Invasiveness invitro versus clinical evolution of primary and secondary brain-tumors.

Cells of 56 primary cell cultures derived from primary and secondary brain tumours were confronted in vitro with host tissue, embryonic chick heart fragments (PHF). The evolution of the confrontation was followed for one week. Histological analysis of the confrontations demonstrated two different patterns. (i) Survival of host tissue and tumour derived cells without invasion of the last ones into the host. (ii) Invasion of tumour derived cells into the host tissue followed by replacement of the chick heart tissue. Invasion into the host tissue was observed only in the confrontations with primary cell cultures originating from malignant and metastatic tumours. The invasive characters in vitro of primary cell cultures correlated with the malignancy of the tumour in vivo.