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B-cell maturation antigen (BCMA)-specific chimeric antigen receptor (CAR) T-cell therapies have shown efficacy in relapsed/refractory multiple myeloma (RRMM). Because the non-human originated antigen-targeting domain may limit clinical efficacy, we developed a fully human BCMA-specific CAR, CT103A, and report its safety and efficacy in a phase 1 trial. Eighteen consecutive patients with RRMM, including 4 with prior murine BCMA CAR exposures, were enrolled. CT103A was administered at 1, 3, and 6 × 106 CAR-positive T cells/kg in the dose-escalation phase, and 1 × 106 CAR-positive T cells/kg in the expansion cohort. The overall response rate was 100%, with 72.2% of the patients achieving complete response or stringent complete response. For the 4 murine BCMA CAR-exposed patients, 3 achieved stringent complete response, and 1 achieved a very good partial response. At 1 year, the progression-free survival rate was 58.3% for all cohorts and 79.1% for the patients without extramedullary myeloma. Hematologic toxicities were the most common adverse events; 70.6% of the patients experienced grade 1 or 2 cytokine release syndromes. No immune effector cell-associated neurotoxicity syndrome was observed. To the cutoff date, CAR transgenes were detectable in 77.8% of the patients. The median CAR transgene persistence was 307.5 days. Only 1 patient was positive for the anti-drug antibody. Altogether, CT103A is safe and highly active in patients with RRMM and can be developed as a promising therapy for RRMM. Patients who relapsed from prior murine BCMA CAR T-cell therapy may still benefit from CT103A. This trial was registered at http://www.chictr.org.cn as #ChiCTR1800018137., (© 2021 by The American Society of Hematology.)

Plasma cell neoplasms (PCNs), comprising plasma cell myelomas (PCMs) and plasmacytomas, which occur after solid organ transplantation, represent rare subtypes of monomorphic post-transplant lymphoproliferative disorders (M-PTLDs). Data regarding the clinical and pathological features of post-transplant (PT)-PCMs are limited. To gain a better understanding of disease biology, we performed comprehensive immunophenotypic analysis, reviewed cytogenetic analysis results and evaluated clinical outcomes of PT-PCMs diagnosed and treated at our institution. Fifteen PT-PCM (M: F - 4:1) and two PT-MGUS (two males) cases were identified. The median age of PT-PCM patients was 68 years (29-79 years) and PCMs presented at a median of 9.7 years (0.5-24.7 years) after transplantation. The PT-PCMs accounted for 11.6% of all M-PTLDs and the period prevalence was 9/3108 (0.29%), 3/1071 (0.28%), 2/1345 (0.15%) and 1/878 (0.11%) post kidney, heart, liver and lung transplantation. Lytic bone disease was observed in 1/11 (9%) patients. Marrow plasma cell infiltration ranged from 10%-70% (median 20%), with 10/15 (67%) and 5/15 (33%) cases manifesting immature and plasmablastic morphology. The immunophenotype of all cases and cytogenetic abnormalities, identified in 60% of cases, were similar to multiple myeloma (MM) of immunocompetent individuals. All PT-PCMs were EBER negative. Ten of 11 (91%) patients with active MM were treated, all with proteasome inhibitor-based therapy. Treatment response and 5-year overall survival (54.5%) was comparable to MM of immunocompetent individuals. However, the survival of patients with plasmablastic PCMs was inferior to those with immature PCMs. 0ur findings indicate PT-PCMs to be predominantly late onset PTLDs that have similar clinicopathologic characteristics as conventional MM., (© 2020 Wiley Periodicals LLC.)

This multicenter retrospective study included 101 patients (median age 62 years) with secondary plasma cell leukemia (sPCL). The median time from initial multiple myeloma diagnosis to sPCL was 31 months. Fifty-five out of 72 patients (75%) who received any therapy were treated with immunomodulators (IMiDs) and/or proteasome inhibitors (PIs), and 14/72 (19%) underwent salvage autologous stem cell transplantation (ASCT). The overall response rate in patients who received ASCT or PI (either alone or in combination) was higher than in those who did not (93% vs. 36% and 60% vs. 30%, respectively). The median overall survival (OS) in patients who received therapy was 4.2 months (95% CI: 1.3; 8.0) with a 1-year OS of 19%. Platelet count ≤100 × 10 9 /L at sPCL diagnosis was the only independent predictor of a poorer OS in treated patients (HR = 3.98, p = .0001). These findings suggest that patients with sPCL may benefit from salvage ASCT- and PI-based regimens.

