B-zone small lymphocytic lymphoma: a morphologic, immunophenotypic, and clinical study with comparison to "well-differentiated" lymphocytic disorders.

The pathologic, immunologic, and clinical features of five cases of B-zone small lymphocytic lymphoma (BZSLL), characterized by a nondestructive growth pattern with a selective and complete replacement of the B-zone areas of lymph nodes, were examined. These findings were compared with those of 13 cases of intermediate differentiated lymphoma/mantle zone lymphoma (ILL/MZL) and 20 cases of typical small lymphocytic lymphoma/chronic lymphocytic leukemia (SLL/CLL). B-zone SLL was characterized histologically by a deceptively benign pattern at a low magnification, the lymph node architecture being substantially preserved, in contrast to the ILL/MZL and SLL/CLL cases, in which complete effacement of the normal architecture usually could be observed. Moreover, in BZSLL the cellular population was rather uniform and lacked either a prolymphocytic component or the small-cleaved lymphoid cells often seen in SLL/CLL and ILL/MZL cases, respectively. The phenotypic profile of the BZSLL clonal cell population studied by the immunoperoxidase method and by single- and double-labeling flow cytometric analyses (SIg+, CD19+, CD20+, CD21+, CD22+, CD24+, CD35+, CD37+, CD74+, CD45+, CD45R+, MB2+, HLA-DR+, Leu-8+, CD9+/-, CDw75+/-, CD5-/+, CD23-/+, CD10-, FMC7-, PCA-1-, CD25-, CD38-, CD43-, CD3-) appeared to be fairly homogeneous and sufficiently distinct from that of ILL/MZL, based on the absence of FMC7 and CD38 molecules, and from that of SLL/CLL due to significantly stronger expression of SIgs (P less than .05), the higher reactivity with anti-CD9 and -CD22 antibodies (P less than .05), the lower reactivity with anti-CD5 and -CD23 antibodies (P less than .05), and the absence of CD25 determinants. Several clinical features of patients with BZSLL, including age group, advanced stage disease, and high frequency of bone marrow and peripheral blood involvement, were similar to those found in the other patients with ILL/MZL and SLL/CLL, but none of the BZSLL patients had an absolute lymphocyte count higher than 15.0 x 10(9)/L at presentation. Based on the architectural pattern, cytologic features, immunophenotypes, and hematologic findings, we conclude that BZSLL is an unusual variant of SLL that is primary in the lymph nodes and should be distinguished from ILL/MZL and CLL.     

Immunoarchitecture of the "pseudofollicles" of well-differentiated (small) lymphocytic lymphoma: a comparison with true follicles

Some human malignant lymphomas of the B-cell type have morphologic and immunologic similarities to follicles seen in nonneoplastic reactive lymph nodes. In contrast, a peculiar, vaguely nodular pattern of growth called "pseudonodules" or "pseudofollicular proliferation centers," which is morphologically distinguishable from "true" follicles, is seen in malignant lymphoma, well-differentiated (small) lymphocytic type (WDL). To characterize the cellular components of "pseudofollicles," we undertook a detailed, comparative immunohistologic study of the architectural relationship and distribution of T cells, B cells, and follicular dendritic reticulum cells (DRCs) in reactive follicles, neoplastic follicles, and pseudofollicles. We report several observations on the presence of DRCs and T-cell subset topography in pseudofollicles. Immunohistologic staining for the C3d complement receptor on DRCs revealed that DRC networks associated with "true" follicles were present in all cases of reactive follicular hyperplasia (RFH) and malignant lymphoma, nodular, poorly differentiated lymphocytic type (PDL) studied. Surprisingly, DRC networks were also identified in 8 of 23 cases of WDL. Although the size distribution of DRC network diameters was nearly identical in RFH and PDL, the sizes were markedly diminished in WDL. Immunohistologic staining for Leu 3+ and Leu 2+ T-cell subsets confirmed cellular arrangements in RFH and PDL reported by others. In only 2 of 23 cases of WDL could T cells localized to "pseudofollicles" in frozen tissue sections be identified in a nonrandom arrangement.     

