Screening for prostate cancer: systematic review and meta-analysis of randomised controlled trials

Metaanalysis should summarize information by pooling data from
studies with congruent design. If this precondition is not fulfilled, the
conclusions drawn from a metaanalysis are rather doubtful and could be
misleading.1 The metaanalysis by Djulbegovic and colleagues including six
studies of heterogenous design is apparently such an example.1 Several
conclusions have been drawn from the contradictory results of the two
large ERSPC and PLOC screening trials published in 2009.2;3 Furthermore,
it is questionable if a study initially not including PSA and only
accounting for 0.39% of all patients4 should be included even if a long
follow up is available. A more serious problem is the inclusion of the
Quebec study,5 which has been criticize for several drawbacks.6 The design
of the Quebec study, the method of analysis, and the fact that only 23% of
those approached participated were main problems of this trial.6 On the
other hand, a large regional screening trial from Tyrol was not included
in this metaanalysis.7 When excluding the extreme small study4 and the
Quebec study5 there would be only 4 studies, where 3 studies are the ERSPC
or parts of the ERSPC study.

We appreciate the detailed analysis of the authors but we cannot
follow their conclusions. From our viewpoint it is more likely that the
well conducted ERSPC study with 20% mortality reduction8 and newer sub-
studies with 44% mortality reduction9 indicate the real value of PSA
screening than a summary based on old and partially insufficient data. It
is highly assumable that further updates of those ERSPC studies with
sufficient design will favor even more PSA screening.

Funding None

Competing interests:
Carsten Stephan has no conflicts of interest.
Kurt Miller has no conflicts of interest.
Klaus Jung has no conflicts of interest.

Copyright
The Corresponding Author has the right to grant on behalf of all authors
and does grant on behalf of all authors.

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