Integrated Immune and Molecular Profiling Identifies Prognostic Subgroups and Therapeutic Targets in Chondrosarcoma

Area of Science:

• Oncology
• Immunology
• Genetics

Background:

• Chondrosarcoma (ChS) is a rare, heterogeneous bone cancer with unknown molecular and immunological underpinnings.
• Currently, no effective systemic treatments exist for advanced ChS patients.

Purpose of the Study:

• To create an immune-mutational classification for ChS.
• To identify novel prognostic factors and molecular targets for ChS treatment.

Main Methods:

• Immunological-molecular profiling of 99 primary ChS patients (G1-G3 and dedifferentiated).
• Assessed 20 immune response markers via IHC and performed targeted next-generation sequencing of 409 genes.
• Correlated immune and mutational profiles with overall survival using a multivariate Cox model.

Main Results:

• Identified three immunophenotypes: 'cold' (IMP1), 'hot' (IMP2), and 'intermediate' (IMP3). IMP1 was common in G1, IMP2 in dedifferentiated ChS.
• IDH1/2 or TP53 mutations were linked to high-grade ChS.
• IMP2 tumors showed more immune infiltrates; IDH1 mutations were frequent in IMP2 cases.
• Tumor size, dedifferentiated subtype, IDH1 mutation, and IMP2 were independent negative prognostic factors.

Conclusions:

• Proposed an immune-mutational classification system for ChS.
• This system could help identify patients suitable for immunotherapy combined with IDH-mutant inhibitors in future clinical trials.