title: Tumor necrosis on magnetic resonance imaging correlates with aggressive histology and disease progression in clear cell renal cell carcinoma.
abstract: OBJECTIVE
  The study objective was to correlate the magnetic resonance imaging (MRI) features of clear cell renal cell carcinoma (ccRCC) with the histopathologic features and disease progression.
  
  
  METHODS
  Institutional review board approval for this retrospective study was obtained; patient consent was not required. The initial staging MRI scans of 75 patients with histologically confirmed ccRCC were retrospectively reviewed. The imaging was assessed by 2 radiologists for the presence of tumor necrosis, cystic degeneration, intracellular fat, hemorrhage, retroperitoneal collaterals, and renal vein thrombosis. Quantitative analysis for the MRI presence of intracellular lipid within tumors was performed. MRI findings were correlated with histopathologic findings of clear cell percentage, alveolar and tubular growth pattern, and disease progression. Statistical associations were evaluated with nonparametric univariable analyses and multivariable logistic regression models.
  
  
  RESULTS
  Correlation between MRI and histopathologic features was performed in 75 patients, whereas follow-up data were available for progression analysis in 68 patients. The presence of tumor necrosis, retroperitoneal collaterals, and renal vein thrombosis on MRI was significantly associated with a low percentage of tumor cells with clear cytoplasm (P < .01) and metastatic disease at presentation or disease progression (P < .01). At multivariable analysis, necrosis remained the only feature statistically associated with disease progression (P = .03; adjusted odds ratio, 27.7; 95% confidence interval, 1.4-554.7 for reader 1 and P = .02; adjusted odds ratio, 29.3; 95% confidence interval, 1.7-520.8 for reader 2).
  
  
  CONCLUSIONS
  Necrosis in ccRCC on MRI correlates with the histopathologic finding of lower percentage of tumor cells with clear cytoplasm and is a poor prognostic indicator irrespective of tumor size.
authors.affiliation: Department of Radiology, St. James Hospital and Trinity College, Dublin, Ireland.
authors.forename: Peter
authors.initials: P
authors.lastname: Beddy
authors.affiliation: Department of Pathology, Beth Israel Deaconess Medical Center, Boston, MA.
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Genega
authors.affiliation: Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA.
authors.forename: Long
authors.initials: L
authors.lastname: Ngo
authors.affiliation: Department of Radiology, New York University Langone Medical Center, New York, NY.
authors.forename: Nicole
authors.initials: N
authors.lastname: Hindman
authors.affiliation: Department of Radiology, St. James Hospital and Trinity College, Dublin, Ireland.
authors.forename: Jesse
authors.initials: J
authors.lastname: Wei
authors.affiliation: Department of Medicine, Division of Hematology/Oncology, Beth Israel Deaconess Medical Center, Boston, MA.
authors.forename: Andrea
authors.initials: A
authors.lastname: Bullock
authors.affiliation: Department of Medicine, Division of Hematology/Oncology, Beth Israel Deaconess Medical Center, Boston, MA.
authors.forename: Rupal S
authors.initials: RS
authors.lastname: Bhatt
authors.affiliation: Department of Medicine, Division of Hematology/Oncology, Beth Israel Deaconess Medical Center, Boston, MA.
authors.forename: Michael B
authors.initials: MB
authors.lastname: Atkins
authors.affiliation: Department of Radiology, St. James Hospital and Trinity College, Dublin, Ireland. Electronic address: ivan.pedrosa@UTsouthwestern.edu.
authors.forename: Ivan
authors.initials: I
authors.lastname: Pedrosa
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002292:Carcinoma, Renal Cell / Q000000981:diagnostic imaging* / Q000473:pathology; D018450:Disease Progression; D005260:Female; D006801:Humans; D007673:Kidney Cortex Necrosis / Q000000981:diagnostic imaging*; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012082:Renal Veins / Q000000981:diagnostic imaging; D012189:Retrospective Studies; D013927:Thrombosis / Q000000981:diagnostic imaging
keywords: MRI; carcinoma; clear cell metastatic renal cell carcinoma; clear cell percentage; kidney neoplasms