Low-grade B-cell Lymphoproliferative Disorder Research Articles

An overview of prognostic markers in patients with CLL.

Chronic lymphocytic leukemia (CLL) is a low-grade B-cell lymphoproliferative disorder. It is the most prevalent type of leukemia in the western countries, with a median age at diagnosis of 70 years. In 2023, it is estimated that there will be 18,740 new cases of CLL, and an estimated 4,490 people will die of this disease. It represents 1.0% of all new cancer cases in the U.S. The rate of new cases was 4.6 per 100,000 men and women per year based on 2016-2020 cases, age-adjusted. Death rates from CLL are higher among older adults, or those 75 and older. The death rate was 1.1 per 100,000 men and women per year based on 2016-2020 deaths, age-adjusted. A common question that patients with CLL ask during their first clinic visit is: "How long will it be before I would need treatment?" Although this might seem like a simple question, the answer is not straight forward. CLL is a heterogenous disease, with a variable clinical course. Some patients may present with an aggressive disease requiring early initiation of treatment, while others have an indolent course and some, having so called smoldering CLL, may never need treatment. The variability in disease course can make predicting disease prognosis a complicated process. This brings forth the importance of establishing prognostic models that can predict disease course, time to treatment, and survival outcomes in such a heterogenous disease. The Rai and Binet staging systems were developed in the late 1970s to early 1980s. They separated patients into different stages based on clinical characteristics and laboratory findings. These simple staging systems are still in use; however, several prognostic markers need to be added for an individualized assessment and, with the recent development of genomic techniques leading to better understanding of CLL at the molecular level, newer prognostic markers have emerged.

CD5-Negative, CD10-Negative Low-Grade B-Cell Lymphoproliferative Disorders of the Spleen.

CD5-negative, CD10-negative low-grade B-cell lymphoproliferative disorders (CD5-CD10-LPD) of the spleen comprise a fascinating group of indolent, neoplastic, mature B-cell proliferations that are essential to accurately identify but can be difficult to diagnose. They comprise the majority of B-cell LPDs primary to the spleen, commonly presenting with splenomegaly and co-involvement of peripheral blood and bone marrow, but with little to no involvement of lymph nodes. Splenic marginal zone lymphoma is one of the prototypical, best studied, and most frequently encountered CD5-CD10-LPD of the spleen and typically involves white pulp. In contrast, hairy cell leukemia, another well-studied CD5-CD10-LPD of the spleen, involves red pulp, as do the two less common entities comprising so-called splenic B-cell lymphoma/leukemia unclassifiable: splenic diffuse red pulp small B-cell lymphoma and hairy cell leukemia variant. Although not always encountered in the spleen, lymphoplasmacytic lymphoma, a B-cell lymphoproliferative disorder consisting of a dual population of both clonal B-cells and plasma cells and the frequent presence of the MYD88 L265P mutation, is another CD5-CD10-LPD that can be seen in the spleen. Distinction of these different entities is possible through careful evaluation of morphologic, immunophenotypic, cytogenetic, and molecular features, as well as peripheral blood and bone marrow specimens. A firm understanding of this group of low-grade B-cell lymphoproliferative disorders is necessary for accurate diagnosis leading to optimal patient management.

Modeling Lymphoplasmacytic Lymphoma/Waldenström Macroglobulinemia in Transgenic Mice Using Human MYD88L256P Mutated Protein

