<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE article PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Publishing DTD v1.2d1 20170631//EN" "JATS-journalpublishing1.dtd">
      <JournalTitle>Cancer Case Reports</JournalTitle>
      <Volume-Issue>Volume 3; Issue 1</Volume-Issue>
      <ArticleType>Oncology Research</ArticleType>
      <ArticleTitle>Low-Grade Oncocytic Tumor of Kidney: A Distinct Emerging Entity in Renal Oncocytic Neoplasms with Diagnostic Challenge in An Old Female: A Case Report</ArticleTitle>
          <FirstName>Manahil Khan</FirstName>
          <FirstName>Madiha Bilal</FirstName>
      <Abstract>Low grade Oncocytic Tumor (LOT) is an emerging category in renal tumors having oncocytic morphology. It has overlapping features with Renal Oncocytoma and Eosinophilic variant of Chromophobe Renal Cell Carcinoma. LOT typically shows solid nests of cells with oncocytic cytoplasm and uniform round to oval nuclei with a CK7 positive/ CD117 negative immunophenotype. Pathogenesis is not well-understood, however, variations in mTOR pathway related genes have been described. The clinical course is indolent. Here, we present the case a 64-year-old female patient who presented with a solid enhancing mass in right kidney with the clinical impression of Renal cell carcinoma. Right radical nephrectomy was performed, and histologic features were consistent with LOT.</Abstract>
      <Keywords>Low Grade Oncocytic Tumor,Kidney,Emerging</Keywords>
        <Abstract>https://cancercasereports.com/ubijournal-v1copy/journals/abstract.php?article_id=14135&amp;title=Low-Grade Oncocytic Tumor of Kidney: A Distinct Emerging Entity in Renal Oncocytic Neoplasms with Diagnostic Challenge in An Old Female: A Case Report</Abstract>
        <References>Delongchamps NB, Galmiche L, Eiss D, Rouach Y, Vogt B, Timsit MO, Vieillefond A, Mand;eacute;jean A. Hybrid tumour and;#39;oncocytoma-chromophobe renal cell carcinomaand;#39; of the kidney: a report of seven sporadic cases. BJU Int 2009; 103: 1381-1384.&#13;
Guo Q, Liu N, Wang F, Guo Y, Yang B, Cao Z, Wang Y, Wang Y, Zhang W, Huang Q, Zhao W, Liu C, Qu T, Li L, Cao L, Ren D, Meng B, Qi L, Wang C, Cao W. Characterization of a distinct low-grade oncocytic renal tumor (CD117-negative and cytokeratin 7-positive) based on a tertiary oncology center experience: the new evidence from China. Virchows Arch 2021; 478: 449-458.&#13;
Ishikawa N, Kimura N, Yoshida T, Yoshimura I, Nakahara K, Tsuzuki T, Tokunaga O. A Case of Low-Grade Oncocytic Tumor/Chromophobe Renal Cell Carcinoma (Oncocytic Variant) of the Kidney. Case Rep Pathol 2021; 2021: 6684777.&#13;
Kravtsov O, Gupta S, Cheville JC, Sukov WR, Rowsey R, Herrera-Hernandez LP, Lohse CM, Knudson R, Leibovich BC, Jimenez RE. Low-Grade Oncocytic Tumor of Kidney (CK7-Positive, CD117-Negative): Incidence in a single institutional experience with clinicopathological and molecular characteristics. Hum Pathol 2021; 114: 9-18.&#13;
Kryvenko ON, Jorda M, Argani P, Epstein JI. Diagnostic approach to eosinophilic renal neoplasms. Arch Pathol Lab Med 2014; 138: 1531-1541.&#13;
Mikami S, Kuroda N, Nagashima Y, Ohe C, Hayashi H, Mizuno R, Oya M, Kameyama K. Classification of solid renal tumor with oncocytic/eosinophilic cytoplasm: is hybrid oncocytic/chromophobe renal tumor a subtype of oncocytoma, chromophobe renal cell carcinoma, or a distinct tumor entity? Ann Transl Med 2019; 7: S350.&#13;
