Oncogenic transforming potential of etanidazole.
The 2-nitroimidazole etanidazole is in Phase III randomized trials as an adjunct to radiotherapy in both the United States and Europe. Paradoxically, it is one of the more oncogenic radiosensitizers examined with the in vitro oncogenic transformation assay based on C3H 10T1/2 cells. To obtain an estimate of the possible number of second malignancies that might be induced in patients receiving the drug, the in vitro transformation assay was used to compare etanidazole with gamma-rays, for which cancer risk estimates are available from the Japanese survivors. For the clinical protocol used in RTw] studies, which results in a cumulative dose of 36 mM hr, the drug-induced cancer incidence was estimated to be 2.8 to 14%.
Hall
E J
EJ
Center for Radiological Research, College of Physicians and Surgeons, Columbia University, New York, NY 10032.
Hei
T K
TK
D000818:Animals; D002460:Cell Line; D002471:Cell Transformation, Neoplastic / Q000139:chemically induced*; D017341:Etanidazole; D051379:Mice; D016609:Neoplasms, Second Primary; D009593:Nitroimidazoles / Q000633:toxicity*; D011838:Radiation-Sensitizing Agents / Q000633:toxicity*; D012306:Risk
D009593:Nitroimidazoles; D011838:Radiation-Sensitizing Agents; D017341:Etanidazole