A Unique Case of Primary Extranodal Marginal Zone Lymphoma of the Anal Canal.

Marginal zone lymphomas represent approximately 10-12% of all B-cell lymphomas. Extranodal marginal zone lymphomas (EMZL) or mucosa-associated lymphoid tissue (MALT) lymphomas are the most common subtype. Almost half of all MALT lymphomas arise in the gastrointestinal (GI) tract and, while the stomach is the most common site of GI involvement, the small and large intestines can also be involved. Rare cases of MALT lymphoma involving the rectum have been reported; however, to our knowledge, involvement of the anal canal has never been reported in the literature. Here, we describe a unique case of MALT lymphoma of the anal canal. Infectious agents have been implicated in the pathogenesis of MALT lymphomas, possibly through persistent antigenic stimulation of the area; however, in our case no such infection was documented.

Study of bone metabolism and angiogenesis in patients undergoing high-dose chemotherapy/autologous hematopoietic stem cell transplantation.

OBJECTIVES: As the interaction between hematopoietic stem cells (HSCs) and endosteal and endothelial niches in HSCs homing is essential, we aimed to study bone turnover and angiogenesis in 29 patients with lymphoma/multiple myeloma undergoing hematopoietic stem cell transplantation (HSCT). METHODS: Serum samples were collected before high-dose chemotherapy (HDT), at the end of HDT, after HSC infusion, at the nadir of myelotoxicity, and at engraftment. Bone metabolism (CTX, TRACP-5b, bALP, OC, DKK1, RANKL, OPG), and angiogenesis (Ang1, Ang2) markers were measured. These markers were also measured in 21 control patients before and after conventional chemotherapy. RESULTS AND CONCLUSIONS: Bone resorption declined during HSCT (decrease in TRACP-5b [P < .001] and CTX [P = .006]). Bone formation declined as well (decrease in bALP and OC [P < .001 for both]). RANKL/OPG ratio, an indicator of osteoclastic activation, did not change significantly (P = .5). Ang1/Ang2 ratio, a vessel equilibrium marker, decreased significantly (P < .001) suggesting endothelial destabilization. The changes observed in the control group were similar except of bALP and RANKL/OPG ratio. Moreover, Ang1/Ang2 ratio on the day after HSC infusion strongly correlated with time to neutrophil and platelet engraftment (P < .001 for both). Conclusively, bone turnover and vessel destabilization represent important events during HSCT probably reflecting the effect of chemotherapy.

Protein Z (PZ) and plasminogen activator inhibitor-1 (PAI-1) plasma levels in patients with previously untreated Hodgkin lymphoma (HL).

PURPOSE: The role of Protein Z (PZ) in conditions, such as thrombosis, inflammation or cancer, is under investigation. Plasminogen Activator Inhibitor-1 (PAI-1) is an acute phase reactant that promotes thrombosis and tumorigenesis. Subject of this work was to study PZ and PAI-1 in patients with Hodgkin Lymphoma (HL), a malignancy with inflammatory background and relatively low incidence of thrombosis. METHODS: Newly diagnosed patients were enrolled in the study. Healthy individuals were used as controls. RESULTS: PZ levels were higher in patients compared to controls (not significantly), while PAI-1 levels were significantly higher in patients. Both PZ and PAI-1 concentrations did not correlate with most of patients' characteristics. Lower PZ levels at diagnosis were associated with presence of B symptoms and positive final positron emission tomography (PET) and higher baseline PAI-1 levels with positive final PET, too. PZ had a declining trend, but PAI-1 increased initially and decreased thereafter, during the treatment period. CONCLUSIONS: Conclusively, PAI-1, but not PZ, seems to be an acute phase protein in HL. Lower PZ and higher PAI-1 levels at diagnosis may be indicative of aggressive disease. These results need further verification.

Prognostic Implication of the Absolute Lymphocyte to Absolute Monocyte Count Ratio in Patients With Classical Hodgkin Lymphoma Treated With Doxorubicin, Bleomycin, Vinblastine, and Dacarbazine or Equivalent Regimens.

