Primary cutaneous follicular lymphoma: an assessment of clinical, histopathologic, immunophenotypic, and molecular features.

PURPOSE: Unlike nodal follicular lymphoma (NFL), Primary cutaneous follicular lymphomas (PCFLs) rarely express Bcl-2 protein or t(14;18)(q32;q21) (Bcl-2/IgH). The aim of this study was to further characterize PCFL in a large series from North America. PATIENTS AND METHODS: Clinical data and archival formalin-fixed, paraffin-embedded tissue were obtained from 32 patients. PCFL was defined as follicular lymphoma limited to the skin at the time of diagnosis and within the first 6 months after diagnosis. Specimens were analyzed for the expression of CD3, CD10, CD20, Bcl-2, and Bcl-6 proteins by immunohistochemistry as well as for the presence of t(14;18)(q32;q21) by polymerase chain reaction. RESULTS: The male-to-female ratio was 1.5:1, with a median age of 60 years. Twenty-four patients had lesions on the head and neck, five had lesions on the trunk, and three had lesions on both head and trunk. Follow-up data were available in all cases, with a mean length of 35.8 months. The majority of the patients were treated with radiation therapy. All patients were alive at last follow-up except one. Recurrence was noted in seven patients (22%), after a mean disease-free survival time of 17.7 months. CD10 and Bcl-6 expression were seen in 29 (91%) of 32 and 31 (97%) of 32 cases, respectively. Bcl-2 expression was noted in 13 (41%) of 32 cases. PCR results for t(14;18)(q32;q21) were positive in 11 (34%) of 32 patients and showed correlation with Bcl-2 protein expression. The sequencing of the t(14;18)(q32;q21) amplicons confirmed unique breakpoints in each of the seven tested cases. Comparison between the Bcl-2 and/or t(14;18)(q32;q21)-positive and t(14;18)(q32;q21)-negative cases revealed no significant difference in age, site, clinical course, or outcome. CONCLUSION: We demonstrated Bcl-2 protein expression and t(14;18)(q32;q21) in a significant minority of cases, suggesting a relationship with NFL. It remains to be seen whether, on longer follow-up, there is any clinical difference in cases with and without t(14;18)(q32;q21).

The pathology of the chronic lymphoid leukaemias.

The chronic lymphoid leukaemias, though they all possess relatively mature lymphoid phenotypes, are a diverse group of diseases at the clinical, morphological, immunophenotypical, and biological levels. Generally accepted entities within this category include B-cell chronic lymphocytic leukaemia of classical and mixed-cell types, B-cell and T-cell prolymphocytic leukaemia, hairy-cell leukaemia and hairy-cell variant, splenic lymphoma with circulating villous lymphocytes, large granular lymphocytic leukaemia, adult T-cell leukaemia/lymphoma syndrome, and leukaemic phases of malignant lymphomas of both B-cell and T-cell types. Recent advances have helped to differentiate these diseases, allowing the development of more specific therapy and more accurate prognostication. In this article, we review the pathological aspects of these diseases.

Pneumocystis carinii choroiditis in patients with AIDS: clinical features, response to therapy, and outcome.

To further characterize the clinical features, response to therapy, and outcome of Pneumocystis carinii choroiditis in patients with AIDS, we retrospectively reviewed the course of choroiditis for eight patients identified from two institutions through April 1991. Seven patients had prior Pneumocystis carinii pneumonia and had received aerosolized pentamidine prophylaxis for a median of 10 months; one patient had no prior history of pneumonia or prophylaxis. The median CD4+ lymphocyte count for six patients was 11 cells/mm3. Choroiditis was a preterminal diagnosis for three patients--two with associated disseminated pneumocystosis. Ocular manifestations improved or resolved with therapy for five of the six treated patients. All five subsequently received prophylaxis with dapsone (n = 2), dapsone/trimethoprim (n = 2), or aerosolized pentamidine (n = 1). Choroiditis recurred at 15 months in the one patient receiving aerosolized pentamidine. The median survival from time of diagnosis was 44 weeks. A literature review including an additional 40 cases support the conclusions that (a) Pneumocystis choroiditis is a rare complication of advanced HIV disease, occurring often in the context of systemic pneumocystosis; (b) ocular signs and symptoms may improve or resolve with specific antipneumocystis therapy; and (c) relapse may occur, particularly in those not receiving systemic prophylaxis.

