In Reply: We agree with Dr Cunningham that
while survival benefit is an important outcome, other outcomes that affect
quality of life need to be considered when making screening decisions. However,
the impact of screening on important outcomes such as pain, suffering, or
functional decline has not been studied. Therefore, while it is important
to consider the harms of metastatic cancer, little data are available to estimate
the likelihood that screening will prevent such harms, especially over time
intervals of less than 5 years. Cunningham is technically correct in saying
that if no screening had been done, published rates of cancer mortality might
be slightly higher, causing our estimates of the risk of cancer death to be
slightly lower. However, because rates of screening have historically been
very low in elderly persons, this effect is probably minimal.1
On the other hand, among persons who have had regular screening, our estimates
probably significantly overestimate the benefits of continued screening, as
we discuss in our article.