The influence of thymectomy on Rous sarcoma regression.

The incidence of regression of wing-web tumors induced by Rous sarcoma virus was shown to be dependent on the quantity of thymus tissue remaining after neonatal thymectomy in chickens of inbred line 6. Frequency of metastasis was associated negatively with the amount of thymus tissue present. Tumor regression and metastasis restriction both appeared dependent on the quantity of thymic tissue present.