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Cancer patients occasionally have anemia with high mean corpuscular volume in addition to iron deficiency anemia. Secondary autoimmune hemolytic anemia (AIHA) following cancer is also observed with low frequency. To date, no causal mechanisms for these disease states have been reported. Here, we present the case of an 80-year-old woman with AIHA that was resistant to prednisolone. Further examinations revealed primary adenocarcinoma of the sigmoid colon and primary squamous cell carcinoma in the right lung. After resections of these tumors, her anemia partially improved until a colon cancer-derived metastatic tumor was detected in the left lung. Immunoprecipitation of erythrocyte membrane proteins with an autoantibody followed by mass spectrometry/Western blotting identified band 3 as the target of the autoantibody. Immunohistochemical analysis revealed ectopic expression of band 3 in the colon adenocarcinoma. To our knowledge, this is the first report that identifies the cause in a case of anemia without bleeding in a cancer patient and that defines a mechanism underlying secondary AIHA following cancer progression.

Objective Evaluation the activities of the dementia support care team (D-CAST). Method A total of 350 patients received intervention from the D-CAST from January 1, 2017, to December 31, 2017. At the beginning and end of the team intervention, the following items were evaluated: changes in the degree of life independence, period (days) from hospitalization to team intervention, request for team intervention, and duration of hospitalization. Results The average age of the 350 patients in this study was 81±9 years old. The major diseases causing hospitalization were heart failure in 94 patients (27%) and aortic valve disease for transcatheter aortic valve implantation (TAVI) in 45 patients (13%). The main reasons for requesting team intervention were cognitive impairment in 40% and delirium (prevention included) in 36%. Regarding the change in the degree of life independence, 29 people saw improvement (16%), 165 maintained their degree of independence (66%), and 46 experienced a decrease (18%). The team intervention was delayed as criteria for degree of independence of everyday life was lower for mild patients. Conclusion We need to learn how to assess dementia patients with relatively mild life independence (potentially including mild cognitive impairment).

We conducted a nation-wide survey of 112 adult Japanese patients who underwent reduced-intensity stem cell transplantation (RIST) from 1999 to 2002. Underlying diseases included indolent (n=45), aggressive (n=58) and highly aggressive lymphomas (n=9). Median age of the patients was 49 years. A total of 40 patients (36%) had relapsed diseases after autologous stem cell transplantation and 36 patients (32%) had received radiotherapy. RIST regimens were fludarabine-based (n=95), low-dose total body irradiation-based (n=6) and others (n=11). Cumulative incidences of grade II-IV acute graft-versus-host disease (GVHD) and chronic GVHD were, respectively, 49 and 59%. Cumulative incidences of progression and progression-free mortality were 18 and 25%, respectively. With a median follow-up of 23.9 months, 3-year overall survival rates were 59%. A multivariate analysis identified three significant factors for progression, which are history of radiation (relative risk (RR) 3.45, confidential interval (CI) 1.12-10.0, P=0.03), central nervous system involvement (RR 6.25, CI 2.08-20.0, P=0.001) and development of GVHD (RR 0.28, CI 0.090-0.86, P=0.026). RIST may have decreased the rate of transplant-related mortality, and GVHD may have induced a graft-versus-lymphoma effect. However, whether or not these potential benefits can be directly translated into improved patient survival should be evaluated in further studies.

当院の院内感染対策委員会では，感染防止研修会(1つのテーマを4回，年間5つのテーマについて実施)と病棟ラウンドによる直接指導を行っている．しかし，感染防止研修会において，勤務時間外の30分間の研修会に参加出来ない・疲労感から集中出来ない・覚えられないなどの問題が生じた．今回，上記の問題点を加味し，新たに「ミニ勉強会」と題し2006年8月より，全職員を対象に，各部署で具体的にポイントを絞りパソコンを使用した1テーマ10分以内での勉強会を実施した．ミニ勉強会と院内研修会の参加率の比較では，一部病棟と医師では若干の減少を認めたが，外来・手術室・コメディカルでは上昇した．ミニ勉強会終了後のアンケートの結果では，院内研修会と比較して，参加しやすい等の概ね良い評価が得られた．ミニ勉強会は，現場の都合に合わせ短時間に集中して行う教育方法としては効果的であったと考える．

A 60-year-old myelodysplastic syndrome patient underwent tandem cord blood transplantation. The primary cord blood graft was rejected, and human herpesvirus 6 (HHV6) encephalitis developed after engraftment of secondary cord blood. Polyuria and adipsic hypernatremia were observed during treatment of the encephalitis. The patient died of bacteremia caused by methicillin-resistant Streptococcus epidermis. HHV6 infection in the posterior pituitary was confirmed on autopsy, as was infection of the hippocampus, but not of the hypothalamus. This is the first case report of central diabetes insipidus caused by an HHV6 posterior pituitary infection demonstrated on a pathological examination.

