CLL and diffuse histiocytic lymphoma in one patient: clonal proliferation of two different B cells

Secondary follicular lymphoma of the bone, transformed into large cell lymphoma, in a patient with chronic lymphocytic leukaemia: an uncommon manifestation of Richter's syndrome

Patients with chronic lymphocytic leukemia (CLL) are at a significantly increased risk of developing a second malignant neoplasm in the course of their disease. The occurrence of large cell lymphoma [Richter's syndrome (RS)] has been described in approximately 3-5% of CLL patients. Other types of secondary lymphoid malignancies are extremely rare. Here we describe a patient, heavily pretreated, with long history of CLL who developed a secondary follicular lymphoma, transformed into a diffuse large cell lymphoma (LCL), with isolated manifestation in the bone, a very rare manifestation of RS. CLL and LCL cells were of distinct clonal origin, as documented by DNA sequencing of the CDR3 regions. Twelve months after the completion of chemo- and local radiotherapy, the patient is still in remission.

Richter syndrome in B-cell chronic lymphocytic leukemia

Richter syndrome (RS) is well known as a secondary high-grade lymphoma, mostly diffuse large B-cell lymphoma (DLBCL) developed in patients with B-cell chronic lymphocytic leukemia (B-CLL). In this review, we describe clinicopathological, histological, immunophenotypical and genetic findings of RS. The patients with RS, regardless of transformation of pre-existing clone or de novo malignant clone, were resistant to conventional combined chemotherapy and died within months of diagnosis. Molecular techniques can provide convincing results for the clonal relationship of RS to pre-existing B-CLL. When RS carries a same rearrangement band or a same sequence as B-CLL by Southern blotting or nucleotide sequence analyses of immunoglobulin heavy and/or light chain genes, it is suggested to that RS transforms from original B-CLL. These analyses have showed that approximately two-thirds of RS cases evolved from a B-CLL clone. How and where does the B-CLL clone evolve to RS? The genetic alteration of transforming B-CLL clone into RS has been addressed. Abnormalities of chromosomes 11 and 14 were most frequently involved in RS, but non-specific. In addition, RS does not include chromosomal translocation between Ig locus and oncogenes or rearrangements of bcl-6 gene, both of which were found in some de novo DLBCL. Several candidates, such as mutation of p53 gene and abnormalities of cyclin dependent kinase inhibitor, have been proposed to play an important role in the transformation of a part of B-CLL. However, there is still uncertainty as to how B-CLL progresses or develops into RS.

Hodgkin's disease developing after spontaneous remission of chronic lymphocytic leukemia

We present a 71-year-old patient with chronic lymphocytic leukemia diagnosed 27 years ago. Initially, the disease was staged as Rai II and the patient suffered from secondary immunoglobulin deficiency. Nevertheless, no treatment was necessary at that time. Because of disease progression a single course of chemotherapy was given in 1984. During the following year there was a constant decline of the WBC, accompanied by normalization of the immunoglobulins; both have remained stable ever since that time. However, there was still residual bone marrow infiltration, indicating persisting CLL. In 1993 cervical lymphadenopathy occurred with acute onset. A diagnostic lymphadenectomy revealed Hodgkin's disease of the nodular-sclerosing subtype. The patient was staged as II-III according to the Ann Arbor Classification and underwent radiation therapy. Cytogenetic examination of the bone marrow revealed a normal karyotype with an inversion of chromosome 9. This case demonstrates the rate coincidence of two lymphoproliferative disorders in the same patient. The clinical course and the immunologic findings of this patient are presented, together with a review of the literature.

Transformation of chronic lymphocytic leukemia to lymphoma of true histiocytic type

BACKGROUND

Chronic lymphocytic leukemia (CLL) may evolve into large cell lymphoma (Richter's syndrome), prolymphocytic leukemia, acute lymphoblastic leukemia, and myeloma.

METHODS

A patient with CLL that transformed into a lymphoma of true histiocytic type is described, and the literature on the association of these two disorders is reviewed.

RESULTS

Lymphomas of true histiocytic type developing as an aggressive terminal phase of CLL previously have been reported in nine patients. Fever and rapidly increasing lymphadenopathy and splenomegaly were the most common signs and symptoms. As with de novo lymphoma of true histiocytic type, extranodal involvement of the soft tissue, gastrointestinal tract, kidneys, bone marrow, liver, and lungs was documented among the 10 patients with lymphoma of true histiocytic type transformed from CLL. The median interval between diagnosis of CLL and the evolution to lymphoma of true histiocytic type was 25.5 months. Patients with lymphomas of true histiocytic type after CLL were treated with fludarabine and various other combination chemotherapy regimens with only short-lived responses. The median time to death after transformation was only 33 days (range, 10 days to 5 months).

