Tickoo S K, Amin M B, Zarbo R J
Department of Pathology, Henry Ford Hospital, Detroit, Michigan 48202, USA.
Am J Surg Pathol. 1998 Apr;22(4):419-24. doi: 10.1097/00000478-199804000-00005.
Positive staining with Hale's colloidal iron stain, or modifications thereof, is considered a diagnostic feature for chromophobe renal cell carcinoma and has been used as a discriminatory feature to differentiate it from other renal tumors. We studied colloidal iron staining in 62 cases encompassing a wide histologic spectrum of renal neoplasms (14 chromophobe renal cell carcinomas, 19 renal oncocytomas, 11 each of granular variants and conventional clear cell renal cell carcinomas, and 7 eosinophilic variants of papillary renal cell carcinoma) to investigate the specificity of the stain for chromophobe renal cell carcinoma. In cases of chromophobe renal cell carcinoma, sections from two different areas were stained to ascertain whether there was any spatial variation in staining. Influence of staining techniques on the results also was investigated by staining each case of chromophobe renal cell carcinoma using two different methods: the traditional Hale's and a modified Mowry's technique, which treats sections with 3% acetic acid before adding the colloidal iron. Our results show that positive staining with colloidal iron stain is not limited to chromophobe renal cell carcinoma, however, a diffuse and strong, reticular staining pattern was observed only in cases of chromophobe renal cell carcinoma (14 of 14). The staining patterns were less consistent in all other renal neoplasms and differed from the reaction observed in chromophobe renal cell carcinoma. Most renal oncocytomas (16 of 19) had focal and weak, fine dustlike positivity, and all clear cell carcinomas showed focal, coarse, dropletlike positive staining (22 of 22), in addition to a focal, coarse, bubbly pattern in 5 of 11 clear cell subtypes. Although all seven cases of the eosinophilic variant of papillary renal cell carcinoma showed strong, coarse, dropletlike staining, most of the positivity was coincident with the Perl's (prussian blue) reaction, indicating that the staining was due to hemosiderin, which is frequently present in this histologic subtype of renal cell carcinoma. Staining intensity did not vary considerably among different areas of chromophobe renal cell carcinoma, but the modified Mowry's method yielded brighter and sharper reticular staining, as compared with the Hale's method. Our results show that in the appropriate morphologic context diffuse and strong reticular positivity using the modified Mowry's colloidal iron stain method is highly characteristic for chromophobe renal cell carcinoma. Treatment of sections with 3% acetic acid before adding the colloidal iron gives technically superior staining results.
用黑尔氏胶态铁染色法或其改良方法进行阳性染色，被认为是嫌色性肾细胞癌的一项诊断特征，并已被用作将其与其他肾肿瘤区分开来的鉴别特征。我们研究了62例涵盖广泛组织学类型的肾肿瘤（14例嫌色性肾细胞癌、19例肾嗜酸细胞瘤、11例颗粒型和传统透明细胞肾细胞癌各11例，以及7例乳头状肾细胞癌嗜酸细胞变型）中的胶态铁染色，以研究该染色对嫌色性肾细胞癌的特异性。对于嫌色性肾细胞癌病例，取自两个不同区域的切片进行染色，以确定染色是否存在空间差异。还通过使用两种不同方法对每例嫌色性肾细胞癌进行染色，来研究染色技术对结果的影响：传统的黑尔氏方法和改良的莫里氏方法，改良的莫里氏方法在添加胶态铁之前先用3%乙酸处理切片。我们的结果表明，胶态铁染色阳性并不局限于嫌色性肾细胞癌，然而，仅在嫌色性肾细胞癌病例（14例中的14例）中观察到弥漫性、强的网状染色模式。在所有其他肾肿瘤中，染色模式不太一致，且与嫌色性肾细胞癌中观察到的反应不同。大多数肾嗜酸细胞瘤（19例中的16例）有局灶性、弱阳性、细尘状阳性，所有透明细胞癌均显示局灶性、粗颗粒状、滴状阳性染色（22例中的22例），此外，11例透明细胞亚型中有5例有局灶性、粗颗粒状泡状模式。尽管乳头状肾细胞癌嗜酸细胞变型的所有7例均显示强的、粗颗粒状、滴状染色，但大多数阳性与珀耳斯（普鲁士蓝）反应一致，表明该染色是由于含铁血黄素所致，含铁血黄素在这种肾细胞癌组织学亚型中经常存在。嫌色性肾细胞癌不同区域之间的染色强度变化不大，但与黑尔氏方法相比，改良的莫里氏方法产生的网状染色更亮、更清晰。我们的结果表明，在适当的形态学背景下，使用改良的莫里氏胶态铁染色法出现弥漫性、强的网状阳性对嫌色性肾细胞癌具有高度特征性。在添加胶态铁之前先用3%乙酸处理切片可获得技术上更好的染色结果。