To compare the different stem cell sources used in salvage transplantation for graft failure (GF) after cord blood transplantation (CBT), we retrospectively analyzed data of 220 patients who developed GF after undergoing CBT between January 2001 and December 2007 and underwent a second hematopoietic stem cell transplantation (HSCT) within 3 months. The donor sources for salvage HSCT were cord blood (n = 180), peripheral blood stem cells (PBSCs; n = 24), and bone marrow (BM; n = 16). The cumulative incidence of neutrophil engraftment on day 30 after the second HSCT was 39% with CB, 71% with PBSCs, and 75% with BM. Multivariate analysis revealed that PBSC and BM grafts were associated with a significantly higher engraftment rate than CB (hazard ratio [HR], 7.77; P < .001 and HR, 2.81; P = .016, respectively). Although the incidence of grade II-IV acute graft-versus-host disease was significantly higher in the PBSC group than in the CB group (HR, 2.83; P = .011), the incidence of 1-year nonrelapse mortality was lower in the PBSC group than in the CB group (HR, 0.43; P = .019), and 1-year overall survival was superior in the PBSC group compared with the CB group (HR, 0.45; P = .036). Our results suggest that PBSC is the preferable source of stem cells in salvage HSCT for GF after CBT.

We report a 62-year-old male who underwent non-myeloablative allogeneic peripheral blood stem cell transplantation (PBSCT) because of his life-threatening severe pancytopenia due to refractory Waldenström's macroglobulinemia. This therapy was performed safely and he made a marked recovery from his cytopenia that had not been improved with any other therapy. Bone marrow aspirates showed post-transplant mixed chimerism during engraftment, and became completely donor-derived after a series of GVHD symptoms, without subsequent donor lymphocyte infusion. Our results suggest that non-myeloablative allogeneic PBSCT could be a good alternative for patients suffering from multi-drug resistant Waldenström's macroglobulinemia.

The c-kit proto-oncogene encodes a receptor tyrosine kinase that is thought to play an important role in hematopoiesis. In a series of human acute myeloblastic leukemia (AML), the expression of the c-kit proto-oncogene and its product was studied by means of Northern blot and immunoblot analyses. The c-kit mRNA was expressed in 20 of 25 cases of AML, and in those cases the product of the c-kit proto-oncogene was detected by immunoblotting with anti-c-kit antibody. The expression of c-kit transcripts and protein was barely detectable in normal bone marrow cells as a control. The expression of c-kit transcript did not correlate with the French-American-British classification nor clinical manifestations. In 6 of 11 cases that expressed c-kit product, AML cells were found to proliferate in response to recombinant human stem cell factor (rhSCF), the ligand for c-kit, and the synergistic stimulation of AML cells was observed by rhSCF and granulocyte- macrophage colony-stimulating factor. Immunoblotting with anti- phosphotyrosine antibody showed that the c-kit receptor protein was detectably phosphorylated in 7 of 12 cases tested before the stimulation with rhSCF, while the rhSCF treatment resulted in an increased tyrosine phosphorylation of c-kit in AML cells. These results indicate that c-kit proto-oncogene is expressed in most cases of AML and is functional in terms of supporting proliferation.