Low absolute lymphocyte count (ALC) to absolute monocyte count (AMC) ratio (ALC/AMC) is an independent prognostic factor in Hodgkin lymphoma (HL), but different cutoffs (1.1, 1.5, and 2.9) have been applied. We aimed to validate the prognostic significance of ALC/AMC in 537 homogenously treated (doxorubicin, bleomycin, vinblastine, and dacarbazine or equivalents ± radiotherapy) classical HL patients at various cutoffs. The median ALC/AMC was 2.24 (0.44-20.50). The median AMC was 0.653 × 10(9)/L (0.050-2.070). Lower ALC/AMC was associated with established markers of adverse prognosis. In total, 477 (89%), 418 (78%), and 189 (35%) patients had an ALC/AMC ratio of ≥1.1, ≥1.5, and ≥2.9; respectively; 20% had monocytosis (≥0.9 × 10(9)/L). Ten-year time to progression (TTP) was 77% versus 55% for patients with ALC/AMC ≥1.1 and <1.1 (p = .0002), 76% versus 68% for ALC/AMC ≥1.5 and <1.5 (p = .049), 77% versus 73% for ALC/AMC ≥2.9 and <2.9 (p = .35), and 79% versus 70% for ALC/AMC ≥2.24 and <2.24 (p = .08), respectively. In stages ΙΑ/ΙΙΑ and in patients ≥60 years old, ALC/AMC had no significant effect on TTP. In advanced stages, ALC/AMC was significant only at the cutoff of 1.1 (10-year TTP 67% vs. 48%; p = .016). In younger, advanced-stage patients, the differences were more pronounced. In multivariate analysis of TTP, ALC/AMC < 1.1 (p = .007) and stage IV (p < .001) were independent prognostic factors; ALC/AMC was independent of International Prognostic Score in another model. ALC/AMC was more predictive of overall survival than TTP. At the cutoff of 1.1, ALC/AMC had independent prognostic value in multivariate analysis. However, the prognostically inferior group comprised only 11% of patients. Further research is needed prior to the widespread use of this promising marker.

The presence of CD55- and/or CD59-deficient erythrocytic populations in patients with rheumatic diseases reflects an immune-mediated bone-marrow derived phenomenon.

BACKGROUND: Complement has the potential to provoke severe impairment to host tissues, as shown in autoimmune diseases where complement activation has been associated with diminished CD55 and/or CD59 expression on peripheral blood cell membranes. The aim of this study was to evaluate the presence of CD55- and/or CD59-deficient erythrocytic populations in patients with different rheumatic diseases and to investigate possible correlations with clinical or laboratory parameters. MATERIAL AND METHODS: CD55 and CD59 expression was evaluated in erythrocytes of 113 patients with rheumatic diseases, 121 normal individuals, and 10 patients with paroxysmal nocturnal hemoglobinuria (PNH) using the Sephacryl gel microtyping system. Ham and sucrose tests were also performed. RESULTS: Interestingly, the majority of patients (104/113, 92%) demonstrated CD55- and/or CD59-deficient erythrocytes: 47 (41.6%) with concomitant deficiency of CD55 and CD59, 50 (44.2%) with isolated deficiency of CD55, and 6 (6.2%) with isolated deficiency of CD59. In normal individuals, only 2 (1%) had concomitant CD55/CD59 negativity and 3 (2%) had isolated CD55 or CD59 deficiency. All PNH patients exhibited simultaneous CD55/CD59 deficiency. Positive Ham and sucrose tests were found only in PNH patients. There was no association between the CD55- and/or CD59-deficient erythrocytes and hemocytopenias or undergoing treatment. However, CD55 expression significantly influenced hemoglobin values (F=6.092, p=0.015). CONCLUSIONS: This study provides evidence supporting the presence of erythrocytes with CD55 and/or CD59 deficiency in patients with rheumatic diseases. Moreover, CD55 deficiency on red cells influences hemoglobin concentration. Further studies using molecular techniques will clarify the exact pathophysiological mechanisms of this deficiency.

