Polymorphisms rs2631367 and rs2631372, described in the SLC22A5 gene encoding OCTN2, another member of the SLC22 family involved in etoposide [42] and imatinib [43] transport, have been related to the prognosis of some gastrointestinal tumors treated with imatinib [44]. This evidence concerns the gene SLC22A5 and digestive system neoplasm.