Adenocarcinoma, Clear Cell ; metabolism ; pathology ; surgery ; Adult ; Carcinoma ; metabolism ; pathology ; Carcinoma, Mucoepidermoid ; metabolism ; pathology ; Carcinoma, Renal Cell ; metabolism ; pathology ; secondary ; Diagnosis, Differential ; Humans ; Keratins ; metabolism ; Male ; Nasal Cavity ; Nose Neoplasms ; metabolism ; pathology ; surgery ; S100 Proteins ; metabolism

Adenocarcinoma, Follicular ; Adult ; Carcinoid Tumor ; metabolism ; pathology ; Carcinoma, Renal Cell ; metabolism ; pathology ; surgery ; Diagnosis, Differential ; Female ; Humans ; Keratin-7 ; metabolism ; Kidney Neoplasms ; metabolism ; pathology ; surgery ; Mucin-1 ; metabolism

Adenocarcinoma, Follicular ; genetics ; metabolism ; pathology ; Carcinoma, Papillary ; genetics ; metabolism ; pathology ; Carcinoma, Renal Cell ; genetics ; metabolism ; pathology ; Diagnosis, Differential ; Humans ; Immunohistochemistry ; Kidney Diseases, Cystic ; genetics ; metabolism ; pathology ; Kidney Neoplasms ; genetics ; metabolism ; pathology ; Thyroid Neoplasms ; genetics ; metabolism ; pathology ; Translocation, Genetic

Carcinoma, Medullary ; pathology ; Carcinoma, Renal Cell ; diagnosis ; metabolism ; pathology ; radiotherapy ; surgery ; Diagnosis, Differential ; Humans ; Keratins ; metabolism ; Kidney Neoplasms ; diagnosis ; metabolism ; pathology ; radiotherapy ; surgery ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Neoplasms, Squamous Cell ; pathology ; Nephrectomy ; Radiotherapy, Adjuvant

OBJECTIVETo investigate the clinicopathological characteristics and the diagnosis of multilocular cystic renal cell carcinoma (MCRCC).

METHODSThe clinicopathological data of 19 MCRCC cases were collected and immunohistochemical staining assays were carried out. Forty-six cases of other cystic kidney lesions within the same period were collected as controls, including extensively cystic clear cell RCC (12 cases), clear cell tubulopapillary renal cell carcinoma (6 cases), tubulocystic carcinoma (2 cases), simple cortical cysts (22 cases), multilocular cystic nephroma (1 cases) and multicystic kidney (3 cases).

RESULTSThe patients included 14 males and 5 females. The ages ranged from 31 to 66 years (median age = 50 years). Most of the MCRCC cases were detected incidentally in physical examination, occasionally accompanied with hematuria, back pain or other symptoms. The follow-up period of 17 patients ranged from 6 to 170 months. All patients were alive without evidence of tumor recurrence or metastasis. Pathological findings showed that macroscopically, tumor size ranges from 1.5 to 7.0 cm in the maximum diameter, generally a entirely of various sized. The cysts contain serous, hemorrhagic or turbid fluid. Solid areas or substantially discernible mural nodules were absent; histologicallly, single layer of cuboidal and flattened epithelial tumor cells were lined in the cysts, described as clear cytoplasm, small nuclear, no nucleoli and low Fuhrman nuclear grade (I or II). Multilayer tumor cells could be observed in a few cysts, with granular cytoplasm and small intracystic papillae formed. The clear tumor cell clusters, similar as cystic lined tumor cells, were seen within pathological fibrous in almost all cases, and significant myofibroblastic proliferation was found in 14 cases. Immunohistochemically, the cysts lined epithelial cells and the clear tumor cell clusters were positive for epithelium markers, including CKpan(19/19), EMA(16/19) and CK7 (15/19); higher percentage of CAIX (17/19) and PAX8(15/19) than control groups, but lower percentage of CD10 (7/19), RCC (6/19) and AMACR(2/19); and all were negative for 34βE12, CD117 and CD68.

CONCLUSIONSMultilocular cysts, clear cells clusters of low Fuhrman grade within fibrous septa and capillary vessel proliferation under epithelium are important features of MCRCC. The united using of CAIX, CK7, CD10 and RCC is helpful for differentiating variable cystic renal tumor. MCRCC usually has an excellent prognosis, nephron sparing surgery is first recommended as a therapeutic strategy.