Isolated central nervous system relapses in primary mediastinal large B-cell lymphoma after CHOP-like chemotherapy with or without Rituximab.

Central nervous system (CNS) involvement in patients with primary mediastinal large B-cell (PMLBCL) lymphoma is a rare event, occurring in approximately 6% of patients, on the basis of the review of the literature prior to induction of Rituximab. The aim of this retrospective study was to describe the incidence of CNS relapse among 100 consecutive patients with PMLBCL who were treated with R-CHOP ± RT in comparison to patients treated with CHOP ± RT (n = 45) in 11 hospitals in Greece. Two patients experienced a CNS relapse, representing an overall frequency of 2.0% in R-CHOP treated patients and a 2-year actuarial incidence of 2.3%. Both patients had isolated CNS relapses. The incidence of CNS relapse after CHOP without Rituximab was 2/45 (4.4%) for a 2-year actuarial incidence of 7.5% (p = 0.29). Again, both patients had isolated CNS relapses. Parenchymal-only localizations accounted for 3/4 cases. Risk factors for CNS involvement could include leukocytosis, poor performance status and higher age-adjusted International Prognostic Index, although their impact was weakened by competing risk survival analysis. Both patients relapsing after R-CHOP required CNS radiotherapy to achieve a complete remission and be forwarded to high-dose therapy and autologous stem cell transplantation: They are both alive and disease-free 18 and 23 months after CNS relapse. Both cases relapsing after CHOP without Rituximab were salvaged by CNS radiotherapy (one also received intrathecal chemotherapy) entering long-term remissions. In conclusion, CNS relapses are rare in PMLBCL tending to be isolated in the CNS, probably reflecting the persistence of latent CNS disease than dissemination of resistant disease. The impact of Rituximab in reducing CNS relapses remains unknown. Established risk factors for CNS involvement in aggressive lymphomas may not be helpful in assessing the risk of CNS recurrence in this disease. Routine CNS prophylaxis is not probably required in PMLBCL.

Circulating angiopoietin-1 to angiopoietin-2 ratio is an independent prognostic factor for survival in newly diagnosed patients with multiple myeloma who received therapy with novel antimyeloma agents.

The circulating levels of several angiogenic cytokines [angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2), vascular endothelial growth factor (VEGF), angiogenin and basic fibroblast growth factor (bFGF)] were evaluated in 174 consecutive patients with newly diagnosed, symptomatic, multiple myeloma (MM). Circulating levels of Ang-1/Ang-2 were reduced in myeloma patients compared to controls, whereas VEGF and angiogenin levels were increased. Reduced angiopoietin-1/angiopoietin-2 ratio correlated with advanced disease features including international staging system (ISS)-3 stage, renal impairment and extensive bone disease. Based on immunohistochemical results in 20 patients (10 with the higher and 10 with the lower values of circulating angiopoietin-2) we found that angiopoietin-2 is expressed by myeloma cells and correlates with increased microvessel density in subsets of patients. Furthermore, Ang-1/Ang-2 ratio correlated with survival. Patients with circulating Ang-1/Ang-2 below or equal to the median value (6.03) had a median survival of 26.3 months compared to 53 months of all others (p = 0.002). Interestingly, this was mainly observed in patients who received first-line therapy with novel agent-based regimens (65% of our patients). Furthermore, a subset of ISS-3 patients with serum Ang-1/Ang-2 above the median value had favourable prognosis (median survival: 45 months versus 17 months of all others; p = 0.0001). The multivariate analysis revealed that low Ang-1/Ang-2 ratio could independently predict for inferior survival in our cohort of patients (relative risk (RR) 2.07, 95% CI 1.50-2.42; p < 0.001). These results highlight the role of angiopoietins pathway in the biology of MM and reveal novel targets for the development of antimyeloma agents.

Elevated circulating sclerostin correlates with advanced disease features and abnormal bone remodeling in symptomatic myeloma: reduction post-bortezomib monotherapy.

