- A malignant tumor of the kidney in young children. Nephroblastoma is also known (better known today) as Wilms tumor. Whatever name one cares to use, it is the most common kidney cancer in children and one the most important malignancies in childhood. About 450 new cases of are diagnosed each year in the U.S. The tumor has a characteristic appearance under the microscope. (It is composed of small spindle cells and other types of tissue, including kidney tubules and glomeruli, and muscle and cartilage.) The treatment of Wilms tumor exemplifies the effectiveness of combining surgery, chemotherapy, and radiation in the treatment of children with cancer. The mortality (death) rate from Wilms tumor was over 60% in the 1950s. However, the survival rate (without recurrence) 2 years after diagnosis now exceeds 90%. Risk factors for the recurrence of Wilms tumor — when it recurs, it tends to stay in the locality not far where it started — include an advanced stage of the tumor (particularly if there is involvement of the lymph nodes near the aorta), an unfavorable microscopic appearance of the tumor, and spillage of tumor cells at the time of surgery. The name Wilms is neither plural nor possessive. It is the family name of Max Wilms, a German surgeon (1867-1918) who described the tumor.
* * *SYN: Wilms tumor.
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* * *n.a malignant tumour arising from the embryonic kidney and occurring in young children, usually below the age of three and rarely over the age of eight. In some cases it involves both kidneys. Treatment consists of removing the kidney (see nephrectomy) and giving chemotherapy. Although almost half the cases have spread by the time diagnosis is made, this does not prevent a cure: the number of children that survive at least five years after diagnosis is improving, being currently around 75%. In some children the tumour is associated with an abnormality of chromosome number 13; in these cases other features, such as absence of the iris in the eye (see aniridia) and hemihypertrophy, are present.
* * *neph·ro·blas·to·ma (nef″ro-blas-toґmə) Wilms tumor.
Medical dictionary. 2011.