DEVELOPMENT OF HEMATOPOIETIC CANCERS AFTER IMPLANTATION OF TOTAL JOINT REPLACEMENT

The evidence from the 4 epidemiologic studies published before mid 199 5, which have investigated the incidence of cancers in patients who ha ve undergone joint implants, is conflicting, The results of the 2 earl ier studies suggested a sustained increase in the risk of lymphoma and leukemia after total hip arthro- plasty, The results of the 2 more re cent studies have not confirmed this, although in 1 study an increased risk was observed in the first year after implantation. The heterogen eity may be statistical in origin, but could also have a biologic expl anation in the greater proportion of metal on metal prostheses used be fore 1973. All 4 studies used national data as the comparison, Here ar e presented the results of 2 matched cohort studies and a case control study set in North America and Scotland, and an overview of the 4 pre vious studies. Neither the results of the matched studies of patients operated on after 1973 nor the results of the latter 2 published studi es suggest an increased risk of lymphoma or leukemia. If metal on meta l articulations are reintroduced, cartful surveillance is essential.