Sclerostin is a Wingless and Int-1 inhibitor, which is produced by osteocytes and inhibits osteoblast-driven bone formation. Sclerostin is implicated in the pathogenesis of bone loss in metabolic bone disorders but there is no information for its effect on multiple myeloma (MM)-related osteolytic disease. We evaluated circulating sclerostin in 157 newly diagnosed patients with symptomatic myeloma, in 25 with relapsed myeloma who received bortezomib monotherapy, in 21 patients with monoclonal gammopathy of undetermined significance (MGUS), and in 21 healthy controls. Patients with active myeloma had elevated circulating sclerostin compared to MGUS patients and controls (p < 0.01). MM patients who presented with fractures at diagnosis (n = 34) had very high levels of circulating sclerostin compared with all others (p < 0.01), whereas sclerostin correlated negatively with bone specific alkaline phosphatase (a bone formation marker; r = -0.541, p < 0.0001) and positively with C-telopeptide of collagen type-1 (a bone resorption marker; r = 0.524, p < 0.0001). Patients with International Staging System (ISS)-3 disease had higher circulating sclerostin compared to ISS-1 and ISS-2 MM (p = 0.001). Furthermore, patients with high sclerostin (upper quartile, n = 40) had a median survival of 27 months versus 98 months of all others (p = 0.031). Relapsed MM patients had higher levels of circulating sclerostin even compared to newly diagnosed patients (p < 0.01). Bortezomib monotherapy resulted in a reduction of sclerostin by almost 50% in both responders and non-responders. These results suggest that patients with active myeloma have elevated circulating sclerostin, which correlated with advanced disease features including severe bone disease. Our study indicates sclerostin as a possible target for the development of novel therapies to enhance osteoblast function in myeloma.

Rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone with or without radiotherapy in primary mediastinal large B-cell lymphoma: the emerging standard of care.

UNLABELLED: More aggressive treatment approaches (methotrexate, cytarabine, cyclophosphamide, vincristine, prednisone, and bleomycin [the MACOP-B regimen] or consolidation with high-dose therapy and autologous stem cell transplantation) have been considered to be superior to cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) in patients with primary mediastinal large B-cell lymphoma (PMLBCL). Rituximab-CHOP (R-CHOP) is the standard of care for diffuse large B-cell lymphoma, whereas efficacy in PMLBCL has not been adequately confirmed. PATIENT AND METHODS: Seventy-six consecutive PMLBCL patients who received R-CHOP with or without radiotherapy (RT) were compared with 45 consecutive historical controls treated with CHOP with or without RT. Baseline characteristics of the two groups were balanced. RESULTS: The rate of early treatment failure was much lower with R-CHOP with or without RT (9% versus 30%; p = .004). The 5-year freedom from progression rate after R-CHOP with or without RT was 81%, versus 48% for CHOP with or without RT (p < .0001). The 5-year event-free survival rates were 80% and 47% (p < .0001) and the 5-year overall and lymphoma-specific survival rates were 89% and 69% (p = .003) and 91% and 69% (p = .001), respectively, with only seven of 76 lymphoma-related deaths. Among R-CHOP responders, 52 of 68 received RT. CONCLUSIONS: Based on these results, most patients with PMLBCL appear to be cured by R-CHOP in 21-day cycles with or without RT, which could be the current standard of care. Therefore, the need for more aggressive treatment strategies is questionable unless high-risk patients are adequately defined. Further studies are required to establish the precise role of RT.

Antiretroviral activity of 5-azacytidine during treatment of a HTLV-1 positive myelodysplastic syndrome with autoimmune manifestations.

