腎Oncocytoma

RENAL ONCOCYTOMA

　腎腫瘍の多くは悪性腫瘍であるが，最近，On-cocytomaと呼ばれる予後良好な腎腫瘍が発表されてきた^1〜5）。Oncocytomaとは^6）エオジン好性の細胞質を有し，多数の糸粒体が存在している細胞からなる腫瘍である。腎には良性腫瘍として皮質腺腫が存在するが，腎Oncocytomaはそれとは明らかに異なり，組織学的にはむしろ顆粒細胞癌に近い^1）。最近，われわれは2例の腎Oncocytomaを経験し，1例はすでに発表している⁷。観察期間が短いため予後に関しての結論を出すことはできないが，自験例の臨床像，組織像を記載し，文献的考察を試みた。

Oncocytoma was designated as a tumor to be composed of oncocytes with an acidophilic cytoplasm containing of abundant mitochondria. A case of renal oncocytoma was presented herein. A 73 year-old male was complaining of right abdominal mass. Right nephrectomy was performed after the diagnosis was made by the laboratory and X-ray examinations. Histological and electron microscopic findings were consistent with renal oncocytoma as formerly shown in the literatures.

Based on the 31 cases already presented in the paper, clinical and pathological findings of the renal oncocytoma were reviewed.