Chromophobe renal cell carcinoma(ChRCC)is the third most common renal cell carcinoma(RCC)subtype,which predominantly occurs in sporadic setting.ChRCCs are considered to originate from the intercalated cell of distal t...Chromophobe renal cell carcinoma(ChRCC)is the third most common renal cell carcinoma(RCC)subtype,which predominantly occurs in sporadic setting.ChRCCs are considered to originate from the intercalated cell of distal tubules with two main morphological variants,classic and eosinophilic.Most ChRCCs carry a favorable clinical outcome.Histology alone is limited in predicting the behavior of ChRCCs that do not have overtly aggressive morphologic findings such as necrosis and sarcomatoid features.Along with positive CD117 expression,classic ChRCCs generally express diffuse and uniform CK7,while eosinophilic variant demonstrates more heterogeneous CK7 expression(rare or patchy).Multiple losses of chromosomes 1,2,6,10,13,17,and 21 are considered to be the genetic hallmarks of classic and eosinophilic ChRCCs,while chromosomal gains are known to be associated with sarcomatoid ChRCCs.TP53 and PTEN are the two most frequently mutated genes in ChRCCs.The major challenge in the differential diagnosis of ChRCCs includes considerations around the eosinophilic variant(of ChRCCs),where it may share overlapping features with oncocytoma or other recent emergent oncocytic tumors.Most eosinophilic ChRCCs share expression of the recently described biomarkers,LINC01187 and FOXI1,with classic ChRCCs,however,a subset of eosinophilic-like ChRCCs with lower biomarker expression have been demonstrated to harbor MTOR gene mutations.Overall,the morphologic features of ChRCCs and genetic profile with combinations of chromosomal losses and gains suggest this tumor entity to represent a distinct,yet heterogeneous group of renal neoplasms.展开更多
Renal cell carcinoma (RCC) is an important contributor to cancer-specific mortality worldwide. Targeted agents that inhibit key subtype-specific signaling pathways have improved survival times and have recently become...Renal cell carcinoma (RCC) is an important contributor to cancer-specific mortality worldwide. Targeted agents that inhibit key subtype-specific signaling pathways have improved survival times and have recently become part of the standard of care for this disease. Accurately diagnosing and classifying RCC on the basis of tumor histology is thus critical. RCC has been traditionally divided into clear-cell and non-clearcell categories, with papillary RCC forming the most common subtype of non-clear-cell RCC. Renal neoplasms with overlapping histologies, such as tumors with mixed clear-cell and papillary features and hybrid renal oncocytic tumors, are increasingly seen in contemporary practice and present a diagnostic challenge with important therapeutic implications. In this review, we discuss the histologic, immunohistochemical, cytogenetic, and clinicopathologic aspects of these differential diagnoses and illustrate how the classification of RCC has evolved to integrate both the tumor's microscopic appearance and its molecular fingerprint.展开更多
文摘Chromophobe renal cell carcinoma(ChRCC)is the third most common renal cell carcinoma(RCC)subtype,which predominantly occurs in sporadic setting.ChRCCs are considered to originate from the intercalated cell of distal tubules with two main morphological variants,classic and eosinophilic.Most ChRCCs carry a favorable clinical outcome.Histology alone is limited in predicting the behavior of ChRCCs that do not have overtly aggressive morphologic findings such as necrosis and sarcomatoid features.Along with positive CD117 expression,classic ChRCCs generally express diffuse and uniform CK7,while eosinophilic variant demonstrates more heterogeneous CK7 expression(rare or patchy).Multiple losses of chromosomes 1,2,6,10,13,17,and 21 are considered to be the genetic hallmarks of classic and eosinophilic ChRCCs,while chromosomal gains are known to be associated with sarcomatoid ChRCCs.TP53 and PTEN are the two most frequently mutated genes in ChRCCs.The major challenge in the differential diagnosis of ChRCCs includes considerations around the eosinophilic variant(of ChRCCs),where it may share overlapping features with oncocytoma or other recent emergent oncocytic tumors.Most eosinophilic ChRCCs share expression of the recently described biomarkers,LINC01187 and FOXI1,with classic ChRCCs,however,a subset of eosinophilic-like ChRCCs with lower biomarker expression have been demonstrated to harbor MTOR gene mutations.Overall,the morphologic features of ChRCCs and genetic profile with combinations of chromosomal losses and gains suggest this tumor entity to represent a distinct,yet heterogeneous group of renal neoplasms.
文摘Renal cell carcinoma (RCC) is an important contributor to cancer-specific mortality worldwide. Targeted agents that inhibit key subtype-specific signaling pathways have improved survival times and have recently become part of the standard of care for this disease. Accurately diagnosing and classifying RCC on the basis of tumor histology is thus critical. RCC has been traditionally divided into clear-cell and non-clearcell categories, with papillary RCC forming the most common subtype of non-clear-cell RCC. Renal neoplasms with overlapping histologies, such as tumors with mixed clear-cell and papillary features and hybrid renal oncocytic tumors, are increasingly seen in contemporary practice and present a diagnostic challenge with important therapeutic implications. In this review, we discuss the histologic, immunohistochemical, cytogenetic, and clinicopathologic aspects of these differential diagnoses and illustrate how the classification of RCC has evolved to integrate both the tumor's microscopic appearance and its molecular fingerprint.