Adenocarcinoma, Clear Cell ; metabolism ; pathology ; Biomarkers ; Carcinoma, Renal Cell ; metabolism ; pathology ; Cysts ; metabolism ; pathology ; Diagnosis, Differential ; Female ; Humans ; Kidney Diseases, Cystic ; metabolism ; pathology ; Kidney Neoplasms ; metabolism ; pathology ; Male ; Neoplasm Recurrence, Local ; Prognosis ; Racemases and Epimerases ; metabolism

Adenoma, Oxyphilic ; metabolism ; pathology ; surgery ; Cadherins ; metabolism ; Carcinoma, Renal Cell ; metabolism ; pathology ; surgery ; Catheter Ablation ; Diagnosis, Differential ; Humans ; Keratins ; metabolism ; Kidney Neoplasms ; metabolism ; pathology ; surgery ; Male ; Middle Aged ; Neoplasms, Multiple Primary ; metabolism ; pathology ; surgery ; Parvalbumins ; metabolism ; S100 Proteins ; metabolism

Objective: To investigate the expression of glycoprotein non metastatic melanoma protein B (GPNMB) in renal eosinophilic tumors and to compare the value of GPNMB with CK20, CK7 and CD117 in the differential diagnosis of renal eosinophilic tumors. Methods: Traditional renal tumor eosinophil subtypes, including 22 cases of renal clear cell carcinoma eosinophil subtype (e-ccRCC), 19 cases of renal papillary cell carcinoma eosinophil subtype (e-papRCC), 17 cases of renal chromophobe cell carcinoma eosinophil subtype (e-chRCC), 12 cases of renal oncocytoma (RO) and emerging renal tumor types with eosinophil characteristics [3 cases of eosinophilic solid cystic renal cell carcinoma (ESC RCC), 3 cases of renal low-grade eosinophil tumor (LOT), 4 cases of fumarate hydratase-deficient renal cell carcinoma (FH-dRCC) and 5 cases of renal epithelioid angiomyolipoma (E-AML)], were collected at the Affiliated Drum Tower Hospital of Nanjing University Medical School from January 2017 to March 2022. The expression of GPNMB, CK20, CK7 and CD117 was detected by immunohistochemistry and statistically analyzed. Results: GPNMB was expressed in all emerging renal tumor types with eosinophil characteristics (ESC RCC, LOT, FH-dRCC) and E-AML, while the expression rates in traditional renal eosinophil subtypes e-papRCC, e-chRCC, e-ccRCC and RO were very low or zero (1/19, 1/17, 0/22 and 0/12, respectively); the expression rate of CK7 in LOT (3/3), e-chRCC (15/17), e-ccRCC (4/22), e-papRCC (2/19), ESC RCC (0/3), RO (4/12), E-AML(1/5), and FH-dRCC (2/4) variedly; the expression of CK20 was different in ESC RCC (3/3), LOT(3/3), e-chRCC(1/17), RO(9/12), e-papRCC(4/19), FH-dRCC(1/4), e-ccRCC(0/22) and E-AML(0/5), and so did that of CD117 in e-ccRCC(2/22), e-papRCC(1/19), e-chRCC(16/17), RO(10/12), ESC RCC(0/3), LOT(1/3), E-AML(2/5) and FH-dRCC(1/4). GPNMB had 100% sensitivity and 97.1% specificity in distinguishing E-AML and emerging renal tumor types (such as ESC RCC, LOT, FH-dRCC) from traditional renal tumor types (such as e-ccRCC, e-papRCC, e-chRCC, RO),respectively. Compared with CK7, CK20 and CD117 antibodies, GPNMB was more effective in the differential diagnosis (P<0.05). Conclusion: As a new renal tumor marker, GPNMB can effectively distinguish E-AML and emerging renal tumor types with eosinophil characteristics such as ESC RCC, LOT, FH-dRCC from traditional renal tumor eosinophil subtypes such as e-ccRCC, e-papRCC, e-chRCC and RO, which is helpful for the differential diagnosis of renal eosinophilic tumors.
Humans ; Kidney Neoplasms/pathology* ; Carcinoma, Renal Cell/pathology* ; Diagnosis, Differential ; Angiomyolipoma/diagnosis* ; Biomarkers, Tumor/metabolism* ; Leukemia, Myeloid, Acute/diagnosis* ; Membrane Glycoproteins

OBJECTIVETo study the expression of a novel marker, kidney-specific-protein (Ksp)-cadherin, in renal epithelial neoplasms and its clinicopathologic significance.

