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APPENDIX A
LUNG CANCER 1931—54
in recent years deaths from lung cancer have attracted increasing attention. There
is little doubt that there is a statistical association between smoking and lung cancer and
that extensive cigarette smoking is accompanied by higher lung cancer death rates.
Without entering into the controversy that rages between those who argue that excessive
cigarette smoking causes an increase in the rate of lung cancer, those who argue that
excessive smoking determines merely the site of a cancerous growth without increasing
the over-all risk, and those who deny any association whatever, it was thought desirable
to bring together the available data about lung cancer mortality, incidence and prevalence
relating to the Administrative County of London during the last 25 years.
General
Mortality
Since 1931 the over-all death rate for cancer has risen from 1-48 to 2-04 in England and
Wales and from 1-64 to 2-31 in London. The greater proportion of this apparent rise
in importance of cancer as a cause of death is due to changes in the age structure of the
population ; people no longer die as readily from other causes in early life and the
increasing survival rate coupled with changes in the birth-rate has left relatively more
aged persons to be killed by cancer—a disease of mature age. If the age and sex structure
had remained as it was in 1931 the current death rates would by 1-55 for England and
Wales and 1-73 for London—net increases of-07 and -09 respectively. During the same
period, however, the lung cancer death rate has risen from 0-05 to 0-37 in England and
Wales and 0-12 to 0-54 in London ; on adjustment for age and sex changes during the
period the figures become 0-30 and 0-43 respectively—net increases of 0-25 and 0-31.
The following table illustrates the point :—

It can be seen that while there has been a slight increase in cancer mortality over
the country as a whole and a somewhat greater one in London, these are in fact a reflection
of greater increases in mortality from lung cancer partially offset by decreases in
mortality from cancers of other sites.
The reduction in the rates for other forms of cancer can possibly be attributed to
improved methods of diagnosis and treatment during the period under review but it
will be noted that London has a higher death rate than elsewhere whether one looks
at lung cancer or other cancers. This fact cannot be attributed to marked differences in
population structure between the two areas as the Area Comparability Factor for London
deaths in 1954 was -99. Regional and local differences in cancer death rates have been
investigated by Stocks (1947) who found that during the years 1921-30 London rates
at specified ages from cancer of all sites were above national level, particularly for men,
although they were exceeded by those in Manchester ; that mortality from cancer of the
respiratory organs was higher in urban areas than in rural ; and that there was a significant
negative correlation between hours of bright sunshine and lung cancer. Figures
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