title: Predictors of locally advanced and metastatic disease in patients with small renal masses.
abstract: Study Type - Prognosis (case series) Level of Evidence 4 What's known on the subject? and What does the study add? There is a small cohort of patients who have small renal masses with metastatic potential, yet risk factors for having this more aggressive disease are largely unknown. In a large sampling of the US population, older patients and men were more likely to have small renal masses at an advanced stage.
  
  
  OBJECTIVE
  To assess the prevalence metastatic and locally advanced renal cell carcinoma (RCC) in the US population with small renal masses (SRMs). To determine what patient and tumour characteristics predict having more advanced SRMs.
  
  
  METHODS
  Using the Surveillance, Epidemiology and End Results (SEER) registry, we identified 14, 962 patients who were diagnosed between 1988 and 2007 with RCC ≤ 3 cm in size. Patients were separated by stage into those with metastatic, locally advanced and localized disease. Differences in baseline characteristics between patients in these three groups were assessed. After controlling for age, sex, grade, tumour size and year of surgery, a logistic regression analysis was performed to determine the likelihood of having non-localized disease.
  
  
  RESULTS
  In the SEER cohort, 13, 574 (90.7%) patients with RCC ≤ 3 cm in size were diagnosed with localized disease, 938 (6.3%) patients had invasion beyond the kidney into regional lymph nodes or nearby organs, and 450 (3.0%) patients had distant metastasis. Patients with metastasis were older (65.9 years) compared to those with localized disease (59.5 years) (P < 0.001). Independent preoperative predictors of having more aggressive disease at diagnosis (locally advanced/metastatic) included older age, particularly age >70 years (odds ratio, OR, 2.42; 95% confidence interval, CI, 2.03-2.88), male sex (OR, 1.50; 95% CI, 1.33-1.70) and tumour size >2.5 (OR, 1.41; 95% CI, 1.25-1.58).
  
  
  CONCLUSIONS
  A small subset (3%) of patients in the USA with RCC ≤ 3 cm in size have distant metastasis. Older patients, men and those with tumours 2.5-3.0 cm in size have a greater probability of presenting with non-localized disease . Clinicians should be aware that there is a risk of metastases in patients with SRMs and also familiarize themselves with the characteristics associated with advanced disease.
authors.affiliation: Department of Urology, Mount Sinai School of Medicine, New York, NY, USA.
authors.forename: Max
authors.initials: M
authors.lastname: Kates
authors.forename: Ruslan
authors.initials: R
authors.lastname: Korets
authors.forename: Neda
authors.initials: N
authors.lastname: Sadeghi
authors.forename: Phillip M
authors.initials: PM
authors.lastname: Pierorazio
authors.forename: James M
authors.initials: JM
authors.lastname: McKiernan
mesh_terms: D000367:Age Factors; D000368:Aged; D002292:Carcinoma, Renal Cell / Q000175:diagnosis / Q000453:epidemiology / Q000556:secondary*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007680:Kidney Neoplasms / Q000453:epidemiology / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D018426:SEER Program; D012737:Sex Factors; D014481:United States / Q000453:epidemiology