CONCLUSION

Lymphomas of true histiocytic type appear to represent an additional, though uncommon, form of transformation in CLL. Although their presentation is reminiscent of other intermediate to high grade lymphomas, they can be distinguished based on their morphologic and immunophenotypic features. In the patients described in this study to date, transformation of CLL to lymphomas of true histiocytic type is a poor prognostic sign, with survival generally of only days to weeks.

Origin of high-grade lymphomas in Richter syndrome

Patients with B cell chronic lymphocytic leukemia (CLL) occasionally develop high-grade B cell lymphomas that are associated with constitutional symptoms, rapidly progressive lymphadenopathy, and swift clinical deterioration. Now known as Richter syndrome, this symptom complex develops in approximately 5% of all patients with CLL. Structural and molecular analysis of the immunoglobulin (Ig) genes have allowed investigators to define the clonal relationship between the leukemia and lymphoma cells of a given patient. In most cases the aggressive lymphoma evolves from the original leukemia cell clone. However, in some cases the lymphoma apparently represents a second malignancy. Differentiation between these two types of lymphoma may have clinical significance. Further investigation is required to allow for identification of CLL patients who are at risk for developing Richter syndrome and to understand factors involved in its etiopathogenesis.

Clonal heavy chain isotype switching within the proliferation centers of a small lymphocytic lymphoma: implications regarding the origin of proliferation centers

We describe an unusual case of small lymphocytic lymphoma with multiple prominent pseudofollicular proliferation centers in which immunohistochemistry reveals that the small cells are surface IgM kappa positive and the large pseudofollicular cells are surface IgA kappa positive. We further show by genomic DNA analysis that the tumor tissue contains two JH rearrangements, one Cmu rearrangement, one C alpha rearrangement, and a single C kappa rearrangement, strongly suggesting that the large cells within the proliferation centers have arisen from the small cells via a clonal heavy chain immunoglobulin isotype switch. Isotype switching in human lymphoma and leukemia appears to be an uncommon event. However, there are reports that strongly support isotype switching in pre-B-cell leukemia, Richter's syndrome, lymphoid blast crisis of chronic myelogenous leukemia, and multiple myeloma. To our knowledge, there have been no previous reports demonstrating isotype switching within the proliferation centers of small lymphocytic lymphoma. We present evidence of in vivo intratumoral isotype switching within the proliferation centers of a small lymphocytic lymphoma documented at the level of immunohistochemistry and DNA rearrangement.

Evidence of clonal progression in a case of Richter syndrome

BACKGROUND

The debate continues as to whether Richter syndrome should be defined as non-Hodgkin lymphoma (NHL) because of a more malignant clone of neoplastic cells superimposed on preexisting chronic lymphocytic leukemia (CLL) or as the chance occurrence of two unrelated tumors. The cellular characteristics of the neoplastic clone involved in the CLL phase and the subsequent NHL were investigated in a patient in whom Richter syndrome developed.

METHODS

Cell analysis was performed with immunofluorescence, histologic analysis, DNA extraction, and Southern blot analysis.

RESULTS

The separated CLL and NHL B-cells from blood and bone marrow, as well as the neoplastic cells in autopsy specimens of the organs affected by NHL, particularly the brain, were found to express the same light chain of surface immunoglobulin (SIg). The change MD-->M in the SIg heavy-chain expression and the appearance of cytoplasmic IgMk suggested isotype switching simulating that observed on the final phases of primary B-cell differentiation. This hypothesis was confirmed by Southern blot analysis of DNA from blood cells in the CLL phase and in Richter transformation, which showed that the two cell populations had identical Ig gene rearrangement.

CONCLUSIONS

The NHL in the patient in this study represented a malignant progression of CLL, not a second lymphoid malignancy.

Heterogeneous immunoglobulin gene rearrangement in a B-chronic lymphocytic leukemia progressing into non-Hodgkin lymphoma (Richter syndrome)

BACKGROUND

The relationship between chronic lymphocytic leukemia (CLL) and supervening non-Hodgkin lymphoma is debated, as is whether a particular genomic pattern is related to the emergence of the terminal lymphoma. To investigate these features, the molecular organization of the immunoglobulin (Ig) gene region in a case during both the B-CLL and Richter transformation phase was studied.

