Tracer Studies with Radioactive Phosphorus in Malignant Neoplastic Disease1

The success of Lawrence and his coworkers (1, 2) in the treatment of leukemia with radioactive phosphorus (P32) suggests that this isotope may also be of value in the treatment of certain malignant neoplasms. In order to obtain knowledge as to the immediate deposition of p32 in cancer tissue, small amounts of this isotope, about 0.5 microcurie, in the form of a 1.5 to 3.0 per cent solution of Na2HP04, have been administered at varying times before operation to patients with the following operable neoplasms: carcinoma of the breast, osteogenic sarcoma, lymphosarcoma. Small portions (about 2 grams) of the different tissues in the surgically excised specimens were weighed to 0.5 milligram, ashed at 500° C., and their radioactivity determined by direct comparison with accurately measured fractions of the original solution given to the patient. The final values were expressed in terms of microcuries per kilogram of tissue and were corrected for decay to the date of administration of the P32. Specimens with act...