in the literature as individual reports. The disease does not appear to be endemic, having a generalized distribution throughout the world. The majority of cases in the literature have been of the meningeal form ; however, a few reports have presented only pulmonary, cutaneous, or osseous involvement. A variety of therapeutic agents have been employed with generally disappointing results. Evaluation of therapy has been made difficult because of scattered, individual case reports as well as spontaneous remissions seen in this disease. We therefore urge the report of all such cases and present one of our own. In presenting this case we have two considerations ; therapy with 2-hydroxystilbamidine and the significance of a coexisting granulomatous process.
A recently developed slide-chamber method was used to test the radiosensitivity of blood lymphocytes from 80 patients with chronic lymphocytic or lymphosarcoma-cell leukemia. The objective of this study was to determine whether these in vitro tests on sensitivity to x-rays had any clinical significance.
Two objective criteria were used to measure the clinical reactions of the leukemic patients. The first was the duration of survival of patients following the in vitro test. The second was the minimal leukocyte count of a patient following x-ray therapy; the minimal count was expressed as a percentage of the count before therapy.
The in vitro radiosensitivity was measured by the 10 per cent survival time of lymphocytes irradiated with 1000 r. Blood lymphocytes from non-leukemic individuals were highly radiosensitive with indices of 1.1 to 2.2 days. In initial tests, the lymphocytes of 61 leukemic patients had the same high sensitivity to x-rays as lymphocytes from non-leukemic individuals. In contrast, the lymphocytes of 19 leukemic patients were radioresistant to irradiation with indices of 2.5 to 11 days.
The 61 patients with radiosensitive lymphocytes had a median survival time of 22 months after the in vitro test. In contrast, the 19 patients with radioresistant lymphocytes had a median survival time of only 4 months. Clinical x-ray therapy caused a greater decline in leukocyte counts in patients with radiosensitive lymphocytes than in those with radioresistant cells.
A significant index of 0.60 was obtained for the correlation of in vitro radiosensitivity of lymphocytes and the in vivo decrease in leukocyte counts of patients after x-ray therapy.
It is concluded that an in vitro finding of radioresistant lymphocytes is correlated with a poor response of the leukocyte count to x-ray therapy and a short survival time of the patient.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.