IgM multiple myeloma (MM) is a rare entity representing approximately 0.5% of all MM. It should be distinguished from malignant neoplasms of B cells with plasmacytic differentiation such as Waldenstrom macroglobulinemia (WM) and marginal zone lymphoma with plasmacytic differentiation. Plasma cell leukemia (PCL) is a rare and aggressive variant of MM characterized by the presence of circulating plasma cells. We present a case report of a patient who presented with IgM MM in primary PCL phase with high-risk cytogenetics. To our knowledge, this is the first reported case of IgM MM with primarily leukemic presentation in the era of novel drugs. We demonstrate that it is important to distinguish IgM MM from WM and review the data from clinical trials that was used to devise a treatment strategy for this high-risk patient. This case adds to the understanding of the diagnosis and management of IgM MM in leukemic phase., (© 2017 by the Association of Clinical Scientists, Inc.)

Plasma cell leukemia (PCL) is a rare, but very aggressive, plasma cell dyscrasia, representing a distinct clinicopathological entity as compared to multiple myeloma (MM), with peculiar biological and clinical features. A hundred times rarer than MM, the disease course is characterized by short remissions and poor survival. PCL is defined by an increased percentage (>20%) and absolute number (>2 × 10 9 /l) of plasma cells in the peripheral blood. PCL is defined as 'primary' when peripheral plasmacytosis is detected at diagnosis, 'secondary' when leukemization occurs in a patient with preexisting MM. Novel agents have revolutionized the outcomes of MM patients and have been introduced also for the treatment of PCL. Here, we provide an update on biology and treatment options for PCL.

Introduction: Primary plasma cell leukemia (PPCL) is a rare and aggressive variant of multiple myeloma. The introduction of novel agents and modern technologies has recently partially changed the clinical and biological scenario of this malignancy, allowing limited, but not negligible, progresses. Areas covered: We will discuss: the complex landscape of genetic alterations in PPCL, derived from conventional and high-throughput technologies; the best available treatments for PPCL; the possible future therapeutic perspectives. Expert commentary: PPCL requires an immediate and intensive multi-phase treatment with short therapy-free intervals, which should include novel agents and autologous stem cell transplantation in eligible patients. Allogeneic transplantation should be considered in selected cases. In older and/or frailer individuals, personalized approaches should be applied. Integrated treatments with next generation proteasome inhibitors/IMIDs and monoclonal antibodies are currently planned or under investigation. The identification of novel genomic biomarkers may be potentially helpful for risk stratification and future personalized therapies.

