Mitomycin Injection 10 MG â 40 MG offered, is an antibiotic that is only used in the treatment of cancer. It inhibits or stops cancer cell growth in your body. This product is a medication that is used in combination with other treatments to treat cancers of the stomach and pancreas. It works by slowing or preventing cancer cell proliferation. Mitomycin Injection 10 MG â 40 MG belongs to the anti-cancer class of drugs used in cancer treatment. It's most beneficial for advanced metastatic stomach cancer patients.