Myelodysplastic syndromes (MDS) are often accompanied by autoimmune phenomena. The underlying mechanisms for these associations remain uncertain, although T cell activation seems to be important. Human T-lymphotropic virus (HTLV-1) has been detected in patients with myelodysplastic syndromes, mostly in regions of the world which are endemic for the virus, and where association of HTLV-1 with rheumatological manifestation is not rare. We present here the case of a 58 year old man who presented with cytopenias, leukocytoclastic vasculitis of the skin and glomerulopathy, and was diagnosed as MDS (refractory anemia with excess blasts - RAEB 1). The patient also tested positive for HTLV-1 by PCR. After 8 monthly cycles of 5-azacytidine he achieved a complete hematologic remission. Following treatment, a second PCR for HTLV-1 was carried out and found to be negative. This is the first report in the literature of a HTLV-1-positive MDS with severe autoimmune manifestations, which was treated with the hypomethylating factor 5-azacitidine, achieving cytogenetic remission with concomitant resolution of the autoimmune manifestations, as well as HTLV-1-PCR negativity. HTLV-1-PCR negativity may be due to either immune mediated clearance of the virus, or a potential antiretroviral effect of 5-azacytidine. 5-azacytidine is known for its antiretroviral effects, although there is no proof of its activity against HTLV-1 infection in vivo.

Translocation t(12;13)(p13;q14) in a patient with imatinib-sensitive MDS/MPD associated with resistance to treatment: review of the literature.

The category of myelodysplastic syndromes/myeloproliferative diseases (MDS/MPD) is a relatively new group of malignant hematologic diseases developed by the World Health Organization. These hematologic disorders lack the BCR/ABL fusion gene, although they can be associated with chromosomal translocations that involve genes encoding other protein kinases. Imatinib mesylate was recognized as a potent inhibitor of some of those kinases. We present a patient with a previously treated acute myeloid leukemia, who, after a 9-year-long remission, developed an MDS/MPD with normal karyotype, which initially responded to imatinib mesylate. Translocation t(12;13)(p12;q14) was detected after loss of response to imatinib treatment. Translocation t(12;13) is rare. It has been described in several hematologic malignancies including chronic myelomonocytic leukemia but not in MDS/MPD, previously described as Philadelphia-negative chronic myelogenous leukemia. Moreover, the correlation of this molecular abnormality with loss of efficacy of imatinib is unique in the literature.

Severe thrombocytopenia related to trastuzumab infusion.

BACKGROUND: Trastuzumab is a humanized, monoclonal antibody that interferes with the HER2/neu receptor and binds selectively to the HERB2 protein which causes uncontrolled proliferation of malignant breast cells. CASE REPORT: We report a case of severe thrombocytopenia related to trastuzumab administration. Three days after the first dose of single-agent trastuzumab, the patient was admitted to the hospital with nose bleeding, petechiae and platelet counts of 5 × 109/L. CONCLUSIONS: The patient showed a self-limiting trastuzumab-related thrombocytopenia. Among the reported cases of trastuzumab-induced severe thrombocytopenia, this patient is the only one who did not interrupt trastuzumab treatment. It is possible that our patient showed progressive reduction of immune-mediated thrombocytopenia caused by trastuzumab administration.

A European consensus report on blood cell identification: terminology utilized and morphological diagnosis concordance among 28 experts from 17 countries within the European LeukemiaNet network WP10, on behalf of the ELN Morphology Faculty.

This paper describes the methodology used to develop a consensual glossary for haematopoietic cells within Diagnostics-WP10 of European-LeukemiaNet EU-project. This highly interactive work was made possible through the use of the net, requiring only a single two-day meeting of actual confrontation and debate. It resulted in the production of a freely accessible tool that could be useful for training as well as harmonization of morphological reports in onco-haematology especially, without geographic limitation, not limited to European countries. Moreover, this collective work resulted in the production of a consensus statement, taking into account individual practices, collegial agreement and literature data.

Successful treatment of Immune Thrombocytopenic Purpura (ITP) with the thrombopoietin-mimetic romiplostim.

BACKGROUND: Romiplostim is a second-generation thrombopoietic receptor agonist that exerts its therapeutic effect by stimulating megakaryopoiesis. CASE REPORT: We report a patient with immune thrombocytopenic purpura refractory to other therapies including splenectomy, which was successfully managed with romiplostim. More specifically, the patient's platelet count showed a 3-fold increase within 7 days following the first dose of romiplostim (from 33 x 10(9)/l to 96 x 10(9)/l). CONCLUSIONS: Romiplostin is a new trombopoietin peptide mimetic drug, which seems to be very effective for the management of refractory chronic ITP in adults.

