縦隔に進展した巨大上皮小体腺腫の1例

A Case of Gigantic Parathyroid Adenoma Extending into the Upper Mediastinum

I．はじめに

　上皮小体腺腫は，原発性上皮小体機能亢進症（Ⅰ°HPTと略）の原因として最も多く認められ，PTH過剰分泌による高カルシウム血症をきたす。唯一の治療法は外科的な摘出であり，摘出により90％以上軽快するといわれている^1）。また，原発性上皮小体機能亢進症における腺腫は，一般的に50～2,000mg程度の大きさのものが多いとされている^2）。

　今回われわれは，縦隔に進展した巨大な上皮小体腺腫を経験したので，文献的考察を加え報告する。

　A 78-year-old woman complaining of a slight fever and general fatigue was found to have hyperparathyroidism with renal function disorder,hypergastolinemia,renal anemia. Plasma level of calcium,and intact-PTH（I-PTH） were elevated to 12.5mg/dl,and 842pg/ml. Cervical CT revealed a gigantic mass under the left lobe of the thyroid gland. ^99mTc-MIBI scintigraphy imaging revealed a hot spot in the upper mediastinum.

　Left parathyroidectomy was performed. The weight of extirpated parathyroid adenoma was 52 g. Immunohistochemical study revealed over-expression of PCNA,and this result demonstrated hyperproliferative condition. Increased serum PTH and calcium became normalized soon after surgery.