Malignant ileal carcinoid with metastasis to adenocarcinoma of the ovary.

Metastasis of one tumor to another is an intriguing and rare phenomenon. Lung and breast malignancies are common donor tumors, while renal cell carcinoma and meningioma serve as frequent recipients. We report a case of malignant carcinoid of the ileum with metastasis to adenocarcinoma of the ovary. Histologic examination of the ovary showed a clear dimorphic pattern consisting of uniform polygonal cells arranged in an insular pattern and highly pleomorphic epithelioid cells forming small glands or solid nests. Immunocytochemical studies firmly established the distinct identity of the two tumors.

Anti-CD10 immunoperoxidase staining of paraffin-embedded acute leukemias: comparison with flow cytometric immunophenotyping.

CD10 is common in B-precursor acute lymphoblastic leukemia (ALL) but is rare in acute myeloid leukemia (AML). However, until recently, analysis for CD10 has generally required fresh or frozen tissue. 56C6 is a monoclonal antibody that is now commercially available for the detection of CD10 in routinely processed paraffin-embedded tissue. Immunoperoxidase stains for CD10 on paraffin-embedded bone marrow core biopsy specimens (B5-fixed, decalcified) and marrow aspirate clots (formalin-fixed) were compared with flow cytometric immunophenotyping for CD10 on fresh cell suspensions in 20 cases of AML and in 30 cases of ALL. CD10 detection by immunohistochemistry agreed with CD10 by flow cytometry in 98% (49 of 50) of acute leukemias. The results matched in 100% (20 of 20) of AML. Five percent (1 of 20) of AMLs expressed CD10. Two of the AMLs with monocytoid differentiation were interpreted as negative for CD10 by flow cytometry, although these had nonspecific dim immunofluorescence for multiple markers, including CD10, and these cases were negative by immunohistochemistry. CD10 detection by immunohistochemistry agreed with CD10 by flow cytometry in 97% (29 of 30) of ALL. Eighty-four percent (21 of 25) of B-precursor ALL and 40% (2/5) of T-lineage ALL expressed CD10 by immunohistochemistry. In 1 case of B-precursor ALL, CD10 was dimly positive in 24% of the blasts by flow cytometry but negative by immunohistochemistry. We conclude that immunohistochemical staining of paraffin-embedded tissue, either B5- or formalin-fixed, is an effective method for the detection of CD10 in acute leukemia. This technique is useful in distinguishing AML from ALL.

Adhesion molecule expression in CD5-negative/CD10-negative chronic B-cell leukemias: comparison with non-Hodgkin's lymphomas and CD5-positive B-cell chronic lymphocytic leukemia.