Lymphoplasmacytic lymphoma (LPL)/Waldenström macroglobulinemia (WM) is a B-cell disorder resulting from the accumulation of cloncal lymphoplasmacytic cells in the bone marrow (BM) along with excessive secretion of immunoglobulin M paraprotein. Despite recent advances in treatment LPL/WM remains incurable. Generating a refined LPL/WM mouse model that would facilitate studying this disease as well as enable stringent in vivo validation of potential therapeutic approaches has been a long-sought goal for the filed. Interestingly, among the most common mutations identified by recent high-throughput studies there was a single gain of function point mutation in the MYD88 gene, with a predicted non-synonymous amino acid (L265P) change, found in over 91% of patients. Therefore, we hypothesized that generation of transgenic mice overexpressing MYD88L256Pcould recapitulate the human setting of LPL/WM.To overcome problems inherently related to embryonic lethality, we generated MYD88WT and MYD88L256P conditional transgenic mice expressing human proteins. To remove a transcriptional stop cassette and activate MYD88 expression in vivo, we mated the conditional mice with mice expressing Cre recombinase under the control of Activation-Induced Cytidine Deaminase (AID) gene promoter to generate AIDCre/-;MYD88WT/- and AIDCre/-;MYD88L256P/- double-mutant mice. Recombinase activity driven by the AID gene promoter caused removal of the stop cassette and expression of MYD88 in germinal center (GC) and post-GC B cells, the appropriate B-cell compartment from which LPL/WM clones are thought to originate in humans. Young (up to 30 weeks of age) AIDCre/-;MYD88WT/- and AIDCre/-;MYD88L256P/- mice where indistinguishable from AIDCre/- mice as assessed by external physical examination. Moreover, obvious histologic and IHC differences in spleens, lymph nodes, and bone marrows between the mutant genotypes and the AIDCre/- control mice were not found. No clonal bands for the IgH gene, nor M-spikes were detected in Southern blots and serum protein electrophoresis, respectively. However, after 30 weeks of age, and at variable times thereafter, some of the AIDCre/-; MYD88L256P/- aging cohort (n=27) mice developed skin rash and excoriation as well as loss of hair in the submandibular areas. A fraction of AIDCre/-; MYD88L256P/- animals that weren't sacrificed because of the severe dermatitis had enlarged lymph nodes and appeared sick. To assess whether MYD88 transgenic mice develop B-cell lymphomas or major pathologic alterations consistent with the diagnosis of LPL/WM, animals were euthanized at different ages and lymphoid organs were rigorously examined. In spleens and lymph nodes of 8 of the AIDCre/-; MYD88L256P/- animals, a nodular lymphoid infiltrate composed predominantly of small atypical cells varyingly infiltrated with CD138+ plasma cells was observed. Lymphoid cells infiltrated other organs including the BM. Enhanced expression of MYD88 and activation of NF-κB activity within atypical lymphoid nodules in diseased transgenic mice was documented by IHC staining for MYD88 and p65. However, no clonal bands of the IgH gene were detected in Southern blots, suggesting that overexpression of MYD88L256P/- mutant protein in activated B-cells gave rise to a polyclonal lymphoproliferative disorder. Consistently, serum protein electrophoresis analysis showed diffuse, polyclonal increase in γ-globulins. Moreover, stains of peripheral blood smears revealed rouleaux formation suggesting increased concentrations of plasma proteins. In addition, one of AIDCre/-; MYD88L256P/- animals developed a more aggressive monoclonal disease resembling human diffuse large B-cell lymphoma. However, large atypical lymphoid cells in this mouse lacked expression of MYD88 and nuclear p65. All AIDCre/- controls and AIDCre/-; MYD88WT/- mice lacked described phenotypes and were histologically unremarkable.Taken together, these results demonstrate that although MYD88L256P/- alone might not be sufficient to induce a malignant transformation in the mature B-cell compartment, it gave rise to a low-grade mature non-clonal B-cell lymphoproliferative disorder with some of the characteristic futures of LPL/WM. Therefore, the MYD88L256P/- mutation might be necessary but not sufficient for LPL/WM development and must be present with concomitant “second hit” genetic alterations for a neoplasm to develop. DisclosuresTreon:Pharmacyclics: Consultancy, Research Funding.

2-[18F]-FDG PET/CT Role in Detecting Richter Transformation of Chronic Lymphocytic Leukemia and Predicting Overall Survival