Non-Inherited Maternal Antigens Identify Acceptable HLA Mismatches: A New Policy for the Hellenic Cord Blood Bank.

BACKGROUND: During pregnancy, the maternal-fetal contact may lead to the development of tolerance against the maternal human leukocyte antigen (HLA) that is not inherited by the fetus. These non-inherited maternal antigens (NIMAs) define acceptable HLA mismatches; therefore, the number of HLA phenotypes that are suitable matches for patients who need a hematopoietic stem cell transplant could be increased. Cord blood unit (CBU) transplantations to patients mismatched for a HLA loci, but similar to the ΝΙΜAs of the CBU, have a prognosis similar to 6/6-matched ones. METHODS: The Hellenic Cord Blood Bank (HCBB) identified the maternal HLA of 380 cord blood donors, specifying the NIMA haplotypes of the related cryostored CBUs. RESULTS: The HCBB extended the pool of HLA phenotypes through the generation of unique virtual phenotypes (VPs). A "VP database" was set up, using Microsoft Office-Access™, in order to provide NIMA-matched CBUs for potential recipients. The effectiveness of VPs' matching was tested in 80 Greek patients. CONCLUSION: This methodology may contribute to the increase of the number of available CBUs for patients, in the case where there is no available CBU, or in case an additional one is needed. Through this method, the CBUs could be used faster and more effectively, rather than being cryostored for long periods of time.

A retrospective study of azacitidine treatment in patients with intermediate-2 or high risk myelodysplastic syndromes in a real-world clinical setting in Greece.

For patients with intermediate-2 or high risk [according to the International Prognostic Scoring System (IPSS)] myelodysplastic syndromes (MDS), azacitidine treatment offers hematologic improvement (HI) but also has the potential to modify the natural disease course. 'RETRO-AZA-MDS-001', a retrospective chart review study was conducted from February to November 2012 across 17 hematology hospital sites of Greece, aiming to evaluate the clinical efficacy and safety profile of azacitidine in IPSS intermediate-2/high risk adult MDS patients in routine care. A total of 88 patients (median age 74.7 years), with a 6.6 month median (range 1.0-49.5) azacitidine treatment duration were enrolled. The overall response rate [complete response (CR), marrow CR and partial response] was 37.7% (23/61), while stable disease with HI was achieved by 21.3% (13/61). The HI rate was 33.0 % (29/88) and the AML transformation rate 6.8% (6/88). Of the transfusion-dependent patients, 7.3% (3/41) became transfusion-independent during azacitidine treatment. The incidence of non-serious and serious adverse events related to azacitidine was 50.0 and 42.0%, respectively. Patients not receiving prior ESA therapy were expected to be 7.6 times more likely to achieve a clinical response (p = 0.012). The study corroborates the favorable risk-benefit profile of azacitidine for intermediate-2/high risk MDS patients in routine clinical practice.

Evaluation of the clinical relevance of the expression and function of P-glycoprotein, multidrug resistance protein and lung resistance protein in patients with primary acute myelogenous leukemia.

The multidrug resistance (MDR) transporter-proteins P-glycoprotein (Pgp), multidrug resistance protein (MRP) and lung resistance protein (LRP) have been associated with treatment failure. The aim of this study was to investigate prospectively the clinical significance of expression and function of the MDR proteins, considering other prognostic factors, such as age, immunophenotype, and cytogenetics. Mononuclear cells of peripheral blood or bone marrow from 61 patients with de novo acute myelogenous leukemia (AML) were analyzed. The monoclonal antibodies JSB1, MRPm6 and LRP56 were used for expression studies. Accumulation and retention studies were performed using the substrates Daunorubicin, Calcein-AM, Rhodamine-123 and DiOC(2) in the presence or absence of the modifiers Verapamil, Genistein, Probenecid, BIBW22S and PSC833. Induction treatment consisted of a 3+7 combination of Ida/Ara-C for patients < or = 60 years of age and a 3+5 Ida/VP-16 combination per OS for patients >60. MDR function was expressed as the ratio of mean fluorescence intensity substrate in the presence of modifier over the substrate alone (resistance index, RI). Patients with advanced age, low CD15 expression and high RI for accumulation of DiOC(2) in the presence of BIBW22S had significantly lower complete remission (CR) rates. No factor was prognostic for event-free survival analysis, which was limited to remitters only. Overall survival was shorter in patients with advanced age, poor prognosis cytogenetics, high CD7 expression, and high RI for Daunorubicin efflux modulated by Verapamil. These results suggest that MDR transporter-proteins have a limited role in the treatment failure of patients treated with Idarubicin-based regimens.

