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Neuro-oncology Jan 2017Distinction between tumor and treatment related changes is crucial for clinical management of patients with high-grade gliomas. Our purpose was to evaluate whether... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Distinction between tumor and treatment related changes is crucial for clinical management of patients with high-grade gliomas. Our purpose was to evaluate whether dynamic susceptibility contrast-enhanced (DSC) and dynamic contrast enhanced (DCE) perfusion-weighted imaging (PWI) metrics can effectively differentiate between recurrent tumor and posttreatment changes within the enhancing signal abnormality on conventional MRI.
METHODS
A comprehensive literature search was performed for studies evaluating PWI-based differentiation of recurrent tumor and posttreatment changes in patients with high-grade gliomas (World Health Organization grades III and IV). Only studies published in the "temozolomide era" beginning in 2005 were included. Summary estimates of diagnostic accuracy were obtained by using a random-effects model.
RESULTS
Of 1581 abstracts screened, 28 articles were included. The pooled sensitivities and specificities of each study's best performing parameter were 90% and 88% (95% CI: 0.85-0.94; 0.83-0.92) and 89% and 85% (95% CI: 0.78-0.96; 0.77-0.91) for DSC and DCE, respectively. The pooled sensitivities and specificities for detecting tumor recurrence using the 2 most commonly evaluated parameters, mean relative cerebral blood volume (rCBV) (threshold range, 0.9-2.15) and maximum rCBV (threshold range, 1.49-3.1), were 88% and 88% (95% CI: 0.81-0.94; 0.78-0.95) and 93% and 76% (95% CI: 0.86-0.98; 0.66-0.85), respectively.
CONCLUSIONS
PWI-derived thresholds separating viable tumor from treatment changes demonstrate relatively good accuracy in individual studies. However, because of significant variability in optimal reported thresholds and other limitations in the existing body of literature, further investigation and standardization is needed before implementing any particular quantitative PWI strategy across institutions.
Topics: Brain Neoplasms; Combined Modality Therapy; Contrast Media; Glioma; Humans; Magnetic Resonance Angiography; Neoplasm Grading; Prognosis
PubMed: 27502247
DOI: 10.1093/neuonc/now148 -
Journal of Neuro-oncology Jul 2014Which imaging techniques most accurately differentiate true tumor progression from pseudo-progression or treatment related changes in patients with previously diagnosed... (Review)
Review
QUESTION
Which imaging techniques most accurately differentiate true tumor progression from pseudo-progression or treatment related changes in patients with previously diagnosed glioblastoma?
TARGET POPULATION
These recommendations apply to adults with previously diagnosed glioblastoma who are suspected of experiencing progression of the neoplastic process.
RECOMMENDATIONS LEVEL II
Magnetic resonance imaging with and without gadolinium enhancement is recommended as the imaging surveillance method to detect the progression of previously diagnosed glioblastoma.
LEVEL II
Magnetic resonance spectroscopy is recommended as a diagnostic method to differentiate true tumor progression from treatment-related imaging changes or pseudo-progression in patients with suspected progressive glioblastoma.
LEVEL III
The routine use of positron emission tomography to identify progression of glioblastoma is not recommended.
LEVEL III
Single-photon emission computed tomography imaging is recommended as a diagnostic method to differentiate true tumor progression from treatment-related imaging changes or pseudo-progression in patients with suspected progressive glioblastoma.
Topics: Adult; Brain Neoplasms; Diagnosis, Differential; Disease Progression; Evidence-Based Medicine; Gadolinium; Glioblastoma; Humans; Magnetic Resonance Imaging; Magnetic Resonance Spectroscopy; Positron-Emission Tomography; Tomography, Emission-Computed, Single-Photon
PubMed: 24715656
DOI: 10.1007/s11060-013-1330-0 -
Journal of Neuro-oncology Apr 2013Differentiating post radiation necrosis from progression of glioma and pseudoprogression poses a diagnostic conundrum for many clinicians. As radiation therapy and... (Review)
Review
Differentiating post radiation necrosis from progression of glioma and pseudoprogression poses a diagnostic conundrum for many clinicians. As radiation therapy and temozolomide chemotherapy have become the mainstay of treatment for higher-grade gliomas, radiation necrosis and post treatment changes such as pseudoprogression have become a more relevant clinical problem for neurosurgeons and neurooncologists. Due to their radiological similarity to tumor progression, accurate recognition of these findings remains paramount given their vastly different treatment regimens and prognoses. However, no consensus has been reached on the optimal technique to discriminate between these two lesions. In order to clarify the types of imaging modalities for recurrent enhancing lesions, we conducted a systematic review of case reports, case series, and prospective studies to increase our current understanding of the imaging options for these common lesions and their efficacy. In particular, we were interested in distinguishing radiation necrosis from true tumor progression. A PubMed search was performed to include all relevant studies where the imaging was used to differentiate between radiation necrosis and recurrent gliomas with post-radiation enhancing lesions. After screening for certain parameters in our study, seventeen articles with 435 patients were included in our analysis including 10 retrospective and 7 prospective studies. The average time from the end of radiation therapy to the onset of a recurrent enhancing lesion was 13.2 months. The most sensitive and specific imaging modality was SPECT with a sensitivity of 87.6 % and specificity of 97.8 %. Based on our review, we conclude that certain imaging modalities may be preferred over other less sensitive/specific techniques. Overall, tests such as SPECT may be preferable in differentiating TP (tumor progression) from RN (radiation necrosis) due to its high specificity, while nonspecific imaging such as conventional MRI is not ideal.
Topics: Brain Neoplasms; Diagnosis, Differential; Diagnostic Imaging; Disease Progression; Glioma; Humans; Necrosis; Radiation Injuries
PubMed: 23344789
DOI: 10.1007/s11060-013-1059-9