IntroductionChronic lymphocytic leukemia (CLL) is an indolent, low-grade B-cell lymphoproliferative disorder, which may evolve into aggressive lymphoma, a phenomenon called Richter syndrome (RS). Our aim was to study the accuracy of 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/computed tomography (2-[18F]-FDG PET/CT) and its semiquantitative parameters for the detection of RS and the impact on overall survival (OS). Materials and MethodsEighty patients with histologically proven CLL were retrospectively included. PET/CT images were qualitatively and semiquantitatively examined by estimating the maximum standardized uptake value body weight (SUVbw), lean body mass (SUVlbm), body surface area (SUVbsa), lesion-to-blood-pool SUV ratio (L-BP SUV R), lesion-to-liver SUV ratio (L-L SUV R), total lesion glycolysis (TLG), and metabolic tumor volume (MTV) and comparing them with the main clinical-histologic variables. OS curves were plotted according to the Kaplan-Meier method. ResultsSeventy-eight patients had positive 2-[18F]-FDG PET/CT, whereas the remaining 2 were not FDG-avid. All PET/CT metabolic parameters were significantly higher in the RS group compared with the no-RS group, except for MTV and TLG. The best thresholds identified were 9 for SUVbw, 5.3 for SUVlbm, 1.7 for SUVbsa, 2 for L-L SUV R, and 4.8 for L-BP SUV R. After a median follow-up of 32 months, 24 patients died; OS was significantly shorter in patients with RS than patients without RS (16.5 vs. 27.8 months; P = .001). Binet-stage, B symptoms, SUVbw, SUVlbm, SUVbsa, L-L SUV R, and L-BP SUV R were shown to be independent prognostic features. ConclusionsSemiquantitative PET/CT parameters that are SUV-related may be useful in discriminating patients with a high risk of developing RS and also for predicting OS.

Human MYD88L265P is insufficient by itself to drive neoplastic transformation in mature mouse B cells

AbstractMYD88L265P is the most common mutation in lymphoplasmacytic lymphoma/Waldenström macroglobulinemia (LPL/WM) and one of the most frequent in poor-prognosis subtypes of diffuse large B-cell lymphoma (DLBCL). Although inhibition of the mutated MYD88 pathway has an adverse impact on LPL/WM and DLBCL cell survival, its role in lymphoma initiation remains to be clarified. We show that in mice, human MYD88L265P promotes development of a non-clonal, low-grade B-cell lymphoproliferative disorder with several clinicopathologic features that resemble human LPL/WM, including expansion of lymphoplasmacytoid cells, increased serum immunoglobulin M (IgM) concentration, rouleaux formation, increased number of mast cells in the bone marrow, and proinflammatory signaling that progresses sporadically to clonal, high-grade DLBCL. Murine findings regarding differences in the pattern of MYD88 staining and immune infiltrates in the bone marrows of MYD88 wild-type (MYD88WT) and MYD88L265P mice are recapitulated in the human setting, which provides insight into LPL/WM pathogenesis. Furthermore, histologic transformation to DLBCL is associated with acquisition of secondary genetic lesions frequently seen in de novo human DLBCL as well as LPL/WM-transformed cases. These findings indicate that, although the MYD88L265P mutation might be indispensable for the LPL/WM phenotype, it is insufficient by itself to drive malignant transformation in B cells and relies on other, potentially targetable cooperating genetic events for full development of lymphoma.

Cases of acquired C1 inhibitor deficiency treated with rituximab

CASE 1 A 48-year-old woman developed sudden onset of abdominal pain with repetitive vomiting in March 2013. Symptoms spontaneously resolved over 5 days. Similar unpredictable attacks recurred along with episodes of asymmetric, nonpitting swelling of the extremities and genitalia. Antihistamines and prednisone administered during multiple emergency department (ED) visits were ineffective. In February 2014, she sought care in an ED for severe facial swelling, and a C4 level was found to be low. Consultation with allergy was requested. Her family history for angioedema was negative. She had no exposure to exogenous estrogen or angiotensin converting enzyme inhibitors and denied prior medical problems. Diagnostic studies revealed low C4, C1q, and C1 inhibitor (C1INH) antigenic level with undetectable C1INH functional activity. A diagnosis of ACID was established and she was referred to oncology for additional investigation. She was prescribed icatibant, which was effective in arresting attack progression. After the diagnosis, she had an accelerated course of attack frequency and severity requiring approximately 21 icatibant injections monthly during May and June of 2014. Attacks persisted on a weekly basis culminating in a laryngeal attack in August 2014. Diagnostic evaluation revealed a low-grade B-cell lymphoproliferative disorder for which rituximab was recommended. She completed her 4-dose course of rituximab in October 2014, and since then has essentially been symptom free with over 1-year follow-up.

