unifrib oktttrs ocnMir - Legacy Tobacco Documents Library

.
ty 7
examinati.ons have long boen the rule, the increased
i .ncr".dence of lung cancer was reported. about the turn of
the ccmtury, long before cigaretto snaking became popular .
The hi.g9nestt incidence of lung cancer is at approxi-
rnato] .y 57 ycars of ago i.n smokers an d non-smokers aliko .
Thio poak incidence irs maintained very strictly regard-
loss of omoking habits . If cigarette smoking wore a factor,
one would expect hoervy and prolonged smokers to develop
cauccr at an oarlier age than others . One would also
expect that :Lun e: cancer incidence in smokers would eon-
t9.uue to iue?roase with advancing age, yet lung cancer
shows a sharp decYSUe after 65, rogardloss of cigarette
consumpti.on .
http://legacy.library.ucsf.edu/tid/hly24f00/pdf
In rospoct to the tissue changes reportedly observod
in post -mortom exoan9.nationn of the lungs of heavy smokers,
it should be pointed out that sirni .lar changos are not
uncommon in the 7.rmgs of non-smokers, have boon produced
oxpr.r.imontally in animals by a variety of agents completely
unrelated to tobacco smoke, and have been demonstrated
to bo reversible so that the bronchial tubes may return
to normal and no cancer develops . If these changes wore
always premaaiEonant, they should not be reversible .
During my years an a practicing doctor I have soon
many changes in the general population of this country .
btedi .cal advenccs have certainly not boon limited to
1 .7b6