Local tumor immunotherapy with in vitro activated autochthonous lymphocytes

The use of lymphocytes in tumor immunotherapy was studied by the local intra‐tumor injection of in vitro activated autochthonous lymphocytes. In 15 patients with diverse malignant tumors, 29 subcutaneous metastatic nodules were injected with autochthonous lymphocytes activated by in vitro incubation with phytohemagglutinin (PHA) for 24 hours. Two tumors regressed completely, 25 regressed partially (range 22 to 95%, mean decrease 71%), one did not change, and one increased 65% in size. Seven of 18 nodules injected with nonactivated but in vitro incubated autochthonous lymphocytes regressed partially (range 20 to 93%, mean decrease 59%), 3 did not change, and 8 increased in size (range 17 to 1,520%, mean increase 265%). Of the 28 saline‐injected and uninjected tumors, 2 regressed in size 33% and 36%, respectively, 4 remained static, and all of the rest grew during the study period (range 25 to 1,072%, mean increase 195%). The potential of this approach to therapy should be explored further.