A case of Sweet's syndrome developed after the treatment of herpes simplex infection in a metastatic breast cancer patient.

Background: Sweet's syndrome or acute febrile neutrophilic dermatosis is associated with several systemic diseases such as malignancies and infectious diseases.

Methods: We present a 34-year-old woman with Sweet's syndrome associated with both herpes infection and metastatic disease.

Results: Skin biopsy showed neutrophilic infiltrates in the dermis confirming the diagnosis of Sweet's syndrome.

Conclusions: To our knowledge, this is the second case of Sweet's syndrome associated with herpes simplex infection in the literature. Further observations are required to determine the relationship between Sweet's syndrome and herpetic infection.