Felty Syndrome-Associated Clonal Cytotoxic T-Cell Disease With Terminal Aggressive Progression: Shared STAT3 and TET2 Mutations Across a Prolonged Disease Course.

INTRODUCTION

Biological overlap between Felty syndrome (FS) and clonal cytotoxic T-cell disorders is increasingly recognized, but aggressive progression is uncommon.

METHODS

We investigated an autopsy-confirmed case of terminal aggressive clonal T-cell disease that developed after a 4-year clinical course diagnosed as FS using serial immunophenotypic and molecular analyses.

RESULTS

Evolving γδ T-cell populations, TCR clonality, shared STAT3 and TET2 mutations, and a newly emergent complex karyotype supported clonal continuity and terminal aggressive progression.

CONCLUSION

This case provides clinicopathological evidence of long-term evolution in FS-associated clonal cytotoxic T-cell disease.

TRIAL REGISTRATION: The authors have confirmed clinical trial registration is not needed for this submission.