In contrast to the Eμ-myc p53-/- tumors, the Eμ-myc Arf-/- seemed to be more dense in the peripheral regions (p = 0.002 on one end (Section S1) and p = 0.009 on the other end (Section S5)), whereas they were about the same for both tumor types in the intermediate sections S2 and S4. This evidence concerns the gene TP53 and neoplasm.