Get our exclusive Word of the Day images!
nephroblastoma neph·ro·blas·to·ma (něf'rō-blā-stō'mə)
See Wilms tumor.
malignant renal (kidney) tumour of early childhood. In 75 percent of the cases, the tumour grows before the age of five; about two-thirds of the instances are apparent by two years of age. The tumour grows rapidly and can approach the weight of the rest of the body. It rarely appears in adults. In its early stages the nephroblastoma causes no symptoms. Later, symptoms may indicate fever, distortion of the kidney mass, evidence of secondary tumours elsewhere in the body, abdominal and flank pain, weight loss, nausea, loss of appetite, and vomiting.