A Case of Intestinal T Cell Lymphoma Presenting With Gastrointestinal Bleeding

Intestinal non-Hodgkin's T-cell lymphoma (NHTCL) is a rare, extranodal manifestation of lymphoma. We report a case of a 67 year old man with a history of dyslipidemia, drug-induced neutropenia and low grade B-cell lymphoproliferative disorder (most consistent with B cell chronic lymphocytic leukemia) who presented with a two week history of melena and abdominal pain. An EGD was performed and did not reveal a bleeding source. The patient continued to have dark stool, hematochezia and progressive anemia, thus a colonoscopy was performed. Multiple 5mm ulcers were noted in the cecum, ascending and transverse colon on colonoscopy. Biopsies revealed an aggressive NHTCL. Cytology showed strong expression of CD2 and CD3 with absent expression of CD5, CD7, CD34 and TdT. An aggressive proliferation index of 75-80% was noted.Figure 1Figure 2Figure 3FDG-PET scan of the abdomen/pelvis revealed multiple foci of increased metabolic activity located in the abdomen, particularly associated with small bowel loops and mesenteric lymph nodes. A bone marrow biopsy was obtained and displayed kappa restricted CD5 coexpression consistent with history of small B-cell lymphoma. Bone marrow showed no immunohistochemical evidence of NHTCL, confirming the diagnosis of primary intestinal lymphoma in accordance with Dawson criteria.1 The patient was evaluated by oncology services at two separate centers, and it was agreed that the patient had primary NHTCL. He was placed on a clinical trial of CHOP-Belinostat. Three months after diagnosis, the patient developed severe, acute abdominal pain and was found to have bowel perforation. Laparotomy revealed extensive tumors in the small bowel, of which several had perforated. His clinical course was complicated and after a prolonged ICU stay, he was transitioned to comfort measures only and died shortly thereafter. Primary gastrointestinal (GI) lymphoma is rare, comprising 1-4% of all GI malignancies, of which less than 10% are of T-cell origin.1 We suspect this patient had Enteropathy Associated T Cell Lymphoma (EATL). Patients with EATL typically present at age 60 with lesions predominantly affecting the small bowel (especially jejunum), and less frequently the colon and stomach.1,2 There is a strong association with celiac disease, seen in at least one third of patients diagnosed with EATL.2 This patient had no known history of celiac disease and no villous atrophy was seen on EGD. EATL is aggressive and carries a poor prognosis, optimal treatment is not known.3

Hairy cell leukemia - immunotargets and therapies.

Hairy cell leukemia (HCL) is an indolent low-grade B-cell lymphoproliferative disorder that is reasonably sensitive to standard first-line purine analog therapy. However, in many cases, repeat relapses occur, requiring multiple courses of purine analog therapy, promoting eventual drug resistance. This, coupled with the concerning side effects of repeated purine analog exposure, has prompted the search for alternative targets and therapies that may provide deeper remissions. Novel strategies employing immune-mediated targeting via monoclonal antibody therapies and recombinant immunotoxins appear promising in HCL and are currently under investigation. More recently, the concept of targeted kinase inhibition using small-molecule inhibitors in HCL has emerged as another potentially viable option. As a deeper understanding of the aberrant molecular pathways contributing to the pathogenesis of HCL develops, the landscape of management for HCL, particularly in the relapse setting, may change significantly in the future as a result of these promising immunotargets and therapies.

Plasmablastic transformation of low-grade CD5+ B-cell lymphoproliferative disorder with MYC gene rearrangements

Plasmablastic transformation of low-grade B-cell lymphoproliferative disorders is rarely reported, particularly in cases with clonal evolution. Moreover, the relationship of these 2 morphologically and immunophenotypically distinctive neoplasms remains elusive. Here, we report 2 exceptional cases of plasmablastic transformation with apparently direct transformation from their preceding low-grade B-cell lymphoproliferative disorder. In both cases, the plasmablastic transformation and low-grade lymphoproliferative disorder shared the same immunoglobulin heavy chain gene rearrangements and an identical chromosomal translocation. Notably, both plasmablastic transformation cases also carried MYC gene rearrangements on chromosome 8q24, which have been frequently identified in de novo plasmablastic lymphoma. Therefore, our data suggest that dysregulation of MYC gene may play a critical role in the pathogenesis of plasmablastic transformation.