Leukemogenic risk of hydroxyurea therapy as a single agent in polycythemia vera and essential thrombocythemia: N- and K-ras mutations and microsatellite instability in chromosomes 5 and 7 in 69 patients.

Polycythemia vera (PV) and essential thrombocythemia (ET) are chronic myeloproliferative diseases that carry intrinsically the potential for leukemic transformation. The aims of this study were (1) to detect involvement of N- and K-ras mutations in codons 12 and 13 in the pathogenesis of the chronic and blastic phases of PV and ET, (2) to study the occurrence of microsatellite instability (MSI) in chromosomes 5 and 7 during the chronic phase and blastic transformation of the disease, and (3) to examine the incidence of leukemia in patients treated with hydroxyurea (HU). Samples of PV and ET patients were analyzed with a polymerase chain reaction. No N- or K-ras mutations were detected. A positive score for MSI in chromosome 7 was found in 1 patient with PV during leukemic transformation. Three of 69 patients developed acute myelogenous leukemia, 2 with PV and 1 with ET. As of this report, the overall incidence of leukemic transformation is 5.7% (2/35 patients) in PV and 3.3% (1/30 patients) in ET patients treated with HU. These results indicate that (1) MSI is a genetic marker that can be detected, even in a small group of patients, at the blastic phase of the disease and (2) no increased leukemogenicity was noted in this group of patients treated with HU.

Unusual association between increased bone resorption and presence of paroxysmal nocturnal hemoglobinuria phenotype in multiple myeloma.

Paroxysmal nocturnal hemoglobinuria (PNH) clones deficient in glycosylphosphatidylinositol-anchored molecules, including CD55 and CD59, have been previously described in patients with multiple myeloma (MM). The aim of this study was to investigate the possible association between existence of the PNH phenotype and myeloma bone disease. Forty-three patients with newly diagnosed MM were the subjects of the study. Radiographic evaluation of the skeleton was performed in all patients at diagnosis. The following biochemical markers were measured: bone resorption markers (tartrate-resistant acid phosphatase isoform 5b [TRACP-5b]and N-terminal cross-linking telopeptide of type-I collagen [NTX]), bone formation markers (bone alkaline phosphatase [bALP] and osteocalcin [OC]), osteoprotegerin (OPG), soluble receptor activator of nuclear factor KB ligand (sRANKL), and interleukin 6 (IL-6). Detection of CD55- and/or CD59-deficient red cell populations was performed after diagnosis. Patients with MM had elevated mean baseline NTX, TRACP-5b, sRANKL, and IL-6 levels compared with controls, whereas the mean values of bALP, OC, and OPG were significantly decreased. Four patients had no osteolytic lesions, whereas 8 patients had 1 to 3 lytic lesions, and 31 patients had more than 3 lytic lesions and/or pathologic fractures in the skeletal survey. CD55- and/or CD59-deficient red cell populations were observed in 56% of patients with MM. There was a strong correlation between the presence of PNH-like erythrocytes and increased bone resorption, as measured by NTX, TRACP-5b, and sRANKL/OPG ratio (P < .03, P < .02, and P < .02, respectively). There was also a significant correlation between PNH phenotype and severe bone disease (P < .02). These results suggest that there is a possible link between PNH phenotype and increased osteoclastic activity in MM owing to a potential effect of myeloma microenvironment on a preexisting PNH clone. Further studies are required for clarifying this phenomenon and investigating possible mechanisms of this unusual association.