The incidental finding of an isolated splenomegaly during clinical assessment of patients evaluated for unrelated causes has become increasingly frequent because of the widespread use of imaging. Therefore, the challenging approach to the differential diagnosis of spleen disorders has emerged as a rather common issue of clinical practice. A true diagnostic dilemma hides in distinguishing pathologic conditions primarily involving the spleen from those in which splenomegaly presents as an epiphenomenon of hepatic or systemic diseases. Among the causes of isolated splenomegaly, lymphoid malignancies account for a relevant, yet probably underestimated, number of cases. Splenic lymphomas constitute a wide and heterogeneous array of diseases, whose clinical behavior spans from indolent to highly aggressive. Such a clinical heterogeneity is paralleled by the high degree of biologic variation in the lymphoid populations from which they originate. Nevertheless, the presenting clinical, laboratory, and pathologic features of these diseases often display significant overlaps. In this manuscript, we present our approach to the diagnosis and treatment of these rare lymphomas, whose complexity has been so far determined by the lack of prospectively validated prognostic systems, treatment strategies, and response criteria.

Rituximab® provides high response rates and effective disease palliation in patients with splenic marginal zone lymphoma (SMZL). We conducted a phase II trial in patients with SMZL who were either untreated or were splenectomized but had shown disease progression within 1 year after splenectomy. Treatment consisted of six courses of Rituximab with cyclophosphamide, vincristine, non-pegylated liposomal doxorubicin and prednisone (R-COMP). Fifty-one patients were eligible for the analysis. The overall response rate was 84%. The 6-year progression-free survival and overall survival were 54% and 72%, respectively. Toxicity was substantial (grade≥3 neutropenia: 26%; grade≥3 infections: 8%). Of the 15 deaths, two occurred on treatment (one sepsis and one pneumonia). Six deaths were due to lymphoma progression, four to secondary neoplasia, one to sepsis, one to pneumonia and one to splenectomy complications. R-COMP should be restricted to patients with bulky disease associated with symptoms or to patients with possible histological transformation.

Until now, literature data support the fact that the CHOP regimen represents the standard first line treatment for patients with advanced intermediate-grade non-Hodgkin's lymphoma. Recently, idarubicin has been introduced in clinical trials because of its favourable preclinical profile: it is more active than daunorubicin and doxorubicin against a number of experimental tumour systems and is significantly less cardiotoxic in animal models. From March 1991 to June 1993, 115 previously untreated patients with stage II to IV intermediate-grade non-Hodgkin's lymphoma, according to the Kiel classification, were enrolled in a phase III comparative trial. The objectives of the study were to compare the efficacy and safety of using idarubicin instead of doxorubicin in the polychemotherapeutic regimen CHOP (cyclophosphamide, doxorubicin, vincristine, and dexamethasone). Of the 115 patients registered for the trial, 103 were evaluable: 52 received CH (doxorubicin)OP and 51 received CI(Idarubicin)OP. Known prognostic factors were equally distributed among the two groups. There were no significant differences between the 2 groups in the rates of partial and complete response. The overall response rate was 87%, with complete response in 62%: 63% in the CHOP group, and 59% in the CIOP group. At 30 months (median 20 months), 86% of all CR patients were alive without disease in the CHOP group and 85% in the CIOP group. Patients treated with CHOP experienced severe alopecia more frequently (P = .004). Only three patients in the CIOP group showed cardiac adverse events (1 moderate and 2 mild), while in the CHOP group 4 mild, 2 moderate and 1 severe were recorded. LVEF monitoring was carried out in 31 patients of the CHOP group and in 27 of the CIOP group. A median drop of 8.3% of the LVEF was observed in patients treated with CHOP regimen as compared to 4.8% in patients with CIOP regimen (P = .0001). In this trial, the "idarubicin arm" (CIOP regimen) was found to have an equivalent therapeutic efficacy and, slightly, reduced clinical toxicity in comparison to the standard doxorubicin-containing CHOP regimen in patients with intermediate-grade non-Hodgkin's lymphoma.

Waldenström's macroglobulinemia (WM) is an incurable disorder of B cells. Following occasional reports of response to alpha interferon (IFN) and in view of its effectiveness in hairy cell leukemia, we tested this agent in a relatively large group (n = 88) of patients who had an IgM monoclonal component (MC) greater than 10 g/l. Thirty eight patients had a MC > 30 g/l and were classified as Waldenström's macroglobulinemia (WM), while fifty had either WM in an early stage or an IgM monoclonal gammopathy of undeterminated significance (all of them operationally classified as IgM-MGUS). All patients received IFN 3 MU/day for one month and then 3 times/week. Response to treatment was mainly based on MC reduction in two consecutive determinations (> 50%: major response; 25-50%: minor response). Of 36 evaluable WM patients, 12 had a major and 6 a minor response; of 41 evaluable IgM-MGUS patients, 2 had a major and 6 a minor response. In WM patients with a major response, MC reduction was associated with disappearance of hyperviscosity symptoms, raised Hb level and reduced bone marrow lymphoplasmacytosis. At the dose used, tolerance was excellent in the majority of patients; only 15% withdrew from the study due to side effects. Although single cases and very small series have already been reported, no large study collecting quantitative data on the effects of alpha IFN in WM has been published so far. Our results suggest that IFN treatment is not indicated for patients with a low monoclonal component, while it is of clinical benefit in about 50% of patients with IgM > 30 g/l.