Two cases of parathyroid carcinoma in patients on long-term hemodialysis.

Two cases of parathyroid carcinoma, in a 46-year-old male on maintenance hemodialysis for 135 months and a 55-year-old female on maintenance hemodialysis for 64 months were reported. In both cases, the parathyroid carcinoma showed local invasion and the other glands were hyperplasia and/or adenoma, which would support the concept of malignant transformation occurring in parathyroid hyperplasia. The concurrence of parathyroid carcinoma with hyperplasia and/or adenoma is a pertinent feature in patients on maintenance dialysis, although it is rare in primary parathyroid carcinoma.