Therapeutic potential of intravenous 67-gallium in non-Hodgkin's lymphoma.

67-gallium accumulates rather selectively in malignant lymphoid tissue. The isotope has a substantial cytotoxic effect in human-derived cell-lines. 67-gallium was given intravenously to 3 patients with end-stage, resistant large-cell lymphoma. Evaluation of tumour response was done by physical measurements, and CT-scanning together with gallium scintigraphy. Three weekly doses of 20, 40 and 60 mCi respectively caused persistent pancytopenia in 1 patient. Pancytopenia was not observed in 2 other patients given two 40 mCi doses 4 weeks apart. In all 3 patients, some response was noted, be it shortlived and different from site to site. 67-gallium has some cytostatic effect in large cell lymphoma. It seems feasible to start a phase I study to find a tolerable dose to be given every 4 weeks.