METHODS

B-CLL and non-Hodgkin lymphoma cells were processed for Southern blot analysis of Ig heavy- and light-chain gene configuration.

RESULTS

Molecular studies of B-CLL cells revealed the presence of a single Ig heavy-chain rearrangement with both kappa and lambda light-chain rearranged genes, which was consistent with the occurrence of multiple mutational events during the development of the B-CLL clone. Molecular analysis of the lymphoma DNA showed new Ig heavy- and kappa light-chain rearrangements in addition to the original ones related to the CLL phase, indicating that the lymphoma tissue consisted of two genotypically distinct populations of cells.

CONCLUSIONS

On the basis of the overall molecular configuration, this heterogeneous pattern of Ig gene rearrangement was interpreted as an inherent genetic instability of the CLL clone, in which multiple mutational events allowed a selective pressure toward more aggressive subclones, resulting in the emergence of the terminal lymphoma.

Diffuse large cell lymphoma occurring in a patient with Waldenström's macroglobulinemia. Evidence for the two different clones in Richter's syndrome

The authors report a 60-year-old man with Richter's syndrome, or diffuse large cell lymphoma (DLCL) occurring in a patient with either chronic lymphocytic leukemia (CLL) or Waldenström's macroglobulinemia (WM). Surface marker analysis revealed that the WM showed mu kappa surface immunoglobulin (Ig) chains, and that the DLCL showed mu lambda Ig chains. Flow cytometric DNA analysis demonstrated DNA content differences between WM and DLCL, the former diploid and the latter aneuploid. The current study suggests that Richter's syndrome derives from two independent B-cell malignancies.

Late relapse with nodular lymphoma after treatment for diffuse non-Hodgkin's lymphoma

Histologic conversion from a low-grade non-Hodgkin's lymphoma (NHL) into a more aggressive histologic pattern is a common, well-documented event in NHL. The converse phenomenon, appearance of a low-grade, follicular NHL after treatment for diffuse, intermediate, or high-grade NHL, has only recently been recognized. The clinical, morphologic, and immunologic features of a patient in whom relapse with an indolent nodular lymphoma was noticed after combination chemotherapy for diffuse lymphoma are presented. Immunologic markers at presentation and relapse were similar. Other previously reported cases are reviewed. Implications for diagnosis and therapy as well as the pathogenesis of this unique form of conversion are discussed.

Genotypic analyses of Richter's syndrome

The authors report the immunogenotype of two cases of Richter's syndrome. The immunoglobulin gene rearrangement pattern obtained on Southern Blot analysis was found in both cases to be the same in leukemic blood cells and in the tissue involved by the lymphoma. The beta chain and gamma chain T-cell receptor gene rearrangement pattern exhibited a germ-line configuration in the peripheral blood cells and in the lymph node in Case 2, whereas in Case 1 the lymph node had a gene rearrangement in the beta chain, as well as in the gamma chain T-cell receptor, and the leukemic cells from bone marrow were found to be in a germ-line configuration for T-cell receptors (beta and gamma chains).

Discordant differentiation antigen pattern in a case of Richter's syndrome with monoclonal idiotype expression and immunoglobulin gene rearrangement

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The clonal origin of two cell populations in Richter's syndrome

A case of Richter's syndrome was studied by morphology, immunohistochemistry, flow cytometry, and immunoglobulin gene rearrangement. Flow cytometric study clearly demonstrated two monoclonal populations. The use of double staining with CD 5/CD 19 antibodies accompanied by two-color flow cytometric analysis clearly defined the chronic lymphocytic leukemia population and separated it from the lymphoma population. Immunoglobulin heavy-chain gene analysis of blood and lymph node specimens revealed nonidentical as well as identical nongermline bands in these two populations. However, light-chain gene analysis demonstrated that both populations shared a common clonal origin. This result underscores the unreliability of using heavy chain genotype alone to identify clonal origin. Since post-rearrangement deletion, point mutation, and heavy chain switching occur in heavy chain genes, but are seldom seen in light chain genes, it is important to analyze both heavy and light chain genes to conclusively determine clonal origin.

