Hybrid oncocytic/chromophobe tumor (HOCT) of the kidney arising from a precursor oncocytosis not associated with the Birt-Hogg-Dubé (BHD) syndrome is an unusual and highly interesting neoplasm. Immunohistochemical and molecular findings suggest that HOCT is an entity distinct from both oncocytoma and chromophobe carcinoma. Although uncertainty persists regarding the factors predisposing to the development of HOCT, experimental findings suggest that it may arise due to the effect of toxins or in association with chronic kidney failure. The potential role of prior renal lymphoma in the development of oncocytosis has not hitherto been examined. We present a morphological, immunohistochemical, and molecular analysis of an HOCT arising from renal oncocytosis in conjunction with CLL affecting the kidney. The findings suggest that this tumor belongs to a family of similar neoplasms including oncocytoma, the eosinophilic variant of chromophobe renal-cell carcinoma (CRCC), and low-grade oncocytic tumor, even though these neoplasms may arise from different precursor lesions. HOCT and oncocytosis revealed the same immunohistochemical profile consistent on positivity for epithelial membrane antigen (EMA), cytokeratin 7 (Ck7), E-cadherin, CAM 5.2 and negativity for Pax-8, vimentin, renal-cell carcinoma (RCC) antigen, CD117, racemase, progesterone receptor, and CD10. The Ki-67 proliferation index was #x3c;1%. Molecular analysis of the tumor revealed the AKT3 gene mutation variant, classified as probably pathogenic, together with FOS1 gene amplification and no copy number variations (CNVs). Finally, we present a case of HOCT arising from a nonhereditary renal oncocytosis in conjunction with B lymphoma that raises interesting questions regarding pathogenesis.
Pathobiology

中文翻译：

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与散发性肾嗜酸细胞增多症和慢性 B 细胞淋巴细胞白血病相关的肾脏杂合嗜酸细胞/嫌色细胞肿瘤的形态学和分子研究：淋巴瘤对肾嗜酸细胞增多症的可能贡献

由与 Birt-Hogg-Dubé (BHD) 综合征无关的前体嗜酸细胞增多引起的肾脏混合嗜酸细胞/嫌色细胞肿瘤 (HOCT) 是一种不寻常且非常有趣的肿瘤。免疫组织化学和分子学研究结果表明，HOCT 是一种不同于嗜酸细胞瘤和嫌色细胞癌的实体。尽管关于诱发 HOCT 发展的因素仍然存在不确定性，但实验结果表明它可能是由于毒素的影响或与慢性肾功能衰竭有关。迄今为止尚未检查先前肾淋巴瘤在嗜酸细胞增多症发展中的潜在作用。我们对由肾脏嗜酸细胞增多症和影响肾脏的 CLL 引起的 HOCT 进行形态学、免疫组织化学和分子分析。研究结果表明，这种肿瘤属于一个相似的肿瘤家族，包括嗜酸细胞瘤、嫌色细胞肾细胞癌 (CRCC) 的嗜酸性变体和低级别嗜酸细胞肿瘤，尽管这些肿瘤可能来自不同的前驱病变。HOCT 和嗜酸细胞增多症显示相同的免疫组织化学特征，其与上皮膜抗原 (EMA)、细胞角蛋白 7 (Ck7)、E-钙粘蛋白、CAM 5.2 的阳性和 Pax-8、波形蛋白、肾细胞癌 (RCC) 抗原、CD117 的阴性一致、消旋酶、孕激素受体和 CD10。Ki-67 增殖指数为#x3c;1%。肿瘤的分子分析显示 AKT3 基因突变变体，被归类为可能致病，连同 FOS1 基因扩增和无拷贝数变异 (CNV)。最后，
病理学