Sarcoidosis is a systemic granulomatous disease that affects numerous organs, 
commonly manifesting at the lungs and skin. While corticosteroids remain the 
first line of treatment, tumour necrosis factor alpha (TNF-α) inhibitors have 
been investigated as one potential steroid sparing treatment for sarcoidosis. 
TNF-α is one of many components involved in the formation of granulomas in 
sarcoidosis. While there have been larger scale studies of biologic TNF-α 
inhibition in systemic sarcoidosis, studies in cutaneous disease are limited. 
Paradoxically, in some patients treated with biologic TNF-α inhibitors for other 
diseases, treatment can induce the development of sarcoidosis. In the light of 
this complexity, we discuss the role of TNF-α in granuloma formation, the 
therapeutic role of TNF-α inhibition and immunologic abnormalities following 
treatment with these TNF-α inhibitors including drug-specific alterations 
involving interferon-γ, lymphotoxin-α, TNF receptor 2 (TNFR2) and T-regulatory 
cells.