Update on Selected Oncocytic Renal Cell Tumors

Abstract

Renal cell tumors with eosinophilic/oncocytic cells include oncocytic papillary renal neoplasm with reverse polarity, oncocytoma, chromophobe renal cell carcinoma, hybrid oncocytic/chromophobe renal tumor, succinate dehydrogenasedeficient renal cell carcinoma, translocation-associated renal cell carcinoma, etc. Recently, several novel and evolving oncocytic renal tumors have been identified, such as eosinophilic solid and cystic renal cell carcinoma, eosinophilic vacuolated tumor, and low-grade oncocytic tumor. In addition, fumarate hydratase-deficient renal cell carcinoma occasionally presents with a low-grade oncocytic morphology. Although these entities demonstrate some overlapping morphological features with oncocytoma and chromophobe renal cell carcinoma, they do have some unique morphological, immunohistochemical, and molecular profiles. In this review, we present an update on selected oncocytic renal cell tumors (eosinophilic vacuolated tumor, low-grade oncocytic tumor, eosinophilic solid and cystic renal cell carcinoma, low-grade fumarate hydratase-deficient renal cell carcinoma, and hybrid oncocytic/chromophobe renal tumor) and discuss their morphologies, immunohistochemical profiles, molecular genetic profiles, and biological behaviors.

Updates from the 2022 WHO Classification of Kidney Epithelial Tumors

“…"Hybrid oncocytic/chromophobe tumor (HOCT)" has been suggested as the name for eosinophilic/oncocytic tumor with borderline or mixed morphological features of oncocytoma and ChRCC or "ambiguous architectural or cytological features" that cannot be ascribed to either oncocytoma or ChRCC. 18 These tumors can occur in a hereditary setting, such as Birt-Hogg-Dube syndrome, or sporadically (Fig. 2a).…”

Advances, Timely Topics, and Updates in Genitourinary Pathology

“…Hui-Zhi Zhang, Ming Zhao, and Dengfeng Cao provide an update on selected renal cell tumors with oncocytic features. 2 The five renal tumors selected for in-depth analysis and discussion are eosinophilic solid and cystic renal cell carcinoma (RCC), eosinophilic vacuolated tumor, low-grade oncocytic tumor, low-grade fumarate hydratase-deficient RCC, and hybrid oncocytic/chromophobe renal tumor. According to the 2022 WHO classification, eosinophilic solid and cystic RCC and fumarate hydratase-deficient RCC are distinct entities, while eosinophilic vacuolated tumors, low-grade oncocytic tumors, and hybrid oncocytic/ chromophobe renal tumors are found in the section describing "Other Oncocytic Tumors of the Kidney," 3 where eosinophilic vacuolated tumors and low-grade oncocytic tumors are considered to be emerging entities.…”

“…According to the 2022 WHO classification, eosinophilic solid and cystic RCC and fumarate hydratase-deficient RCC are distinct entities, while eosinophilic vacuolated tumors, low-grade oncocytic tumors, and hybrid oncocytic/ chromophobe renal tumors are found in the section describing "Other Oncocytic Tumors of the Kidney," 3 where eosinophilic vacuolated tumors and low-grade oncocytic tumors are considered to be emerging entities. Dr. Zhang et al 2 present a table that nicely summarizes the critical clinical features, morphology, immunohistochemistry, molecular features, and prognosis of the five tumors. In addition, the figures convey essential diagnostic attributes.…”