Surgical indications in idiopathic splenomegaly.

HYPOTHESIS The incidence of primary lymphoma of the spleen in patients with idiopathic splenomegaly is significant. DESIGN Retrospective review of all patients referred to a general surgical service for splenectomy. SETTING A large tertiary care hospital. PATIENTS Between 1994 and 2001, 86 nontrauma patients were referred for splenectomy. Of these, 18 had idiopathic splenomegaly despite prior workup with computed tomography, peripheral smear, bone marrow biopsy, and laboratory testing. All patients were symptomatic and displayed varying degrees of cytopenia. INTERVENTION All 18 patients underwent open splenectomy for diagnosis and treatment of their cytopenias. MAIN OUTCOME MEASURE Incidence of lymphoma in the pathologic specimens. RESULTS The mean size of the spleens was 21 cm (range, 14-34 cm) and mean weight was 996 g (range, 320-1840 g). In all 18 patients, the surgical specimen provided a diagnosis. Sarcoidosis was discovered in 4 patients, and 1 patient had Castleman disease. Six patients with the benign diagnosis of hypersplenism received no further interventions, and the cytopenias resolved in all 6 cases. The 7 remaining patients (39%) were diagnosed with lymphoma. Five had marginal zone lymphoma, and 2 had a more aggressive B-cell lymphoma. Three patients required chemotherapy, but 4 are still in remission since their splenectomies and show no evidence of active disease. The mean follow-up was 20 months. CONCLUSIONS A high percentage of patients with splenomegaly of unknown etiology will have primary lymphoma of the spleen. Splenectomy is both diagnostic and therapeutic and should be considered for all patients with idiopathic splenomegaly.