A 45-year-old male was diagnosed with MPNST...Genetic analysis shows NF1 splice-site 1063 mutated, CDKN2A/B/MTAP loss….The first restaging scan after 2 cycles showed stable disease with a 16.7% decrease of target lesions. Restaging after 4 cycles demonstrated an unconfirmed partial response with a 38.9% decrease of target lesions (Fig. 6).