CD27 distinguishes two phases in bone marrow infiltration of splenic marginal zone lymphoma

The Relevance of Additional Immunohistochemical Markers on the Differential Diagnosis of Small B-Cell Lymphomas: A Case-control Study

Objective:

Clinical and pathological differential diagnosis of small B-cell lymphomas (SBCLs) is still controversial and may be difficult due to their overlapping morphology, phenotype, and differentiation to plasma cells. We aimed to examine the expression of the immune receptor translocation-associated protein 1 (IRTA1), myeloid cell nuclear differentiation antigen (MNDA), lymphoid enhancer-binding factor-1 (LEF1), and stathmin 1 (STMN1) markers in SBCL cases involving different sites that may have plasma cell differentiation.

Materials and Methods:

We studied 154 tissue samples with lymphoma involvement from 116 patients and evaluated the staining distribution of the markers. Expressions were evaluated in 21 chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), 7 follicular lymphoma (FL), 14 nodal marginal zone lymphoma, 17 extranodal marginal zone lymphoma, 55 splenic marginal zone lymphoma, 22 marginal zone lymphoma-not otherwise specified, and 18 lymphoplasmacytic lymphoma/Waldenström macroglobulinemia cases by immunohistochemistry.

Results:

The results confirmed that LEF1 was the most sensitive and specific marker for CLL/SLL and STMN1 was the most sensitive and specific marker for FL (p<0.001). MNDA and IRTA1 were useful markers to distinguish marginal zone lymphomas.

Conclusion:

Our results suggest that LEF1 for CLL/SLL and STMN1 for FL are reliable markers. LEF1, MNDA, STMN1, and IRTA1 are helpful with other routinely used immunohistochemical markers in a diagnostic algorithm considering their limitations.

Gastrointestinal follicular lymphoma: Current knowledge and future challenges

The gastrointestinal (GI) tract is the most commonly involved site of extranodal follicular lymphoma (FL). GI-FL shows very indolent clinical behavior and localized at GI tract without any progression or transformation compared to nodal FL. The most frequently involved site of the GI tract was the duodenum followed by the jejunum and ileum, and only 15% of FL arising in the second part of the duodenum were localized there without scattered very small daughter lesions in other GI tract examined by double-balloon endoscopy. The typical macroscopic appearance of GI-FL was multiple white nodules. Microscopically, neoplastic cells were small- to medium-sized lymphoid cells and formed neoplastic follicles. Most of the cases (>95%) were histologically Grade 1 to 2 (low grade). Several pathological and molecular characteristics were seen in GI-FL (especially duodenal FL) compared with nodal FL: immunoglobulin heavy chain deviation to VH4 and VH5; memory B-cell immunophenotype; and molecular features shared by mucosa-associated lymphoid tissue lymphoma. Considering the pathological and molecular uniqueness of this disease, GI-FL should be separately managed from nodal FL.

Immunophenotypic profile and role of adhesion molecules in splenic marginal zone lymphoma with bone marrow involvement

Splenic Marginal Zone Lymphoma (SMZL), with or without villous lymphocytes (VL+/-), is a low-grade lymphoproliferative disorder with constant involvement of the bone marrow (BM). Different BM infiltration patterns, mainly intra-sinusoidal, interstitial and nodular, have been described. Adhesion molecules (AMs) constitute a heterogeneous group of antigenic receptors playing a major role in leukocyte recruitment, in lymphocyte homing and in cellular-mediated immune response. Evolution and pattern of the BM infiltrate could be influenced by a variable expression of AM on SMZL lymphocytes. The degree and pattern of BM infiltration and the immunohistochemical expression of AM (H-CAM, BL-CAM, L-selectin, PSGL-1, E-selectin, ICAM-1, VCAM-1 and Beta-1 integrin) among the different infiltration patterns were evaluated in BM biopsies of 38 patients with SMZL and graded according to a semi-quantitative score ranging from 0-4 and based on the percentage of positive cells. An intra-sinusoidal infiltration was constantly observed, alone or in conjunction with other patterns. H-CAM and BL-CAM showed a moderate-to-high degree of positivity in the intra-sinusoidal infiltrate (median expression grade-3) and were expressed in the neoplastic lymphocytes independently from the pattern. PSGL-1 was mostly expressed in the perisinusoidal region and in case of interstitial infiltration (grade-2). ICAM-1 and VCAM-1 were selectively expressed in the nodules as a reticular meshwork located in the core region (grade-2); VCAM-1 was also expressed in the perinodular endothelia. E-selectin, L-selectin and beta-1 integrin proved constantly negative. These data suggest that different expression of AM can influence the modality of BM infiltration in SMZL.

Deoxycoformycin (pentostatin) in the treatment of splenic marginal zone lymphoma (SMZL) with or without villous lymphocytes

BACKGROUND

Splenic marginal zone lymphoma (SMZL) is an infrequent B-cell neoplasm that pursues an indolent course. Signs and symptoms, mostly related to hypersplenism, are successfully managed by splenectomy. However, the therapy of patients who are not fit for a surgical procedure or who relapse after splenectomy, is still an unsettled issue.

PATIENTS AND METHODS

We report a phase-II study on 16 patients with SMZL, three therapy naïve and 13 pretreated, all showing systemic symptoms or progressive worsening of peripheral cytopenia, who were treated with pentostatin at a dose of 4 mg/m2 every other week for 6-10 wk. In relapsed patients, the median interval between diagnosis and treatment was 26 month (range: 8-49).

RESULTS

Overall, 68% of the patients showed a clinical response. Two out three patients, who received pentostatin as first line therapy, attained a complete response (CR). One CR and seven minor or good haematological responses were recorded in relapsed patients. Treatment toxicity, mostly haematological, proved manageable. With a median follow-up of 35 month the median overall survival (OS) is 40 month and the median progression free survival (PFS) is 18 month.

CONCLUSION

Our data show that pentostatin administered every other week has a good degree of activity in the treatment of SMZL and suggest that this schedule could be considered a possible therapeutic option for patients who are not fit for splenectomy or have relapsed.