Acrokeratosis paraneoplastica (Bazex syndrome) - a systematic review on risk factors, diagnosis, prognosis and management.

Acrokeratosis paraneoplastica Bazex (Bazex syndrome) is a rare paraneoplastic skin disease defined by erythematous, violaceous, scaly plaques on the hands and feet and on other acral locations such as nose and ears. Bazex syndrome is linked to a variety of underlying malignancies. Usually the skin lesions develop prior to the diagnosis of an internal malignant neoplasm with spontaneous remission after tumour removal. The objective of this study was to review the so far reported risk factors, diagnostic work-up, prognosis and treatment options for Bazex syndrome in a systematic manner. This systematic review is based on a search in MEDLINE, EMBASE and Cochrane Central Register for English and German articles from 1990 to 2015. Evidence on the diagnosis and treatment of Bazex syndrome is limited predominately to case reports or to small case series. There are no randomized controlled trials. A number of underlying tumour entities, predominately oropharyngeal neoplasms and tumours of the gastroenterological tract, but other malignancies were reported. Treatment modalities including topical and systemic corticosteroids, salicylic acid, topical vitamin D analogues, etretinate and PUVA therapy are often ineffective. Due to the small number of patients and the frequent misdiagnosis of this clinical entity, the aim of this systematic review was to call attention to this rare condition and to help clinicians to diagnose and treat Bazex syndrome effectively. Because of the good prognosis of the skin lesions and the tendency to resolve spontaneously if the underlying tumour is treated early, the differential diagnosis of Bazex syndrome should be taken into consideration when dealing with atypical psoriasiform cutaneous lesions. An early diagnosis may improve the patient's prognosis substantially.