Khayyata Said, Grignon David J, Aulicino Michael R, Al-Abbadi Mousa A
Department of Pathology, Harper University Hospital, Wayne State University/Detroit Medical Center, Detroit, Michigan 48201, USA.
Acta Cytol. 2007 May-Jun;51(3):464-7. doi: 10.1159/000325769.
Metanephric adenoma (MA) is a rare benign renal neoplasm that can occur at any age, whereas, Wilms' tumor (WT) is the most common malignant renal neoplasm in children and is occasionally seen in adults.
In case 1, a 26-year-old male had a left renal mass. Fine needle aspiration (FNA) showed 3-dimensional sheets of cells with nuclear overlapping, molding, irregular nuclear membrane and distinct nucleoli. Frequent mitotic figures could be seen. The cytologic differential diagnosis included Wilms' tumor, neuroectodermal tumor and metanephric adenoma. Nephrectomy revealed Wilms' tumor. In case 2, a 24-year-old female presented with erythrocytosis and a right renal mass. FNA showed small, uniform cells with smooth nuclear membrane, fine chromatin and inconspicuous nucleoli. A diagnosis of metanephric adenoma was made and confirmed on nephrectomy.
Differentiating MA from WT based on cytologic features on FNA biopsy prior to surgical resection can he difficult.
后肾腺瘤（MA）是一种罕见的良性肾肿瘤，可发生于任何年龄，而肾母细胞瘤（WT）是儿童最常见的恶性肾肿瘤，偶尔也可见于成人。
病例1，一名26岁男性有左肾肿块。细针穿刺抽吸（FNA）显示细胞呈三维片状，有核重叠、核塑形、核膜不规则及明显核仁。可见频繁的有丝分裂象。细胞学鉴别诊断包括肾母细胞瘤、神经外胚层肿瘤和后肾腺瘤。肾切除术显示为肾母细胞瘤。病例2，一名24岁女性出现红细胞增多症及右肾肿块。FNA显示细胞小而均匀，核膜光滑，染色质细腻，核仁不明显。诊断为后肾腺瘤，并经肾切除术证实。
在手术切除前，基于FNA活检的细胞学特征将MA与WT区分开来可能很困难。