Intermediate lymphocytic lymphoma: an immunophenotypic study with comparison to small lymphocytic lymphoma and diffuse small cleaved cell lymphoma

Sixteen cases of intermediate lymphocytic lymphoma (ILL), including eight cases with mantle zone architecture, were studied using cryostat sections, a biotin-avidin immunoperoxidase technique, and a large panel of monoclonal antibodies. The neoplastic cells invariably expressed IgM, most B lineage antigens (B1, TO15, Leu-12, 6A4, 41H, BA-1, and LN-2), and Ia. IgD was expressed in 12 cases. Leu-1 and Leu-8 were weakly expressed by the tumor cells in 12 and 11 cases, respectively. The neoplastic cells did not express common acute lymphoblastic leukemia antigen (CALLA) or the T10 antigen in any case. Because ILL is difficult to differentiate from small lymphocytic lymphoma (SLL) and diffuse small cleaved cell lymphoma (DSCCL) on the basis of light microscopic criteria, the immunologic findings of ILL were compared to 31 cases of B cell SLL and 11 cases of B cell DSCCL previously studied in the laboratory to determine if immunologic findings might aid in the distinction. No absolute, and five statistically significant, differences were found; IgD in combination with IgM was seen more commonly in cases of ILL and DSCCL than in SLL (P less than .01), IgG was found more often in SLL than in ILL and DSCCL (P less than .05), Leu-8 was more commonly expressed in ILL and SLL than in DSCCL (P less than .05), T9 expression was less frequent in ILL as compared with SLL (P less than .05) and more proliferating cells were seen in ILL and DSCCL than in SLL (P less than .01). The investigators conclude that these three classes of lymphoma are remarkable much more for their immunologic similarities than for their differences and that immunologic studies are of limited usefulness in differentiating the three neoplasms. Their results also support the concept that these lymphomas are closely related to each other. In particular, DSCCL immunologically appears to be more closely related to SLL and ILL than to follicular small cleaved cell lymphoma.     

Indolent systemic mastocytosis associated with atypical small lymphocytic lymphoma: a rare form of concomitant lymphoproliferative disease

Patients with systemic mastocytosis (SM) may acquire an associated hematologic non-mast cell (MC)-lineage disease (AHNMD). In most cases, a myeloid neoplasm is diagnosed, whereas the occurrence of a lymphoproliferative disease is an extremely rare event. We report on a patient with indolent SM associated with small lymphocytic lymphoma (SLL). The patient presented with lymphadenopathy, maculopapular exanthema, and elevated serum tryptase. The bone marrow biopsy showed focal MC aggregates together with SLL. As assessed by immunostaining, neoplastic MC were found to exhibit CD117 and CD25 but did not display CD5 or CD20, whereas SLL cells were found to coexpress CD5 and CD20 but did not express MC antigens. The KIT mutation D816V was detected in sorted CD34(+) cells and unfractionated marrow cells but not in CD5(+) SLL cells, confirming the coexistence of 2 distinct neoplasms.     

Chronic lymphocytic leukemia/small lymphocytic lymphoma associated with IgM paraprotein

We studied the clinicopathologic, immunophenotypic, and cytogenetic features of 26 patients with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) associated with serum IgM paraprotein. The study group (16 men; 10 women; median age, 64 years; range, 40-82 years) represents approximately 2.5% of CLL/SLL cases at our institution. The paraprotein level ranged from 1 to 14 g/L (median, 4 g/L). Neoplasms in bone marrow were composed of small round lymphocytes arranged in nodular (n = 6), diffuse (n = 5), interstitial (n = 5), or mixed (n = 10) patterns. All cases were positive for monotypic surface immunoglobulin light chain, IgM/IgD, CD5, CD19, CD20, and CD23. CD11c (14/20 [70%]), CD79b (11/19 [58%]), FMC-7 (11/26 [42%]), CD22 (8/20 [40%]), and ZAP-70 (6/19 [32%]) were expressed in subsets of cases. Of 17 bone marrow specimens assessed by conventional cytogenetics, 6 were abnormal and 11 were diploid. The overall survival of this group (median follow-up, 24 months) was not significantly different from that for an age-, sex-and stage-matched group of 52 CLL/SLL patients without IgM paraprotein (P = .60). We conclude that CLL/SLL cases with serum IgM paraprotein are similar to other CLL/SLL cases in their clinicopathologic and immunophenotypic features.     

