Non-tropical idiopathic splenomegaly (Dacie's syndrome): report of 5 cases.

We describe 5 patients, aged 22-69 years, with massive splenomegaly of unknown origin an features of hypersplenism. Splenectomy corrected the cytopenia(s) and abolished the symptoms in each case; the histological features of the spleen were non-specific and included congestive changes and lymphoid hyperplasia. 2 of these patients developed non-Hodgkin's lymphoma (NHL) 2 and 6 years after spenectomy. A total of 46 cases of splenomegaly of unknown origin have been reported from UK, USA, and Australia so far, and in 9, NHL developed 8 to 80 months after splenectomy. The questions relating to the pathogenesis of splenomegaly and the subsequent development of NHL remain to be answered. We propose that this 'entity' be known as Dacie's syndrome, after Sir John Dacie who characterised it in 1969.