Benefit of PET in Esophageal Cancer Not Proven

A new report claims that the patient benefits of positron emission tomography (PET) in esophageal cancer, either alone or in combination with computed tomography (CT), are not proven.

Researchers at the German Institute for Quality and Efficiency in Health Care (IQWiG; Köln, Germany) searched 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 an increased of chances of survival or improved quality of life), or spared them unnecessary operations or further diagnostic interventions. 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 remains open.

The researchers also searched for studies in which the diagnostic accuracy and prognostic power of PET or PET/CT was compared with other examination methods. They found 48 studies relevant for diagnostic and prognostic accuracy, of which most examined the accuracy of primary staging. However, 19 studies directly compared PET with CT; the conclusions in favor of one or the two techniques could not be drawn, as either statistically significant difference was not shown or the data could not be interpreted with sufficient certainty. The report was published by IQWiG on August 20, 2013.

“A reliable conclusion on the diagnostic and prognostic accuracy of PET or PET/CT in restaging or recurrence diagnostics is therefore not possible,” concluded the researchers. “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.”

About 4,800 men and 1,400 women are newly diagnosed with esophageal cancer in Germany alone each year. The average age of disease onset is 65 years, and the 5-year survival rate is at best 20%. Many experts assume that an examination using PET or PET/CT is better able to evaluate how far a tumor has spread (staging) and whether it has responded to treatment (restaging); in addition, better detection of tumor recurrence ought to be possible.

Related Links:
German Institute for Quality and Efficiency in Health Care