Methotrexate-associated lymphoproliferative disorders mimicking angioimmunoblastic T-cell lymphoma

Patients affected by autoimmune diseases (rheumatoid arthritis (RA), psoriasis, and dermatomyositis) treated with methotrexate (MTX) develop lymphoproliferative disorders (LPDs). These cases have been reported to be diffuse large B-cell lymphoma, Hodgkin lymphoma, or polymorphous post-transplant LPDs. However, angioimmunoblastic T-cell lymphoma (AITL) is extremely rare in the medical literature. In this report, we describe three cases of RA patients who developed MTX-associated LPDs resembling AITL. They developed systemic lymph node swelling after initiation of MTX. The affected lymph nodes showed the histological finding of AITL: polymorphous infiltrates, mainly T-cells and arborizing high endothelial venules. Two cases showed a predominance of CD4-positive cells in proliferative T-cells, whereas the third case showed CD8-positive cells. CD10 was negative in all cases. RNA in situ hybridization of Epstein-Barr virus (EBV) demonstrated EBV-positive B-cells to be scattered in two cases, but not in one case. The lymphoadenopathy spontaneously regressed with cessation of MTX in all three cases, but one case recurred. These are interesting cases of MTX-associated LPDs mimicking AITL, and cessation of MTX is the only cure for patients with MTX-associated LPDs resembling AITL.     

Epstein-Barr virus-associated B-cell lymphoproliferative disorders in angloimmunoblastic T-cell lymphoma and peripheral T-cell lymphoma, unspecified

Various patterns of Epstein-Barr virus (EBV)-associated B-cell lymphoproliferation occur in patients with immunodeficiency. We studied 17 cases of T-cell lymphoma displaying extensive EBV-driven B-cell lymphoproliferation or simultaneous/subsequent EBV-associated B-cell lymphoma. In 10 cases of angioimmunoblastic T-cell lymphoma, an uncommonly prominent population of EBV+ atypical, activated, focally confluent large transformed B cells was found in the background of T-cell lymphoma. In 4 cases, an EBV-associated B-cell neoplasm (3 diffuse large B-cell lymphomas, 1 plasmacytoma) occurred in patients with T-cell lymphoma. Three cases were composite lymphomas of a peripheral T-cell lymphoma, unspecified, combined with EBV-associated diffuse large B-cell lymphoma. The transformed B-cell population displayed EBV latency types 2 and 3. Monoclonal and oligoclonal B-cell populations were detected in 5 and 6 cases, respectively. Similar to other states of immunodeficiency, disease-related and therapy-induced immunosuppression in T-cell lymphoma may lead to a prominent EBV-associated B-cell lymphoproliferation and to EBV+ B-cell neoplasms.     

Necrotizing granulomas in B-cell chronic lymphocytic leukemia/small lymphocytic lymphoma

We present three cases of patients with B-cell small lymphocytic lymphoma/chronic lymphocytic leukemia that were retrieved from our files during a period of 11 months and who suddenly developed lymphadenopathy. Clinically, this lymphadenopathy was thought to represent a manifestation of their background disease and, for this reason, no cultures were performed on fresh tissue. However, histologic studies in all cases showed necrotizing granulomas. When results of our special stains were negative, we submitted the specimens for molecular studies, which demonstrated the presence of tuberculous bacilli in two out of three cases. We believe that tuberculosis can present as a sudden lymphadenopathy in immunocompromised people and we would like to raise the awareness among the clinicians and nursing and pathology laboratory staff about the risks of handling these specimens without proper precautions. Also, we emphasize the fact that, in some cases, tuberculous bacilli cases may need molecular studies to be demonstrated.     