A Phase I Dose-Finding Trial of Recombinant Interleukin-21 and Rituximab in Relapsed and Refractory Low Grade B-cell Lymphoproliferative Disorders

We conducted a phase I study to determine the safety, maximum-tolerated dose (MTD), and efficacy of weekly bolus recombinant human interleukin-21 (rIL-21) plus rituximab in patients with indolent B-cell malignancies. One week after a lead-in rituximab dose, cohorts of three patients were treated with 30, 100, or 150 μg/kg rIL-21 weekly for four weeks, concurrent with four weekly doses of rituximab. Patients with stable disease or better were eligible for a second course of therapy. Twenty-one patients with relapsed small lymphocytic lymphoma/chronic lymphocytic leukemia (SLL/CLL, n = 11), follicular lymphoma (n = 9), or marginal zone lymphoma (n = 1) were enrolled, with 19 completing at least one course of therapy. The MTD for rIL-21 was 100 μg/kg, based on observed toxicities including nausea, vomiting, diarrhea, hypotension, edema, and hypophosphatemia. Clinical responses were seen in 8 of 19 evaluable patients (42%; 3 CR/CRu, 5 PR), with 4 of longer duration than the patient's previous response to rituximab-based treatment (median 9 months vs. 3 months). Outpatient therapy of indolent B-cell malignancies with rituximab and weekly rIL-21 was well tolerated and clinically active, with durable complete remissions in a small subset of patients. Additional studies of rIL-21 and anti-CD20 antibodies in lymphoma and SLL/CLL are warranted.

The bone marrow microenvironment in Waldenstrom macroglobulinemia

Waldenstrom macroglobulinemia (WM) is a low-grade B-cell lymphoproliferative disorder characterized primarily by specific homing and growth of tumor cells within the bone marrow niches. The progressive growth of tumor cells throughout the bone marrow indicates that the tumor cells are capable of homing and adhering to specific niches that allow growth, survival and drug resistance. In this review we highlight the interaction of the tumor cells in WM and the bone marrow microenvironment including bone marrow stromal cells, endothelial cells and mast cells. Migration, adhesion and downstream activation of signaling pathways leads to cell trafficking and cell dissemination in WM. Future therapeutic agents need to target not only the tumor clone, but also its close interaction with the bone marrow microenvironment.

Absence of Mutations of the Histone Methyltransferase Gene EZH2 In Splenic B-Cell Marginal Zone Lymphoma

AbstractAbstract 5086 BackgroundSplenic marginal zone lymphoma (SMZL) is a rare low-grade B-cell lymphoproliferative disorder with characteristic clinical, cytological, histological and immunophenotypical features. The most common cytogenetic abnormality, present in 30–40% of the patients is the 7q deletion, that extends from 7q21 to 7q36. This aberration may represent a primary pathogenic event in SMZL. Recently, mutations in the EZH2 gene, located at 7q36.1, have been described in different hematological malignancies including B-cell lymphomas. However, the role of the EZH2 gene in SMZL has to be elucidated. AimTo determine the prevalence of EZH2 mutations in a cohort of SMZL patients. Patients and MethodsTwenty-nine patients with SMZL were screened for mutations in the EZH2 gene. From the whole cohort, 11 patients presented 7q deletion (three of them as a single anomaly), 11 had a normal karyotype and 7 had other cytogenetic aberrations. The mutational analysis of the EZH2 gene was performed by direct sequencing using primers covering the whole exome of the gene. DNA was extracted from CD19 isolated B-cells from peripheral blood or from total lymphocytes if the percentage of pathologic B-cell was higher than 50%. ResultsFrom the whole cohort of 29 SMZL patients, no pathogenic mutations (frameshift or nonsense mutations) were detected in the EZH2 gene in any of the patients analyzed. Five patients harboured the missense mutation D185H in exon 6, that has been previously described as a single nucleotide polymorphism (SNP). ConclusionsIn conclusion, the EZH2 gene is not mutated in our series of SMZL patients suggesting that this gene is not involved in the pathogeny of this entity. Acknowledgments:Fellowship FI2008 (AGAUR) to LMA, This work was supported (in part) by grants from Instituto de Salud Carlos III FEDER; Red Temática de Investigación Cooperativa en Cáncer (RTICC, FEDER): RD06/0020/0031 and RD07/0020/2004; Ministerio de Sanidad y Consumo (Spain): PI07/0586. Disclosures:No relevant conflicts of interest to declare.

