Molecular-guided targeted therapy with tumour necrosis factor inhibitor for the treatment of refractory paraneoplastic pemphigus

Paraneoplastic pemphigus (PNP) is a rare autoimmune blistering disorder that is often resistant to conventional immunosuppressive therapies. We report a case of refractory PNP associated with follicular dendritic cell sarcoma, in which functional T-cell analysis revealed a dominant T helper 1/T cytotoxic1 (Th1/Tc1) immune response and elevated serum tumour necrosis factor (TNF), guiding successful treatment with the TNF inhibitor etanercept. This case underscores the potential of molecular-guided therapy targeting cellular immunity in managing refractory PNP.