thorium-x and Leukemia--Myeloid

In German-speaking countries, the intravenous treatment of ankylosing spondylitis (AS) with radium-224 ((224)Ra) was common between the late 1940s and 2005. In this long-term investigation, the risk of malignant diseases following intravenous (224)Ra treatment for AS was assessed.. In a prospective long-term study, 1,471 patients with AS who were treated with (224)Ra between 1948 and 1975 have been followed together with a control group of 1,324 AS patients treated neither with radioactive drugs nor with X-rays. Standardized questionnaires to evaluate the patients' health status were used. Observed numbers of malignant diseases were compared with those of the control group as well as with expected numbers for a normal population.. After 26 years of follow-up, causes of death have been certified for 1,006 patients of the exposure group (control group: 1,072 patients). Significantly increased rates of myeloid leukemia (12 cases observed vs. 2.9 expected; p < 0.001), kidney cancer (18 vs. 9.1; p < 0.01), thyroid cancer (4 vs. 1.2; p = 0.03) and borderline significantly increased rates of cancer of female genital organs (10 vs. 5.6; p = 0.06) were found in the exposure group in contrast to no significant increases of these diseases in the control group. Rates of pulmonary and gastrointestinal malignancies were not increased. Lymphatic leukemia (exposure group: 8 vs. 2.7; p < 0.01; control group: 7 vs. 3; p = 0.03) was significantly elevated due to a high rate of chronic lymphatic leukemia in both, the exposure as well as the control group.. Treatment of AS with (224)Ra led to increased incidences of myeloid leukemia and malignancies of kidneys, thyroid and female genital organs. Although this kind of therapy is now abandoned, there is a need for close follow-up of patients who received it.

Topics: Female; Genital Neoplasms, Female; Humans; Kidney Neoplasms; Leukemia, Myeloid; Male; Neoplasms, Radiation-Induced; Radium; Spondylitis, Ankylosing; Thorium; Thyroid Neoplasms

To investigate long-term health effects in AS patients treated with (224)Ra.. A prospective epidemiological study has been carried out on 1471 AS patients treated with repeated intravenous injections of (224)Ra between 1948 and 1975. These patients have been followed together with a control group of 1324 AS patients not treated with radioactive drugs and/or X-rays. Numbers of malignancies expected in a normal population were computed from German and Danish cancer registry data.. After a mean follow-up time of 26 yrs in the exposed group or 25 yrs in the control group, causes of death have been ascertained for 1006 exposed patients and 1072 controls. In particular, 19 cases of leukaemia were observed in the exposure group (vs 6.8 cases expected, P < 0.001) compared to 12 cases of leukaemia in the control group (vs 7.5 cases expected). Further subclassification of the leukaemia cases demonstrated a high increase of myeloid leukaemia in the exposure group (11 cases observed vs 2.9 cases expected, P < 0.001), especially a high excess of acute myeloid leukaemias (7 cases observed vs 1.8 cases expected, P = 0.003), whereas in the controls the observed cases are within the expected range (4 myeloid leukaemias vs 3.1 cases expected).. The enhanced leukaemia incidence in the exposed group is in line with results from experiments in mice injected with varying amounts of the bone-seeking alpha-emitter (224)Ra. In these studies, in animals exposed to lower doses of (224)Ra, i.e. at doses lower than those found to induce osteosarcomas, an increased risk of leukaemia was observed.

Topics: Adult; Aged; Aged, 80 and over; Denmark; Epidemiologic Methods; Female; Germany; Humans; Leukemia, Myeloid; Leukemia, Myeloid, Acute; Leukemia, Radiation-Induced; Male; Middle Aged; Radium; Spondylitis, Ankylosing; Thorium