Follow-up of Glioblastoma after Surgical Resection
Protocol for Post-Operative Imaging
- A cranial MRI should be performed within 24-48 hours after surgical intervention to accurately distinguish residual tumor tissue from post-operative edema and surgical changes 2, 3, 4
- The European Society for Medical Oncology recommends that lumbar puncture is generally not necessary in the follow-up of glioblastoma and staging of other organs is not required 2, 3
Clinical Evaluation During Follow-up
- The American College of Neurology recommends a complete neurological examination to assess neurological function 5, 1
- Monitoring of seizures or equivalent epileptic events should be performed 5
- The use of corticosteroids should be evaluated with the goal of gradually reducing the dosage as soon as possible 1
- Surveillance for venous thrombotic events, which occur frequently in patients with residual or recurrent tumor, should be performed 1
Frequency and Modality of Imaging
- The European Society for Medical Oncology recommends that cranial MRI every 3-4 months represents the standard practice outside of clinical trials 1
- Contrast-enhanced MRI is the preferred imaging modality for evaluating response 5
Critical Issue: Pseudoprogression
- The enhancement and presumed tumor progression on imaging 4-8 weeks after the end of radiotherapy can represent an imaging artifact due to changes in the blood-brain barrier permeability (pseudoprogression) 5
- This pseudoprogression should be confirmed with a second MRI 4 weeks later before modifying the therapeutic plan 5
Criteria for Evaluating Response
- The response to chemotherapy should be evaluated according to the Macdonald criteria, which include not only tumor size according to WHO criteria but also the evaluation of neurological function and the use of corticosteroids 5
Management of Corticosteroids
- The American College of Neurology recommends gradually reducing the use of steroids as soon as possible to minimize long-term side effects such as myopathy, hyperglycemia, opportunistic infections, and psychiatric complications 1