The
benefit of positron emission tomography (PET) in oesophageal cancer must be
considered as not proven due to a lack of comparative studies. In terms of
diagnostic and prognostic accuracy, it also remains unclear whether the
diagnostic technique can detect the spreading of tumors better than other
modalities. This is the conclusion of the final report of the German Institute
for Quality and Efficiency in Health Care (IQWiG) published on 20 August 2013.
About 4800 men and 1400 women are newly diagnosed with esophageal cancer in
Germany each year. The average age of disease onset is 65 years. and the 5-year
survival rate in Germany is at most 20%. Many experts assume that an
examination using PET or PET/CT, alone or in combination with other methods, is
better able to stage the tumor and monitor response to treatment. In addition,
better detection of tumor recurrence ought to be possible.
IQWiG
therefore searched the international literature for studies that had examined
the consequences of diagnostic interventions using PET or PET/CT with regard to
whether they were accompanied by perceptible improvements for patients, such as
increase in survival rates or quality of life, or fewer operations or further
diagnostic interventions. However, the search for direct comparative
intervention studies was unsuccessful, so that the question regarding the
patient-relevant benefit of PET or PET/CT in esophageal cancer still remains to
be answered. IQWiG also searched for studies in which the diagnostic accuracy
and prognostic power of PET or PET/CT was compared with other examination
methods. For this a total of 48 studies were found to be relevant for
diagnostic and prognostic accuracy, of which most examined the accuracy of
primary staging. Nineteen studies directly compared PET with CT. However,
conclusions in favour of one or the two techniques cannot be drawn, as either
no statistically significant difference was shown or the data could not be
interpreted with sufficient certainty. Too few studies are so far available that
directly compared PET or PET/CT with other diagnostic techniques and
investigated treatment response (restaging) or diagnosis and prognosis of tumor
recurrence. A reliable conclusion on the diagnostic and prognostic accuracy of
PET or PET/CT in restaging or recurrence diagnostics is therefore not possible.
In particular the potential advantage of PET and PET/CT, which visualize
metabolic activity, remains unclear versus morphologic imaging techniques such
as CT or magnetic resonance imaging, which display anatomical structures.