Renal tumours of childhood represent a fascinating group of tumours in which
very significant discoveries have been made in the last 100 years, leading to
better understanding of these not only tumours but also tumour in general. By
studying a large series of renal tumours of childhood collected through
international multicentre trials, their clinico-pathological features have
been better recognised resulting in more appropriate treatment and better
prognosis, numerous new tumour entities have been identified, and thank to
new molecular biology studies and techniques, many tumour genes and genetic
abnormalities which are important in tumorigenesis have been found. The most
common renal tumour of childhood is Wilms? tumour, which is now regarded as
the most treatable tumour in children with overall survival of 90%. New
multicentre trials are focused on reduction of treatment in order to avoid
longterm sequalae of treatment, but without jeopardising these excellent
survival results. Histopathological studies are searching for subtypes of
Wilms? tumour, which could be treated with milder therapy, and in a recently
launched trial patients will be stratified in different treatment groups on
the basis of molecular features of their tumours. Molecular biology studies
have helped us recognising that some renal tumours are identical to tumours
of other sites (such as cellular mesoblastic nephroma and infantile
fibrosarcoma of soft tissue, renal and extra-renal rhabdoid tumour), as well
as that some tumours of other sites may also occur in the kidney (primitive
neuroectodermal tumour, desmoplastic small round cell tumour, synovial
sarcoma). Finally, some new, kidney-specific entities have been recognised
too (metanephric stromal tumour, metanephric adenofibroma, anaplastic sarcoma
of the kidney). It is very likely that new advances in molecular biology will
result in identification of features, which are going to be even more
important in predicting tumour behaviour, response to treatment and
prognosis.
Claudins and Ki-67
