Mitomycin

Indications

Mitomycin is used for: Solid tumours, non-invasive bladder cancer, stomach cancer, pancreas cancer, metastatic breast cancer, advanced cervical cancer, anal carcinoma

Adult Dose

Intravenous Solid tumours The usual dose is in the range of 4-10 mg (0.06-0.15 mg/kg) given at 1-6 weekly intervals depending on whether other drugs are given in combination and on bone marrow recovery. In a number of combination schedules, the dose is 10 mg/m2 of body surface area, the course being repeated at intervals for as long as required. A course ranging from 40-80 mg (0.58-1.2 mg/kg) is often required for a satisfactory response when used alone or in combination. A higher dosage course may be given when used alone or as part of a particular combination schedule and total cumulative doses exceeding 2 mg/kg have been given. Intravesical Superficial bladder tumours In the treatment of superficial bladder tumours the usual dose is 20-40 mg dissolved in 20-40 ml of diluent, instilled into the bladder through a urethral catheter, weekly or three times a week for a total of 20 doses. The dose should be retained by the patient for a minimum of one hour. During this one-hour period the patient should be rotated every 15 minutes to ensure that the Mitomycin-C comes into contact with all areas of the bladder urothelium. When the bladder is emptied in the voiding process, care must be taken to ensure that no contamination occurs locally in the groin and genitalia areas. In the prevention of recurrent superficial bladder tumours, various doses have been used. These include 20 mg in 20 ml of diluent every two weeks and 40 mg in 40 ml of diluent monthly or three monthly. The dose is instilled into the bladder through a urethral catheter. In both cases, the dose should be adjusted in accordance with the age and condition of the patient.

Child Dose

Safety and efficacy not established

Renal Dose

Renal Impairment Serum creatinine >1.7 mg/dL: Avoid use CrCl <10 mL/min: Decrease dose by 25% CAPD: Decrease dose by 25%

Administration

IV Preparation Reconstitute with SWI to a concentration of 0.5 mg/mL IV Administration Administer slow IV push by central line only Flush with 5-10 mL of IV solution before & after drug administration

Contra Indications

Hypersensitivity. Patient w/ platelet counts <100,000/mm3, leukocyte counts <4,000/mm3 or serum creatinine concentration >1.7 mg/dL. Patient w/ substantial prolongation of prothrombin time or bleeding time, coagulation disorders, increased bleeding tendency. Pregnancy and lactation.

Precautions

Patient w/ bone marrow depression, infections including varicella infection. Hepatic or renal impairment. Patient Counselling This drug may cause generalised weakness and lethargy, if affected, do not drive or operate machinery. Monitoring Parameters Repeated haematologic studies (platelet count, leukocyte count, differential, prothrombin time, bleeding time and Hb determinations) are necessary during therapy and for at least 7 wk following discontinuance of the drug. Carefully monitor LFTs and renal function test. Lactation: Not known if excreted in breast milk, do not nurse

Pregnancy-Lactation

Pregnancy Category: D Lactation: Not known if excreted in breast milk, do not nurse

Interactions

Increased incidence of cardiotoxicity w/ doxorubicin. Potentially Fatal: Increased risk of intravascular haemolysis and renal failure w/ fluorouracil. Increased risk of haemolytic uraemic syndrome w/ tamoxifen. Acute pulmonary toxicity w/ vinca alkaloids (e.g. vinblastine, vinorelbine). Increased bone marrow depressant effects of aclarubicin.

Adverse Effects

Side effects of Mitomycin : >10% Hemolytic uremic syndrome (≤15%), Myelosuppression (64%), Nausea/vomiting (14%), Fever (14%) 1-10% Stomatitis (4%), Increased serum creatinine (2%), Mucous membrane toxicity (4%) Frequency Not Defined Fatigue, Pulmonary toxicity, Dyspnea, Cystitis, Interstitial fibrosis, Nephrotoxicity, Amenorrhea, Alopecia Potentially Fatal: Myelosuppression, haemolytic-uraemic syndrome.

Mechanism of Action

Mitomycin is an antineoplastic antibiotic which is enzymatically reduced to its active metabolite w/in susceptible cells. The active metabolite appears to cause cross-linking of DNA (primarily w/ guanine and cytosine pairs). It is also active against gm+ve bacteria and some viruses.