Multilobated lymphoma of B cell type: a multiparameter investigation

Cutaneous spindle-cell B-cell lymphoma: a morphologic variant of cutaneous large B-cell lymphoma

The morphologic spectrum of large B-cell lymphoma is broad. Several unusual variants have been described such as lymphoma with myxoid stroma, sclerosing B-cell lymphoma, signet ring-cell lymphoma, and multilobated B-cell lymphoma among others. We report on five cases of cutaneous large B-cell lymphoma in which the neoplastic cells were spindle-shaped. In two cases, the clinical features fulfilled those of a primary cutaneous lymphoma; in the three other cases, the lymphoma most likely arose primarily in the skin, but incomplete clinical workups precluded definite categorization. The patients ranged in age from 30 to 89 years and presented with solitary lesions on the trunk or head. Histopathologic examination revealed nodular or dense diffuse infiltrates involving the entire dermis as well as the subcutaneous fat in some cases. Thickened collagen bundles between the spindled cells were present in one case. Cytomorphologic analysis showed the presence of round or oval medium-sized and large-sized lymphocytes with features of centrocytes and centroblasts in some foci, with others dominated by cells with spindle-shaped, elongated, twisted nuclei with dispersed chromatin and scant cytoplasm. Immunohistologic analysis revealed that both round or oval and spindled cells were positive for CD20 in all cases; in all cases tested, these cells were also positive for MIB-1 and were negative for CD3, CD5, CD43, CD45RO, CD21, CD30, CD68, S-100, HMB-45, actin, smooth-muscle actin, and cytokeratin. Bcl-2 was expressed in one of three cases tested. Analysis of the rearrangement of the J(H) gene by polymerase chain reaction performed in one case showed a monoclonal pattern. Spindle-cell large B-cell lymphoma represents a distinctive rare subtype of the cutaneous large B-cell lymphoma and can arise primarily in the skin in some cases. Recognition of this variant is necessary to avoid misdiagnosis of other cutaneous malignant spindle-cell tumors.

B-cell lymphoma of large multilobated type: an immunohistochemical study of 8 cases and review of the literature

Large multilobated cell lymphomas represent an heterogenous group comprising both B-cell and T-cell subtypes. The correct lineage identification of each subtype cannot be based on morphologic grounds, as it has already been stressed by other authors, and demands the use of immunophenotyping methods. In this study we review the literature and present eight new cases of large multilobated B-cell lymphoma which have been immunophenotyped in paraffin sections with a panel of monoclonal [L26 (CD20), 4KB5 (CD45R), UCHL1 (CD45RO), MT1 (CD43)] and polyclonal (anti-CD3, anti-kappa, anti-lambda) antibodies. We further investigated the expression of c-myc p62 oncoprotein and of proliferating cell nuclear antigen (PCNA) using the monoclonal antibodies c-myc 1-9E10 and PC-10 respectively. In all cases the neoplastic cells were positive for L26 (CD20) and negative for anti-CD3. Five cases were positive for 4KB5 (CD45R) while six cases stained positively for UCHL1 (CD45RO) or MT1 (CD43). Four cases were monoclonal in respect to light chain restriction. Immunoreactivity with c-myc 1-9E10 and PC-10 was observed in all cases. As far as c-myc 1-9E10 is concerned, positive cells constituted more than 45% of the neoplastic population in six cases, whereas in all cases the percentage of PC-10 positive cells was greater than 45%. The staining pattern was nuclear and/or cytoplasmic for c-myc 1-9E10 but solely nuclear for PC-10. The elevated c-myc and PCNA expression are indices of high proliferation rate in this type of lymphoma and may suggest a high malignancy grade.

Large cell, multilobated, B-cell lymphoma of the palate. A case report

A case of B-large cell non-Hodgkin's lymphoma (NHL) with multilobated nuclei arising in the palatal mucosa is described. Immunologic typing of tumor cells was crucial to determine the exact cell of origin of this lesion.

Primary gastric T-cell lymphoma with manifold histologic appearances

A rare case of malignant T-cell lymphoma with manifold histologic appearances was described. The lymphoma occurred in the stomach of a 50-year-old Japanese male. Grossly, the lymphoma exhibited a deeply ulcerated mass. Histologically, in addition to diffuse infiltrate of large lymphoid cells with deeply indented nuclei, there were many epithelioid cell granulomas, remarkable tissue eosinophilia and stromal fibrosis, mimicking inflammatory disease. Immunohistochemical studies and a gene analysis demonstrated the T-cell phenotype.