Case 2: Charly (17 years old)

Charly is a 17-year-old student with neurofibromatosis type 1 (NF1). In childhood, he was closely monitored for a local diffuse plexiform neurofibroma (PN) of the left sacroiliac joint and back. He was lost to follow-up during puberty, experiencing school difficulties and frustration with frequent medical visits.

He presents again today:

• Medical history:
  • Resection of small superficial lump at age 8
  • Focal seizures controlled on daily oxcarbazepine
• Symptoms: severe left-sided low back and sacral pain causing significant functional limitation
• Blood work: no abnormalities
• MRI: diffuse PN of the lower back with infiltration of the sacroiliac joint

Mirdametinib treatment was started. Assessment summary 6 months later:

• Stable disease
• Severe skin toxicity with acneiform rash and paronychia (CTCAE grade 3)
• Daily oxcarbazepine discontinued

Local/systemic skin therapy is being started to manage the skin toxicity.