Syndromic Wilms tumor: a review of predisposing conditions, surveillance and treatment.

Predisposing syndromes associated with an increased risk of Wilms tumor (WT) are responsible for 9-17% of all cases of the malignancy. Due to an earlier age at WT diagnosis and an increased incidence of bilateral and metachronous disease, management of syndromic WT warrants a distinct approach from that of non-syndromic WT. This review of English-language manuscripts about WT focuses on the most common syndromes, surveillance protocols and current treatment strategies. Highlighted syndromes include those associated with , such as WAGR (Wilms-Aniridia-Genitourinary-mental Retardation), Denys-Drash syndrome (DDS), and Frasier syndrome, defects, such as Beckwith-Wiedemann syndrome (BWS), among others. General surveillance guidelines include screening renal or abdominal ultrasound every 3-4 months until the age of 5 or 7, depending on the syndrome. Further, some of the predisposing conditions also increase the risk of other malignancies, such as gonadoblastoma and hepatoblastoma. With promising results for nephron-sparing surgery in bilateral non-syndromic WT, there are increasing reports and recommendations to pursue nephron-sparing for these patients who are at greater risk of bilateral, metachronous lesions. In addition to the loss of renal parenchyma from malignancy, many patients are at risk of developing renal insufficiency as part of their syndrome. Although there may be some increase in the complication rate, recurrence free survival seems equivalent. Some conditions require specialized approaches to adjuvant therapy, as their syndrome may make them especially susceptible to side effects.