Background: Bone marrow necrosis, a rare condition, characterized by necrosis of the medullary stroma and myeloid tissues of the bone marrow. The etiology is diverse, including hematopoietic malignancies. Case report: A 54-year-old male arrived by ambulance with collapse and high fever. On clinical examination, he had numerous petechiae and ecchymoses in the mouth and on the limbs. Laboratory findings revealed anemia and thrombocytopenia (WBC 15,140/μl, Hb 4.7g/dl, Plt 3.8X104/μl). A blood culture was positive for Staphylococcus aureus, diagnosed as septic shock, complicated by disseminated intravascular coagulation (DIC). When his medical condition was improved after treatment, blood examination showed pancytopenia (WBC 2,170/μl, blast 1.5%, Hb 9.2g/dl, Plt 1.1X104/μl). Multiple bone marrow aspiration displayed only small amount of the cells, which were difficult to be classified and were negative for peroxidase. Bone marrow biopsy showed marked bone marrow necrosis. During being treated for DIC, the abnormal cells were appeared in the peripheral blood, which were analyzed by flow cytometry and cytogenetics and eventually he was diagnosed as AML (M0, FAB classification). The sudden appearance of consolidation in the lungs by chest X-ray indicated leukemic cells infiltration into the lungs. His physical status was allowed chemotherapy consisting of cytarabine and aclarubicin only for the first four days of the standard protocol. Laboratory findings were improved, however, he suffered from repeated hemoptysis. Thoracic CT scan demonstrated diffuse alveolar damage and possible pneumonia. Despite of supportive treatment, his condition was complicated with chemotherapy associated-febrile neutropenia and he expired four weeks after admission. Conclusion: Bone marrow necrosis prognosis is related to underlying diseases and is generally poor. Therefore, multiple bone marrow aspirations and biopsies are needed to achieve appropriate diagnosis.

Abstract 1037 Background: In the IDSA guideline published in 2010 on the use of antimicrobial agents in neutropenic cancer patients, monotherapy with an anti-pseudomonal beta-lactam agent, such as cefepime (CFPM), carbapenem [meropenem (MEPM) or imipenem-cilastatin (IPM)], or piperacillin-tazobactam, is recommended as an empiric therapy for high risk febrile neutropenia (FN) patients. There have been few reports on the efficacy of cefozopran (CZOP), one of the 4thgeneration beta-lactams, in the treatment of such patients. We conducted an open-label randomized controlled study to evaluate the clinical efficacy of CZOP, MEPM, or IPM in high-risk FN adult patients with hematologic malignancies and solid tumors, using CFPM as a control. Methods: In this trial, 386 patients registered from 23 centers were randomized to receive either 4thgeneration beta-lactam (CFPM 2g, q12h IV or CZOP 2g, q12h IV) or carbapenem (MEPM 1g, q12h IV or IPM 1g, q12h IV). The primary endpoint was response to treatment defined as complete defervescence by day 7 with improvement in infection-related symptoms and laboratory findings. The clinical data were analyzed both by intention to treat and per protocol. We also evaluated the efficacy of each of the initial four drugs at days 3 to 5as a secondary endpoint. Results: 386 patients received the assigned antibiotic (CFPM: n=95, CZOP: n=98, MEPM: n=96, IPM: n=97) and 377 were evaluated for efficacy (CFPM: n=94, CZOP: n=95, MEPM: n=94, IPM: n=94). The 4 groups were comparable in terms of the baseline characteristics, including as age (median: 59 years (range: 17–87)), sex (male: n=215, female: n=171), body weight (median: 55 kg (range: 32–100)), underlying malignancy (leukemia: n=212 (54.9%), lymphoma: n=122 (31.6%), multiple myeloma: n=37 (9.6%), myelodysplastic syndrome: n=6 (1.6%), and other malignancy: n=9 (2.3%)), duration of initial antibiotic therapy (median: 7 days (range: 1–29)), median duration of severe neutropenia (neutrophil count < 100×106/L) (median: 6 days (range: 0–56)) and MASCC score (median: 21 (range:3–26)). Only neutrophil count at onset of IPM was significantly lower compared to the other treatments (CFPM: 38×106/L, CZOP: 35 x106/L, MEPM: 18×106/L, and IPM: 3×106/L, p=0.003). In intention-to-treat analysis, the response rates at day 7 were not significantly different among the four arms (CFPM: 63%, CZOP: 59%, MEPM: 61%, IPM: 69% (P=0.52)). The three antibiotics investigated in this trial were as effective as the reference agent, CFPM, in both the intention-to-treat and per-protocol populations. In both the intention-to-treat and per protocol analyses, success rates of the initial therapy at days 3 to 5 were not significantly different among four drugs [CFPM: 52 and 54%, CZOP: 46 and 47%, MEPM: 54 and 55%, IPM: 49 and 53% (P=0.70 and 0.68, respectively)]. Conclusions: CZOP, MEPM, and IPM were as effective as CFPM for adult FN patients with hematological malignancies and solid tumors as an empiric therapy. Disclosures: Tamura: Kyowa Hakko Kirin Co., Ltd,: Consultancy.

