Department of Urology, Hirosaki University Graduate School of Medicine, 5 Zaifucho, Hirosaki 036-8562, Japan.
BMC Urol. 2013 Dec 13;13:72. doi: 10.1186/1471-2490-13-72.
Chromophobe renal cell carcinoma is the third most common form of adult renal epithelial neoplasm. A sarcomatoid component occurs in approximately 8% of all chromophobe renal cell carcinoma cases, while metaplastic bone formation is extremely rare.
An abdominal computed tomography scan revealed a hypovascular tumor with focal calcification, measuring 2.5 × 2.3 cm, in the upper pole of the right kidney. The tumor was clinically diagnosed as a right renal cell carcinoma that showed signs of calcification, and a laparoscopic right radical nephrectomy was performed. The cut surface of the tumor was beige in color and indicated that the tumor was an extensively ossified mass. Histological analysis revealed three distinct morphological components of the tumor. The chromophobe renal cell carcinoma consisted of compact epithelial cells arranged in a nested pattern, and these were mixed with extensive areas of sarcomatoid spindle cells with marked nuclear pleomorphism and brisk mitotic activity. The tumor also contained multiple foci of metaplastic ossification.
Chromophobe renal cell carcinoma with concomitant osseous metaplasia and sarcomatoid transformation is a very rare occurrence.
嗜铬细胞瘤是成人肾上皮性肿瘤中第三常见的类型。约 8%的嗜铬细胞瘤病例中存在梭形细胞肉瘤样成分，而骨形成的化生则极为罕见。
腹部 CT 扫描显示右肾上极有一个 2.5×2.3cm 的低血供肿瘤，伴有局灶性钙化。肿瘤临床诊断为右肾细胞癌伴钙化，行腹腔镜右肾根治性切除术。肿瘤切面呈米色，表明肿瘤为广泛骨化的肿块。组织学分析显示肿瘤有三个不同的形态学成分。嗜铬细胞瘤由排列呈巢状的密集上皮细胞组成，其中混合有广泛的梭形肉瘤样细胞区，具有明显的核多形性和活跃的有丝分裂活动。肿瘤还包含多个骨化生灶。
同时伴有骨化生和梭形细胞肉瘤样转化的嗜铬细胞瘤非常罕见。
