Brain tumor scans reveal which children will respond to experimental cancer drug
Researchers found that baseline MRI measurements can predict which children with recurrent medulloblastoma will benefit from metronomic antiangiogenic therapy. The finding could help oncologists identify candidates for the treatment earlier, potentially improving outcomes and reducing exposure to ineffective therapies.
Originaltitel: Assessment of treatment response in recurrent medulloblastoma using craniospinal MRI.
Kombination av kontrastförstärkt MRI och diffusionsviktad avbildning förbättrar uppföljningen av recidiverande medulloblastom under metronomisk antiangiogen terapi. I MEMMAT-studien analyserade forskare från Medicinska universitet Wien kraniospinal MRI från 40 patienter med tidigare bestrålad recidiverande medulloblastom. Patienter med komplett respons uppvisade månatlig minskning av tumörlesioner på 12,7 procent, medan progressiv sjukdom korrelerade med ökning på 33,7 procent i lesionantal och 56,2 procent i volym. Överensstämmelsen mellan bildmodaliteterna var begränsad — 23 procent av patienterna klassificerades felaktigt med bara en metod. Högre baslinjetumörvolym (≥5,5 ml) förutspådde signifikant kortare överlevnad. Resultaten motiverar rutinmässig multimodal avbildningsprotokoll för terapiövervakning och riskstratifiering vid recidiverande medulloblastom, med direkta konsekvenser för behandlingsplanering i pediatrisk onkologi.
BACKGROUND: To evaluate whether quantitative craniospinal MRI assessment of baseline tumor burden provides prognostic value in patients with recurrent, previously irradiated medulloblastoma undergoing MEMMAT (Metronomic Antiangiogenic) therapy. METHODS: We analyzed craniospinal MRI of 40 patients with recurrent, previously irradiated medulloblastoma enrolled in the MEMMAT trial (April 1, 2014, and March 31, 2021). Ependymal, leptomeningeal, and local relapse lesions were retrospectively manually segmented on T1-contrast-enhanced (T1CE) and diffusion-weighted imaging (DWI) at baseline and follow-up (best response). Lesion count and volume were quantified. Bland-Altman analyses and intraclass correlation coefficients (ICC) assessed inter-sequence agreement., logistic regression evaluated associations between baseline tumor burden and progressive disease. RESULTS: Patients achieving Complete Response (n = 6/40) showed mean monthly decreases of - 12.7% in T1CE lesion count and - 12.9% in volume. Partial Response patients (n = 9/40) showed similar declines (-10.3% and - 13.0%). Stable Disease patients (n = 5/40) demonstrated minimal decreases (-0.8% and - 2.3%). Progressive Disease patients (n = 16/40) showed increases of 33.7% in lesion count and 56.2% in volume. Logistic regression indicated trends toward higher baseline tumor burden predicting PD (volume OR 1.18, p = 0.08; lesion count OR 1.05, p = 0.075). Agreement between T1CE and DWI was limited (ICC 0.35 for lesion count, 0.47 for volume), with 23% of patients misclassified using either modality alone. Survival analyses demonstrated significantly shorter overall survival in patients with baseline lesion volumes ≥ 5.5 ml (log-rank p = 0.003), while a similar association for progression-free survival did not reach statistical significance (p = 0.053). CONCLUSIONS: Combined intracranial and intraspinal T1CE and intracranial DWI assessment improves response evaluation. Exploratory analyses suggested that higher baseline tumor burden may be associated with progression, although the observed associations were of borderline statistical significance and require validation in larger cohorts.