Cost-Effectiveness Analysis of 68Ga-DOTATATE PET/MRI in Radiotherapy Planning in Patients with Intermediate-Risk Meningioma

BACKGROUND AND PURPOSE

While contrast-enhanced MR imaging is the criterion standard in meningioma diagnosis and treatment response assessment, gallium 68Ga-DOTATATE PET/MR imaging has increasingly demonstrated utility in meningioma diagnosis and management. Integrating 68Ga-DOTATATE PET/MR imaging in postsurgical radiation planning reduces the planning target volume and organ-at-risk dose. However, 68Ga-DOTATATE PET/MR imaging is not widely implemented in clinical practice due to higher perceived costs. Our study analyzes the cost-effectiveness of 68Ga-DOTATATE PET/MR imaging for postresection radiation therapy planning in patients with intermediate-risk meningioma.

MATERIALS AND METHODS

We developed a decision-analytical model based on both recommended guidelines on meningioma management and our institutional experience. Markov models were implemented to estimate quality-adjusted life-years (QALY). Cost-effectiveness analyses with willingness-to-pay thresholds of $50,000/QALY and $100,000/QALY were performed from a societal perspective. Sensitivity analyses were conducted to validate the results. Model input values were based on published literature.

RESULTS

The cost-effectiveness results demonstrated that 68Ga-DOTATATE PET/MR imaging yields higher QALY (5.47 versus 5.05) at a higher cost ($404,260 versus $395,535) compared with MR imaging alone. The incremental cost-effectiveness ratio analysis determined that 68Ga-DOTATATE PET/MR imaging is cost-effective at a willingness to pay of $50,000/QALY and $100,000/QALY. Furthermore, sensitivity analyses showed that 68Ga-DOTATATE PET/MR imaging is cost-effective at $50,000/QALY ($100,000/QALY) for specificity and sensitivity values above 76% (58%) and 53% (44%), respectively.

CONCLUSIONS

68Ga-DOTATATE PET/MR imaging as an adjunct imaging technique is cost-effective in postoperative treatment planning in patients with meningiomas. Most important, the model results show that the sensitivity and specificity cost-effective thresholds of 68Ga-DOTATATE PET/MR imaging could be attained in clinical practice.

Phase I/II trial of twice-daily temozolomide and celecoxib for treatment of relapsed malignant glioma: Final data

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Background: Anaplastic astrocytoma (AA) and Glioblastoma multiforme (GBM) overexpress COX-2 enzyme. COX-2 inhibitors demonstrate preclinical efficacy in glioma models and have non-overlapping toxicity with chemotherapy, prompting a phase I/II trial for patients with recurrent/progressive AA or GBM utilizing a regimen of combined temozolomide (TMZ) and celecoxib (CEL). Final survival data is presented. Methods: For phase I, TMZ was given as a fixed loading dose of 200 mg/m2 followed by 9 doses of 90 mg/m2 BID for 5 days. CEL was given in 5 dose levels starting at 60 mg/m2 BID, escalating to 240 mg/m2 BID (maximum 400 mg BID) for 10 days. Cycles were repeated every 28 days until disease progression or toxicity occurred. Results: 46 patients (28 M, 18 F) received 247 cycles of therapy. 37 patients had GBM, 9 AA. Prior treatment was radiation (N=46) and chemotherapy (N=12). No patient received prior TMZ. Median age was 54 years (range 34–74). No dose-limiting toxicity was observed. Hematologic toxicity was mild with Grade 3/4 neutropenia occurring in 3/235 cycles and Grade 3 thrombocytopenia in 3/235 and did not recur following TMZ dose reduction. Grade 1/2 constipation was common, occurring in 28% of patients. No thrombotic events occurred. Overall response rate after 6 cycles was 72%, with 1/18 (5.6%) CR, 7/18 (38.9%) PR, 5/18 (27.8%) SD, and 5/18 (27.8%) PD. Average duration of response was 6 months (range 2–15). Median survival (MS) from time of trial entry for recurrent disease was 8 months (8 months for GBM, 10 months for AA). MS from initial tumor diagnosis was 15 months (15 months GBM, 23 months AA). Conclusion: A regimen of twice-daily TMZ and CEL is safe and potentially effective for the treatment of recurrent/progressive GBM and AA. This combination warrants further study, especially in patients newly diagnosed, given the current use of TMZ in newly diagnosed GBM and the possible value of COX-2 inhibitors in the upfront setting.

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Trigeminal neuralgia: neurosurgical management options

The lancinating facial pain of trigeminal neuralgia usually responds to medical treatment. However, in some patients, trigeminal neuralgia is refractory to drug therapy. In addition, some patients are unable to tolerate the side effects of medication. In these cases, several safe and effective surgical procedures are available for the treatment of this common facial pain syndrome.

MRI changes in intracranial hypotension

We report seven patients with the syndrome of intracranial hypotension who were referred to Memorial Sloan-Kettering, primarily because of suspicion of meningeal tumor or infection raised by the finding of meningeal enhancement on MRI. In three patients, symptoms occurred after lumbar puncture; in four, there was no clear precipitating event. Lumbar puncture after MRI in six patients revealed low CSF pressure (six patients) and pleocytosis or high protein, or both (four patients). Three patients had subdural effusions. Six patients had measurable descent of the brain on midsagittal images. Postural headache resolved in all seven patients, six of whom had follow-up MRIs. Meningeal enhancement resolved or diminished in all six. Subdural effusions resolved spontaneously in two and were evacuated (but were not under pressure) in one. Downward brain displacement improved or resolved in all patients. The clinical syndrome and MRI abnormalities generally resolve on their own. An extensive workup is not helpful and may be misleading. Patients should be treated symptomatically.