[A chancre instead of cancer]

Syphilis (lues) is a sexually transmitted infection caused by the spirochete Treponema pallidum. In adolescents, the diagnosis of primary syphilis can be made promptly by taking a sexual medical history and inspecting the glans penis.

A 17-year-old male was referred to the paediatric oncology centre for additional diagnostics due to inguinal lymphadenopathy, with a strong suspicion of a malignant lymphoma. None of the physicians took a sexual medical history or investigated the glans penis, as a result of which essential information was lacking. The combination of inguinal lymphadenopathy and the ultrasound findings for the inguinal region made the physicians only consider a malignancy. However, it actually concerned a reactive lymphadenopathy associated with primary syphilis.

This case demonstrates that a full medical history and thorough physical examination can prevent the need for costly and invasive diagnostics.