Volmar Keith E, Chan Theresa Y, De Marzo Angelo M, Epstein Jonathan I
Department of Pathology, Johns Hopkins Hospital, Baltimore, MD 21231, USA.
Am J Surg Pathol. 2003 Sep;27(9):1243-52. doi: 10.1097/00000478-200309000-00008.
Florid von Brunn nests may mimic the nested variant of urothelial carcinoma. We examined formalin-fixed, paraffin-embedded tissue from 21 cases of florid von Brunn nests and 11 cases of nested variant of urothelial carcinoma. Morphologic features were recorded in detail. Also, cases were stained with monoclonal antibodies against MIB-1, p53, p27, and cytokeratin 20. Percentage positivity was calculated by counting 300 to 500 cells from each case. Clinical follow-up information was also obtained. Florid von Brunn nests from the bladder were comprised of large nests with regular spacing, and all the nests extended to the same horizontal level at the base of the proliferation. Central lumen formation was often seen within florid von Brunn nests, at times with cystic dilatation, such that there was a spectrum from proliferating von Brunn nests to cystitis glandularis to cystitis cystica. Small, crowded nests with variable spacing and an infiltrative base characterized nested variant of urothelial carcinoma. Four cases showed detrusor muscle invasion on biopsy with an additional case showing detrusor muscle invasion at cystectomy. One additional patient with nested variant of urothelial carcinoma had distant metastases and another had prostatic invasion. Nine of 21 florid von Brunn nests cases were from either the ureter or renal pelvis, whereas all cases of nested variant of urothelial carcinoma arose in the bladder. The ureteral and pelvic florid von Brunn nest cases showed smaller, more variable nests with irregular spacing closely mimicking nested variant of urothelial carcinoma but had a noninfiltrative base and often areas with either a lobular or linear array. Immunohistochemical studies showed nested variant of urothelial carcinoma to have higher MIB-1 expression (8.8% vs. 2.8%, P = 0.01). Nested variant of urothelial carcinoma had nonsignificantly higher p53 positivity (4.2% vs. 1.5%, P = 0.06) and lower p27 positivity (4.7% vs. 7.8%, P = 0.22). Cytokeratin 20 staining was not discriminatory. However, staining with each antibody was widely variable. Wide variation in staining for MIB-1, p53, p27, and cytokeratin 20 was seen in both florid von Brunn nests and nested variant of urothelial carcinoma, such that except for a few cases, a specific cutoff value could not be determined for diagnostic purposes. The findings underscore the importance of morphologic assessment in the distinction of florid von Brunn nests and nested variant of urothelial carcinoma.
弥漫性von Brunn巢可能酷似尿路上皮癌的巢状亚型。我们检查了21例弥漫性von Brunn巢和11例尿路上皮癌巢状亚型的福尔马林固定、石蜡包埋组织。详细记录了形态学特征。此外，对病例进行了抗MIB-1、p53、p27和细胞角蛋白20单克隆抗体染色。通过对每个病例计数300至500个细胞来计算阳性百分比。还获得了临床随访信息。膀胱的弥漫性von Brunn巢由间距规则的大巢组成，所有巢在增殖底部延伸至同一水平。弥漫性von Brunn巢内常可见中央腔形成，有时伴有囊性扩张，从而形成从增生性von Brunn巢到腺性膀胱炎再到囊性膀胱炎的一系列病变。尿路上皮癌巢状亚型的特征是小而密集的巢，间距可变，底部呈浸润性。4例活检显示逼尿肌侵犯，另有1例在膀胱切除术中显示逼尿肌侵犯。1例尿路上皮癌巢状亚型患者有远处转移，另1例有前列腺侵犯。21例弥漫性von Brunn巢病例中有9例来自输尿管或肾盂，而所有尿路上皮癌巢状亚型病例均发生于膀胱。输尿管和肾盂的弥漫性von Brunn巢病例显示巢较小、更具变异性，间距不规则，酷似尿路上皮癌巢状亚型，但底部无浸润，且常有小叶状或线性排列区域。免疫组化研究显示，尿路上皮癌巢状亚型的MIB-1表达较高（8.8%对2.8%，P = 0.01）。尿路上皮癌巢状亚型的p53阳性率略高（4.2%对1.5%，P = 0.06），p27阳性率较低（4.7%对7.8%，P = 0.22）。细胞角蛋白20染色无鉴别意义。然而，每种抗体的染色差异很大。弥漫性von Brunn巢和尿路上皮癌巢状亚型中MIB-1、p53、p27和细胞角蛋白20的染色均有很大差异，因此除少数病例外，无法确定用于诊断目的的特定临界值。这些发现强调了形态学评估在区分弥漫性von Brunn巢和尿路上皮癌巢状亚型中的重要性。