Single clonal origin of neoplastic B-cells with different immunoglobulin light chains in a patient with Richter's syndrome

A 71-year-old man was found to have chronic lymphocytic leukemia (CLL) and diffuse large cell lymphoma (DLC) simultaneously and was diagnosed as Richter's syndrome. The CLL had mu lambda surface immunoglobulin (sIg) whereas the DLC had mu kappa sIg. However, the immunoglobulin (Ig) gene rearrangement and surface marker analysis demonstrated that both CLL and DLC had identical rearrangement patterns of the Ig heavy chain (IgH) and identical surface markers CD5+, CD19+, and CD20+. These facts imply that in this case the two malignancies are of single clonal origin initially, and that different sIg of CLL and DLC do not, therefore, necessarily indicate the biclonality of these malignancies. The origin of DLC in Richter's syndrome remains controversial. This case suggests difficulty in concluding the biclonality of these malignancies. For a conclusion on clonality to be definitive, there is a need for cloning and nucleotide sequencing of rearranged Ig genes in more patients with Richter's syndrome.

Imprint cytology of non-Hodgkin's lymphomas based on a study of 212 immunologically characterized cases: correlation of touch imprints with tissue sections

The classification of non-Hodgkin's lymphomas (NHLs) has been traditionally based on analysis of histologic sections and has been supplemented more recently by immunologic marker studies. It was the purpose of the present study to illustrate, side-by-side, sections and Romanowsky-stained imprints from the same surgical specimen from practically all categories of immunophenotyped NHLs, including rare and atypical variants that were difficult to classify from the histologic sections alone. Our results indicate that imprint cytology may reveal nuclear and cytoplasmic details not discernible in even the best tissue sections and that it may be selectively helpful in contributing to the classification of NHLs. Our results also show that the relative value of imprint cytology in the classification of malignant lymphomas varies greatly among categories. Specifically, we have found that imprints assist in three ways: the recognition of plasmacytoid features in small cell lymphocytic lymphomas, the recognition of plasmacytoid immunoblastic lymphoma, and the differentiation between NHLs which may be difficult to distinguish histologically. These include (1) small lymphocytic lymphoma versus lymphocytic lymphoma of intermediate differentiation, (2) true histiocytic malignancies versus large cell malignant lymphomas with abundant cytoplasm and/or phagocytosis, (3) anaplastic myeloma versus plasmacytoid immunoblastic lymphoma, (4) large noncleaved versus plasmacytoid immunoblastic lymphoma, (5) lymphoblastic lymphoma versus diffuse small cleaved cell lymphoma, and (6) lymphoblastic lymphoma versus small noncleaved cell lymphoma. Lymph node imprints are easy to prepare and readily interpretable by those experienced in the study of abnormal blood and bone marrow films. Their value as an ancillary methodology aimed at optimal accuracy in the classification of NHLs should be recognized.

Centroblastic lymphoma of the thyroid supervening long-lasting chronic lymphocytic leukemia (B-CLL) demonstration of biclonality by immunohistochemical and gene rearrangement analysis

A 67-year-old woman suffering since 5 years from a so far nontreated B-CLL underwent hemithyroidectomy for a rapidly enlarging tumor. Histologically, the coincidence of a centroblastic lymphoma and thyroidal infiltration by the CLL was diagnosed. Immunohistology revealed typical immunoprofils for both, B-CLL and centroblastic lymphoma on the background of B cell differentiation antigens. The bitypical immunoglobulin light chain expression--lambda on the B-CLL cells and kappa on the centroblasts--suggested biclonality. This was confirmed by gene rearrangement analysis of peripheral leukemia cells and tumor tissue. Thus, the final diagnosis of a primary thyroidal lymphoma of the centroblastic type (stage IE) arising independently from a preexisting B-CLL was achieved. Consequently, the patient received local radiotherapy. In our opinion, the designation "Richter's Syndrome", readily applied in the literature, is inappropriate for this tumor constellation.

Relapsing large cell immunoblastic lymphoma complicating well-differentiated lymphocytic lymphoma: a report of two cases showing prolonged survival with therapy

Two patients presented with co-existing large cell immunoblastic and well-differentiated lymphocytic lymphomas. Prolonged remissions from the large cell lymphomas were achieved following intensive combination chemotherapy but both patients suffered relapses after many years. Previous reports have grouped such patients with those developing classical Richter's syndrome implying a uniformly poor prognosis. This report suggests that this is not the case. It was not possible with immunohistochemical stains to prove or disprove that these tumours had the same stem cell origins.

