Mitomycin C, often referred to simply as mitomycin, is used as a cytotoxic antibiotic. It belongs to the mitomycin group and is the only approved chemotherapeutic agent from this group.
What is mitomycin C?
The antibiotic mitomycin was isolated from Streptomyces caespitosus in 1958 and is effective against some viruses as well as gram-positive bacteria. It is now used only as a cytostatic agent in the treatment of various carcinomas and in the prevention of bladder cancer. Mitomycin C is administered intravenously or intravesically (into the bladder). The active substance inhibits the growth or division of tumor cells. Mitomycin is a blue-violet crystalline powder that is used to prepare a solution for injection or infusion. In Germany, it is available in the form of monopreparations under the trade names Amétycine, Mitem, Mito-medac or Urocin. Various generics of mitomycin are also available in both Germany and Austria.
Pharmacologic effects on the body and organs
Mitomycin C belongs to both the antibiotics and the cytostatic group. After metabolization, the active substance exerts a cell-killing effect. This is where the actual active substance is formed. After enzymatic activation, DNA synthesis is inhibited and mitocymin is inserted between two DNA strands. As a result, the two strands are firmly bonded together and separation of the DNA strands is no longer possible. This process prevents the proliferation of tumor cells. The drug is administered intravenously. Afterwards, a high concentration of mitomycin C can be found in the heart, kidneys, lungs, muscle, bile, tongue and urine. However, there is rapid inactivation of the substance by enzymes in the liver, spleen, heart and kidneys. Mitomycin is excreted primarily by the kidneys. As part of the use of mitomycin in intravesical chemotherapy, efficacy can be optimized by urinary alkalinization.
Medical use and use for treatment and prevention.
Mitomycin C has many uses in cancer. Among others, it is used in the treatment of bladder cancer, breast cancer, cancer of the colon and rectum, hepatocellular cancer, cervical cancer, esophageal cancer, head and neck cancer, pancreatic cancer, stomach cancer, bronchial cancer, or osteosarcoma (malignant bone tumors) and blood cancer (leukemia). Mitomycin C is also used in hyperthermic intraperitoneal chemotherapy (HIPEC, treatment for tumor involvement of the peritoneum). Mitomycin must not be used in cases of hypersensitivity to the active substance, bleeding tendency, reduced bone marrow function, poor general condition, existing cystitis (if it is to be used in the bladder) and damage to the kidneys, lungs and liver. Therapy must be discontinued immediately if pulmonary symptoms develop during the course of therapy that are not associated with the underlying disease. Treatment must also be stopped in cases of anemia and renal dysfunction. Women who are of sexually mature age should take measures to prevent pregnancy during and up to 6 months after treatment with mitomycin C. In addition, because of the proven development of malformations in the unborn child, mitomycin should not be used during pregnancy or lactation.
Risks and side effects
Side effects may also occur when mitomycin C is administered. These may or may not occur. Each person reacts differently to medications, which is why the possible side effects can be differentiated by type of frequency. Very common side effects associated with the use of mitomycin C include nausea and vomiting, and bone marrow dysfunction associated with a lack of platelets and white blood cells. Common side effects include cough, shortness of breath, shortness of breath, pneumonia, localized or allergic skin rash, redness of hand and foot surfaces, contact dermatitis, an increase in creatinine in the blood, kidney dysfunction, or even filter cell disease in the kidney. If mitomycin is used in the bladder, side effects may include bladder inflammation, problems with urination, very frequent urination, urinary urgency at night, and local irritation of the bladder wall.Injection into tissues may also cause inflammation of the cells or tissue death. Hair loss, inflammation of the mucous membranes and oral mucosa, fever or even diarrhea are occasional side effects of mitomycin. Rare to very rare side effects include increased enzyme levels in the blood, liver dysfunction, loss of appetite, jaundice, anemia, sepsis, pulmonary hypertension, cardiac insufficiency, severe allergic reactions, or even death of bladder tissue when used in the bladder. If other drugs or substances are taken at the same time, the effect of mitomycin may change. Thus, when substances that damage bone marrow are taken at the same time, the negative effects complement each other. If mitomycin is taken in combination with vinca cytostatics (e.g., vincristine) or the antibiotic bleomycin, the harmful effect of mitomycin on the lungs increases. Vaccination with live vaccines should not be given while taking mitomycin C because of the weakened immune system, otherwise infections may occur. In addition, mitomycin may increase the harmfulness of adriamycin to the heart. Mityomycin C should generally be administered only by physicians experienced in cancer therapy. Injection is intended only into the blood vessels; it must not enter surrounding tissues. If nausea and vomiting occur due to the use of mitomycin, there may be a change in the ability to react. Driving a car or operating machinery then becomes a danger. Reaction is also impaired if alcohol is consumed at the same time. If patients experience side effects not listed here, the attending physician must be consulted immediately.