Morini A, Drossart T, Timsit MO, Sibony M, Vasiliu V, Gimenez-Roqueplo AP, Favier J, Badoual C, Mejean A, Burnichon N, Verkarre V. Low-grade oncocytic renal tumor (LOT): mutations in mTOR pathway genes and low expression of FOXI1. Mod Pathol 2022; 35: 352-360.&#13;
Parkhi M, Chatterjee D, Kumar A, Kumar S. Walking the thin line-Low-grade oncocytic tumor of kidney: An emerging entity. Med J Armed Forces India 2022; 78: 355-359.&#13;
Petersson F, Gatalica Z, Grossmann P, Perez Montiel MD, Alvarado Cabrero I, Bulimbasic S, Swatek A, Straka L, Tichy T, Hora M, Kuroda N, Legendre B, Michal M, Hes O. Sporadic hybrid oncocytic/chromophobe tumor of the kidney: a clinicopathologic, histomorphologic, immunohistochemical, ultrastructural, and molecular cytogenetic study of 14 cases. Virchows Arch 2010; 456: 355-365.&#13;
Ruiz-Cordero R, Rao P, Li L, Qi Y, Atherton D, Peng B, Singh RR, Kim TB, Kawakami F, Routbort MJ, Alouch N, Chow CB, Tang X, Lu W, Brimo F, Matin SF, Wood CG, Tannir NM, Wistuba II, Chen K, Wang J, Medeiros LJ, Karam JA, Tamboli P, Sircar K. Hybrid oncocytic/chromophobe renal tumors are molecularly distinct from oncocytoma and chromophobe renal cell carcinoma. Mod Pathol 2019; 32: 1698-1707.&#13;
Sharma D, Pai T, Prakash G, Desai S, Menon S. Low-Grade Oncocytic Tumor: Report of Two Cases of An Emerging Entity in the Spectrum of Oncocytic Renal Neoplasms. Turk Patoloji Derg 2022; 38: 162-166.&#13;
Siadat F and Trpkov K. ESC, ALK, HOT and LOT: Three Letter Acronyms of Emerging Renal Entities Knocking on the Door of the WHO Classification. Cancers (Basel) 2020; 12: 168.&#13;
Trpkov K and Hes O. New and emerging renal entities: a perspective post-WHO 2016 classification. Histopathology 2019; 74: 31-59&#13;
Trpkov K, Williamson SR, Gao Y, Martinek P, Cheng L, Sangoi AR, Yilmaz A, Wang C, San Miguel Fraile P, Perez Montiel DM, Bulimbasi? S, Rogala J, Hes O. Low-grade oncocytic tumour of kidney (CD117-negative, cytokeratin 7-positive): a distinct entity? Histopathology 2019; 75: 174-184.&#13;
Trpkov K, Williamson SR, Gill AJ, Adeniran AJ, Agaimy A, Alaghehbandan R, Amin MB, Argani P, Chen YB, Cheng L, Epstein JI, Cheville JC, Comperat E, da Cunha IW, Gordetsky JB, Gupta S, He H, Hirsch MS, Humphrey PA, Kapur P, Kojima F, Lopez JI, Maclean F, Magi-Galluzzi C, McKenney JK, Mehra R, Menon S, Netto GJ, Przybycin CG, Rao P, Rao Q, Reuter VE, Saleeb RM, Shah RB, Smith SC, Tickoo S, Tretiakova MS, True L, Verkarre V, Wobker SE, Zhou M, Hes O. Novel, emerging and provisional renal entities: The Genitourinary Pathology Society (GUPS) update on renal neoplasia. Mod Pathol 2021; 34: 1167-1184.&#13;
Williamson SR, Gadde R, Trpkov K, Hirsch MS, Srigley JR, Reuter VE, Cheng L, Kunju LP, Barod R, Rogers CG, Delahunt B, Hes O, Eble JN, Zhou M, McKenney JK, Martignoni G, Fleming S, Grignon DJ, Moch H, Gupta NS. Diagnostic criteria for oncocytic renal neoplasms: a survey of urologic pathologists. Hum Pathol 2017; 63: 149-156.&#13;
Wu A. Oncocytic Renal Neoplasms on Resections and Core Biopsies: Our Approach to This Challenging Differential Diagnosis. Arch Pathol Lab Med 2017; 141: 1336-1341.</References>