Renal neoplasms

Cancers of the kidney account for approximately 1.5 per cent of all cancers and cancer deaths (with an incidence of 5-8 per 100 000 population in the UK, and commoner in males). Three main types of renal cancer are distinguished: (1) Wilms tumour, (2) renal cell carcinoma (RCC) (adenocarcinoma) and (3) medullary and transitional cell cancers of the renal pelvis.

Wilms tumour

Wilms tumour is one of the most common solid tumours in children, with an incidence of approximately 10 per 100 000 live births, and accounting for 8 per cent of all childhood cancers. Both sporadic and familial forms occur, although the latter is uncommon and only 1 per cent of Wilms tumour patients have a positive family history (Breslow et al., 1996). Median age at diagnosis of Wilms tumour is 3-4 years and 80 per cent of patients present by the age of 5 years. Approximately 5 per cent of cases have bilateral tumours, and this subgroup has an earlier age at diagnosis (mean 30 months), and an increased incidence of renal blastemal rests and congenital abnormalities (Breslow and Beckwith, 1982). In contrast to retinoblastoma, the age at onset and proportion of bilateral tumours are not significantly different in familial and sporadic cases. There are important associations between Wilms tumour and sporadic aniridia, Beckwith–Wiedemann syndrome, hemihypertrophy, genitourinary abnormalities, Drash syndrome and Perlman syndrome, Frasier syndrome and Simpson–Golabi syndrome (see part three). In addition, Wilms tumour has been associated occasionally with neurofibromatosis type 1, BRCA1 mutations and Bloom syndrome (Rahman et al., 1996).