renal mass

Etiology

• renal cysts (65-70%)
• infected cyst, abscess
• polycystic kidney disease
• renal carcinoma
• angiomyolipoma (<= 1 cm)

Epidemiology

• 50% of population > 5 years of age has >= 1 renal mass

Clinical manifestations

• generally asymptomatic, incidental finding

Laboratory

• urinalysis
• serum creatinine, serum urea nitrogen
• complete blood count, (infection, anemia)

Radiology

• ultrasound (0%, 21%, 28%)*
  • determines if mass is cystic or solid
• contrast-enhanced computed tomography (47%, 60%, 75%)*
  • involvement of surrounding tissue
  • invasion of the renal vein
  • regional lymphadenopathy
• magnetic resonance imaging

* Percentages of renal lesions detected, 0-5 mm, 5-10 mm, 10-15 mm in size, respectively

* < 2% of hyperechoic lesions <= 1 cm in size may represent renal carcinoma

Management

• see specific etiology
• preoperative needle biopsy
  • generally not recommended for resectable lesion
    • concern for 'seeding' the pertoneum
  • useful if imaging studies inconclusive

More general terms

• mass lesion
• kidney disease; renal disease