KLK6 and neoplasm: The luminal surface area at 1 cm and 10 cm away from the tumor site was stained positively for KLK6 (p = 0.016 at 1 cm and p < 0.0001 at 10 cm), suggesting the increased KLK6 secretion by tumor cells and/or the presence of KLK6 in the morphologically normal tissue surrounding the tumor as well as in the distant areas.