More specifically, analyzing the number of proliferating cells in the top 100 μm of the tumour specimens using the proliferation marker Ki-67 did not bring up any significant differences between untreated controls (percentage of Ki-67+ cells 80.9 +/− 13.2%) and argon gas (71.9 +/− 17.6%, p= 0.2321). Here, MKI67 is linked to neoplasm.