Primary plasma cell leukemia (PPCL) is an aggressive and rare variant of multiple myeloma (MM), characterized by peculiar adverse clinical and biological features. Though the poor outcome of PPCL has been slightly improved by novel treatments during the last 10 years, due to the limited number of available studies in this uncommon disease, optimal therapy remains a classic unmet clinical need. Anyway, in the real-life practice, induction with a bortezomib-based three-drug combination, including dexamethasone and, possibly, lenalidomide, or, alternatively, thalidomide, cyclophosphamide, or doxorubicin, is a reasonable first-line option. This approach may be particularly advisable for patients with adverse cytogenetics, hyperleucocytosis, and rapidly progressive disease, in whom a fast response is required, or for those with suboptimal renal function, where, however, lenalidomide should be used with caution until renal activity is restored. In younger subjects, leukemia/lymphoma-like more intensive regimens, including hyperfractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone or continue-infusion cisplatin, doxorubicin, cyclophosphamide, and etoposide, may be also combined with bortezomib +/- thalidomide. Treatment must be started immediately after a diagnosis of PPCL is made to avoid the risk of irreversible disease complications and, in such a context, the prevention of tumor lysis syndrome is mandatory. In patients eligible for autologous stem cell transplantation (AuSCT), other alkylating agents, in particular melphalan, should be initially avoided in order to allow adequate collections of CD34+ peripheral blood stem cells (PBSC). A combination of lenalidomide and dexamethasone may be a valuable alternative option to manage older or unfit patients or those with slower disease evolution or with signs of neuropathy, contraindicating the use of bortezomib. Patients not suitable for transplant procedures should continue the treatment, if a response occurs and if tolerated, considering the possibility of a prolonged maintenance therapy. AuSCT should be pursued in all eligible patients less than 65 years old who achieve a significant response after a short course of induction treatment. PBSC collection should reach a threshold of at least 5 × 10(6) CD34+ PBSC/kg using cyclophosphamide plus G-CSF and adding the mobilizing agent plerixafor, if necessary. High-dose melphalan (HDM) (200 or 140 mg/m(2), according to age and renal function) remains the preferable conditioning regimen. A second AuSCT should be always considered, even in patients achieving complete response (CR) after the first AuSCT, as the short progression-free survival (PFS) generally seen in PPCL suggests the persistence of a relevant burden of residual disease; this provides a strong rationale for the use of post-transplantation therapies in PPCL to improve depth of response, to maintain remission, and, possibly, to increase survival, though consolidation and/or maintenance strategies with novel agents, whose efficacy has been well demonstrated in MM, have not been still extensively evaluated in PPCL. The search of a suitable donor should start as soon as possible and an allogeneic stem cell transplant (AlloSCT) with a myeloablative conditioning (MAC) regimen discussed with younger patients responsive to induction therapy and with poor prognostic parameters at diagnosis. A sequence of AuSCT followed by reduced intensity conditioning (RIC) or non-myeloablative (NMA) AlloSCT may be considered in selected cases. Salvage therapies for relapsed/refractory disease, especially using new drugs not employed at diagnosis, are sometimes effective in the short term, but a rapid relapse is still generally the rule; AlloSCT in relapsed and eligible patients with sensitive disease after salvage treatments is, therefore, recommended.

Plasma cell leukemia (PCL) is a rare and aggressive plasma cell disorder, with poor outcome. Bortezomib-based regimens (BBR) are highly effective in myeloma, but there is limited information about their efficacy and safety in PCL. Thus, we retrospectively collected data from 42 consecutive PCL patients (25 with primary PCL-pPCL and 17 with secondary PCL-sPCL) to explore the role of BBR in this entity. BBR were administered in 29 of 42 patients, while 6 of 25 patients with pPCL underwent autologous transplantation. Objective response (≥partial response) was significantly higher in patients treated with BBR versus conventional therapies (69% vs. 30.8%, P = 0.04); 27.5% of patients treated with BBR achieved at least very good partial response (vgPR). The highest ORR was observed in pPCL patients treated with BBR (88.9%; ≥vgPR: 33.3%). In BBR-group, grade 3 of 4 hematological, neurological and renal toxicity and neutropenic infections were observed in 41.4%, 7%, 3.4%, and 31%, respectively. With a median follow-up of 51 months, median overall survival (OS) for patients treated with BBR versus conventional therapies was 13 versus 2 months (P < 0.007). Median OS of patients with pPCL and sPCL treated with BBR was 18 and 7 months, respectively (P < 0.001). In the multivariate analysis normal PLTs, treatment with BBR and high quality response were the only powerful predictors for survival. Our study carrying the longest reported median follow-up, demonstrated that treatment of PCL with BBR induces high response rates and prolongs survival over conventional therapies, regardless of additional autologous transplantation rescue or established high risk features, with manageable toxicity., (Copyright © 2013 Wiley Periodicals, Inc.)

Cancer cells are characterized by having chromosomal abnormalities. The number of aberrations and the specific chromosomes affected are likely correlated with tumor progression. In this study, we analyzed the karyotype of 126 plasma cell leukemia (PCL) patients to identify the most frequently occurring imbalances and to design a model of karyotypic evolution. The Mitelman database of chromosome was searched and abnormal karyotypes were assessed. The main clones were analyzed and chromosomal gains and losses were used to design a model of genetic acquisition based on the calculation of a variable called time to occurrence. Our comprehensive study of genetic abnormalities of a large number of PCL karyotypes suggests that PCL is mainly characterized by the presence of whole chromosome losses as well as IgH rearrangements which is similar to that observed in non-hyperdiploid multiple myeloma (MM). Temporal analysis suggests that most PCL have around 10 abnormalities at diagnosis. It is possible that accumulation of abnormalities such as 17p13 (TP53) and 1p losses may trigger the extramedullary features of PCL. Our study demonstrates that cytogenetics is a valuable tool to evaluate the role of genetic imbalances on karyotypic evolution by using a mathematical model., (© 2011 John Wiley & Sons A/S.)

