Introduction: Chromophobe renal cell carcinoma (chromophobe RCC) is the third major subcategory of renal tumors after clear cell RCC and papillary RCC, accounting for approximately 5% of all RCC subtypes. Other oncocytic neoplasms seen commonly in surgical pathology practice include the eosinophilic variant of chromophobe RCC, renal oncocytoma, and low-grade oncocytic unclassified RCC. Methods: In our recent next-generation sequencing based study, we nominated a lineage-specific novel biomarker LINC01187 (long intergenic non-protein coding RNA 1187) which was found to be enriched in chromophobe RCC. Like KIT (cluster of differentiation 117; CD117), a clinically utilized chromophobe RCC related biomarker, LINC01187 is expressed in intercalated cells of the nephron. In this follow-up study, we performed KIT immunohistochemistry and LINC01187 RNA in situ hybridization (RNA-ISH) on a cohort of chromophobe RCC and other renal neoplasms, characterized the expression patterns, and quantified the expression signals of the two biomarkers in both primary and metastatic settings. Results: LINC01187, in comparison to KIT, exhibits stronger and more uniform expression within tumors while maintaining temporal and spatial consistency. LINC01187 also is devoid of intra-tumoral heterogeneous expression pattern, a phenomenon commonly noted with KIT. Conclusions: LINC01187 expression can augment the currently utilized KIT assay and help facilitate easy microscopic analyses in routine surgical pathology practice.
International journal of surgical pathology. 2022 Oct 16 [Epub ahead of print]
Rahul Mannan, Xiaoming Wang, Pushpinder S Bawa, Yuping Zhang, Stephanie L Skala, Anya K Chinnaiyan, Aniket Dagar, Lisha Wang, Sylvia B Zelenka-Wang, Lisa M McMurry, Nikita Daniel, Xuhong Cao, Ankur R Sangoi, Sounak Gupta, Ulka N Vaishampayan, Khaled S Hafez, Todd M Morgan, Daniel E Spratt, Maria S Tretiakova, Pedram Argani, Arul M Chinnaiyan, Saravana M Dhanasekaran, Rohit Mehra
Department of Pathology, University of Michigan Medical School, Ann Arbor, MI, USA., Michigan Center for Translational Pathology, Ann Arbor, MI, USA., Department of Pathology, 14448El Camino Hospital, Mountain View, CA, USA., Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA., Rogel Cancer Center, Michigan Medicine, Ann Arbor, MI, USA., Department of Radiation Oncology, University Hospitals Seidman Cancer Center, Case Western Reserve University, Cleveland, OH, USA., Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA., Department of Pathology, The Johns Hopkins Hospital, Baltimore, MD, USA.