Skin spicules: A newly described paraneoplastic phenomenon associated with a marginal zone B-cell lymphoma

Paraneoplastic signs are an important clue to diagnosing an associated malignancy. We report an unusual variant of the sign of Leser-Trélat in a patient with a low-grade B-cell lymphoproliferative disorder and intertriginous skin spicules with histologic morphology of minute seborrheic keratoses.

Incidence of Disease Transformation and Development of MDS/AML in 165 Patients with Waldenström's Macroglobulinemia (WM) Treated with Fludarabine (F)-Based Regimen in Three Studies (French Cooperative Group on CLL/WM)

Nucleoside analogs (NA) are used alone or in combination in low grade B-cell lymphoproliferative disorders for 20 years. The incidence of disease transformation (Richter syndrome: RS) and development of MDS/AML among patients (pts) with indolent B-cell malignancies receiving NA are still controversial. We have reviewed the crude incidence of RS and MDS/AML in 165 WM patients treated with 3 F-based regimens.Results: Retrospective Study 1 (Leblond J Clin Oncol 1998): F (25mg/m2 iv D1–5) in 71 WM pts in relapse/refractory treated with alkylator, median time from diagnosis (dg) to tt: 5.9yrs, median prior tt: 2 (1–4). Randomized prospective study 2 (Leblond Blood 2001) in 92pts in first relapse after alkylator: Arm 1: F (25mg/m2 ivD1–D5) (45pts) vs Arm 2: CAP (doxorubicine 25mg/m2 IV D1, cyclophosphamide 750mg/m2 IV D1, Prednisone 40mg/m2 D1–5) (45pts), median time from dg to tt: 3.9yrs. Retrospective study N°3 (Tamburini Leukemia 2005) in first-line WM (14pts) or relapse WM (35pts): F 30mg/m2 D1–3 by oral route + Cyclophosphamide (C) 300mg/m2 D1–3 by oral route, median time from dg to tt: 2.1 yrs. The incidences of MDS/AML and RS are shown in Table 1 Discussion: the crude incidence of RS varied from 6,6% to 8% and was not statistically different in the randomized prospective study N°2 between the two groups. However, the incidence reported in pts treated with only alkylating-based regimens was lower: 3/167(1.8%) (Facon J Clin Oncol1993) and 3/217 (1.4%) (Garcia Sanz Br J Hematol 2001) and could be explained by a F use as salvage treatment in the CAP arm. The impact of fludarabine on RS needs to be confirmed in larger prospective studies. The crude incidence of MDS/AML varied from 1.4 to 8.9% in pts treated with fludarabine alone and was 6% in pts treated with F+C. The incidence reported in pts treated with alkylating based regimens varied from 1% (2/167, Facon 1993, 3/217 Garcia-Sanz 2001) to 6% (3/46, Kyle Br J Hematol 2000,) and was not different. In other low grade B-cell malignancies, a higher incidence of MDS/AML has been reported in pts treated with analog-alkylator combination compared to F or alkylator alone (Morrison J Clin Oncol 2002, Bowcock Br J Hematol 2006, Tam Hematologica 2006). In our study, the rate was the same in the two populations. The impact of late effects, particularly second malignancies, need to be better evaluated in prospective studies, especially in young patients and clinicians should discuss the risk when recommending such therapy to pts.MDS/AML and RS incidences in the three studiesStudy N°, ptsMedian survival time from studyMedian follow-up time from studyMDS/AML (N,%)RS (N,%)N°1 71 pts23 mo34 mo1/71 (1.4%)5/71 (7%)N°2- 92 pts41mo( arm1), 45 mo (arm2)34mo4/45 (8.9%, arm1), 2/45( 4.5%, arm2)3/45 (6.6% arm1), 2/45 (4.5%, arm2)N°3-49pts64% at 60 mo42 mo3/49 (6%)4/49 (8%)

Outcome of Sibling Reduced-Intensity Conditioning Allogeneic Stem Cell Transplantations in Low-Grade B Cell Lymphoproliferative Disorders. A Single Centre Experience.

