Activated pulmonary tuberculosis in a patient with melanoma during PD-1 inhibition: a case report.

Background: PD-1 checkpoint inhibitors have shown a robust tumor response in the treatment of various cancers. Pembrolizumab is an anti-PD-1 checkpoint antibody approved for the treatment of unresectable or metastatic melanoma in more than 40 countries. Although autoimmune pneumonitis is considered a common immune-related adverse event of PD-1 inhibitors, only limited studies have assessed the development of opportunistic infections such as pulmonary tuberculosis (TB).

Case presentation: A patient with metastatic melanoma whose pulmonary TB was activated after administration of pembrolizumab for melanoma is reported. Anti-TB drugs were administered, followed by pembrolizumab (2 mg/kg, repeated every 28 days), which successfully cured the TB and achieved complete response for melanoma.

Conclusion: Activated pulmonary TB was observed during the administration of pembrolizumab. It was safe and effective in the current patient to combine anti-TB drugs and PD-1 inhibitors. More importantly, screening pulmonary TB before administration of PD-1 inhibitors is recommended.