[Thoracic manifestations of Castleman's disease].

Introduction: Castleman's disease is a rare orphan disease. The prevalence is estimated at less than 1/100 000. Respirologists may encounter this disease when its thoracic manifestations occur.

Case Report: The authors report two cases of Castleman's disease with two different thoracic involvements. The first patient was a 20-year-old man without a previous medical history. A chance chest X-ray revealed right basal opacity. A lung biopsy demonstrated giant lymph node polyclonal hyperplasia leading to the diagnosis of a thoracic form of Castleman's disease. Since the patient was completely symptom free, no treatment was proposed. The patient was stable after 10months of medical supervision. The second patient, a 34-year-old woman, had a medical history of myasthenia gravis, autoimmune thrombopenic purpura and haemolytic anaemia. Her general condition deteriorated and upper mediastinal enlargement was noted. A diagnosis of multicentric Castleman's disease was established by means of the biopsy of an axillary lymph node. As the symptoms persisted, she was treated by rituximab. The clinical response was dramatic.

Conclusion: The authors call to mind the difficult diagnostic features and therapeutic strategies of Castleman's disease, a rare disease which may involve the thorax.