Extramedullary plasma cell cancers, such as plasma cell leukaemia (PCL) and multiple extramedullary plasmacytomas (MEP) are very aggressive malignancies. These can be primary (de-novo) or secondary due to progressive prior multiple myeloma (MM). Recent reports suggest an increase in incidence of these disorders. Compared to MM, organ invasion is common in PCL, while soft tissue tumors involving the head, neck or paraspinal area are common sites for MEP. Markers of poor prognosis are frequently observed in these extramedullary forms of plasma cell cancers, and survival is significantly inferior compared to patients with MM. Conventional chemotherapeutic and radiotherapy approaches have been employed with variable results. Even high dose chemotherapy with autologous stem cell rescue has not been able to demonstrate consistent improvement in survival outcome. Although not specifically evaluated, novel anti-plasma cell agents, such as the proteasome inhibitor bortezomib, and immunomodulatory drugs, such as lenalidomide, appear to be active against these aggressive cancers. Clinical and translational research directed at improved understanding of disease biology and development of novel therapeutics is urgently needed.

Background: Bortezomib (Velcade) is a proteasome inhibitor used in the treatment of myeloma and other blood dyscrasias. We report the cases of two patients who developed a peculiar toxic rash suggestive of Sweet's syndrome while receiving bortezomib; one patient also presented giant mucous membrane ulcerations., Patients and Methods: Case 1: bortezomib treatment was started in a 62-year-old man for mantle cell lymphoma. Ten days after the first treatment cycle, giant, painful oral ulcerations were noted but they resolved spontaneously. One week after the second cycle, further oral ulceration appeared, this time with a papulonodular skin rash. Histology showed neutrophilic dermal infiltrates in the skin with predominantly lymphocytic inflammation of the oral mucosa. Bortezomib was stopped and all lesions resolved with colchicine treatment. Case 2: a 46-year-old woman was receiving bortezomib treatment for plasma cell leukemia. A febrile skin rash appeared two days after the first treatment cycle but resolved spontaneously. After the first bortezomib injection during the next cycle, painful papules and nodules appeared on the trunk. The skin biopsy results were consistent with Sweet's syndrome. The lesions disappeared spontaneously. Dexamethasone was administered concomitantly with bortezomib in the ensuing cycles and there was no relapse of the skin lesions., Discussion: Bortezomib-induced skin lesions are common and usually do not justify treatment withdrawal. Published observations of bortezomib-induced eruption occasionally show clinical and histological features of Sweet's syndrome, but there has been no mention of oral mucosal ulcerations. In our cases, these could be related to bortezomib-induced neutrophilic dermatosis.

The most aggressive and rare manifestation of multiple myeloma is plasma cell leukaemia (PCL). While secondary form of PCL represents those heavily pretreated cases when leukaemic transformation develops terminally after intensive chemotherapy in patients with multiple myeloma, primary cases are characterized by leukaemic symptoms present at diagnosis. The secondary form has a rapid progression. The management of PCL is still unsolved. The authors present a case of a patient with non-secretory multiple myeloma who had developed plasma cell leukaemia after peripheral stem cell transplantation. PAD (bortezomib, doxorubicin, dexamethasone) treatment resulted in complete remission and 9-month survival of the patient. Previous case reports in the literature and our experience have revealed PAD protocol to be well tolerated and effective in PCL. Combination of PAD treatment with autologous and/or allogenic stem cell transplantation might further improve patients' outcome.

