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Key Points
Wilms’ tumor is a common cause of renal neoplasms in children but is rarely diagnosed in utero.
The main differential diagnosis in Wilms’ tumor is mesoblastic nephrosis.
Wilms’ tumor may present in utero as part of Perlman syndrome (ascites, polyhydramnios, hepatomegaly, macrosomia, and Wilms’ tumor).
Wilms’ tumor may present as part of recognized genetic conditions including Beckwith–Wiedemann syndrome, Denys-Drash syndrome, WAGR syndrome, Fanconi anemia, and Simpson–Golabi–Behmel syndrome.
Excellent survival is achieved with current therapies including surgery, chemotherapy, and in some cases radiation therapy.
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Renal neoplasms account for approximately 10% of all malignant tumors in children (Breslow and Beckwith, 1982). Nephroblastoma (Wilms’ tumor) accounts for 80% of renal neoplasms in children, while other tumor types, such as anaplastic sarcoma, clear cell sarcoma, rhabdoid tumor, and renal cell carcinoma account for the rest. Wilms’ tumor has a peak incidence at 2 to 3 years of age, but it can present from fetal life to adulthood (Breslow et al., 1988a,b). However, neonatal Wilms’ tumor is unusual, with only 5 cases reported to the National Wilms’ Tumor Study among 3340 reported between 1969 and 1984 (Hrabovsky et al., 1986; Ritchey et al., 1995). Several cases now have been diagnosed in utero (Giulian, 1984; Ritchey et al., 1995; Applegate et al., 1999; Vadeyar et al., 2000; Cavicchioni et al., 2005).
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Nephroblastoma is a tumor that arises within the kidney and consists of a variety of embryonic tissues such as glomeruli and tubules, spindle cells, smooth and skeletal muscle fibers, cartilage, and bone. Wilms’ tumor is associated with many genetic conditions, including Beckwith–Wiedemann, Denys–Drash, Klippel–Trenaunay syndromes and neurofibromatosis and the WAGR complex (Wilms’ tumor, aniridia, genito urinary malformations, and mental retardation) (King, 1993), suggesting a genetic predisposition to Wilms’ tumor (Jadresic et al., 1990). However, the most common presentation of Wilms’ tumor is an asymptomatic abdominal mass. Abdominal pain, hematuria or malaise, weakness, anorexia, and weight loss may also be presenting symptoms.
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Fetal Wilms’ tumor may present as part of Perlman syndrome, which is characterized by familial nephroblastomatosis, fetal ascites, polyhydramnios, hepatomegaly, macrosomia, and Wilms’ tumor (Greenberg et al., 1986; Perlman, 1986). Wilms’ tumor in Perlman syndrome occurs in the absence of chromosomal abnormalities, enzymatic defects, or somatic conditions known to be associated with Wilms’ tumor. Nephroblastomatosis may present as either diffuse or discrete rests of abnormally persistent embryonic renal blastema. In some instances, this condition is believed to be a premalignant precursor of Wilms’ tumor (Kulkarni et al., 1980; Stone et al., 1990). Nephroblastomatosis has been defined by Ambrosino et al. (1990) as either persistent metanephric blastema in infants over 36 weeks of gestation or the presence of persistent metanephric blastema in an abnormal location and/or quantity in younger fetuses. Nephrogenic rests occur as two ...