Lymphocyte nuclear morphology in diffuse well-differentiated lymphocytic lymphoma. Comparative morphometry of normal lymphoid tissues, non-Hodgkin's lymphoma, and Hodgkin's disease

Precise morphologic data on the relationship of diffuse well-differentiated lymphocytic lymphoma (DWDLL) to other non-Hodgkin's lymphomas (NHLs) are lacking in current classifications of lymphomas. Morphometry of plastic-embedded tissues describes details of the mean nuclear parameters and distribution of lymphocyte-types in 14 cases of DWDLL in nodal and extranodal sites. The results indicate that the proportion of small (unstimulated or nontransformed) lymphocytes in DWDLL varies from 50% to 86%. The mean nuclear area of small lymphocytes in DWDLL is either within the size range or somewhat smaller, and many examples are more irregular in shape, than the small lymphocytes in germinal centers that are morphologically comparable with the majority of lymphocytes in DWDLL and mantle zones. The morphologic relationship of DWDLL to other NHLs, Hodgkin's disease, and paracortical, mantle, and germinal center lymphocytes in lymphoid-reactive hyperplasia was established by morphometric analysis of the nuclear profiles of small lymphocytes. The small (nontransformed) lymphocytes in those subtypes of NHL other than DWDLL have abnormally small and more irregular nuclear profiles than those in normal small lymphocytes, or the small-lymphocyte population of Hodgkin's disease. Such findings may be of diagnostic significance to pathologists.     

Fine-needle aspiration biopsy findings in patients with small lymphocytic lymphoma transformed to hodgkin lymphoma

Although small lymphocytic lymphoma (SLL) is an indolent lymphoma, approximately 5% of cases can transform to a higher-grade lymphoma, rarely Hodgkin lymphoma (HL). We report the fine-needle aspiration (FNA) results of 6 cases of SLL/chronic lymphocytic leukemia (CLL) that transformed to HL. FNA findings were correlated with the histologic features and clinical follow-up. The patients included 5 men and 1 woman, ranging in age from 49 to 72 years at the time of SLL/CLL diagnosis with time for development of HL ranging from 0 to 95 months (mean, 49.3 months). The FNA diagnoses were SLL with HL transformation (2 cases), SLL with large atypical cells (1 case), and atypical lymphoid proliferation with large atypical cells (3 cases). Flow cytometry performed in 5 cases (2 FNA specimens) demonstrated a monoclonal B-cell population with CD19/CD5 coexpression.The presence of large atypical mononucleated and binucleated cells in lymph node FNA specimens from patients with SLL/CLL with progressive adenopathy should raise the possibility of transformation to HL. In these cases, histologic confirmation is always recommended, not only to differentiate HL transformation from other entities but also for subclassification of HL.     

Phenotypic heterogeneity of B cells in patients with chronic lymphocytic leukemia/small lymphocytic lymphoma

Although some studies have examined the expression of aberrant markers such as CD2, CD7, CD10, CD13, CD33, and CD34 on B cells in chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), a uniform multiparametric analysis of the frequency of expression of these markers using stringent criteria is lacking. By using 3-color flow cytometry, we analyzed 117 cases (bone marrow, 71; blood, 31; lymph nodes, 15) for coexpression of aberrant markers with CD19. Marker expression was considered positive when present on at least 20% of CD19+ cells. Of 117 cases, 40 (34.2%) showed expression of 1 or more aberrant markers. Expression of 4 aberrant markers was seen in 1 case, 3 in 4 cases, 2 in 15 cases, and 1 in 20 cases. Kaplan-Meier survival curves and the log-rank test revealed that the group with aberrant markers showed significantly shortened overall survival compared with the group without aberrant markers (P < .001). There is considerable phenotypic heterogeneity in CLL/SLL, and expression of aberrant markers indicates aggressiveness.     

Chronic lymphocytic leukaemia and its relationship to other lymphoproliferative disorders.

