Introduction: Sweet's syndrome, one of the neutrophilic dermatoses, is idiopathic in most cases. In 10-20% of cases it is paraneoplastic, associated with a solid tumour or haematological malignancy. An association with carcinoma of the bronchus has been only rarely described.
Case report: We report the case of a 56 year old man who presented with Sweet's syndrome two months before the diagnosis of a squamous cell carcinoma of the bronchus. The dermatosis responded well to corticosteroids. The progress of the tumour was favourable, with stabilisation following 3 courses of chemotherapy and local radiotherapy.
Discussion: This case report updates this rare association and underlines the importance of undertaking appropriate thoracic investigations in the presence of this dermatosis. A paraneoplastic secretion of interleukin-8, GM-CSF and/or G-CSF by the bronchial tumour cells facilitating the recruitment of neutrophils, particularly in the skin, may account for the pathophysiology of this condition.