Transitional cell carcinoma in a patient with X-linked hyperimmunoglobulin M syndrome

Patients with X-linked hyperimmunoglobulin M syndrome (XHIGM) have a defective CD40-CD40 ligand system and further immunoglobulin class-switching. They may present with recurrent infection and malignancy involving the liver, pancreas or biliary tract. We report here a case of poorly differentiated transitional cell carcinoma in a young man with XHIGM even on regular treatment and discuss the possible pathogenesis. Given that the triggering of the CD40-CD40 ligand system has been found to improve tumor immunogenicity in recent studies, future immunotherapy targeting the CD40 ligand for these patients may be feasible to prolong their survival.