Effects of age, birth cohort and period of death on Swiss cancer mortality, 1951-1984.

Swiss death certification data over the period 1951-1984 for total cancer mortality and 30 major cancer sites in the population aged 25 to 74 years were analysed using a log-linear Poisson model with arbitrary constraints on the parameters to isolate the effects of birth cohort, calendar period of death and age. The overall pattern of total cancer mortality in males was stable for period values and showed some moderate decreases in cohort values restricted to the generations born after 1930. Cancer mortality trends were more favourable in females, with steady, though moderate, declines in both cohort and period values. According to the estimates from the model, the worst affected generation for male lung cancer was that born around 1910, and a flattening of trends or some moderate decline was observed for more recent cohorts, although this decline was considerably more limited than in other European countries. There were decreases in cohort and period values for stomach, intestine and oesophageal cancer in both sexes and (cervix) uteri in females. Increases were observed in both cohort and period trends for pancreas and liver in males and for several other neoplasms, including prostate, brain, leukaemias and lymphomas, restricted, however, for the latter sites, to the earlier cohorts and hence partly attributable to improved diagnosis and certification in the elderly. Although age values for lung cancer in females were around 10-times lower than in males, upward trends in female lung cancer cohort values were observed in subsequent cohorts and for period values from the late 1960's onwards. Therefore, future trends in female lung cancer mortality should continue to be monitored. The application of these age/period/cohort models thus provides a summary guide for the reading and interpretation of cancer mortality trends, although it cannot replace careful inspection of single age-specific rates.

[Phot. du plan de la maison de Napoléon à Sainte-Hélène, levé et phot. par Mareschal en 1860-1862, donné en 1888 par Jochem, chef de bataillon du génie en retraite]

Donateur : Jochem (18..-18..)

Childhood cancer in Switzerland: mortality from 1951 to 1984.

Cancer mortality among children in Switzerland was analysed using (1) age-specific and age-standardized (0-14) rates from 1951 to 1984 and (2) comparison of observed numbers of deaths over the period 1960-1984 with expected one obtained by application of age-specific rates for the period 1951-1959 to the population structure of subsequent 5-year calendar periods. Certified mortality fell about 60% for leukaemias, 21% for lymphomas, 66% for Wilms' tumours, 40% for bone sarcomas and 30% for other and unspecified sites. Thus, the overall decline in childhood cancer mortality in Switzerland was around 45%, slightly more marked in females (-48%) than in males (-42%), and more pronounced in younger children (over 50% before age 5). This corresponds to an absolute number of about 50 deaths from childhood cancer per year avoided in the early 1980s as compared with expected numbers computed on the basis of rates registered in the 1950s (30 deaths per year for leukaemias alone). The estimated total number of deaths avoided during the whole period 1960-1980 was 820 (430 leukaemias alone). Trends in childhood cancer mortality persisted steadily downwards in the early 1980s, suggesting that further progress is being achieved in the treatment of these neoplasms.