Mitomycin-C

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Mitomycin-C

Definition

Mitomycin-C is also known as mitomycin and MMC. It is a medicine that kills cancer cells.

Purpose

Mitomycin-C may be used to fight a number of different cancers, including cancer of the stomach, colon, rectum, pancreas, breast, lung, uterus, cervix, bladder, head, neck, and esophagus.

It is impossible to provide a detailed description of how mitomycin-C may be combined with other medications in the treatment of each of these cancers, but some examples can be presented. In the treatment of non-small cell lung cancer (NSCLC), one therapeutic regimen that may be used is known as MT, which consists of mitomycin-C, vindesine , and cisplatin .

Mitomycin-C is sometimes used in patients with colorectal cancer metastatic to the liver. However, the side effects of mitomycin-C, especially those involving the bone marrow and fatigue , are so great that other medications may be tried first.

For advanced stomach cancer , the FAM regimen may be used, which consists of fluorouracil , doxorubicin (adriamycin), and mitomycin-C. Mitomycin-C may also be used for colorectal cancer metastatic to the liver in combination with other medicines.

Description

Mitomycin-C is an antitumor antibiotic. Mechanistically however, it belongs to DNA covalent binding (alkylating) agents. Mitomycin-C, upon bioactivation, kills cancer cells by disrupting the activity of DNA within the cells. DNA is an acid that contains genetic material.

Recommended dosage

Twenty milligrams per square meter should be given intravenously every six to eight weeks when this medication is used alone. Alternately, five to ten milligrams per square meter may be given every six weeks when the drug is used in combination with other drugs. Mitomycin-C, leucovorin , and fluorouracil may be used to treat metastatic rectal cancer ; this regimen includes an injection of 10 milligrams per square meter of mitomycin-C. When mitomycin-C is combined with vindesine and cisplatin in the treatment of non-small cell lung cancer, eight milligrams per square inch are administered intravenously on days one and twenty-nine of a six-week cycle.

Precautions

Because of the side effects associated with mitomycin-C, some physicians perform blood tests and order chest x rays (of the lungs) for patients receiving this therapy. The likelihood that lung problems will appear in patients receiving mitomycin-C increases if oxygen therapy and/or x-ray therapy are administered.

Patients receiving less than 60 mg of mitomycin-C are at reduced risk of developing a complex medical condition called cancer-associated hemolytic uremia syndrome (HUS). HUS is characterized by anemia , other blood defects, and kidney problems. Doctors should carefully observe patients receiving mitomycin-C, as cancer-related HUS is best treated early. However, HUS is not likely to develop until four or more months after the patient received the final dose of mitomycin-C. To achieve early diagnosis of HUS, the doctor may carefully monitor kidney function and blood levels. In addition, transfusions may be avoided as may be certain other procedures involving the blood, as these may increase the risk HUS will develop.

Side effects

The ability of the bone marrow to produce blood cells may be affected. This side effect can be serious. If it occurs, the doctor may decide to reduce the dose of medicine administered. However, mitomycin-C may cause delayed, rather than immediate, bone marrow suppression. Once such suppression does occur it may last for as many as eight weeks.

Major lung problems may occur. Such lung deficits may start as no more than cough, fatigue, and breathing problems. Doctors may conduct lung function tests and obtain x rays to observe whether lung problems are developing. If these lung problems do occur, corticosteroids may provide effective therapy. Stopping mitomycin-C therapy may also be recommended.

Mitomycin-C may also cause cancer-associated HUS.

In addition, there may be nausea and vomiting , loss of appetite (anorexia ), stomach problems, fatigue, fever , hair loss (alopecia ), and lung problems. If bleeding does occur, there may be damage to the surrounding skin.

Bob Kirsch