Tertiary syphilis mimicking metastatic rectal cancer.

Syphilis is a sexually transmitted infection caused by the bacterium Treponema pallidum. Tertiary syphilis, a late-stage multi-visceral complication of the disease is characterized by its diversity of clinical manifestations. Here, we present the first documented case of tertiary syphilis that clinically and radiologically mimicked primary rectal cancer with hepatic metastasis.