Effect of splenectomy on the growth of murine colon tumors.

We have previously demonstrated a high incidence of splenomegaly in BALB/c mice bearing colon tumor C-C36, but not colon tumor C-C26. To characterize this difference, tumor development in mice splenectomized seven days before tumor inoculation was compared to that of unoperated control mice. Our findings indicate that during the early phase, tumor growth is enhanced for both C-C26 and C-C36 in the splenectomized animals. The lag period for tumor appearance was also somewhat shorter in these splenectomized animals as compared to the controls, and metastatic tendency to the lungs was unaffected by splenectomy. These findings may have useful implications for the role of the spleen in the tumor-bearing animal.