What volumetric response defines selumetinib benefit in NF1?

Selumetinib (MEK1/2 inhibitor) achieves ≥20% volume reduction in ~70% of NF1 patients with inoperable plexiform neurofibromas. Partial response (≥20% reduction) is the primary endpoint. Tumor volume ≥3 mL on baseline MRI is typically required for clinical trial enrollment.

What is the MPNST risk in NF1?

Malignant peripheral nerve sheath tumors develop in 8–13% of NF1 patients, representing a lifetime risk ~3000× higher than general population. PET-CT (FDG uptake) and rapid growth (>20%/year), pain, and neurologic change suggest malignant transformation in plexiform neurofibromas.

Neurofibromatosis Tumor Burden Assessment

Quantify plexiform neurofibroma burden in NF1 using volumetric MRI measurements to assess eligibility for selumetinib and monitor treatment response in pediatric and adult patients.

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Neurofibromatosis Tumor Burden Assessment

Frequently Asked Questions

What volumetric response defines selumetinib benefit in NF1?

What is the MPNST risk in NF1?