Abstract 3759 Imatinib treatment dramatically improves survival in chronic myeloid leukemia (CML) patients, but whether its effects of imatinib can be considered a cure remains controversial. This is because primitive, quiescent, Philadelphia-positive stem cells from patients with CML are insensitive to imatinib in vitro. Nonetheless, it was recently recognized that some patients with a complete molecular response (CMR) could sustain that response after discontinuation of imatinib. In a non-randomized prospective study, Mahon et al. reported that among patients with CMR lasting at least 2 years, CMR was sustained in 41% after discontinuation of imatinib. To characterize the clinical outcomes and profiles of chronic phase CML patients who discontinued imatinib, we conducted a nationwide survey in Japan. Among 3,242 imatinib-treated CML patients, 50 (1.5%) were identified who discontinued imatinib therapy for at least 6 months; of those, 43 were analyzed further. Molecular recurrence was detected in 19 patients, and the complete molecular response (CMR) rate was estimated to be 47% following imatinib discontinuation. Notably, the durations of imatinib therapy and CMR before cessation of therapy were significantly longer, and imatinib dose intensity and the frequency of prior IFN-a administration were significantly higher, in patients sustaining CMR for 12 months after cessation than in those with molecular recurrence. No significant correlations were detected between molecular recurrence and age, sex, Sokal risk, imatinib daily dose, combination with IFN-a, or time to achieve CMR. Moreover, we found a significant difference in estimated CMR rate following discontinuation between patients who had sustained CMR for greater than 24 months prior to imatinib discontinuation and those with less than 24 months (78% vs. 15%, p =0.0002 by Log-rank test, Figure). Based on multivariate regression analysis, only imatinib dose intensity and prior IFN-a administration were independently predictive of molecular recurrence within 12 months (p =0.0035, p =0.0060). The identified prediction formula was: Y= −0.0061 x dose intensity of imatinib(g)-3.17171 x prior IFN-a(Yes=1/No=0) +4.0124. If 1/(1+exp(-1 × Y)) > 0.5, molecular recurrence was predicted; the total accuracy rate of the formula was 82.5%. Although the depth of the molecular response should be a factor influencing long-term sustained CMR after discontinuation of imatinib, other factors, for example an immunological mechanism modified by IFN-a, might control quiescent CML stem cells. To increase the “cure” rate among CML patients, it will be necessary to establish a treatment strategy on the basis of large prospective study of imatinib discontinuation. This should entail the use of a highly sensitive and strict method for monitoring minimal residual disease over the course of a long follow-up period. Disclosures: No relevant conflicts of interest to declare.

A case of extramedullary plasmacytoma presenting with biclonal gammopathy is reported. The patient was an 82-year-old man in whom monoclonal-protein (M-protein) was not noted during his first hospitalization. On his second hospitalization generalized lymph node swelling and biclonal gammopathy (IgG-k, IgA-k) were observed. Histological findings were compatible with those of extramedullary plasmacytoma. In the terminal stages, the patient became cachexic. The autopsy disclosed dissemination of the plasmacytoma. Only two other cases have been reported in the literature, and a review of these previous reports is included.(Internal Medicine 32: 412-415, 1993)

A 66-year-old Japanese male with diffuse non-Hodgkin's lymphoma, of the pleomorphic type, complicated with Klinefelter's syndrome is reported. His phisique was characterized by a long arm span, disproportionately longer lower body dimensions and a small sized penis. He had no children. Chromosomal study revealed 47, XXY and hormonal quantification showed hypergonadtropic hypogonadism. Although chemotherapy was administered, his disease took a progressive course and he died. A discussion of chromosomal alteration and oncogenesis and review of the literature are included.(Internal Medicine 31 : 496-499, 1992)

