First immunotherapy trial for the soft-tissue sarcoma MPNST, an orphan disease
A collaborative clinical study (PI: Tormod K. Guren) at OUS reports a long-lasting response to immune check point inhibition in 1 of 8 patients with malignant peripheral nerve sheath tumors (MPNSTs). Multiplex fluorescent immunohistochemistry showed high tumor density of PD-1+CD8+ T cells in tumors with treatment response. In addition, mixed response in a 2nd patient was associated with high PD-L1 expression.
MPNSTs are rare, aggressive, and associated with the hereditary syndrome neurofibromatosis type 1. Surgery is the only curative treatment, but the recurrence rate is high. MPNST is considered an orphan disease with few effective treatment options or clinical trials. This study was possible due to a dedicated multidisciplinary collaboration across divisions at OUS, and was recently published in npjPrecision Oncology by Sveen A, Bergsland CH, Niederdorfer B, Berstad AE, Bjerkehagen B, Boye K, Guren TK and Lothe RA.
Prospective Norwegian patients with advanced MPNST will be offered testing for immune marker expressions using fluorescent multiplex immunohistochemistry in a collaboration between the Lothe lab and InPred- national infrastructure for precision cancer diagnostics (Leader: Hege Russnes). Positive cases may be eligible for immune therapy in the trial Matrix Rare (PI: Åslaug Helland)
Links:
The article:
Sveen A, Bergsland CH, Niederdorfer B, Berstad AE, Bjerkehagen B, Boye K, Guren TK, Lothe RA (2026)
Pembrolizumab in advanced malignant peripheral nerve sheath tumors: a single-arm phase 2 trial
NPJ Precis Oncol, 10 (1)
DOI 10.1038/s41698-026-01303-6, PubMed 41760889
Computational Oncology research group, led by Anita Sveen
Genetics group, led by Ragnhild A. Lothe
Department of Molecular Oncology
