Inoue Daisuke, Oura Shoji
Department of Surgery, Kishiwada Tokushukai Hospital, Kishiwada-city, Osaka, 596-8522 Japan.
Radiol Case Rep. 2023 Jul 27;18(10):3504-3508. doi: 10.1016/j.radcr.2023.07.006. eCollection 2023 Oct.
An 82-year-old man developed a hypervascular renal tumor, 2 cm in size, and multiple liver tumors. Liver tumors had obscured tumor margins on ultrasonography. Positron emission tomography/computed tomography (PET/CT) showed no areas of avid radiotracer uptake in the liver. Routine pathological examination failed to demonstrate tumor cells in 9 tissue samples obtained from repeated core needle biopsies. Even a frozen section of the liver segment 8 tumor further failed to prove malignant cells, and an additive frozen section of the liver section 2 tumor finally proved atypical cells growing in tubular and solid fashions with eosinophilic cytoplasm. Tumors showed expansive growth patterns, were in direct contact with normal liver cells, had abundant micro-vessels, had only sparse hyalinized septa, and had no pale cells. Immunostaining revealed the tumor cells to be positive for CD10, CD117, and E-cadherin and negative for CK7, and PAX8, leading to the diagnosis of metastatic chromophobe renal cell carcinoma (chRCC) in the liver. Arginase-1 immunostaining clearly demarcated the boundary between the chRCC cells and normal hepatic cells. Diagnostic physicians should note that chRCCs are of low-grade malignancy despite their abundant intra-tumoral blood flow and can often pose imaging and pathologic diagnostic difficulties.
一名82岁男性出现了一个大小为2厘米的富血管性肾肿瘤以及多个肝肿瘤。超声检查显示肝肿瘤使肿瘤边界模糊不清。正电子发射断层扫描/计算机断层扫描（PET/CT）显示肝脏中没有放射性示踪剂摄取增加的区域。对重复进行的粗针活检获取的9份组织样本进行常规病理检查，均未发现肿瘤细胞。即使对肝8段肿瘤进行冰冻切片检查，也未能进一步证实存在恶性细胞，而对肝2段肿瘤进行的补充冰冻切片最终证实存在以管状和实性方式生长的非典型细胞，其细胞质呈嗜酸性。肿瘤呈膨胀性生长模式，与正常肝细胞直接接触，微血管丰富，仅有稀疏的玻璃样变间隔，且无苍白细胞。免疫组化显示肿瘤细胞CD10、CD117和E-钙黏蛋白呈阳性，CK7和PAX8呈阴性，从而诊断为肝脏转移性嫌色肾细胞癌（chRCC）。精氨酸酶-1免疫组化清晰地划分了chRCC细胞与正常肝细胞之间的边界。诊断医师应注意，尽管chRCC肿瘤内血流丰富，但其恶性程度较低，且常常会给影像学和病理诊断带来困难。