The St. Vincent's Comprehensive Cancer Center (SVCCC) has a large multiple myeloma program in downtown New York City. The laboratory at SVCCC is an integral part of the diagnosing and monitoring of its myeloma patients. Circulating plasma cells are not a common finding in multiple myeloma. Being able to detect plasma cells in peripheral blood is important because they are a prognostic indicator that correlates with disease progression. Furthermore, the peripheral blood plasma cell population can demonstrate morphologic variability. Immature plasma cells, both plasmablasts and proplasmacytes are associated with more aggressive disease and shortened survival. We encountered 3 multiple myeloma patients with circulating immature plasma cells that appeared as distinct populations on our hematology analyzer's automated white blood cell (WBC) differential. The immature plasma cells, given their unique cellular characteristics, appeared in a common place within the WBC differential scatterplot in each patient. In our laboratory, we have utilized this common graphic pattern to screen for immature plasma cells. This pattern has proven to be a useful tool in our large population of multiple myeloma patients. We have also used examination of the scatterplots in other hematologic malignancies such as chronic lymphocytic leukemia. Using this review policy, the laboratory has been able to achieve a smear review of 25% in our highly abnormal patient population.

Plasma cell leukemia (PCL) is a rare disease and is the least common variant of multiple myeloma accounting for 2-3% of all plasma cell dyscrasias. We report a patient who presented with history of high grade fever, weakness, palpitations, loss of appetite, bone pains and mental confusion for twenty days. Initial evaluation revealed plasmacytosis with blood plasma cell count of 5184/cumm. His hemoglobin (Hb) was 11.3 gm/dl, platelets were 75000/cumm and total leucocyte count (TLC) was 21600/cumm (24% plasma cells). Bone marrow examination revealed >60% plasmablasts. Serum LDH was high at 3117 U/L and serum calcium was also elevated at 13.9 mg/dl. A diagnosis of PCL was made and the patient was started on treatment for hypercalcaemia with Melphalan/Prednisolone regime along with supportive care. Patient deteriorated very rapidly despite treatment and died on the eighth day. A detailed report of this case and a review of PCL is presented here.

Plasma cell leukemia is considered as the leukemic variant of multiple myeloma. It is a rare entity. There are two forms: a secondary one following a known myeloma, the diagnosis of which is easy, and a primary one arising without a preceding phase of multiple myeloma. The diagnosis of the latter form is more difficult, a differential diagnosis has often to be discussed with other lymphoproliferative diseases. Prognosis is poor. We report 2 cases of secondary plasma cell leukemia diagnosed over ten years, among 59 of multiple myeloma cases. We describe the epidemiologic, clinical, biological and evolutionary characteristics.

Plasmablastic leukemia (PL) as a complication of human herpes virus 8 (HHV8)-associated Castleman's disease is marked by a rapid and fatal outcome. In patients with AIDS, survival of 7 to 14 days after diagnosis has been reported. Prompt splenectomy and chemotherapy might lead to a significant survival benefit. Here we report a case of long-term survival in a patient with AIDS and multicentric Castleman's disease (MCD) complicated by PL.

The term "monoclonal gammopathy" (MG) includes a group of clonal plasma cell disorders, which show heterogeneous clinical behavior. While multiple myeloma (MM) and plasma cell leukemia (PCL) are incurable malignant diseases, most patients with MG of undetermined significance (MGUS) show an indolent/benign clinical course. Evidence has accumulated which supports the role of the bone marrow microenvironment in MG. Accordingly, the survival, drug-resistance and proliferation of MM cells have been shown to be largely dependent on a supportive microenvironment. Among the different environment-associated parameters, those related to the status/activity of the immune system are particularly relevant. This review focuses on the different ways clonal plasma cells (PC) interact with the immune system in different models of MG, to characterize crucial events in the development and progression of MG. These advances may support the design of novel therapeutic approaches in patients with MG.

Plasma cell leukemia (PCL) is a rare aggressive lymphoproliferative disease with a short median survival and a very poor prognosis. We report the case of a 63-year-old man who developed a PCL after 5 years of chemotherapy with hydroxyurea and busulphan for Essential thrombocythemia (ET). The karyotype showed a deletion of chromosome 7 and the plasma cells cytofluorimetric examination revealed a high expression of Multidrug Resistance related P-glycoprotein (PGP). After the second cycle of VAD chemotherapy the patient had a severe pneumonia and died with refractory PCL. This is a rare example of the coexistence of a chronic myeloproliferative and lymphoproliferative diseases in the same patient, and to the best of our knowledge, the first reported in the literature involving PCL and ET. Moreover, this case shows the possibility of secondary malignancies developing in patients treated with busulphan and hydroxyurea for chronic myeloproliferative disorders.

