 Investigators will assess the effects of inherited genome variations on treatment-induced peripheral neuropathy that persists in adults who were cured of childhood cancer. Cells from childhood cancer survivors who did or did not develop drug-induced neuropathy will be isolated and induced to become neurons. Cell sensitivity to anticancer agents will be tested in both groups and compared to determine if the survivors have genetic variants that correspond to those identified in companion genomic studies. This will assist in determining if gene variants increase the risk of treatment-induced neurotoxicity. 