specific significance is attributed to a certain enzyme directed against type iv collagen , and to the auto-locomotion of tumor cells , properties that may also explain the highly selective process of metastazation in at least three consecutive steps : tumor cells invade a blood or lymph vessel , they are transported along blood or lymphatic pathways , and they eventually infiltrate foreign tissue after penetration and destruction of blood of lymph vessel walls .
C0229889
lymphatic
C0024202
lymph