Syndecan-1 (CD138) is a transmembrane heparan sulfate-bearing proteoglycan expressed by most myeloma plasma cells that regulates adhesion, migration, and growth factor activity. In patients with myeloma, shed syndecan-1 accumulates in the bone marrow, and high levels of syndecan-1 in the serum are an indicator of poor prognosis. To test the effect of soluble syndecan-1 on tumor cell growth and dissemination, ARH-77 B-lymphoid cells were engineered to produce a soluble form of syndecan-1. Controls included vector only (neo)-transfected cells and cells transfected with full-length syndecan-1 complementary DNA that codes for the cell surface form of syndecan-1. Assays reveal that all 3 transfectants have similar growth rates in vitro, but cells expressing soluble syndecan-1 are hyperinvasive in collagen gels relative to controls. When injected into the marrow of human bones that were implanted in severe combined immunodeficient mice, tumors formed by cells expressing soluble syndecan-1 grow faster than tumors formed by neo-transfected cells or by cells expressing cell surface syndecan-1. In addition, cells bearing cell surface syndecan-1 exhibit a diminished capacity to establish tumors within the mice as compared with both neo- and soluble syndecan-1-transfected cells. Tumor cell dissemination to a contralateral human bone is detected significantly more often in the tumors producing soluble syndecan-1 than in controls. Thus, high levels of soluble syndecan-1 present in patients with myeloma may contribute directly to the growth and dissemination of the malignant cells and thus to poor prognosis.

Transformation of chronic lymphocytic lymphoma into plasma cell leukaemia is extremely rare. The diagnosis is made on if the circulating plasma cells in peripheral blood is in excess of 2000 cells/mm3.

Multiple myeloma (MM) is a plasma-cell malignancy characterized by marked epidemiological, biological, and clinical heterogeneity. The goal of this study was to find a genetic basis for this heterogeneity. Using fluorescence in situ hybridization, we analyzed a prospective cohort of 901 patients with various plasma-cell disorders--monoclonal gammopathies of undetermined significance, smoldering MM, MM, and primary plasma-cell leukemia--for genetic abnormalities involving the 13q14 and 14q32 chromosomal regions; the patients were consecutively enrolled in the Intergroupe Francophone du Myélome clinical trials, We performed statistical analyses comparing these chromosomal abnormalities in terms of immunological (ie, immunoglobulin types and light-chain subtypes) and clinical status and, to some extent, prognostic features. It was found that 14q32 translocations and del(13) are the most frequent chromosomal abnormalities, observed in 75% and 45% of the patients, respectively, and are not randomly distributed, but interconnected. Second, correlations between them allowed us to define 4 major genetic categories of patients: (1) patients lacking any 14q32 abnormality (25%) and generally also lacking del(13); (2) patients presenting either t(4;14) or t(14;16), almost always associated with a del(13) (15% of patients); (3) patients with other 14q32 abnormalities and presenting del(13) (25%); and (4) patients with other 14q32 abnormalities but not presenting del(13) (35%). Third, we show that this genetic stratification is highly correlated with immunological status and clinical presentation and with some major prognostic factors. For the first time, this study gives genetic support to the heterogeneity observed in patients with MM and demonstrates that the 14q32 and 13q chromosomal abnormalities are not randomly distributed. The strong correlations we found might be the basis for a novel genetic classification of MM, as has been previously demonstrated for leukemias and lymphomas. Furthermore, our study supports different models for MM oncogenesis.

Activation of telomerase is essential for in vitro cellular immortalization and tumorigenesis. In the present study, we investigated telomerase activation and its implications in plasma cell dyscrasias including monoclonal gammopathy of undetermined significance (MGUS), multiple myeloma (MM) and plasma cell leukaemia (PCL). All 5 patients with MGUS exhibited normal levels of telomerase activity in their plasma cells. Elevated telomerase activity was found in the samples from 21/27 patients with MM and 4/4 with PCL. In addition, 4 myeloma cell lines all expressed high levels of telomerase activity. The expression of telomerase reverse transcriptase (hTERT) and telomerase RNA template (hTER) was positively associated with the levels of telomerase activity in MM/PCL. Tankyrase expression was upregulated, concomitant with the induction of hTERT and activation of telomerase in MM/PCL. The present findings indicate that MGUS cells may not be immortalized and that activation of telomerase plays a role in the malignant transformation from MGUS to MM., (Copyright 2001 Cancer Research Campaign.)