The classification of CD5-negative/CD10-negative chronic B-cell leukemias (CD5-/CD10- CBL) can be problematic. Most of these cases may represent leukemic non-Hodgkin's lymphoma (NHL) other than B-cell chronic lymphocytic leukemia (BCLL); nonetheless, some investigators still advocate the term "CD5-negative BCLL." Because adhesion molecule (AdMol) expression patterns reflect the biology of lymphoid neoplasms, we studied a series of 106 B-cell lymphoproliferative disorders, including CD5+ BCLL (n = 56), NHL other than BCLL (n = 35), and CD5-/CD10- CBL (excluding hairy cell leukemia and prolymphocytic leukemia) with no prior history of NHL (n = 15) for expression of components of the very late antigen-4 complex (alpha4/beta1 integrin (CD49d/CD29)), components of the mucosal addressin-cell adhesion molecule receptor (alpha4(CD49d)/beta7 integrin), and L-selectin (CD62L). CD62L expression was significantly greater in CD5+ BCLL than in NHL (P < .001). Conversely, CD29, CD49d, and beta7-integrin expression were significantly greater in NHL than in CD5+ BCLL (P < .001 for each marker). These differences persisted when only blood and bone marrow samples were analyzed, with the exception of differences in CD62L expression, which approached, but did not reach, statistical significance (P = .08). The group of CD5-/CD10- CBL displayed an AdMol profile similar to NHL and was significantly different than CD5+ BCLL in expression of beta7 integrin, CD29, CD49d, and CD62L (P range < .001-.011). In summary, CD5-/CD10- CBL display an AdMol profile resembling NHL and significantly different from CD5+ BCLL, supporting the growing notion that "CD5-negative BCLL" generally represents leukemic NHL rather than a variant of true CD5+ BCLL.

Cytomegalovirus-infected cells in routinely prepared peripheral blood films of immunosuppressed patients.

We describe 4 patients identified over 5 years with large atypical cells on the feathered edge of routinely prepared peripheral blood films. Films were reviewed either as part of a blood film consultation or a bone marrow examination. The cells were 50 to 60 microns in diameter, with granular eosinophilic cytoplasmic inclusions and eccentric enlarged nuclei. Additional studies including buffy coat preparations and immunohistochemistry revealed that these were circulating cytomegalovirus (CMV)-infected cells, most likely of endothelial origin. All patients were immunocompromised (3 had HIV infection, and 1 was an organ transplant recipient) and had clinical evidence of CMV infection. The unique appearance of these cells at Wright-Giemsa staining, and their possible misidentification as malignant cells or other cells, highlights the need for pathologists to be aware of their morphologic features and possible clinical implication.

DNA flow cytometric analysis of hemangiopericytoma.

The biologic behavior of hemangiopericytoma is difficult to predict using clinical or histologic criteria. The authors studied 22 hemangiopericytomas (including "angioblastic meningiomas") from 16 patients. Included in the study were six recurrent tumors and one metastatic tumor. DNA flow cytometric analysis was performed on 21 tumors for which paraffin-embedded material was available. All of the tumors were DNA diploid. However, among patients with adequate follow-up information, all tumors that exhibited aggressive behavior (local recurrence, metastasis, death due to invasive disease) had S-phase fractions of greater than 9% and proliferative indices (S-phase plus G2M phase) of greater than 11%. There was also a trend toward aggressive behavior in tumors with necrotic foci. Tumors arising in the central nervous system behaved more aggressively than primary tumors at other sites. This study showed a trend toward more aggressive behavior in hemangiopericytomas with higher proliferative indices. DNA ploidy, however, was not a useful indicator of biologic behavior in these tumors.

Enhanced detection of malignant lymphoma in cerebrospinal fluid by multiparameter flow cytometry.

Immunophenotyping by flow cytometry has not been widely applied to cerebrospinal fluid (CSF) analysis. We attempted to optimize flow cytometric detection of malignant lymphoma in CSF samples by the routine use of 3- and 4-color flow cytometry, with specific selection of lymphoid cells by fluorescence vs 90 degrees light scatter gating. Thirty-six consecutive CSF samples were immunophenotyped by flow cytometry, and the results were compared with those of standard microscopic examination. Lymphoid events were adequate for analysis in 27 of the 36 samples. Each of the 9 unsuccessful samples was more than 24 hours old at analysis or contained fewer than 1 x 10(4) total cells (< or =1 cell/microL). Lymphoma was detected in 10 of the remaining 27 cases. Six lymphomas were detected by morphology and flow cytometry, 1 only by morphologic examination, and 3 only by flow cytometry. Therefore, the combination of flow cytometry and morphologic examination enhanced the detection by 43% over morphologic examination alone. Flow cytometry permitted the detection of lymphoid clones totaling less than 1% of total cells. Multicolor flow cytometry is a rapid and sensitive technique that enhances detection of lymphoma in paucicellular CSF samples. Given the great sensitivity of flow cytometry, future studies will be necessary to assess the significance of detecting small lymphoid clones in this setting.

