Abstract
Frequencies of various malignant neoplasms among 979 patients (614 males [M], 365 females [F]) who were hemodialyzed at the San-ai Memorial Hospital, Chiba, from January 1987 to August 1997 were determined by the person-year method. In this period, malignancy developed in 57 patients (39M, 18F) which consisted of 14 cancers of the large intestine, 10 of the stomach, 7 kidney, 6 lung, 5 thyroid, 4 breast, 2 each of ovary and esophagus, and 1 each of liver, urinary bladder, duodenum, mesopharynx, multiple myeloma, malignant lymphoma and melanoma. The incidence for each organ in 100, 000 person-years was: 272.9(M) and 329.6(F) for the colon, 272.9 and 109.9 for the stomach, 204.6 and 54.9 for the kidney, 136.4 and 109.9 for the lung, and 136.4 and 54.9 for the thyroid, making the total of all cancers 1330.3 and 988.7. The expected figures in the control were calculated from the age-specific incidence rates in selected areas of Chiba Prefecture for 1991-1993, and were compared with the actual incidence in this hospital. The overall (M+F) number of malignancies relative to the expected number was 2.6 times (p<0.05). This ratio varied considerably with the organ, the thyroid having the highest figure, 24.2 times the expected. However, all thyroid cancers were latent, being discovered at the time of parathyroidectomy, and should be excluded. The ratios significantly exceeded 1.0 in cancers of the kidney (16.2) and large intestine (4.2). By contrast, liver cancer was the only malignancy that showed a figure lower than expected. It was concluded that in maintenance dialysis patients, certain but not all organs tend to develop malignancy at a higher rate than in nondialysis subjects.
