SummaryThe British Committee for Standards in Haematology first produced guidelines for the diagnosis and management of hairy cell leukaemia and hairy cell leukaemia variant in 2000. This revision updates those guidelines and covers the areas of diagnosis, treatment and assessment of response to therapy.

Summary. Splenic lymphoma with villous lymphocytes (SLVL) is a low-grade B-cell lymphoma defined in the World Health Organization classification as the leukaemic form of splenic marginal zone lymphoma. Presenting features and response to therapy have been described, but information on prognostic factors is scanty. Clinical, laboratory and follow-up data were collected on 129 patients with SLVL to determine features predicting disease behaviour and survival. Diagnosis was made on clinical, morphological and immunophenotypic features and, where available, bone marrow and spleen histology. Median age was 69 years (range 39-90 years) and male:female ratio, 0AE9. The majority had splenomegaly, but lymphadenopathy and hepatomegaly were rare. Median Hb was 11AE8 g/dl, white blood cell count was 16 · 10 9 /l and platelet count was 145 · 10 9 /l; 27% of patients had monoclonal protein in serum and/or urine. While 27% of patients remained untreated, 10% transformed to high-grade lymphoma. Median follow-up was 61 months and median survival was 13 years, with 72% of patients alive at 5 years. Cox regression analysis showed that increasing age, anaemia, thrombocytopenia and lymphocytosis > 16 · 10 9 /l were independent adverse predictors of overall survival. However, only anaemia and lymphocytosis > 16 · 10 9 /l remained highly significant independent prognostic factors when only deaths due to lymphoma were analysed. Splenectomized patients fared better than those receiving chemotherapy only (P ¼ 0AE001 for SLVL deaths). We conclude that SLVL is mainly a disease of the elderly with a relatively benign course but, when treatment is required, splenectomy is beneficial.

The biologic and pathologic features of B-cell malignancies bearing a translocation t(14;19)(q32;q13) leading to a fusion of IGH and BCL3 are still poorly described. Herein we report the results of a comprehensive cytogenetic, fluorescence in situ hybridization (FISH), molecular and histopathological survey of a large series of B-cell malignancies with t(14;19) or variant translocations. A total of 56 B-cell malignancies with a FISHproven BCL3 involvement were identified with the translocation partners being IGH (n ¼ 51), IGL (n ¼ 2), IGK (n ¼ 2) and a non-IG locus (n ¼ 1). Hierarchical clustering of chromosomal changes associated with the t(14;19) indicated the presence of two different groups of IG/BCL3-positive lymphatic neoplasias. The first group included 26 B-cell malignancies of various histologic subtypes containing a relatively high number of chromosomal changes and mostly mutated IgVH genes. This cluster displayed three cytogenetic branches, one with rearrangements in 7q, another with deletions in 17p and a third one with rearrangements in 1q and deletions in 6q and 13q. The second group included 19 cases, mostly diagnosed as B-cell chronic lymphocytic leukemia (B-CLL), and characterized by few additional chromosomal changes (e.g. trisomy 12) and unmutated IgVH genes. In conclusion, our study indicates that BCL3 translocations are not restricted to B-CLL but present in a heterogeneous group of B-cell malignancies.

Summary The t(14;19)(q32;q13), involving the BCL3 locus at chromosome 19q13 and the immunoglobulin heavy chain gene at 14q32, is a rare recurrent cytogenetic abnormality identified in B‐cell neoplasms, most of which have been classified as chronic lymphocytic leukaemia (CLL) in the literature. We describe the clinicopathological, immunophenotypic and cytogenetic findings in seven patients with B‐cell neoplasms associated with t(14;19)(q32;q13). There were five men and two women, with a median age of 48 years (range 33–68). All had absolute lymphocytosis, six had lymphadenopathy, and one had splenomegaly. Lymphocytes in blood and bone marrow aspirate smears were predominantly small and cytologically atypical. Flow cytometric immunophenotyping showed an atypical immunophenotype with low CLL scores. The growth pattern in bone marrow biopsy specimens was interstitial to diffuse; immunohistochemical stains were positive for bcl3 and negative for cyclin D1. Lymph node biopsy specimens of two patients revealed total architectural effacement by neoplasm with proliferation centres. In addition to t(14;19), cytogenetic studies demonstrated trisomy 12 in five patients. These results suggest that B‐cell neoplasms with the t(14;19)(q32;q13) present frequently as leukaemia composed of small B‐lymphocytes and share many features with CLL. However, these neoplasms also differ from CLL cytologically and in their immunophenotype.