Isolated 13q14 abnormalities and normal karyotypes are associated with typical lymphocyte morphology in B-cell chronic lymphocytic leukemia.

Peripheral blood lymphocyte morphology and karyotype were correlated across the spectrum of cytogenetic abnormalities in 78 previously karyotyped cases of B-cell chronic lymphocytic leukemia (CLL). Cases were classified according to French-American-British morphologic criteria as typical CLL or CLL, mixed-cell type; the latter category was divided into CLL with a mixture of small and large cells and CLL with increased prolymphocytes (CLL/PL). Other leukemic lymphoproliferative disorders were excluded from this analysis. CLL cases with normal karyotypes were more likely to demonstrate typical morphology than those with clonal abnormalities (P = .042). In addition, all six cases containing isolated 13q14 abnormalities had typical morphology, compared with six of 16 other isolated abnormalities (P = .009), including one of seven cases of isolated trisomy 12. In contrast with the cases of isolated 13q14 changes, only seven of 17 cases with 13q14 as part of complex abnormalities had typical morphology (P = .012). Trisomy 12 was associated with mixed-cell morphology, particularly CLL/PL, consistent with previous reports. We conclude that isolated 13q14 abnormalities and normal karyotype are associated with typical CLL morphology, while other clonal abnormalities, including trisomy 12, are associated with mixed-cell morphology. These results further support the concept of distinct CLL subgroups based on karyotype. Furthermore, the association of trisomy 12 and complex abnormalities with mixed-cell morphology may have implications for clonal evolution in CLL.

Follicular large cell lymphoma with immunoblastic features in a child with Wiskott-Aldrich syndrome: an unusual immunodeficiency-related neoplasm not associated with Epstein-Barr virus.

Patients with Wiskott-Aldrich syndrome, a severe inherited immunodeficiency disorder, have a markedly increased risk of developing non-Hodgkin's lymphoma compared with the general population. These are uniformly diffuse aggressive B-cell neoplasms that resemble those seen in AIDS and the posttransplantation setting and also may be associated with Epstein-Barr virus. We report what to our knowledge is the first case of follicular lymphoma in a 14-year-old child with Wiskott-Aldrich syndrome. The neoplasm was composed predominantly of large cells with immunoblastic features, and it possessed light chain-restricted surface immunoglobulin, clonal immunoglobulin gene rearrangements, and a t(14;18). The tumor lacked Epstein-Barr virus sequences by in situ hybridization and Southern blot terminal repeat analysis. Interestingly, however, the tumor contained c-myc gene rearrangement.

CD5- small B-cell leukemias are rarely classifiable as chronic lymphocytic leukemia.

Expression of the CD5 antigen by neoplastic cells often is considered a diagnostic criterion for B-cell chronic lymphocytic leukemia (B-CLL). However, published series frequently include a number of CD5- cases. We studied the spectrum of CD5- B-cell lymphoproliferative disorders presenting with leukemia involvement and reassessed the prevalence of CD5- B-CLL. We immunophenotyped 192 cases of clonal, small lymphocytic, B-cell disorders involving peripheral blood or bone marrow. Of these, 41 CD5- cases were further analyzed, correlating the immunophenotypic findings with pathologic material and clinical data. Only 3 CD5- cases were classified as CD5- B-CLL. These 3 cases had features unusual for B-CLL, including bright surface immunoglobulin expression, bright CD20 expression, and absence of CD23 expression (2 cases) or Richter syndrome (1 case). The remainder of the CD5- cases consisted of hairy cell leukemia, hairy cell variant, prolymphocytic leukemia, follicular center cell lymphoma, lymphoplasmacytic lymphoma, splenic marginal zone lymphoma (SMZL), small lymphocytic lymphoma with marrow fibrosis, and lymphoma, not further classified. Eight cases remained unclassified, but some displayed features of SMZL. CD5- lymphoproliferative disorders of peripheral blood or bone marrow are unlikely to be CLL and often are classified more appropriately as non-Hodgkin lymphoma in the leukemia phase.

