The category of "oncocytic renal tumors'' includes well-recognized entities, such as renal oncocytoma (RO) and eosinophilic variant of chromophobe renal cell carcinoma (eo-ChRCC), as well as a group of "gray zone" oncocytic tumors, with overlapping features between RO and eo-ChRCC that create ongoing diagnostic and classification problems. These types of renal tumors were designated in the past as "hybrid oncocytoma-chromophobe tumors". In a recent update, the Genitourinary Pathology Society (GUPS) proposed the term "oncocytic renal neoplasm of low malignant potential, not further classified", for such solitary and sporadic, somewhat heterogeneous, but relatively indolent tumors, with equivocal RO/eo-ChRCC features. GUPS also proposed that the term "hybrid oncocytic tumor" be reserved for tumors found in a hereditary setting, typically arising as bilateral and multifocal ones (as in Birt-Hogg-Dubé syndrome). More recent developments in the "gray zone" of oncocytic renal tumors revealed that potentially distinct entities may have been "hidden" in this group. Recent studies distinguished two new entities: "Eosinophilic Vacuolated Tumor" (EVT) and "Low-grade Oncocytic Tumor" (LOT). The rapidly accumulated evidence on EVT and LOT has validated the initial findings and has expanded the knowledge on these entities. Both are uniformly benign and are typically found in a sporadic setting, but rarely can be found in patients with tuberous sclerosis complex. Both have readily distinguishable morphologic and immunohistochemical features that separate them from similar renal tumors, without a need for detailed molecular studies. These tumors very frequently harbor TSC/MTOR mutations that are however neither specific nor restricted to these two entities. In this review, we outline a proposal for a working framework on how to classify such low-grade oncocytic renal tumors. We believe that such framework will facilitate their handling in practice and will stimulate further discussions and studies to fully elucidate their spectrum.

• MeSH
• karcinom z renálních buněk * genetika   MeSH
• ledviny patologie   MeSH
• lidé MeSH
• nádorové biomarkery genetika   MeSH
• nádory ledvin * genetika   MeSH
• oxyfilní adenom * patologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• nádorové biomarkery MeSH

A number of recently described renal tumor entities share an eosinophilic/oncocytic morphology, somewhat solid architectural growth pattern, and tendency to present as low-stage tumors. The vast majority of such tumors follow a non-aggressive clinical behavior. In this review, we discuss the morphological, immunohistochemical, and molecular genetic profiles of the three most recent novel/emerging renal entities associated with TSC/mTOR pathway mutations. These are eosinophilic solid and cystic renal cell carcinoma, eosinophilic vacuolated tumors, and low-grade oncocytic tumors, which belong to a heterogeneous group of renal tumors, demonstrating mostly solid architecture, eosinophilic/oncocytic cytoplasm, and overlapping morphological and immunohistochemical features between renal oncocytoma and chromophobe renal cell carcinoma. All three tumors also share a molecular genetic background with mutations in the mTORC1 pathway (TSC1/TSC2/mTOR/RHEB). Despite the common genetic background, it appears that the tumors with TSC/mTOR mutations represent a diverse group of distinct renal neoplasms.

• Klíčová slova
• ESC, EVT, LOT, chromophobe, eosinophilic, kidney, mTOR, oncocytic, renal, tumor,
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

(1) Background: There are limited data concerning inter-tumoral and inter-metastatic heterogeneity in clear cell renal cell carcinoma (CCRCC). The aim of our study was to review published data and to examine mutation profile variability in primary and multiple pulmonary metastases (PMs) in our cohort of four patients with metastatic CCRCC. (2) Methods: Four patients were enrolled in this study. The clinical characteristics, types of surgeries, histopathologic results, immunohistochemical and genetic evaluations of corresponding primary tumor and PMs, and follow-up data were recorded. (3) Results: In our series, the most commonly mutated genes were those in the canonically dysregulated VHL pathway, which were detected in both primary tumors and corresponding metastasis. There were genetic profile differences between primary and metastatic tumors, as well as among particular metastases in one patient. (4) Conclusions: CCRCC shows heterogeneity between the primary tumor and its metastasis. Such mutational changes may be responsible for suboptimal treatment outcomes in targeted therapy settings.

• Klíčová slova
• clear cell renal cell carcinoma, inter-metastatic heterogeneity, inter-tumoral heterogeneity, intra-tumoral heterogeneity,
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH