Splenic small B-cell lymphoma with predominant red pulp involvement: a diffuse variant of splenic marginal zone lymphoma?

• Published in: Histopathology Vol. 40; no. 1; pp. 22 - 30
• Main Authors: Mollejo, M, Algara, P, Mateo, M S, Sánchez-Beato, M, Lloret, E, Medina, M T, Piris, M A
• Format: Journal Article
• Language: English
• Published: Oxford UK Blackwell Science Ltd 01.01.2002; Blackwell
• Subjects: Aged; Biological and medical sciences; diffuse; DNA Mutational Analysis; DNA, Neoplasm - analysis; Female; Genes, p53 - genetics; Hematologic and hematopoietic diseases; Humans; Immunoenzyme Techniques; Leukemia, Lymphocytic, Chronic, B-Cell - chemistry; Leukemia, Lymphocytic, Chronic, B-Cell - genetics; Leukemia, Lymphocytic, Chronic, B-Cell - pathology; Leukemias. Malignant lymphomas. Malignant reticulosis. Myelofibrosis; lymphoma; Male; marginal; Medical sciences; Mutation; spleen; Splenic Neoplasms - chemistry; Splenic Neoplasms - genetics; Splenic Neoplasms - pathology; Tumor Suppressor Protein p53 - analysis; Tumor Suppressor Protein p53 - genetics; Human; Immunohistochemistry; Spleen; Process variant; Splenic disease; Marginal zone lymphoma; Malignant hemopathy; B-Lymphocyte; Non Hodgkin lymphoma; Case study; Pathology; TP53 Gene; Lymphoproliferative syndrome; Adult; Molecular biology; Elderly; Tumor suppressor gene
• ISSN: 0309-0167; 1365-2559
• DOI: 10.1046/j.1365-2559.2002.01314.x

Splenic small B‐cell lymphoma with predominant red pulp involvement: a diffuse variant of splenic marginal zone lymphoma? Aims: Splenic marginal zone lymphoma (SMZL) has been characterized by a micronodular pattern of infiltration, biphasic cytology, follicular replacement and the presence of marginal zone differentiation. Here we describe four cases with some distinctive features, such as diffuse splenic infiltration, lack of micronodules, marginal zone cytology, p53 inactivation and cutaneous involvement. Methods and results: In the course of a review of cases of SMZL, we recognized the existence of a subset of four cases of splenic B‐cell lymphoma, with predominantly red pulp involvement, absence of follicular replacement, and a monomorphous population of tumoral cells resembling marginal zone B‐cells, with scattered nucleolated blast cells. The immunophenotype (bcl2+, CD5−, CD10−, CD43−, CD23−, cyclin D1−, IgD− (3/4)) was consistent with SMZL. Bone marrow infiltration (4/4) and peripheral blood involvement (2/4) showed similar findings to those described for SMZL in these locations. However, unlike classical SMZL, 2/4 had cutaneous involvement, and 4/4 cases showed either p53 mutation or anomalous p53 staining (p53+, p21−). Conclusions: In spite of a diffuse pattern of splenic infiltration, cutaneous involvement and p53 alterations, these cases have findings that overlap with those corresponding to classic SMZL (symptomatology, morphology of bone marrow, lymph nodes, peripheral blood involvement, and immunophenotype). We suggest that these cases be considered a putative variant of SMZL.