METHODSImmunohistochemical study (using EnVision method) for Ksp-cadherin, CD10, vimentin, epithelial membrane antigen and CK7 was carried out in normal human kidney samples, as well as in 166 cases of primary renal neoplasms (including 120 cases of clear cell renal cell carcinoma (RCC), 20 cases of papillary RCC (type I papillary RCC 15 cases and type II papillary RCC 5 cases), 18 cases of chromophobe RCC and 8 cases of oncocytoma).

RESULTSKsp-cadherin was expressed in distal convoluted tubules of normal kidney in a membranous pattern. It was also detected in 23% (27/120) of clear cell RCC, 20% (4/20) of papillary RCC, 100% (18/18) of chromophobe RCC and 75% (6/8) of oncocytoma. High expression of CD10 and vimentin was noted in clear cell RCC and papillary RCC. CD10 was also expressed in chromophobe RCC in cytoplasmic pattern, compared with membranous staining in the other tumors. CK7 expression was mainly seen in chromophobe RCC and papillary RCC, while epithelial membrane antigen was expressed in all variants of RCC. On the other hand, the expression of Ksp-cadherin in clear cell RCC correlated with tumor stage and grade.

CONCLUSIONSKsp-cadherin is expressed in normal distal convoluted tubules and the related neoplasms. It carries relatively high specificity and sensitivity in diagnosis of chromophobe RCC and oncocytoma. The expression of Ksp-cadherin also correlates with biologic behavior of clear cell RCC.

Adenoma, Oxyphilic ; metabolism ; pathology ; Cadherins ; metabolism ; Carcinoma, Renal Cell ; metabolism ; pathology ; Diagnosis, Differential ; Humans ; Immunohistochemistry ; Kidney Neoplasms ; metabolism ; pathology ; Kidney Tubules ; metabolism ; pathology ; Neoplasm Staging ; Neprilysin ; metabolism ; Vimentin ; metabolism

The inflammatory myofibroblastic tumor (IMT), also knowns as inflammatory pseuduotumor, is a soft tissue lesion of unknown etiology. In the urogenital tract, IMT mainly affects the urinary bladder or prostate, but rarely the kidney. It has been considered as a nonneoplastic reactive inflammatory lesion, but nowadays, it is regarded as a neoplasm due to its high recurrence rate and metastasis. We describe a case of a 61-yr-old woman that had originally been misdiagnosed as renal cell carcinoma, which was pathologically revealed to be an IMT.
Actins/metabolism ; Carcinoma, Renal Cell/diagnosis/pathology ; Diagnosis, Differential ; *Diagnostic Errors ; Female ; Granuloma, Plasma Cell/*diagnosis/pathology/surgery ; Humans ; Kidney Neoplasms/*diagnosis/pathology ; Magnetic Resonance Imaging ; Middle Aged ; Tomography, X-Ray Computed ; Vimentin/metabolism

OBJECTIVETo study the pathologic features and immunophenotype of 3 cases of melanotic epithelioid clear cell tumor of kidney.

METHODSMore than 2000 cases of renal tumors were retrospectively reviewed. Three cases of melanotic epithelioid clear cell tumor were identified. Immunohistochemical study was carried out using the paraffin-embedded tissue samples. Electron microscopy was also performed in 1 case.

RESULTSAmongst the 3 cases studied, the male-to-female ratio is 1:2. Histologically, 2 cases showed a clear cell carcinoma-like pattern. Papillary structures covered by clear cells and eosinophilic cells were observed in 1 case. Immunohistochemical study showed that the tumor cells in all cases expressed HMB 45. Two of them were also positive for Melan A. The staining for epithelial markers and S-100 protein was negative. Melanosomes were not identified by ultrastructural examination.

CONCLUSIONSMelanotic epithelioid clear cell tumor is a rarely seen neoplasm of kidney. There are some histologic overlaps with renal cell carcinoma, epithelioid angiomyolipoma and melanoma. Immunohistochemical study is useful in confirming the diagnosis. The tumor represents a morphologic variant of epithelioid angiomyolipoma.

Adolescent ; Adult ; Angiomyolipoma ; metabolism ; pathology ; surgery ; Carcinoma, Renal Cell ; metabolism ; pathology ; surgery ; Diagnosis, Differential ; Epithelioid Cells ; metabolism ; pathology ; Female ; Follow-Up Studies ; Humans ; Kidney Neoplasms ; metabolism ; pathology ; surgery ; MART-1 Antigen ; metabolism ; Male ; Melanoma-Specific Antigens ; metabolism ; Retrospective Studies