A reappraisal of Richter's syndrome. Development of two phenotypically distinctive cell lines in a case of chronic lymphocytic leukemia

Richter's syndrome, the development of a malignant lymphoma in a patient with preexisting chronic lymphocytic leukemia (CLL) is an infrequent but well-documented phenomenon generally thought to represent a monoclonal proliferation of B-lymphocytes arising from the CLL. A heterogeneous population of cells consisting of sheets of transformed lymphocytes in combination with clusters of bizarre, atypical histiocytes developed in a patient with a history of longstanding CLL. Immunocytochemistry using a panel of monoclonal and polyclonal antibodies by immunoperoxidase techniques identified the presence of both B-lymphocytic and monocytic-histiocytic cell lines of differentiation. A mechanism of multiple differentiation is proposed to account for the dual cell population observed in this patient. Review of the literature appears to indicate that this phenomenon often may be involved in cases diagnosed as Richter's syndrome. The demonstration of cellular heterogeneity in the current case underscores the need for establishing a more precise definition for the histologic characterization of the terminal malignancy in Richter's syndrome.

Sustained complete remission in Richter's syndrome

Richter's syndrome is the development of an aggressive diffuse lymphoma in chronic lymphatic leukemia (CLL) and is associated with a poor prognosis. A patient with CLL developed Richter's syndrome, which responded to intensive chemotherapy. Spontaneous regression of CLL in blood and marrow was observed at the onset of Richter's syndrome. The patient remained in complete remission from the lymphoma 4 years after the completion of treatment, and there was no evidence of CLL.

Richter's syndrome with two different B-cell clones

The diagnoses of chronic lymphocytic leukemia (CLL) in prolymphocytic transformation, and diffuse large cell lymphoma (DLC), were made simultaneously in a 71-year-old man. The DLC showed mu lambda surface immunoglobulin. The CLL in a lymph node and in the peripheral blood showed mu kappa. Immunoglobulin gene DNA analysis confirmed the presence of different rearrangements in the heavy and light chain genes of the CLL and DLC. Other cases reported of Richter's syndrome are discussed, and it is concluded that there may be two types of Richter's syndrome, those arising from transformation of a single clone, and those occurring from expansion of two morphologically and immunologically distinct clones, as, it is believed, is the case in this patient.

Phenotypic changes in large cell transformation of small cell lymphoid malignancies

Large cell transformation of two cases of chronic lymphocytic leukemia and two cases of small lymphocytic lymphoma were studied. Changes in surface immunoglobulins were observed in two cases. In one case, there was a change from IgM to IgG. In another case, the large cells bore kappa light chains whereas the small cells had lambda light chains. Surface antigens other than immunoglobulin might also differ. All three small cell malignancies tested, but none of the large cell tumors, expressed the antigen T1 (Leu 1). The antigens HLA-DR, Leu 14, B1, and BA1 were expressed by both the small and large cell malignancies with one exception. The staining intensity might, however, change on transformation. The common acute lymphocytic leukemia antigen was not detected on any of the tumors studied and the expression of BA2 was variable. Surface marker studies cannot confidently distinguish between large cell lymphomas resulting from clonal evolution and those arising de novo. More definitive studies such as analyzing the idiotypic determinants on and amino acid sequences of the heavy and light chains or analyses of immunoglobulin gene rearrangements are necessary to confirm or exclude the same clonal origin in such cases.

Prolonged survival in Richter syndrome with subsequent reemergence of CLL: a case report including serial cell-surface phenotypic analysis

The development of a large cell lymphoma in a patient with chronic lymphocytic leukemia (Richter syndrome) is associated with a poor prognosis. There is dispute regarding the clonal origin of the large cell component. We described a patient in whom prolonged remission of the large cell component was achieved with combination chemotherapy, followed by subsequent reemergence of the less aggressive CLL clone. Serial cell surface phenotypic data are presented suggesting origin of both histologies from a common B-cell clone.

Histologic transformation in extranodal non-Hodgkin's lymphoma

Histologic transformation in the course of non-Hodgkin's lymphoma (NHL) has been reported to occur in 18 to 30% of the cases. Less favorable prognosis in cases with initial low grade malignancy followed by emergence of high grade malignancy has been previously described. In the previous literature, the histologic transformation has been examined mostly in nodal NHL. In the present study, histologic transformation in the course was investigated on 20 cases with early extranodal NHL. All these 20 cases were diffuse lymphomas, and were composed of 7 cases with low grade malignancy and 13 cases with high grade malignancy. Histologic transformation was not observed in any of these cases. These findings indicate that the frequency of histologic transformation is much lower in extranodal NHL than in nodal NHL. The prognostic significance of these findings is also discussed.

