Turcan Didem, Acikalin Mustafa Fuat, Yilmaz Evrim, Canaz Funda, Arik Deniz
Department of Pathology, Eskişehir Osmangazi University, Faculty of Medicine, Eskişehir, Turkey.
Pathol Res Pract. 2017 Jul;213(7):831-835. doi: 10.1016/j.prp.2017.03.001. Epub 2017 Mar 25.
Nephrogenic adenoma is an uncommon benign lesion that occurs at several sites in urinary tract, from the renal pelvis to urethra, with the highest frequency in urinary bladder. Nephrogenic adenoma displays a broad spectrum of architectural and cytological features. Hence, recognition of its characteristic histopathological features is needed to distinguish this lesion from its mimickers.
A retrospective series of 21 cases of nephrogenic adenoma in 18 patients, which were diagnosed in our department between 2010 and 2016, were analyzed. All histological slides were reviewed by two pathologists and the diagnosis of each case was confirmed. Immunohistochemistry was performed for PAX-8 in all cases. CK7, PAX-2, PSA, p53, p63, GATA-3 and α-methylacyl-CoA racemase (AMACR) were applied in problematic cases.
The most common location of the lesion was urinary bladder (14 patients) followed by renal pelvis (2 patients), ureter (1 patient) and urethra (1 patient). A history of urothelial carcinoma and repeated TUR procedures were observed in 12 patients. There were 2 pediatric patients aged 3 years. Both of them had undergone previous urosurgery because of megaureter in one and bladder exstrophy in the other. Other clinical antecedents included bladder diverticulum (1 patient), cystitis (1 patient) and nephrolithiasis (1 patient). Recurrence of lesion was seen in two patients (once in one case and twice in the other one). The median time to disease recurrence in these patients was 11 months (range, 2-20 months). Histologically, the lesions exhibited various morphological findings, with mixed (15 cases, 71.4%), pure tubular (3 cases, 14.3%), pure papillary (2 cases, 9.5%) and pure flat (1 case, 4.8%) growth patterns. Of the 15 cases with mixed patterns, 8 cases were tubulocystic and flat, 3 cases were tubular and flat, 2 cases were tubular, papillary and flat, 1 case was tubulocystic, papillary and flat, and 1 case was tubular and papillary. Flat pattern was observed in 15 cases (71.4%). It was seen in association with other patterns in 14 cases (mixed morphology) and purely in 1 case. Our findings suggested that the flat pattern is a frequent finding in nephrogenic adenomas. Notably one case in this series showed superficial extension into bladder muscularis propria.
Histologically nephrogenic adenoma may simulate a variety of malignancies. Awareness of characteristic morphologic features of nephrogenic adenoma is needed to diagnose this lesion correctly.
肾源性腺瘤是一种罕见的良性病变，可发生于尿路从肾盂到尿道的多个部位，其中膀胱发生率最高。肾源性腺瘤具有广泛的结构和细胞学特征。因此，需要认识其特征性组织病理学特征以将该病变与其模仿者区分开来。
对2010年至2016年在我科诊断的18例患者中的21例肾源性腺瘤进行回顾性分析。所有组织学切片均由两位病理学家复查，每例诊断均得到确认。所有病例均进行PAX - 8免疫组织化学检测。在疑难病例中应用CK7、PAX - 2、PSA、p53、p63、GATA - 3和α - 甲基酰基辅酶A消旋酶（AMACR）。
病变最常见的部位是膀胱（14例患者），其次是肾盂（2例患者）、输尿管（1例患者）和尿道（1例患者）。12例患者有尿路上皮癌病史及多次经尿道切除术史。有2例3岁的儿科患者。其中1例因巨输尿管、另1例因膀胱外翻曾接受过泌尿外科手术。其他临床病史包括膀胱憩室（1例患者）、膀胱炎（1例患者）和肾结石（1例患者）。2例患者出现病变复发（1例复发1次，另1例复发2次）。这些患者疾病复发的中位时间为11个月（范围2 - 20个月）。组织学上，病变表现出多种形态学表现，有混合性（15例，71.4%）、单纯管状（3例，14.3%）、单纯乳头状（2例，9.5%）和单纯扁平状（1例，4.8%）生长模式。在15例混合模式的病例中，8例为肾小管囊性和平坦状，3例为管状和平坦状，2例为管状、乳头状和平坦状，1例为肾小管囊性、乳头状和平坦状，1例为管状和乳头状。15例（71.4%）观察到扁平状模式。在14例（混合形态）中与其他模式相关联出现，仅1例单纯出现。我们的研究结果表明扁平状模式在肾源性腺瘤中是常见表现。值得注意的是，本系列中有1例显示向膀胱固有肌层浅表浸润。
组织学上肾源性腺瘤可能模拟多种恶性肿瘤。正确诊断该病变需要了解肾源性腺瘤的特征性形态学特征。