[Background] We report the results of a prospective multi-institutional clinical trial of BMT from an HLA-matched URD following RIC. [Patients and Methods] The conditioning regimen included cladribine 0.11 mg/kg on day -8 to day -3, busulfan 4 mg/kg po on day -6 and day -5, and 4 Gy TBI on day -1. GVHD prophylaxis included cyclosporine and short-term methotrexate. Patients with hematologic diseases were eligible for this study if they were either older than 50 years or had significant medical contraindications to undergo conventional transplantation. Primary endpoints were neutrophil engraftment and achievement of complete donor-type chimerism (CD3+ cells >90%) on day 90. Regimen-related toxicities (RRT) between day -8 and day 28 were assessed by the NCI-CTC v2.0. A total of 27 patients were registered, but one patient was removed before transplant because of severe fungal infection. [Results] The median follow-up time was 722 days (range, 324–996) among survivors. The median age of patients was 56.5 years (36–64). Nine of the 26 patients (36%) had advanced-stage diseases and 3 (11%) had failed previous high-dose autologous or allogeneic transplantation. The diagnoses included AML (n=9), MDS/MPD (n=7), NHL (n=3), ALL (n=2), CML, ATLL, PCL, biphenotypic acute leukemia, and severe aplastic anemia (n=1). The median number of infused nucleated cells was 2.2 × 108/kg. After transplant, while one patient experienced engraftment failure and subsequent sepsis, and died on day 34, the remaining 25 patients achieved neutrophil engraftment (median, 17th day). Another patient was censored from the study due to grade 4 liver dysfunction, which developed on day 19, which left 24 patients for the chimerism analysis. The percentage of donor chimerism in CD3+ cells on days 28, 56 and 90 was, respectively, 88% (21/24), 100% (24/24) and 100% (24/24). Grade 3 RRT included arrhythmia (n=1), hypoxia (n=3), hyperbilirubinemia or hypertransaminasemia (n=7), stomatitis (n=18) and diarrhea (n=4), and grade 4 RRT included hypoxia (n=1) and hyperbilirubinemia (n=1). Acute GVHD of grade II, III and IV occurred in 27%, 27% and 4%, respectively. Ten of 15 evaluable patients (67%) had extensive chronic GVHD. CMV reactivation occurred in 23 patients (89%); 4 had histologically confirmed CMV colitis, 1 had CMV pneumonitis and 1 had CMV hepatitis, while the remaining patients had asymptomatic viremia. Of the 16 patients with measurable disease at the time of BMT, 15 achieved complete remission. The 100-day and 1-year cumulative incidences of non-relapse mortality (NRM) estimated by the Kaplan-Meier method were 20% and 54%, respectively. The cause of death that contributed to NRM was infection, with grade 0–I acute GVHD in 29% and grade II–IV acute GVHD in 71%. The 100-day and 1-year cumulative incidences of relapse were 8% and 35%, respectively, and the 1-year overall and progression-free survival rates were 42% and 30%, respectively. [Conclusions] The results support the feasibility of this procedure with a high response rate, but there is still a problem with the high NRM due to uncontrollable infections primarily associated with GVHD.

Background: Approximately 70–80% of all newly diagnosed patients with adult AML achieve a complete remission (CR). However, only about one third of those pts remain free of disease for more than 5 years. It is therefore important to predict which pts are most likely to suffer a relapse and thus perform alternative treatments such as stem cell transplantation in order to improve the prognosis of AML. We evaluated the impact of the detection of Wilms’ tumor gene1 (WT1) mRNA in the peripheral blood on the prognosis of AML pts. Patients and Methods: From June 1, 2001 to October 30, 2003 a study was performed on 191 pts with AML which evaluated the clinical usefulness of a WT1 mRNA assay kit for the early detection of relapse in AML pts (submitted in Rinsho Ketsueki). From these 191 pts, we selected the subjects for this study. All selected subjects achieved a complete remission, and also had their WT1 expression analyzed after consolidation therapy. The pts were excluded if they had received a stem cell transplantation before relapse. The WT1 mRNA levels were determined using the WT1 mRNA assay kit (Otsuka Pharmaceutical Co. Ltd) in accordance with the standard operating procedures using peripheral blood. The lower limit of detection was 50 copy/μgRNA. Therefore, less than 50 copy/μgRNA was judged as negative. All induction, consolidation and maintenance therapies were performed according to institutional standards. Results: Of 118 pts who achieved a complete remission, 50 pts (median age: 56 yrs 22–86) were evaluable. Their median WT1 mRNA levels before induction therapy was 48327 copy/μgRNA (137–329185). The WT1 mRNA levels at diagnosis did not correlate with either the relapse rate, DFS or OS, respectively. After CR, the WT1 mRNA level ranged from Conclusion: This study shows that the detection of the WT1 mRNA in the peripheral blood after treatment closely correlated with the prognosis in AML.

