Departments of *Pathology †Human Genetics §Urology, McGill University ‡McGill University and Genome Quebec Innovation Centre ∥Pathologie et Biologie Cellulaire, Université de Montréal, QC, Canada.
Am J Surg Pathol. 2014 Jul;38(7):887-94. doi: 10.1097/PAS.0000000000000247.
Papillary renal cell carcinomas (pRCC) are classically divided into type 1 and 2 tumors. However, many cases do not fulfill all the criteria for either type. We describe the clinical, morphologic, and immunohistochemical (IHC) features of 132 pRCCs to better characterize the frequency and nature of tumors with overlapping features. Cases were reviewed and classified; IHC evaluation of CK7, EMA, TopoIIα, napsin A, and AMACR was performed on 95 cases. The frequencies of type 1, type 2, and "overlapping" pRCC were 25%, 28%, and 47%, respectively. The 2 categories of "overlapping" tumors were: (1) cases with bland cuboidal cells but no basophilic cytoplasm (type A); and (2) cases with predominantly type 1 histology admixed with areas showing prominent nucleoli (type B). The pathologic stage of "overlapping" cases showed concordance with type 1 tumors. Using the 2 discriminatory markers (CK7, EMA), "type A" cases were similar to type 1. Although the high-nuclear grade areas of "type B" tumors showed some staining differences from their low-nuclear grade counterpart, their IHC profile was closer to type 1. Single nucleotide polymorphism array results, although preliminary and restricted to only 9 cases (3 with overlapping features), also seemed to confirm those findings. In conclusion, we demonstrate that variations in cytoplasmic quality and/or presence of high-grade nuclei in tumors otherwise displaying features of type 1 pRCCs are similar in stage and IHC profile those with classic type 1 histology, suggesting that their spectrum might be wider than originally described.
乳头状肾细胞癌 (pRCC) 经典地分为 1 型和 2 型肿瘤。然而，许多病例不符合任一型的所有标准。我们描述了 132 例 pRCC 的临床、形态学和免疫组织化学 (IHC) 特征，以更好地描述具有重叠特征的肿瘤的频率和性质。对病例进行了复习和分类；对 95 例病例进行了 CK7、EMA、TopoIIα、napsin A 和 AMACR 的 IHC 评估。1 型、2 型和“重叠”pRCC 的频率分别为 25%、28%和 47%。2 类“重叠”肿瘤为：(1) 具有温和的立方细胞但无嗜碱性细胞质的病例 (A 型)；和 (2) 主要为 1 型组织学，伴有明显核仁的区域的病例 (B 型)。“重叠”病例的病理分期与 1 型肿瘤一致。使用 2 种鉴别性标志物 (CK7、EMA)，“A 型”病例与 1 型相似。尽管“B 型”肿瘤的高核级区域与其低核级区域相比存在一些染色差异，但它们的 IHC 谱更接近 1 型。尽管初步且仅限制在 9 例（3 例具有重叠特征），但单核苷酸多态性阵列结果似乎也证实了这些发现。总之，我们证明，在其他方面表现为 1 型 pRCC 特征的肿瘤中细胞质质量的变化和/或存在高级核，在分期和 IHC 特征方面与具有经典 1 型组织学的肿瘤相似，表明其谱可能比最初描述的更广泛。