Reduced intensity conditioning allogeneic stem cell transplantations (allo-SCT) have been developed to exploit graft-versus-malignancy effect while reducing the toxicity of allo-SCT. We report the outcome of 21 patients with low-grade B cell lymphoproliferative disorders transplanted in a single center. The mean age of the patients was 54 years (range 32–66) with 11 males, 10 females. Follicular lymphoma was the diagnosis in 10 patients, CLL in 5, mantle cell lymphoma in 4, MALT lymphoma in 1 and lymphoplasmocytoid lymphoma in 1 patient. The median number of prior treatment lines was 2. All patients received peripheral blood stem cell transplants from sibling donors and no patients had undergone a prior autologous SCT. 12/21 patients (57%) received a ATG based conditioning regimen while the remainder, 9/21 (42%) received a Campath containing conditioning regimen. Full donor chimerism was confirmed in 17/19 (89%) patients. Acute graft versus host disease (GVHD) developed in 5/21 (23%) of the patients. Chronic GVHD occurred in 7/21 (33%) with 5/21 occuring post donor lymphocyte infusion (DLI). DLI has been administered in 11/21 patients (52%), 2 for progressive disease and 9 for re-emerging mixed chimerism. Non-relapse mortality (NRM) at 100 days and 1 year were 5% and 12.5% respectively. With a median follow up of 21 months (range 3–54) the overall survival rates (OS) at 1 year and 2 years were 72% and 58% respectively. Progression free survival (PFS) at 1 year and 2 years were 66% and 50%. We have shown that reduced intensity conditioning allogeneic stem cell transplantation is associated with a low TRM comparible to that of autologous transplantation and allows long term control of low grade B-cell lymphoproliferative disorders.

Trisomy 12 in a case of multiple cutaneous squamous cell carcinoma in association with chronic lymphocytic leukemia

Chronic lymphocytic leukaemia (CLL), which shares clinical and morphological overlap with small lymphocytic lyjmphoma (SLL), is a low-grade clonal B-cell lymphoproliferative disorder that accounts for 25% of all cases of leukaemia in Western countries, while it is considered rare in Oriental patients and is thought to constitute only 2% of all leukemias in these patients.[1] CLL is associated with an increased incidence of secondary malignant neoplasms, such as brain tumors, melanomas, and gastrointestinal-tract carcinomas[2]. However, the simulataneous occurrence of CLL and cutaneous squamous cell carcinoma (SCC) is rarely reported. We present here a case of CLL with multiple SCC on the face. Subsequent studies demonstrated the patient to have a trisomy 12 identified in bone marrow specimen.

Therapeutic Experience of Bing-Neel Syndrome Associated with Waldenstrom's Macroglobulinemia

Waldenstrom's macroglobulinemia is an uncommon low-grade B-cell lymphoproliferative disorder in which monoclonal immunoglobulin M is produced. Neurological symptoms due to hyperviscosity are frequent manifestations of Waldenstrom's macroglobulinemia. However, central nervous system infiltration by plasmacytoid lymphocytes (Bing-Neel syndrome) has only rarely been reported. We report a case of a 51-yr-old woman suffering from Waldenstrom's macroglobulinemia who complained of persistant headache. Brain magnetic resonance imaging revealed an extra-axial soft tissue mass along the left cavernous sinus, left tentorium, right tentorium, and falx cerebri. A stereotactic biopsy of dural tissue from the falx was performed and showed plasmacytoid lymphocyte infiltration. The patient became symptom- free with irradiation of the whole brain followed by chemotherapy with fludarabine.

