world cancer report - iarc

KIDNEY CANCER
SUMMARY
> Cancer of the kidney is the 15 th most
common cancer in the world and most
prevalent in developed countries. Close
to 190,000 cases are diagnosed each
year worldwide and men are generally
affected more frequently than women.
> Tobacco smoking is an established
cause. Excess body weight (obesity) has
also been identified as a risk factor, particularly
in women.
> Patients with late stage diagnosis face a
poor prognosis. Recent advances in
imaging allow the early detection of
asymptomatic tumours. The five-year
survival rate is approximately 50%.
Definition
In adults, 85-90% of cases of kidney cancer
are renal cell carcinomas, a very heterogeneous
group of tumours (mainly
adenocarcinomas) which arise from cells
of the proximal convoluted renal tubule.
Transitional cell carcinoma is a less
common tumour type that arises from
the transitional cell epithelium in the
renal pelvis, ureter and urethra. Wilms
tumour (nephroblastoma) is an embryonal
malignancy that afflicts 1 in 10,000
children.
Epidemiology
The incidence of kidney cancer is considerably
higher in developed countries
than in less developed countries (Fig.
5.142) and appears to be increasing over
the past decade [1,2]. More than
189,000 new cases are diagnosed worldwide
each year. In Western Europe, for
example, kidney cancer is the sixth most
frequently occurring cancer, incidence
being particularly high in the Bas-Rhin
region of France [3]. Incidence is also
exceptionally high in the Czech Republic
< 1.3
< 2.1
Fig. 5.142 Global burden of kidney cancer in men, showing a generally higher incidence in more developed
countries.
and among Scandinavian populations.
Kidney cancer is relatively less common
among Asian and African peoples,
although renal cell carcinoma appears to
be increasing in black American men [4].
Men are affected by kidney cancer more
than women, the sex ratio being 1.6-
2.0:1 [5]. Most cases occur between
ages 50-70, but kidney cancer may be
diagnosed over a broad age range
including young adults [1]. Wilms tumour
is responsible for 5-15% of childhood
cancers, affecting females slightly more
than males. This tumour occurs with
highest frequency in the black population
of USA and Africa, and with lowest
in Eastern Asia [1]. Kidney cancer causes
the deaths of more than 91,000 people
each year.
Etiology
Kidney cancer has consistently been
found to be more common in cigarette
smokers than in non-smokers. The association
was first established as causative for
transitional cell carcinoma of the bladder
< 3.6
< 8.3
Age-standardized incidence/100,000 population
< 22.2
and has now been extended to renal cell
carcinomas, the risk increasing two-fold
for heavy smokers [6]. An increased risk
of renal cell carcinoma has been linked to
obesity, particularly in women, as has
diuretic therapy, again especially in
women [7]. Leather tanners, shoe workers
and dry cleaning employees have an
increased risk as reported in some studies,
as do workers exposed to asbestos
and trichloroethylene. The influence of
beverages, in particular coffee and alcohol,
has not been clearly determined
despite many studies. Phenacetin is carcinogenic:
patients with kidney damage
secondary to phenacetin-containing analgesic
abuse have an increased risk of transitional
cell carcinoma (Medicinal drugs,
p48). Patients with multicystic kidney disease
consequent on long-term dialysis,
adult polycystic kidney disease and tuberous
sclerosis also have an increased
propensity to develop renal cell carcinoma
and von Hippel-Lindau disease, an autosomal
dominant condition, is a predisposing
factor.
Kidney cancer
261