Waldenström macroglobulinemia caused by extranodal marginal zone B-cell lymphoma: a report of six cases.

Waldenström macroglobulinemia (WM) and its associated hyperviscosity syndrome (HVS) are generally caused by lymphoplasmacytoid lymphoma or other small B-cell lymphoproliferative disorders. WM associated with extranodal marginal zone B-cell-mucosa-associated lymphoid tissue lymphoma (EMZL/MALT-type) has not been emphasized. We describe 4 men and 2 women (age, 40-79 years) with clinical and laboratory manifestations of WM and EMZL/MALT-type involving one or more sites: lung, pericardium/pleura, ocular adnexa, nasopharynx, minor salivary gland, glossopharyngeal fold, skin, and stomach. The following immunophenotypic patterns were observed: CD20+, 6; CD43+, 3; kappa light chain restriction, 5; and lambda light chain restriction, 1. All were negative for CD5, CD10, and cyclin D1 expression. A clonal paraproteinemia was present in each (IgM kappa, 4; IgM lambda, 1; biclonal IgM kappa/IgA kappa, 1). All 4 patients tested had elevated plasma viscosity; clinical HVS occurred in 3, and 2 required emergency plasmapheresis. These findings suggest that EMZL/MALT-type can cause WM and that the laboratory evaluation of EMZL/MALT-type should include serum protein electrophoresis/immunofixation, and plasma viscosity measurements and urine immunofixation in select cases. EMZL/MALT-type should be considered in the differential diagnosis in patients with clinicopathologic features of WM.

The clinical significance of CD10 antigen expression in diffuse large B-cell lymphoma.

The clinical significance and prognostic value of CD10 in de novo diffuse large B-cell lymphoma (DLBCL) is largely unknown. We retrospectively studied 19 men and 9 women based on the following criteria: (1) DLBCL with no evidence of concomitant or antecedent follicular lymphoma; (2) available flow cytometric immunophenotyping data, including CD10 status; (3) older than 15 years; (4) specific exclusion of high-grade, Burkitt-like lymphoma; and (5) exclusion of primary cutaneous DLBCL. When available, clinical data at diagnosis, including components of the international prognostic index, were reviewed. Eleven cases were CD10+, and 17 were CD10-. There was no significant difference between the CD10+ and CD10- groups in age, sex, stage, performance status, extranodal involvement, or serum lactate dehydrogenase levels at diagnosis. However, in the 26 cases for which follow-up data were available, the CD10+ group displayed a shorter overall survival than the CD10- group (8 vs 30 months). Although the clinical findings at diagnosis are similar in CD10+ and CD10- DLBCL, CD10 expression is associated with shortened overall survival. Therefore, our data suggest CD10 expression may have prognostic importance in adults with de novo DLBCL.

Karyotype correlates with peripheral blood morphology and immunophenotype in chronic lymphocytic leukemia.

