Wilms' TumourWILMS' TUMOUR About seven percent of all childhood cancers originate in the kidney and nearly all of these are Wilms' Tumours. It is the fifth most common type of childhood cancer and is particularly important because:
Doctors who examine a young patient and find an abdominal mass which feels like a hard, enlarged kidney would order imaging techniques such as X-rays, an intravenous pyelogram, ultrasound or CT scans. At the same time, using similar techniques, they search for metastases (distant spread). The diagnosis of Wilms' Tumour is confirmed during an operation when the tumour (or a specimen of it) is removed and subjected to microscopic examination by a pathologist. There are five recognised stages of Wilms' Tumour: Stage I: this stage of the disease indicates that the tumour is wholly within the kidney and the surrounding capsule; it is completely removed by surgery.Treatment of Wilms' Tumour involves chemotherapy, surgical removal of the tumour and, in the later stages of the disease, radiotherapy. Usually, the tumour is removed by an operation in the first few days, but may be delayed for several weeks if the patient has a very large tumour that must first be shrunk by chemotherapy. In bilateral tumours the surgeon tries to conserve as much as possible of each kidney. Chemotherapy begins soon after diagnosis is established and involves the use of two or three anticancer (or cytotoxic) drugs: Actinomycin D, Vincristine and sometimes Doxorubicin. For Stage I, chemotherapy comprises Actinomycin D and Vincristine for six months. For Stage II, both drugs are given for about 15 months. In Stages III and IV all three cytotoxic drugs are given for 15 months, as well as radiotherapy to all areas of the tumour. Stage V is treated by carefully dissecting the tumour, plus chemotherapy and sometimes radiotherapy. The cure rate varies according to the stage of the disease, being over 90% for Stage I, nearly 90% for Stage II, 70-80% for Stage III, 60% or more for Stage IV and about 50% for Stage V. Sometimes Wilms' Tumour occurs in more than one member of a family. Occasionally, it may be associated with other abnormalities such as enlargement of one side of the body (hemihypertrophy) or absence of the iris in the eye (aniridia). Under the microscope about
10% of tumours show atypical features which may indicate that these patients
need more intensive chemotherapy. Fortunately, most patients with Wilms'
Tumour will be cured.
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