Two cases of plasma cell leukaemia--a rare form of leukaemia are described. Both cases presented with anaemia and hepatosplenomegaly. Investigations revealed leucocytosis with increased plasma cells (> 20%). Skeletal survey revealed a few osteolytic lesions in both cases.

We describe a patient with multiple myeloma who was treated with intensive therapy and autologous blood cell transplantation as her first-line treatment. The disease relapsed 3 months after the transplant as plasma cell leukemia and the patient succumbed in 4 weeks. We suggest that an aggressive plasma cell clone may be selected during the course of intensive treatment. Complex karyotypic findings are also presented.

Growth factors or humoral agents can support haemopoiesis in various bone marrow disorders. They have the ability to act on multiple cell lineages and in myeloid cells, and the potential to act on the neoplastic equivalent of normal cells. Anaemia is a common feature of multiple myeloma seen in at least two-thirds of patients at presentation. Erythropoietin is increasingly being used with variable effect for the treatment of this anaemia, especially in cases associated with renal failure and in patients in whom blood transfusion may be undesirable or contraindicated. We describe a patient treated with recombinant erythropoietin who developed fulminating malignant transformation. The demonstration of erythropoietin receptors on a human myeloma cell line and the occurrence of the rare complication of plasma cell leukaemia in our patient stresses the need for caution and invites detailed clinical and laboratory studies before its general use.

Plasma cell tumors (plasmacytomas-PCT) of the bone, or extramedullary PCT, may be diagnosed in patients with or without the diagnostic criteria for systemic multiple myeloma (MM). The reason for the local development of these tumors is not clear. Recent reports emphasize the contribution of CT and MRI in the detection of bone lesions and their expansion into the soft tissues. We report the development of PCT in nine patients with MM under maintenance treatment with alpha-IFN, of whom six had no evidence of systemic relapse and three had indications of early relapse. The PCT were located in the pelvis (4), thoracic (3), cervical (1), and lumbar (2) spine and in 8/9 cases were not demonstrable on plain X-rays. These observations suggest that frequent screening with advanced imaging techniques may detect local disease expansion in asymptomatic patients. Early application of radiochemotherapy may improve prognosis.

Among 750 previously untreated patients with multiple myeloma, 27 (4%) presented with plasma cell leukaemia. All but one patient had high tumour mass and, when compared with comparable patients without leukaemia, more frequent extraosseous involvement, thrombocytopenia, high serum lactate dehydrogenase and hypodiploid plasma cells. Most patients also had complex cytogenetic abnormalities. Treatment with standard melphalan-prednisone was ineffective, with a median survival of 2 months, but more intensive chemotherapy induced responses in approximately one-half of the patients, with a median survival of 20 months. Primary plasma cell leukaemia usually results from the proliferation and extramedullary expansion of immature plasma cells and requires prompt and intensive chemotherapy.

A retrovirus, known as salmon leukemia virus (SLV), was purified from farm-reared chinook salmon (Oncorhynchus tshawytscha) with plasmacytoid leukemia (PL). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis of purified SLV revealed the presence of 9 virus-associated polypeptides with molecular weights from 82 kDa to 15 kDa. Endoglycosidase digestion and alcian blue staining of viral polypeptides separated by SDS-PAGE, and immunoprecipitation experiments using hyperimmune antisera suggest that the non-glycosylated 27 kDa polypeptide may represent a capsid-associated protein and the 82 kDa glycoprotein may represent an envelope-associated protein, which appears to be composed of a 67 kDa protein moiety. Fish injected with PL-positive tissue homgenate developed a bimodal viremia, as indicated by the presence of cell-free, virus-associated reverse transcriptase activity and SLV in serum of fish from 1 to 3 wk post-injection and again from 7 wk on through the rest of the study. If horizontal transmission of SLV and PL occurs in infected chinook salmon, it is most likely to occur after the second viremic period begins.