A case of chronic leukemia is reported. Malignant cells had the morphology of lymphocytes and an affinity for skin. Cytochemically, they were peroxidase negative, and NaF-resistant alpha-naphthyl esterase positive. The peripheral mononuclear cells formed E-rosettes and reacted with Leu 1 and OKM1. They were unreactive with OKT3, OKT4, OKT6, OKT8, and OKIa1. The cells did not possess surface IG, C3b receptors, or IgG Fc receptors (EAIgG). They responded weakly to phytohemagglutinin, and did not respond to concanavalin A. The cells did not adhere to Petri dishes or phagocytose latex beads. It is concluded that it was a case of OKT3-, OKM1+, EAIgG- T-cell chronic lymphocytic leukemia. This suggests that OKT3 does not recognize all peripheral T-cells, and that OKM1 is not specific for the monocyte-myeloid lineage. These cells may be useful in the characterization of E+, OKM1+ subset of peripheral mononuclear cells.

After a 3-month leukopenic phase, a patient developed hematologic pictures of acute promyelocytic leukemia (APL). Treatment with chemotherapy and radiotherapy had been given 10 months previously for a non-Hodgkin's lymphoma (NHL) of diffuse large cell type arising in the Waldeyer's ring. A computed tomographic scan demonstrated a high density mass in the left frontal cerebrum, which was enhanced uniformly by the contrast material. Cytocentrifuge examination of cerebrospinal fluid also showed an excess of promyelocytes. From these observations, the mass was considered to be an infiltration of leukemic cells. The intracerebral mass and meningeal involvement were resolved concomitantly with a hematologic remission of APL after intrathecal injection of cytosine arabinoside and systemic combination chemotherapy. This is a particular case of APL previously undescribed, representing an unusual presentation with intracerebral APL mass as well as a rare posttherapeutic APL following NHL. Cancer 59:94–98, 1987.

The morphologic features, phenotype, and functions of OKM1+ leukemic T-cells were studied. The leukemic T-cells in two patients with chronic lymphocytic leukemia (CLL) had specific features of large granular lymphocytes (LGL), and those in two patients with acute lymphocytic leukemia (ALL) had L2 morphologic characteristics. The phenotype of the leukemic cells from one patient with CLL was OKM1+, ER+, OKT3+, OKT4+, OKT8-, OKIa1-, IgGFc receptor (EA gamma)+, Leu-7+, Leu-11b+, and anti-Tac-. The cells had antibody-dependent cell-mediated cytotoxicity (ADCC), but no natural killer (NK) activity. They had a definitive helper effect on pokeweed mitogen-induced normal B-cell differentiation. The leukemic cells from the other patient with CLL were Leu-7-, and Leu-11b-, and lacked both ADCC and NK activity. The leukemic cells in the two patients with ALL were ER+, OKM1+, Leu-7-, and Leu-11-, and did not have any cytotoxicity. One was EA gamma +, and the other was EA gamma -. These findings suggest that OKM1+ leukemic T-cells consist of at least two subgroups: (1) T-cells with the morphologic features of LGL; and (2) those with a lymphoblastic morphologic type. In either case, the phenotype is novel and suggests the emergence of a small, distinct lymphocyte subset.

A case of malignant lymphoma with a helper activity of neoplastic cells is reported. On admission, a significant number of plasma cells of polyclonal nature were seen in the peripheral blood, and polyclonal hypergammaglobulinemia was seen. The biopsied lymph node showed poorly differentiated lymphocytic lymphoma with marked proliferation of plasma cells. At the terminal stage, the patient became leukemic in contrast with the disappearance of plasma cells from the peripheral blood. Although the leukemic cells failed to form sheep erythrocyte rosettes, they were considered to be of T-cell origin morphologically. Cytochemically, they had a "dot"-like pattern of alpha-naphthyl acetate esterase and acid phosphatase activity. Ultrastructurally, they had highly convoluted nuclei, and cytoplasmic clustered dense bodies. They showed marked helper activity on pokeweed mitogen-induced B-cell differentiation in vitro. This case may provide a novel view concerning the cause of hypergammaglobulinemia induced by lymphoproliferative disorders.