indication

For treatment of malignant neoplasm of lip, oral cavity, pharynx, digestive organs, peritoneum, female breast, and urinary bladder. Also used as an adjunct to ab externo glaucoma surgery.

pharmacology

Mitomycin is one of the older chemotherapy drugs, which has been around and in use for decades. It is an antibiotic which has been shown to have antitumor activity. Mitomycin selectively inhibits the synthesis of deoxyribonucleic acid (DNA). The guanine and cytosine content correlates with the degree of mitomycin-induced cross-linking. At high concentrations of the drug, cellular RNA and protein synthesis are also suppressed. Mitomycin has been shown in vitro to inhibit B cell, T cell, and macrophage proliferation and impair antigen presentation, as well as the secretion of interferon gamma, TNFa, and IL-2.

mechanism of action

Mitomycin is activated in vivo to a bifunctional and trifunctional alkylating agent. Binding to DNA leads to cross-linking and inhibition of DNA synthesis and function. Mitomycin is cell cycle phase-nonspecific.

toxicity

Oral, mouse: LD₅₀ = 23 mg/kg; Oral, rat: LD₅₀ = 30 mg/kg. Symptoms of overdose include nausea and vomiting.

biotransformation

Primarily hepatic, some in various other tissues.

absorption

Erratic.

half life

8-48 min

route of elimination

Approximately 10% of a dose of mitomycin is excreted unchanged in the urine.

drug interactions

Trastuzumab: Trastuzumab may increase the risk of neutropenia and anemia. Monitor closely for signs and symptoms of adverse events.

Vinblastine: Potentially severe lung toxicity

Vincristine: Potentially severe lung toxicity

Vindesine: Potentially severe lung toxicity