1.Department of Pathology, Brigham and Women's Hospital & Harvard Medical School, Boston, MA 02115, USA2.Brigham and Women's Hospital , Harvard Medical School, Boston , MA (USA)
Clear cell (tubulo)papillary renal cell carcinoma (CCTPRCC) is a recently-recognized tumour that shares morphologic features with both clear cell renal cell carcinoma (CCRCC) and papillary renal cell carcinoma (PRCC) but behaves in a more indolent fashion.
4% of renal cell carcinoma, historically most often mistaken for CCRCC. First described in the setting of end stage renal disease, but now known to be most frequently recognized and encountered in a sporadic setting
Patients are usually asymptomatic as these tumors are often small and incidentally found.
Well-defined and well encapsulated small tumor with frequent cystic formation; usually solitary and unilateral, but multifocality and bilaterally have been reported 1,2,3.
Characteristic histology includes: branched tubular structures, straight nuclear alignment (picket fence nuclei) above the basement membrane, variable papillary structures protruding into cystic spaces, and low nuclear grade (Fig.1A); an associated fibrous capsule and/or fibromuscular stroma may be present in a subset of cases
Strong, diffuse positivity for cytokeratin (CK) 7, and absence of racemase (AMACR) and a cup-like staining pattern for carbonic anhydrase (CA) IX, which has been thought to be unique to this entity (Fig.1B)
Fig 1 : Clear cell tubulopapillary renal cell carcinoma (CCTPRCC) is a low grade neoplasm characterized by tubulopapillary architecture (a predominant tubular architecture is shown in the left image), a u2018picket fence-likeu2019 arrangement of the nuclei, and clear cytoplasm (A). Carbonic anhydrase IX (CA9) expression (right) shows a characteristic u2018cup-likeu2019 staining pattern (B).
• Combine FISH data, NGS data and virtual karyotyping by SNP array demonstrated minimal genetic variability in this tumor, with normal status of VHL gene (methylation, LOH 3p, mutations) 5,6,7,8.
• Some somatic mutaciones, as MET, PTEN, ERBB4, and STK11, have been identified , and RNA profiling revealed overexpression of miR-200 family, distinct from those in other renal tumors 2
Indolent tumor with good clinical outcomes, without any recurrences, metastases, or lymph node involvement 4.
Michelle S. Hirsch ; Paola Dal Cin
Clear cell (tubulo)papillary renal cell carcinoma
Atlas Genet Cytogenet Oncol Haematol. 2021-10-29
Online version: http://atlasgeneticsoncology.org/solid-tumor/208924/clear-cell-(tubulo)papillary-renal-cell-carcinoma