PATHOMORPHOLOGY OF PARATHYROID AUTOGRAFTS

During the past 16 years we have been treating 211 patients with renal hyperparathyroidism by total parathyroidectomy and immediate autotran splantation. 12 years ago we established the classification of parathy roid tissue into A-, B-, C-, D-regions based on macroscopic and functi onal attributes. Since then we have transplanted only A-regions, which have been selected intraoperatively very under a stereomicroscope. A- regions occur in diffusely and nodular enlarged glands and represent r egular or minimally changed parathyroid tissue according to microscopi c and functional criteria. With this technique we aimed at reduction o f recurrency rates which lay at 12% or 37% in Vienna and Feldkirch res pectively. As a result we can report very low recurrency rates of 0.8% or 3% in Vienna and Feldkirch. Additionally me could document a very close relation between functional morphology of the original gland and the clinical function and morphology of the autograft. In ii patients we could investigate the autografts microscopically. 7 patients had r eceived a conventionally selected autograft, in 4 patients the tissue had been selected under the stereomicroscope. In transplanted A-region s optimal function and unaltered structure could be noted for 2 to 7 y ears postoperatively. Transplanted B-regions, consisting of hypertroph ic dysfunctional cells, caused, recurrencies. The clinical behaviour o f these recurrencies depended on the proliferation tendency of the ori ginal tissue. Very low proliferation (slight PCNA staining) led to enl arged autografts at autopsy. Low proliferation led to clinical progred ience with a rise of plasma-intact PTH to around 1,000 pg/ml over a pe riod of 3 years. These recurrencies could be resolved by removal of 5 to 17 enlarged tissue fragments. High mitotic incidence in the origina l glands led to multiple fulminant recurrencies (plasma-intact PTH ove r 2,500 pg/ml) which could only be stabilized after removal of over 12 0 enlarged and twice as many smallest tissue fragments. When A- and B- regions occurred simultaneously in the autograft an elevated incidence of apoptotic nuclei was found in the A-regions.