Overt malignancy in long-term hemodialysis patients.

We studied all 39 patients who were on maintenance hemodialysis for 10 years or more (range, 10 to 24 years) in three free-standing, not-for-profit hemodialysis units to determine the prevalence of malignancy. The three dialysis units have a total patient population of 470, all of whom are cared for by the same group of physicians. From the same dialysis units, we selected a control cohort of 37 patients matched for age, gender, race, and renal diagnosis who were on hemodialysis for 3 years or less (short-term patients). Control patients were selected by randomly choosing the next patient who filled the criteria for duration of dialysis from the roster of all patients at a facility. Clinically overt malignancy during dialytic therapy was determined by history, physical examination, Pap smear, mammogram, and colonoscopy in patients with gastrointestinal bleeding. The mean age (+/-SE) of the long-term patients was 51.8 +/- 1.9 years, and that of the control group was 51.5 +/- 2.4 years (P = .92). Thrice-weekly hemodialysis prescriptions were similar in both groups: long term, 3.5 +/- 0.02 hours; control, 3.4 +/- 0.02 hours (P = .27). No malignancy was detected in either the long-term or the short-term patients, and no patient of either group had a malignancy in the past. Colonic biopsy specimens of four long-term patients who had gastrointestinal bleeding were normal. The prevalence of malignancy was not increased in patients who were on maintenance hemodialysis for 10 years or longer.