International testicular cancer incidence trends: generational transitions in 38 countries 1900-1990.
OBJECTIVE
Rapid increases in testicular cancer incidence have marked the second half of the last century. While these secular rises, observed mainly in countries attaining the highest levels of human development, appear to have attenuated in the last decade, rates continue to increase in countries transiting toward high developmental levels. The purpose of our study was to provide a comprehensive analysis and presentation of the cohort-specific trends in testicular cancer incidence rates in 38 countries worldwide.


METHODS
We used an augmented version of the Cancer Incidence in Five Continents series to analyze testicular cancer incidence in men aged 15-54 in 38 countries, via age-period-cohort analysis.


RESULTS
In many European countries, the USA, Canada, Australia, and New Zealand, there is a continuation of the increasing risk among successive generations, yet rates are attenuating in male cohorts born since the 1970s in several Northern European countries, in contrast to the steeply increasing trends in recent cohorts in Southern Europe. Incidence rates have also been increasing in the populations traditionally at rather low risk, such as in the Philippines, Singapore, China, and Costa Rica.


CONCLUSIONS
The attenuation of testicular cancer risk in younger generations (in the most developed countries) alongside concomitant increases (in countries undergoing developmental change) is indicative of a global transition in the risk of testicular cancer. While identifying the underlying causes remains a major challenge, increasing awareness and adapting national healthcare systems to accommodate a growing burden of testicular cancer may prevent future avoidable deaths in young men.
Section of Cancer Surveillance, International Agency for Research on Cancer, 150, Cours Albert Thomas, 69372, Lyon, Cedex 08, France, znaora@iarc.fr.
Ariana
A
Znaor
Joannie
J
Lortet-Tieulent
Mathieu
M
Laversanne
Ahmedin
A
Jemal
Freddie
F
Bray
D000293:Adolescent; D000328:Adult; D015331:Cohort Studies; D019049:Developed Countries; D003906:Developing Countries; D014943:Global Health; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D013736:Testicular Neoplasms / Q000453:epidemiology* / Q000209:etiology; D055815:Young Adult