Enhancing effect of thoracotomy on tumor growth in rats.

To indicate the influence of operative stress on tumor growth, thoracotomy and/or laparotomy were performed 48 hr after intraperitoneal or intravenous inoculation of Sato lung cancer into Donryu rats. Survival period, number of metastatic nodules on the surface of the lungs, and the percentage-area of metastases in the frontal section through pulmonary hilus were examined. By thoracotomy and laparothoracotomy the survival period of the tumor-inoculated rats was reduced significantly compared with that of the control but difference between these two test groups was not significant. Also there was no significant difference between the laparotomy group and the control. The results obtained in the number and percentage-area of metastatic nodules were quite similar to that observed in the survival period. Correlation between the number and the percentage-area of metastatic nodules was highly significant. The meaning of the stress of thoracotomy in cancer treatment is discussed.