PROLIFERATIVE RESPONSE OF HUMAN AND ANIMAL TUMORS TO SURGICAL WOUNDING OF NORMAL-TISSUES - ONSET, DURATION AND INHIBITION

Acceleration of secondary tumour growth and metastases following excis ion of a primary tumour has been attributed to the consequent removal of primary tumour-generated inhibitory factors. However, our studies h ave shown that surgical wounding of normal tissues significantly stimu lated the growth of malignant tissues without the concomitant presence or excision of a tumour mass. A humoral stimulating component was ind icated by the proliferative response of rumours and metastases distant from the surgical wound. All 16 human and murine tumours, of nine dif ferent histologies, showed a measurable acceleration of growth when im planted in surgically treated animals, suggesting that the ability of malignant tissue to respond to surgical wounding of normal tissue was not histologically or species specific. The proliferative surge of mal ignant tissues was detectable soon after wounding and had a duration o f 2-3 days. The surgical wound as the source of the tumour-stimulating factor(s) was affirmed by the significant inhibition of tumour prolif erative responses when a somatostatin analogue was applied topically t o the surgical wound within 1 h of wounding, and/or during the critica l tumour-stimulatory period of 1-2 days after wounding. A potential th erapeutic window for reducing a risk factor that may be inadvertently imposed upon every surgical/oncology patient is indicated.