Chronic lymphocytic leukaemia is a disorder with variable clinical presentation, but with constant and easily recognizable morphological features. The majority of cases are of B-cell lineage, the cells being characterized by IgM and IgD surface markers. In occasional cases monoclonal gammopathies with idiotypes identical to those of the SIg are produced. Some cases of CLL may be confused with Waldenstr?m's macroglobulinaemia. The clinical and morphological features of certain other lymphoproliferative disorders have been summarized. Finally, a progression of B-cell differentiation along an immunoexpressive spectrum has been described and the relative position of CLL defined. A correlation of cell morphology and function is possible in most cases. The possibility that CLL may terminate in an acute blastic crisis or histiocytic lymphoma is raised. It is emphasized that LPD include a wide range of diseases, some being non-malignant, others of questionable malignancy, and still others being frankly malignant. Clinical, morphological and immunological data are required for diagnosis in some cases.     

Chronic lymphocytic leukemia/small lymphocytic lymphoma involving the aortic valve

Chronic lymphocytic leukemia/small lymphocytic lymphoma is a neoplasm composed of monomorphic small B lymphocytes in the peripheral blood, bone marrow, spleen, and lymph nodes, forming proliferation centers in tissue infiltrates (Muller-Hermelink HK, Montserrat E, Catovsky D, et al. Chronic lymphocytic leukaemia/small lymphocytic lymphoma, in Swerdlow SH (ed). WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues. Lyon, France, International Agency for Research on Cancer, 2008, pp. 180-182). We report a case of a 77-year-old man with a medical history of chronic lymphocytic leukemia who presented with worsening chest pain over 8 weeks. Imaging studies revealed severe aortic stenosis and moderate mitral regurgitation. He subsequently underwent minimally invasive aortic valve replacement and mitral repair at our institution. Grossly, the specimen consisted of a trileaflet valve with multiple yellow-white focally hemorrhagic and calcified nodules over its surface. Histologically, a lymphocytic infiltrate composed of monotonous small cells with scant cytoplasm was seen as well as calcification and fibrosis. Immunohistochemical stains were positive for CD20, PAX5, CD5, and CD23. To our knowledge, this is the first reported case of an immunohistochemically documented chronic lymphocytic leukemia/small lymphocytic lymphoma to involve a cardiac valve.     

Prostatic aspirates. A cytomorphologic analysis with emphasis on well-differentiated carcinoma

In this retrospective evaluation of 72 cases of fine needle aspiration biopsy of the prostate, 25 aspirates from well-differentiated carcinoma were compared with 27 aspirates from benign prostatic enlargement and 20 aspirates from moderately to poorly differentiated carcinoma. Each case was examined by a single observer (V.K.) for multiple parameters including cellularity, dyshesion, nuclear membrane irregularity, anisonucleosis, macronucleoli (major criteria of malignancy), cell and nuclear enlargement, and altered nuclear/cytoplasmic ratio. Cellularity was the most significant indicator, but all major and minor criteria of malignancy were consistently important for distinguishing well-differentiated carcinoma from benign lesions. Systematic use of these meaningful standards enhances diagnostic sensitivity.     

B-cell chronic lymphocytic leukemia/small lymphocytic lymphoma involving bone marrow with an interfollicular pattern

B-cell chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) may involve the bone marrow in nodular, interstitial, diffuse, or mixed patterns. However, B-cell CLL/SLL associated with large reactive germinal centers (the so-called interfollicular pattern) involving the bone marrow is not reported. We describe 2 examples of B-cell CLL/SLL that subtotally replaced the bone marrow with an interfollicular pattern. In both cases, the neoplasms were composed of small round lymphoid cells; proliferation centers also were present. The neoplasms surrounded large reactive germinal centers that were devoid of peripheral mantle zones. The germinal centers were paratrabecular and nonparatrabecular in case 1 and nonparatrabecular in case 2. Flow cytometry immunophenotypic studies done on bone marrow aspiration samples of both cases showed a uniform population of neoplastic cells positive for pan-B-cell antigens and the CD5 and CD23 antigens. Immunohistochemical studies done on bone marrow biopsy sections supported the flow cytometry results and demonstrated that the germinal centers were negative for BCL-2. B-cell CLL/SLL may rarely involve the bone marrow with an interfollicular pattern. Knowledge of this pattern will prevent confusion with follicle center lymphoma and large cell transformation, both of which initially were considered in the differential diagnosis of these cases.     