Differential diagnosis of Waldenstrom's macroglobulinemia from other low-grade B-cell lymphoproliferative disorders

Waldenstrom's macroglobulinemia (WM) is a rare lymphoproliferative disorder (LPD) characterized by lymphoplasmacytic infiltration of the bone marrow (BM) and/or occasionally other tissues and by the presence of a serum monoclonal IgM. The disease belongs to the lymphoplasmacytic lymphoma (LPL) subtype. Whether WM is indeed a separate entity or is merely an IgM-secreting subtype of low-grade B-cell lymphoma is still controversial. In our series of 67 patients, WM has a long median overall survival of 110 months, and the male/female ratio is 1.2/1. Clinical features include a wide spectrum of manifestations, many of which may be common to other LPDs. Differential diagnosis is based on: (1) clinical and laboratory features (anemia, organomegaly, lymphadenopathy, IgM paraproteinemia), (2) cell morphology (lymphocytes, lymphoplasmacytes, few plasma cells), (3) histopathology of bone marrow or lymph node, (4) immunophenotype (CD5 expression and the intensity of CD5, CD20, and CD79b antigens may help in discrimination from other LPDs and atypical CLL), and (5) characteristic genetic features (present in other LPDs). Based on the former, diagnosis is usually easy. It may be harder in LPL cases not secreting IgM. We consider that WM should be, for the time being, handled as a separate entity. Further studies are necessary. Semin Oncol 30:201-205. © 2003 Elsevier Inc. All rights reserved.

Cyclin D3 is a target gene of t(6;14)(p21.1;q32.3) of mature B-cell malignancies

AbstractChromosomal translocation t(6;14)(p21.1;q32.3) has been reported as a rare but recurrent event not only in myeloma and plasma cell leukemia but also in diffuse large B-cell non-Hodgkin lymphoma (B-NHL) (diffuse large B-cell lymphoma [DLBCL]) and splenic lymphoma with villous lymphocytes (SLVL); however, the nature of the target gene(s) has not been determined. This study identified t(6;14)(p21.1;q32.3) in 3 cases of transformed extranodal marginal zone B-NHL, in 1 case of SLVL, and in 1 case of a low-grade B-cell lymphoproliferative disorder. In a sixth case, a CD5+ DLBCL, the translocation was identified by molecular cloning in the absence of cytogenetically detectable change. Two chromosomal translocation breakpoints were cloned by using long-distance inverse polymerase chain reaction methods. Comparison with the genomic sequence for chromosome 6p21.1 showed breakpoints approximately 59 and 73.5 kilobases 5′ of the cyclin D3 (CCND3) gene with no other identifiable transcribed sequences in the intervening region. Although Southern blotting with derived genomic 6p21.1 probes failed to detect other rearrangements, fluorescent in situ hybridization assays, using BAC (bacterial artificial chromosome) clones spanning and flanking theCCND3 locus, along with probes for IGHconfirmed localization of 6p21.1 breakpoints within the same region, as well as fusion of the CCND3 and IGH loci. Furthermore, in all cases, high-level expression of CCND3was demonstrated at RNA and/or protein levels by Northern and Western blotting and by immunohistochemistry. These data implicateCCND3 as a dominant oncogene in the pathogenesis and transformation in several histologic subtypes of mature B-cell malignancies with t(6;14)(p21.1;q32.3) and suggest thatCCND3 overexpression seen in about 10% of DLBCL cases may have a genetic basis.

A Translocation Breakpoint at Chromosome Band 12q13 Associated with B-Cell Chronic Lymphocytic Leukemia

Low-grade B-cell lymphoproliferative disorders are frequently associated with an extra copy of chromosome 12. This well-documented acquired anomaly is one of the most specific numerical chromosome alterations to occur in human hematological malignancies. We have cytogenetically characterized bone marrow and peripheral blood cells from a patient with B-cell chronic lymphocytic leukemia (CLL) having a unique acquired translocation involving chromosomes 6 and 12, t(6;12)(p21.3;q13), which implicates band 12q13 as the site of the gene(s) important in this lymphoproliferative B-cell disorder. Aneuploidy, in the form of trisomy of chromosome 12, is not a requirement for neoplastic transformation in B-cell CLL, but gene rearrangement (present case) or nondisjunctional acquisition of additional copies of defective genes on chromosome 12 at band q13 may be involved in the genesis or progression of this disorder.