, procarbazine hydrochloride and prednisone. There is inadequate evidence of the carcinogenicity of procarbazine hydrochloride alone in humans.

On the basis of the combined experimental and human evidence, this compound should be considered for practical purposes as if it presented a carcinogenic risk to humans.

For definition of the italicized terms, see Preamble Evaluation.

Subsequent evaluation: Suppl. 7 (1987)

Last updated: 8 April 1998

    See Also:
       Toxicological Abbreviations
       Procarbazine Hydrochloride (IARC Summary & Evaluation, Supplement7, 1987)