Chronic lymphocytic leukemia (CLL) is recognized as a distinct entity. However, morphologic and immunophenotypic heterogeneity exist. Twenty-six patients with CLL were studied to investigate whether an association exists among peripheral blood karyotype, morphology and immunophenotype. Clonal cytogenetic abnormalities were detected in 14 patients (53%), using conventional karyotyping techniques in addition to fluorescence in situ hybridization (FISH) for chromosome 12. By FAB guidelines, 7 of the 8 patients (88%) with trisomy 12 had mixed cell morphology compared to only 3 of 18 (17%) without trisomy 12 (P = .004). One patient (12%) with trisomy 12 had lymphocyte morphology typical for CLL. Six of the eight (75%) with trisomy 12 had atypical immunophenotype including one or more of the following: strong CD20 expression, strong surface light chain expression, or absence of CD23 expression. Only 2 of the 18 patients (11%) without trisomy 12 had atypical immunophenotype (P = .005). None of the three patients with clonal structural abnormalities of chromosome 13q14 had mixed cell morphology or atypical immunophenotype. One of the 12 patients (8%) without clonal cytogenetic abnormalities had mixed cell morphology and one had atypical immunophenotype. This study suggests that a correlation exists among karyotype, morphology, and immunophenotype in CLL, and that CLL subgroups can be identified based on laboratory parameters. Although normal karyotypes or clonal structural abnormalities of 13q14 are associated with morphology and immunophenotype considered typical for CLL, trisomy 12 is associated with mixed cell morphology and atypical immunophenotype. These findings may have implications for evaluating variation in both disease course and response to emerging therapies.

Precursor B-lymphoblastic transformation of grade I follicle center lymphoma.

Part of the natural history of follicle center lymphoma (FCL) is transformation to a more aggressive neoplasm, almost always a diffuse large B-cell lymphoma. We describe a rare example of a precursor B-lymphoblastic transformation of grade I FCL occurring in a 45-year-old woman 12 years after initial presentation and 3 years after successful treatment for a diffuse large cell transformation. The lymphoblastic lymphoma shared the same immunoglobulin heavy chain gene rearrangement as the FCL as assessed by polymerase chain reaction amplification and direct sequencing, as well as identical kappa light chain gene rearrangements by Southern blot analysis. The immunoglobulin heavy chain variable gene sequences of both tumors showed numerous identical base substitutions compared with germline sequences and 3 additional mutations in the lymphoblastic lymphoma not present in the low-grade FCL. These results indicate origin of the lymphoblastic process from the mature follicle center B-cell clone, rather than divergent origin of the 2 tumors from a common immature B-cell precursor.

Modified APC-resistance test: variable ratios with respect to source of factor V-deficient plasma.

A single point mutation of the factor V (FV) gene, leading to the substitution Arg506Gln in the FV molecule (FV-Leiden) and hence resistance to its breakdown by activated protein C (APC), is the most prevalent risk factor for venous thrombosis in the Caucasians. A ratio determined by activated partial thromboplastin time (APTT) of test plasma in the presence or absence of exogenous APC (the APC ratio), is the method widely used to screen individuals with this risk factor for thrombosis. Because of functional defects of vitamin K-dependent clotting factors in patients on oral anticoagulant therapy, this method cannot be applied to those patients without modification. One modification is to mix test plasma (1:5 or 1:10) with FV-deficient plasma so that 80-90% of functioning vitamin K-dependent factors are supplied by the FV-deficient plasma. Even with 10-20% of FV in the mixture, APC-resistance still can be demonstrated. In this report, we present our results of the modified APC-sensitivity assay using FV-deficient plasma from different commercial sources. APC ratios determined by the original method in which test plasma is not mixed with FV-deficient plasma can be significantly different from those determined by the modified method in which test plasma is diluted 1:5 with FV-deficient plasma. This difference between methods was observed not only in normal individuals, but also in FV-Leiden positive individuals, and in patients on warfarin therapy. Further, APC ratios varied significantly depending on the commercial source of the FV-deficient plasma. The modified method is apparently suitable to identify APC-resistance in patients on warfarin therapy, as well as in individuals not receiving anticoagulant treatment. However, one must be aware that APC-resistance ratios obtained with the modified method are likely to be different from those established with the original method, and the source of FV-deficient plasma can be a factor influencing the ratios in the former cases.