[Significance of splenectomy in the treatment of cancer].

With inoculation of a large amount of tumor cells, the tumor growth of splenectomized mice was depressed compared to sham operated mice. On the contrary, with inoculation of a small amount of tumor cells the occurrence of tumor was lower in sham-operated mice. The effect of splenectomy on tumor growth was bidirectional depending on the dose of the inoculate. The effect was due to the production of the immunosuppressive factor in sera obtained from mice inoculated with a large but not small amount of tumor cells. Studies for the late survivals of 113 patients who had received curative total gastrectomy with or without splenectomy revealed that the non-splenectomized group showed a significantly better late survival rate than the splenectomized group when the splenic hilar lymph nodes were not involved with cancer metastasis.