Study: Value of PET for malignant glioma unproven
Further studies are needed to assess the value to patients and physicians of PET and PET/CT imaging in diagnosing the recurrence of highly malignant glioma, with the Institute for Quality and Efficiency in Health Care (IQWiG) finding insufficient evidence to make any summaries or conclusions on the modalities' diagnostic values.
In addition to CT and MRI, PET imaging is conducted on patients with malignant glioma to provide improved accuracy on tumor stage or volume and to diagnose or exclude tumor recurrence, which is common with highly malignant—and typically poor prognostic—glioma.
IQWiG sought to perform a systematic review of studies to determine the accuracy of PET and PET/CT in diagnosing recurrence of highly malignant glioma and to evaluate the benefits to patients of PET as compared with the more standard CT and MRI. The Institute searched EMBASE, MEDLINE and the Cochrane Central Register of Controlled Trials (Clinical Trials), finding just 12 studies conducted over the past 21 years matching its criteria.
Of these 12 identified studies, IQWiG reported that 11 "showed a high risk of bias," while the twelfth study consisted of 12 patients. "[T]he patient groups investigated, the tracers used, the threshold values and reference tests differ so considerably that no summarizing statements or comparisons of the different types of PET diagnostic procedures (devices, tracers, etc.) are possible," the study concluded.
IQWiG said that multi-center studies of high methodological quality "are urgently needed to reliably assess the diagnostic and prognostic accuracy and in particular the patient-relevant benefit or harm of PET and PET/CT in the detection of recurrence of malignant glioma." As it stands, the Institute concluded that the benefit of PET and PET/CT in the detection of recurrence of malignant glioma is unproven.
In addition to CT and MRI, PET imaging is conducted on patients with malignant glioma to provide improved accuracy on tumor stage or volume and to diagnose or exclude tumor recurrence, which is common with highly malignant—and typically poor prognostic—glioma.
IQWiG sought to perform a systematic review of studies to determine the accuracy of PET and PET/CT in diagnosing recurrence of highly malignant glioma and to evaluate the benefits to patients of PET as compared with the more standard CT and MRI. The Institute searched EMBASE, MEDLINE and the Cochrane Central Register of Controlled Trials (Clinical Trials), finding just 12 studies conducted over the past 21 years matching its criteria.
Of these 12 identified studies, IQWiG reported that 11 "showed a high risk of bias," while the twelfth study consisted of 12 patients. "[T]he patient groups investigated, the tracers used, the threshold values and reference tests differ so considerably that no summarizing statements or comparisons of the different types of PET diagnostic procedures (devices, tracers, etc.) are possible," the study concluded.
IQWiG said that multi-center studies of high methodological quality "are urgently needed to reliably assess the diagnostic and prognostic accuracy and in particular the patient-relevant benefit or harm of PET and PET/CT in the detection of recurrence of malignant glioma." As it stands, the Institute concluded that the benefit of PET and PET/CT in the detection of recurrence of malignant glioma is unproven.