Page 329 - 20dynamics of cancer

Appendix:

Incidence

The first section shows plots of cancer incidence for different tissues
(Figures A.1–A.12). The second section shows plots of the male:female
ratio in incidence for different tissues (Figures A.13–A.18).

Plots of Cancer Incidence at Different Times and Places

The following plots show cancer incidence and acceleration patterns
at different time periods and in different countries. In some cases, the
acceleration plots fluctuate between countries because of the nature of
the data, which may have small numbers of cases at early or late ages.
Thus, it is best to focus only on the broad trends in the acceleration plots,
particularly those patterns that recur in different years and in different
locations. For example, prostate cancer shows a remarkably strong and
linear decline in acceleration beginning in midlife (Figure A.2). Some can-
cers show midlife peaks in acceleration, for example, colon and bladder
cancer (Figure A.4).
Cervical cancer has an acceleration close to zero throughout life, with
higher fluctuations outside the USA probably caused by smaller samples
for those other countries (Figure A.12). However, cervical cancer in the
USA follows different patterns of acceleration in different ethnic groups
(not shown), emphasizing that external factors such as environment and
lifestyle can strongly affect incidence and acceleration. Given the vari-
ability in potential causal factors, the data in the following plots can be
used only to suggest possible hypotheses for further study.