A study of porphyrin metabolism in ALL, non-Hodgkin’s lymphoma (NHL), and Hodgkin’s lymphoma (HL) showed a significant increase in the activity of 5-aminolevulinic acid dehydratase (ALAD) and Urinary porphyrinogen synthetase (URO-S), increased concentrations of total porphyrins, protoporphyrin, and urinary protoporphyrin in the blood, as well as a decrease in hemoglobin levels in patients with ALL, as compared with healthy controls (40). This evidence concerns the gene UROS and acute lymphoblastic leukemia.