Gu Xin, Cheng Minyu, Herrera Guillermo A
a Department of Pathology , Louisianan State University Health Science Center-Shreveport , Shreveport , LA , USA.
Ultrastruct Pathol. 2018 Jan-Feb;42(1):18-22. doi: 10.1080/01913123.2017.1388321. Epub 2017 Dec 1.
Primary carcinoid tumor of the kidney is uncommon. Only limited morphologic studies have been reported in the literature. In general, renal carcinoid tumor reveals typical morphological features as present in carcinoid tumors in the other organs, i.e. growing as trabeculae intermixed with nests of monotonous cuboidal cells that show "salt and pepper" nuclear appearance. As reported in other organs, different morphological expressions may also present in renal carcinoid tumors, such as papillary, pseudoglandular or solid growth patterns and clear/eosinophilic cytoplasmic changes. These morphological variations may mimic other benign and malignant primary neoplasms in the kidney. Therefore, in some cases, ancillary studies are necessary or even crucial to differentiate carcinoid tumors from other primary renal neoplasms. Herewith, we report two primary renal carcinoid tumors with long follow-up, one showed typical morphological features of carcinoid tumor, and the second one revealed some uncommon histological findings. To differentiate these carcinoid tumors from other primary renal neoplasms and confirm neuroendocrine differentiation, immunohistochemical studies are valuable. In case 2 immunohistochemical stain results were not definitive and electron microscopy was performed confirming the diagnosis of carcinoid tumor.
原发性肾类癌肿瘤并不常见。文献中仅报道了有限的形态学研究。一般来说，肾类癌肿瘤呈现出与其他器官类癌肿瘤相同的典型形态学特征，即呈小梁状生长，夹杂着巢状排列的形态单一的立方体细胞，细胞核呈“椒盐”样外观。正如在其他器官中所报道的那样，肾类癌肿瘤也可能呈现不同的形态学表现，如乳头状、假腺管样或实性生长模式以及透明/嗜酸性细胞质改变。这些形态学变异可能会与肾脏的其他良性和恶性原发性肿瘤相混淆。因此，在某些情况下，辅助检查对于将类癌肿瘤与其他原发性肾肿瘤区分开来是必要的，甚至是至关重要的。在此，我们报告两例经过长期随访的原发性肾类癌肿瘤，其中一例表现出类癌肿瘤的典型形态学特征，另一例则显示出一些不常见的组织学表现。为了将这些类癌肿瘤与其他原发性肾肿瘤区分开来并确认神经内分泌分化，免疫组织化学研究具有重要价值。在病例2中，免疫组织化学染色结果不明确，因此进行了电子显微镜检查以确诊类癌肿瘤。