2. Lymphocyte surface marker studies in lymphoma and leukemia

In the past decade, studies of the markers expressed on the surface of malignant lymphocytes from patients with lymphoma and leukemia have greatly expanded our knowledge and understanding of these disorders. In addition, the results obtained have allowed individual cases to be categorized to prognostic groups, thus influencing the choice of therapy. These studies should now be considered routine in the evaluation of patients with lymphoid leukemias and lymphomas.

J-chain-producing immunoblastic lymphoma in a case of Richter's syndrome. Immunohistochemical evidence for a gradual malignant transformation of a single B-cell clone and flow cytophotometric data

A 66-year old male with Richter's syndrome died 52 month after diagnosis of chronic lymphocytic leukaemia (CLL). The clinical course was characterized by a marked IgM hypoglobulinaemia which paralleled a chronically relapsing Herpes simplex infection. Autopsy showed a large retroperitoneal and intraabdominal tumour mass and well defined supradiaphragmatic lymphomas. Histological examination revealed a composite tumour consisting of CLL B-cell type (B-CLL) and immunoblastic malignant lymphoma of B-cell type (B-IbL). The lymphocytes bear mu-chains on their surface and to a lesser extend within their cytoplasm, the obviously defective immunoblasts produce J chains exclusively. Flow cytophotometric data seem to indicate an identical diploid stem line of the two tumours. The majority of the cells are in G0/1 phase. The CLL rarely produces mitoses, however, the IbL has a mitotic rate of 7% and a considerable proportion (33%) of cells in the phase of DNA-synthesis. This is the fourth malignant lymphoma and the second immunoblastic lymphoma to be reported that produces J chain in the absence of immunoglobulin.

Multiple histologic subtypes of non-Hodgkin's lymphoma: clinical and pathologic features

Twenty patients with non-Hodgkin's lymphoma (NHL) had different histologic subtypes of NHL in multiple sites or in a single tumor mass either at the time of their initial biopsy and staging (13 patients) or in the course of their disease (seven patients). These 20 cases represent 3.7% of all patients with NHL seen at the University of Chicago between January 1968 and May 1979. The five-year actuarial survival rate for all 20 patients was 68%. For those 13 patients who had multiple histologic subtypes at the initial workup, the five-year survival rate was 45%; for the seven patients who developed a new histologic subtype later in the course of the disease, the five-year survival rate was 85%. In the latter group of patients, however, the initial biopsy specimens demonstrated better prognostic subtypes, and the median survival from the time of diagnosis of a new, less favorable histologic subtype averaged only four months. These findings indicate that the prognosis is related to the least favorable histologic subtype present, unless this is only a minor component of a composite lymphoma or is limited to one extranodal site.

Malignant lymphoma supervening in chronic lymphocytic leukemia and related disorders. Richter's syndrome: a study of 25 cases

Richter's syndrome (RS) has been defined as "histiocytic" lymphoma (HL) or Hodgkin's disease (HD) supervening in the course of chronic lymphocytic leukemia (CLL) and related disorders. The clinical, histologic, and immunologic findings in 25 cases (11 women, 14 men) of RS are presented. The initial diagnosis was CLL in 19 cases, diffuse well-differentiated lymphocytic lymphoma in 2 cases, and Waldenstrom's macroglobulinemia in 4 cases. The interval between the initial diagnosis and that of RS ranged from 0 (two cases) to 120 months (median 49 months). At the time of diagnosis of RS, the initial lymphoproliferative disorder was in apparent complete remission in only two cases. The lymphoma was disseminated in at least 18 cases. The overall median survival was four months, but complete remission was achieved in six cases and has been maintained for 15 to 77 months. In four of these six cases, the RS was localized. The histologic diagnosis of HD was made in only two cases. In the other 23 cases, the diagnosis was HL, but in five of these cases, the proliferation was heterogeneous and was considered as an early aspect of HL. Immunologic studies of lymph node cell suspensions were performed in seven cases. In all cases, the B-lymphocytic origin of the lymphoma cells could be ascertained. Detailed studies in four cases showed that lymphoma cells carried SIg of the same isotype and light chain type as that of SIg detected on CLL cells or of monoclonal serum Ig. In these cases, the lymphoma was actually related to the initial B-cell chronic lymphoid disease.

