色素嫌性腎癌の1例

Abstract

症例は45歳女性で肉眼的血尿を主訴とした.左背部痛も出現し増強したため救急外来を受診した.腹部超音波で左腎に径12cmの巨大腫瘍性病変を認め入院した.腹部CTで左腎の巨大腫瘍による強血尿及び貧血と判断し, 安静及び輸血による保存的治療を施行した.腹部CT, MRI, 血管造影等の所見より悪性腫瘍と診断し, 第8肋骨切除で経腹的根治的左腎摘出術を施行した.病理組織所見から色素嫌性腎癌と診断した.色素嫌性腎癌は1974年にラットにおける実験的な腎腫瘍発生モデルで通常の腎細胞癌とは異なる組織像を呈する腫瘍として報告された.わが国における臨床報告例は現在まで9例の報告例があるにすぎない

We report a case of chromophobe cell renal carcinoma. A 45-year-old woman with a chief complaint of macrohematuria and left backache was introduced to our hospital in October 1998. Abdominal computed tomographic scan (CT) revealed a solitary, solid mass (16 x 14 x 12 cm) at the upper pole of the left kidney. Angiography showed a hypervascular character but irregular neovasculizations were found. We performed a radical nephrectomy with a preoperative diagnosis of malignant renal tumor. The cut surface appearance of the tumor was homogeneous, grey-beige and solid. Light microscopic findings revealed voluminous cells with light, but not clear cytoplasm displaying a fine reticular pattern. Histochemical staining with Hale's colloidal iron stain demonstrated a distinctly positive cytoplasmic reaction. Since the ultrastructural study revealed numerous intracytoplasmic microvesicles, we finally reached the diagnosis of chromophobe cell renal carcinoma. We report our case here with reference to the relevant literature.