[Parathyroidectomy and autotransplantation in renal hyperparathyroidism. II. Morphologic and functional studies in transplant-dependent recurrence].

Corresponding to predefined macroscopic criteria indicating morphological and functional characteristics, fragments of a type 1a-gland were used after total parathyroidectomy for auto-transplantation in 16 hemodialyzed patients with drug-resistant renal hyperparathyroidism (rHPT). Fragments of a type 1b-gland were used in two, fragments of a type 2-gland in 17 patients, respectively. The clinical and biochemical follow-up three to 84 months postoperatively showed one patient (3%) with graft-dependent hypocalcemia (type 1a-graft) and in two patients (6%) with type 2-grafts histological examinations confirmed graft-dependent recurrent hyperparathyroidism. Thus the estimated cumulative success (= normal parathyroid metabolism; Kaplan Meier) was 78 +/- 12% 5 years postoperatively. Comparing the estimated cumulative function rate of type 1a- and type 2-autotransplants, a better course was found in typ 1a-grafts three years postoperatively (Breslow: p = 0.0724; Mantel-Cox: p = 0.0677). The morphological examinations of the removed enlarged fragments of different size (between 0.2 cm and 0.9 cm) showed signs of an expansive, but never invasive growth. The chief and oxyphilic cells were intermixed and arranged in a follicular pattern as in the former glands selected for grafting. Mitoses could be found more often in larger fragments, thus correlating with a tendency to proliferation and a bad in vitro suppressibility. The results of the studies confirm the conclusions of an in vitro study, showing that the diffuse hyperplastic type 1a-parathyroids are most suited for autotransplantation. Glands or gland areas without fat-cells (type 1b) or nodules of type 2-glands which can be identified intraoperatively using a stereomagnifier should not be used.