CHAPTER X CHAPTER 4 - Cancer et environnement

Germ cell tumours
P.J. Woodward
A. Heidenreich
L.H.J. Looijenga
J.W. Oosterhuis
D.G. McLeod
H. Møller
J.C. Manivel
F.K. Mostofi
S. Hailemariam
M.C. Parkinson
K. Grigor
L. True
G.K. Jacobsen
T.D. Oliver
A. Talerman
G.W. Kaplan
T.M. Ulbright
I.A. Sesterhenn
H.G. Rushton
H. Michael
V.E. Reuter
Epidemiology
The incidence of testicular germ cell
tumours shows a remarkable geographical
variation. The highest level of incidence,
around 8-10 per 100,000 world
standard population (WSP) are found in
Denmark, Germany, Norway, Hungary
and Switzerland {749}. The only population
of non European origin with a similar
high level of incidence is the Maori population
of New Zealand with 7 per
100,000 WSP {2016}. In populations in
Africa, the Caribbean and Asia the level
of incidence is typically less than 2 per
100,000 WSP.
In general, the incidence of testicular
germ cell tumours has been increasing in
most populations of European origin in
recent decades {481}.
The age distribution of testicular germ
cell tumour is unusual. The incidence
increases shortly after the onset of
puberty and reaches a maximum in men
in the late twenties and thirties.
Thereafter, the age specific incidence
rate decreases to a very low level in men
in their sixties or older. Consistent with
the geographical variation in incidence,
the area under the age incidence curve
is very different in populations with different
levels of incidence, but the general
shape of the curve is the same in low risk
and in high risk populations {1766}. The
age incidence curves of seminoma and
Fig. 4.02 Germ cell tumours. European annual incidence per 100,000 of testicular cancer. From Globocan 2000 {749}.
Fig. 4.01 Germ cell tumours. Age specific incidence rates of testicular cancer in South East England, 1995-
1999. Source: Thames Cancer Registry.
non-seminoma are similar, but the modal
age of non-seminoma is about ten years
earlier than seminoma. This probably
reflects the more rapid growth and the
capacity of haematogenic spread and
metastasis of non-seminomas.
In Denmark, Norway and Sweden the
generally increasing incidence over time
was interrupted by unusual low incidence
in men who were born during the
Second World War {222,1766}. The reasons
for this phenomenon are not known
but it illustrates several important characteristics.
Firstly, that the risk of developing
testicular cancer in men in high
risk populations is not a constant, but
appears to be highly and rapidly susceptible
to increasing as well as
decreasing levels of exposure to casual
factors. Secondly, the risk of developing
testicular tumour is susceptible to
changes in everyday living conditions
and habits, as these occurred with
respect to changes in the supply and
consumption situation in the Nordic
countries during the Second World War.
Finally, the relatively low level of incidence
throughout life of men in the
Germ cell tumours 221