Purpose: Approximately 20 to 35% of meningiomas are classified as World Health Organization
(WHO) grade II or III, conferring increased risk of recurrence and lower overall survival.
Accurate imaging is particularly important in this patient population, as postoperative
scarring can confound the interpretation of conventional contrast-enhanced MRI. Somatostatin
receptor 2 (SSTR2) is overexpressed in meningiomas, with very low expression in normal
brain, meninges, and cranial soft tissues, allowing tumor visualization with positron
emission tomography (PET) using somatostatin analogues such as Ga68-DOTATATE. DOTATATE
PET has previously demonstrated superiority in the detection of postoperative recurrence
as well as delineation of osseous and parenchymal invasion compared with MRI. While
PET/MRI confers a higher cost of imaging compared with MRI alone, it has the potential
of saving healthcare costs through decreasing radiation volumes (and thereby number
of visits), as well as decreasing associated morbidity. Our purpose was to perform
cost-effectiveness analysis of PET/MR in patients with intermediate-risk meningioma
undergoing radiotherapy planning.
Materials and Methods: We performed a cost-effectiveness analysis of DOTATATE-PET/MRI or PET/CT for planning
of radiotherapy in recurrent benign and malignant (intermediate-risk) meningiomas
using a decision model to compare the effectiveness in terms of quality-adjusted life
years (QALYs) and costs. PET/MRI or PET/CT was considered the “new strategy” and MRI
was considered the “standard strategy.” Radiotherapy guidelines for intermediate-risk
meningiomas were based on the NRG Oncology phase-II trial (RTOG 0539). The clinical
outcomes were categorized in two groups: none-to-minor disability, and moderate-to-severe
disability. The probabilities for progression and clinical outcomes with each strategy
were determined based on published studies. The probabilities assigned for the development
of progression and clinical outcomes in patients who underwent DOTATATE PET for RT
planning were derived from a prospective cohort at our institution. Additionally,
probabilities for the standard strategy were derived from a retrospective institutional
cohort. The endpoint costs included in the decision model were those of radiotherapy,
disability, and those of the standard and new imaging strategy. One-way sensitivity
analyses were performed. A willingness-to-pay (WTP) threshold of $100,000 was assumed.
Results: The per-person cost for the PET/MRI (new) strategy was $349,067. The per-person cost
for the MRI (standard) strategy was $889,079. The new strategy resulted in a gain
of 21.28 QALYs. The standard strategy resulted in a gain of 18.11 QALYs. Because the
PET/MRI strategy resulted in lower costs and higher QALYs gained, it was dominant
over the standard strategy. Our results remained robust when varying multiple variables
across a range of 0 to 1.
Conclusion: DOTATATE PET/MRI has recently been demonstrated to convey added benefits in the evaluation
and treatment planning of meningiomas, particularly those in the intermediate-risk
group. Our pilot cost-effectiveness analysis model demonstrated DOTATATE PET/MRI to
be dominant over MRI alone, with higher QALYs and lower costs. Limitations of the
study, to be addressed in future work, include the small cohort size and lack of long-term
follow-up data of our institutional cohort. Our pilot data supports the use of DOTATATE
PET/MRI in the management of intermediate-risk meningiomas.
Decision Model
Input Parameters
