Rhabdomyosarcoma, dactinomycin

Dactinomycin is useful against several tumors especially Wilms tumor of the kidney and rhabdomyosarcoma. Wilms tumor normally requires a combination of surgery, x-ray irradiation, and dactinomycin plus vincristine [57-22-7] or other antitumor agents. Resistance of the multidmg... 

Dactinomycin is used in curative combined treatment of Wilms tumor, Ewing s sarcoma, rhabdomyosarcoma, and gestational choriocarcinoma. It is active in testicular tumors, lymphomas, melanomas, and sarcomas, although its use in most of these malignancies has been supplanted by other agents. 

Dactinomycin Cosmegen Carcinoma of testicle and endometrium carcinosarcoma of kidney [Wilms tumor] Ewing sarcoma rhabdomyosarcoma Blood disorders [leukopenia, thrombocytopenia, others] Gl distress [nausea, vomiting, loss of appetite] mucocutaneous lesions skin disorders [rash, hair loss] local irritation at injection site... 

The antibiotics that bind to DNA are nonspecific to the cell-cycle phase. Dactinomycin (actinomycin D and Cosmegen) binds to double-stranded DNA and prevents RNA synthesis by inhibiting DNA-dependent RNA polymerase. It is administered intravenously in the treatment of pediatric solid tumors such as Wilms tumor and rhabdomyosarcoma and for gestational choriocarcinoma. Dactinomycin causes skin reactions, gastrointestinal injury, and delayed bone marrow depression. 

Dactinomycin is mainly used to treat pediatric tumors such as Wilms tumor, rhabdomyosarcoma, and Ewing s sarcoma, but it has activity also against germ cell tumors and gestational trophoblastic disease. Dactinomycin can also induce a "radiation recall reaction." See Table 55 1 for other toxi cities. 

The most important clinical use of dactinomycin is in the treatment of rhabdomyosarcoma and Wilms tumor in children, where it is curative in combination with primary surgery, radiotherapy, and other drugs, particularly vincristine and cyclophosphamide. Antineoplastic activity has been noted in Ewing s tumor, Kaposi s sarcoma, and soft-tissue sarcomas. Dactinomycin can be effective in women with advanced cases of choriocarcinoma in combination with methotrexate. Dactinomycin also has been used as an immunosuppressant in renal transplants. 

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