A case of non-secretory multiple myeloma presenting as primary plasma cell leukaemia in a 65 year old woman is presented. Bone pain was the initial clinical manifestation. Laboratory analysis showed 20% of circulating immature plasma cells. Despite the presence of osteolytic lesions, no M-component could be demonstrated in serum protein electrophoresis, and serum and urine immunoelectrophoresis. Bone marrow aspirate demonstrated an 83% infiltration of plasma cells showing various degrees of immaturity. Immunofluorescence with monoclonal antisera demonstrated intracytoplasmic kappa light chains in a high percentage of plasma cells. Immature plasma cells without cellular capacity to synthesize and excrete complete immunoglobulins could be more aggressive, leading to an initial leukaemic process. Previous work regarding possible pathogenetic mechanisms, clinical and laboratory features, and response to treatment of this extremely rare association are reviewed.

A plasmacytoid leukemia of chinook salmon, Oncorhynchus tshawytscha, has recently been recognized in seawater netpens in British Columbia, Canada. The disease has occurred at several sites and has caused high mortality. Plasmacytoid leukemia is characterized by a generalized invasion of visceral tissues and the orbit of the eye by plasmacytoid cells. The disease was experimentally transmitted to healthy chinook salmon by i.p. injection of kidney tissue homogenates, but transmission with a cell-free filtrate was equivocal. In another experiment, chinook salmon, coho salmon, O. kisutch, sockeye salmon, O. nerka, rainbow trout, O. mykiss (or Salmo gairdneri), and Atlantic salmon, Salmo salar, were given injections of a tissue homogenate from affected chinook salmon. Ten wk after exposure, plasmacytoid leukemia was observed in all of the sockeye salmon and chinook salmon, one of ten Atlantic salmon, and none of the rainbow trout. Seven of the ten coho salmon examined at 10 wk had lesions suggestive of early development or a mild form of the disease. Multifocal areas of proliferating cells resembling plasmablasts were observed in the visceral fat, and the kidneys exhibited mild to moderate hyperplasia of the hematopoietic interstitium. Our studies support the hypothesis of an infectious etiology for plasmacytoid leukemia, but the agent, perhaps an oncogenic virus, has yet to be detected.

A 70-yr-old man with multiple myeloma IgD developed a plasma cell leukemia producing a serum IgD monoclonal peak and lambda light chains in the urine. When the serum and the urine were heated at 56 degrees C for 30 min both monoclonal bands disappeared. The precipitate failed to redissolve on heating to 100 degrees C. Ion exchange chromatography with a linear gradient of phosphate buffer, pH 8, 0.020-0.300 mol/l and column electrofocusing showed that the serum pyroglobulin was eluted with buffer concentration between 0.040-0.125 mol/l and had an isoelectric point of 5.02, while the pyroglobulin of the urine was eluted with 0.020-0.033 mol/l and had a pI = 7.16. The serum and urine pyroglobulins had a total antigenic community with their correspondent purified proteins. The isolated lambda chains did not change when they were heated at 56 degrees C for 30 min, nevertheless, the heated purified IgD shows some changes in its isoelectric point, molecular mass and antigenicity. These changes in the purified IgD suggest that the pyroprecipitability could be due to conformational features.

Five cases of acute plasmablastic leukemia (APL) in patients with a history of multiple myeloma (MM) are described. MM lasted from 3 months to 7 years. During APL, blast metaplasia in the bone marrow was detected in all the cases while in 3 patients it was found in the blood. The treatment ended in failure in 4 patients. The duration of APL in those patients did not exceed 6 months. In one of the patients, the duration of APL, in the presence of a partial remission, exceeded 19 months. The patient remains under observation.

A case of fatal, diffused plasmacytoma is presented. The picture also included leukaemia and is felt to be an example of plasma-cell leukaemia, as opposed to plasmacytoma in the light of the anatomical and clinical features of the onset and course: high and very pronounced plasma-cell leukocytosis, diffuse proliferation of the plasma cell series in the bone marrow, spleen and lymph nodes, infiltration of plasma cells in the parenchymal organs, extremely rapid progress with serious anaemia, haemorrhage, general organic involvement, high fever, and infection.