Interval brain imaging for adults with cerebral glioma

Abstract

BackgroundClinical practice guidelines suggest that magnetic resonance imaging (MRI) of the brain should be performed at certain time points or intervals distant from diagnosis (interval or surveillance imaging) of cerebral glioma, to monitor or follow up the disease; it is not known, however, whether these imaging strategies lead to better outcomes among patients than triggered imaging in response to new or worsening symptoms. ObjectivesTo determine the e ect of di erent imaging strategies (in particular, pre-specified interval or surveillance imaging, and symptomatic or triggered imaging) on health and economic outcomes for adults with glioma (grades 2 to 4) in the brain. Search methodsThe Cochrane Gynaecological, Neuro-oncology and Orphan Cancers (CGNOC) Group Information Specialist searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and Embase up to 18 June 2019 and the NHS Economic Evaluation Database (EED) up to December 2014 (database closure). Selection criteriaWe included randomised controlled trials, non-randomised controlled trials, and controlled before-a er studies with concurrent comparison groups comparing the e ect of di erent imaging strategies on survival and other health outcomes in adults with cerebral glioma; and full economic evaluations (cost-e ectiveness analyses, cost-utility analyses and cost-benefit analyses) conducted alongside any study design, and any model-based economic evaluations on pre-and post-treatment imaging in adults with cerebral glioma. Data collection and analysisWe used standard Cochrane review methodology with two authors independently performing study selection and data collection, and resolving disagreements through discussion. We assessed the certainty of the evidence using the GRADE approach. Main resultsWe included one retrospective, single-institution study that compared post-operative imaging within 48 hours (early post-operative imaging) with no early post-operative imaging among 125 people who had surgery for glioblastoma (GBM: World Health Organization (WHO) grade 4 glioma). Most patients in the study underwent maximal surgical resection followed by combined radiotherapy and temozolomide treatment. Although patient characteristics in the study arms were comparable, the study was at high risk of bias overall.Interval brain imaging for adults with cerebral glioma (Review)

A Position Statement on the Utility of Interval Imaging in Standard of Care Brain Tumour Management: Defining the Evidence Gap and Opportunities for Future Research

“…Interval imaging conventions are based predominantly on expert opinion and have been primarily motivated by efforts to standardise outcomes for comparing therapeutic trials ( 9 , 11 ). For EPMRI, it is also noted that indirect contributors to value, such as improving surgical practice ( 5 , 44 ), are challenging to measure, particularly at the start of a complex treatment pathway. Any study design into interval imaging value must consider current or planned therapeutic trials where outcomes are based on interval imaging regimens.…”

“…Whilst the focus of study design relates to the structural MRI interval imaging pathway and by default the “when” of imaging, the “how” and “what else” remain important avenues for research ( 5 ). It is conceivable that the interrogation of biomarkers such as MRI radiomic features, advanced MRI or PET studies can be added as secondary objectives.…”

“…Clinicians, scientists, and patient advocates and representatives with expertise in interval imaging, data science, health economics or trial management of adult brain tumours, convened in London, UK, in April 2019 in conjunction with a National Cancer Research Institute (NCRI) Brain Tumour group workshop. Available evidence for interval imaging pathways for different tumour types was discussed in the context of research recommendations of previous publications, including the UK’s National Institute for Health and Care Excellence (NICE) brain tumour guidelines NG99 ( Supplementary Table 1 ) and a systematic review of glioma imaging ( 4 , 5 , 16 ). Specifically, we sought to assess value in the context of morbidity, mortality, quality of life and resource use (together these outcomes give the additional outcome measure of cost effectiveness).…”

“…Evidence from randomised controlled trials [level 1 ( 3 )] underpins clinical treatments of adult brain tumours. In contrast, there is little evidence (< level 3) to support the current imaging practices used to monitor disease progression or response to treatment ( 4 , 5 ). Therefore, the clinical utility [the relevance and usefulness of an intervention in patient care using all sources of evidence ( 6 )] of interval imaging (imaging at pre-planned time-points to assess tumour status, as compared with scanning for reasons of clinical deterioration) is largely unknown.…”

“…It is also noteworthy that the widely reported observation that increasing enhancement tracks growth of most brain tumour types, has extended the use of contrast-enhancing tumour size as a biomarker beyond high-grade glioma. The impetus to derive an evidence-base is driven by researchers ( 4 , 5 , 16 ), but more importantly patients and carers ( Box 1 ) ( 18 ). This in part relates to factors such as understanding the anxiety surrounding the imaging event and awaiting the results – so-called “scanxiety” ( 19 ).…”