Concurrent classical Hodgkin lymphoma and plasmablastic lymphoma in a patient with chronic lymphocytic leukemia/small lymphocytic lymphoma treated with fludarabine: a dimorphic presentation of iatrogenic immunodeficiency-associated lymphoproliferative disorder with evidence suggestive of multiclonal transformability of B cells by Epstein-Barr virus

A small fraction of patients with chronic lymphocytic leukemia/small lymphocytic lymphoma develop Epstein-Barr virus–positive B-cell lymphoproliferative disorders. These Epstein-Barr virus–B-cell lymphoproliferative disorders are thought to be related to immune suppression induced by fludarabine/other chemotherapeutic regimens. As in other immunodeficiency-associated lymphoproliferative disorders, these disorders demonstrate a heterogeneous histological spectrum that ranges from polymorphic to monomorphic to classical Hodgkin lymphoma–like lesions. We report a case of concurrent classical Hodgkin lymphoma and plasmablastic lymphoma in a patient with chronic lymphocytic leukemia/small lymphocytic lymphoma treated with fludarabine. Both classical Hodgkin lymphoma and plasmablastic lymphoma were positive for Epstein-Barr virus-encoded RNA, whereas classical Hodgkin lymphoma was also positive for Epstein-Barr virus- latent membrane protein 1, suggesting a different viral latency. Immunoglobulin gene rearrangement studies demonstrated distinct clones in the plasmablastic lymphoma and chronic lymphocytic leukemia/small lymphocytic lymphoma. These findings suggest biclonal secondary lymphomas associated with iatrogenic immunodeficiency. Epstein-Barr virus–B-cell lymphoproliferative disorders in the setting of chronic lymphocytic leukemia/small lymphocytic lymphoma, in particular those arising after chemotherapy, should be separated from true Richter's transformation, and be categorized as (iatrogenic) immunodeficiency-associated lymphoproliferative disorder.     

No evidence of HTLV-I proviral integration in lymphoproliferative disorders associated with cutaneous T-cell lymphoma.

Several recent studies have reported detection of HTLV-I genetic sequences in patients with cutaneous T-cell lymphoma (CTCL) including mycosis fungoides and Sezary syndrome. The purpose of this study was to determine whether HTLV-I was detectable in lesional tissues of patients suffering from diseases known to be associated with CTCL. Thirty-five cases were obtained from diverse geographical locations including Ohio, California, Switzerland, and Japan. Six of them had concurrent CTCL. Cases were analyzed using a combination of genomic polymerase chain reaction (PCR)/ Southern blot, dot blot, and Southern blot analyses. All assays were specific for HTLV-I provirus. Sensitivity ranged from approximately 10(-6) for PCR-based studies to 10(-2) for unamplified genomic blotting. Lesional DNA from patients with lymphomatoid papulosis (fourteen cases), Hodgkin's disease (twelve cases), and CD30+ large-cell lymphoma (nine cases) was tested for the HTLV-I proviral pX region using a genomic PCR assay followed by confirmatory Southern blot analysis with a nested oligonucleotide pX probe. All cases were uniformly negative. All of the Hodgkin's disease cases, eight of the large-cell lymphoma cases, and six of the lymphomatoid papulosis cases were then subjected to dot blot analysis of genomic DNA using a full-length HTLV-I proviral DNA probe that spans all regions of the HTLV-I genome. Again, all cases were negative. Finally, eleven of the Hodgkin's disease cases were also subjected to Southern blot analysis of EcoRI-digested genomic DNA using the same full-length HTLV-I probe. Once again, all cases were negative. These findings indicated that, despite utilization of a variety of sensitive and specific molecular biological methods, HTLV-I genetic sequences were not detectable in patients with CTCL-associated lymphoproliferative disorders. These results strongly suggest that the HTLV-I retrovirus is not involved in the pathogenesis of these diseases.