Richter's syndrome in chronic lymphocytic leukemia

Over an 18-year period a distinctive large cell lymphoreticular neoplasm (Richter's transformation) developed in 9 patients with chronic lymphocytic leukemia. Clinical findings at the onset of Richter's transformation were remarkably uniform and consisted of the abrupt onset of fever, marked asymmetric lymphadenopathy with the formation of masses, splenomegaly, and hepatomegaly. All patients underwent rapid clinical deterioration followed by death within six and a half months. Earliest infiltrates of large lymphoreticular cells were identified in the lymph nodes in 3 of 4 patients and the bone marrow in 3 of 9 patients, while no patient had peripheral blood involvement. Autopsy examinations revealed extensive infiltrates of large lymphoreticular cells, predominantly in bone marrow, lymph nodes, liver, spleen, but also in kidney, lung, and gastrointestinal tract. In each case, these large lymphoblast-like and pleomorphic lymphoreticular cells were admixed with mature-appearing lymphocytes and intermediate forms (prolymphocytes). Electron microscopic and immunoperoxidase studies provided additional evidence that this highly aggressive lymphoreticular neoplasm represents a transformation or dedifferentiation of chronic lymphocytic leukemia.

Richter's syndrome with identification of marker chromosomes

A case is presented of a man with Richter's syndrome with diffuse histiocytic lymphoma following a ten-year history of untreated chronic lymphatic leukemia. He did not respond to therapy. The lymphoma cells had 61 chromosomes with aneuploidy of 13 chromosomes and 11 structurally altered chromosomes. Only chromosomes 8, 9, 12, 14, and 18 were diploid and without abnormality. Significantly, part of chromsome 1q was duplicated as in the partial trisomy of 1q reported to characterize a number of hematologic neoplasms. A large marker chromosome with subterminal centromere was a tandem duplication of chromosome 4q.

Human chronic lymphocytic leukaemia. Surface markers and activation of lymphocytes

Cell surface markers and the responses of lymphocytes to T- and B-cell mitogens were studied in 10 patients with CCL. T cells were identified as cells rosetting with sheep red blood cells (SRBC), and S-Ig was used as a marker for B lymphocytes. Most cells from all patients had a detectable amounts of S-Ig, and the percentage of cells rosetting with SRBC was low in all cases. Of the lymphocytes from these patients, 3-74% (mean 33%) were positive for the acid esterase (ANAE), which has been claimed to be a T-cell marker. However, some patients had cells that were positive for both S-Ig and ANAE. Acid esterase staining is therefore not a valid T-cell marker in chronic lymphocytic leukaemia. In cultures containing the T-cell mitogen leucoagglutinin (LA) and the T- and B-cell mitogen pokeweed mitogen (PWM) the reactivity of the lymphocytes was low. The cells responded vigorously to the T- and B-cell mitogen protein A (PA); however, the response was serum-dependent, being strong in a culture medium containing foetal calf serum (FCS), but impaired in the presence of human AB serum. Only 1 patient had cells that responded to the B-cell mitogen LPS.

Immunologic characterization of ocular adnexal lymphoid neoplasms

We correlated the light microscopic features of ten ocular adnexal lymphoid neoplasms with the results of selected immunologic and histochemical lymphocyte marker studies. The lesions were divided into three histomorphologic patterns: inflammatory pseudotumor, reactive follicular hyperplasia, and malignant lymphoma. The six inflammatory pseudotumors, and reactive follicular hyperplasia, despite diverse histomorphology, were immunologically polyclonal and consisted of from 45 to 73% T cells and 27 to 60% B cells, the B cells being polyclonal with respect to light chain determinants. The four malignant lymphomas were immunologically monoclonal. Each consisted of a predominant B-cell proliferation, greater than 50% of the cells, which were monoclonal with respect to surface light chain determinants. No T-cell proliferations were observed. Our preliminary data indicate that, as in systemic lymphoid neoplasms, benign reactive lymphoid hyperplasias are immunologically polyclonal whereas malignant lymphomas are immunologically monoclonal. The systematic application of immunologic and histochemical techniques to the study of ocular adnexal lymphoid neoplasms may elucidate the natural history of these lesions.