In developing countries cancer is diagnosed late when it is incurable.
More than 80% of cases are diagnosed in advanced stages III and IV
that have a 5-year survival of less than 20%. If through education
there is an increased awareness among physicians, health care workers
and the general public that cancer can be cured if found early and
prompt, effective therapy is available, then more and more cases will
be diagnosed earlier. Eventually more than 80% of cases will be
diagnosed early at stages I and II where there is a good 80% 5-year survival.
This is the pattern seen in a developed country. The phenomenon is
called “downstaging” because new cases are diagnosed at an earlier
stage (staged down from III/IV to I/II). The phenomenon can be measured as
one of the indicators of the effectiveness of screening programs. Early
diagnosis and treatment of cancers has a far greater impact than trying to
treat the disease in its advanced stage.
Along with the education programming for both health care workers
and the public, primary care workers can be trained to detect certain cancers
early and refer them for diagnosis and treatment in countries where formal
population screening programs are unavailable. At a population level this
approach is applicable most to cervical, oral and skin cancers.