Investigators in St. Jew Childrens Research Hospital have shown that if the cancer drug irinotecan is in small doses over several days, it eliminates the need to delay the treatment is too expensive genetic tests to determine if the patient has a risk of serious side effects of treatment As neutropenia. Neutropenia is an abnormal decrease in the number of immune cells, neutrophils, the disorder leaves individuals vulnerable to infections.
UGT1A1 is an enzyme that changes the activated form of irinotecan, a molecule called SN-38, so that the body can easily remove. Variations of this enzyme, especially one called UGT1A1 * 28, do not work as well and allow SN-38 to remain in the body at a high level for an extended period, leading to adverse effects.
The finding means that clinicians can begin treatment more quickly and eliminate the cost of this particular test, which determines if the child has a change in gene UGT1A1 associated with this side effect neutropenia. Through the influence of the drug in small doses for two weeks instead of the standard is a large dose once a month, children can begin treatment with irinotecan immediately. Irinotecan is for the treatment of childhood solid tumors such as neuroblastoma, sarcoma and kidneys.