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Dive into the research topics where Konstantinos Konstantopoulos is active.

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Featured researches published by Konstantinos Konstantopoulos.


Annals of Hematology | 2001

Waldenström's macroglobulinemia: clinical course and prognostic factors in 60 patients: Experience from a single hematology unit

Marie-Christine Kyrtsonis; Theodoros P. Vassilakopoulos; Maria K. Angelopoulou; Marina P. Siakantaris; Flora N. Kontopidou; Maria N. Dimopoulou; Vassiliki A. Boussiotis; Despina Gribabis; Konstantinos Konstantopoulos; George Vaiopoulos; Phaedon Fessas; Christos Kittas; Gerassimos A. Pangalis

Abstract. Waldenströms macroglobulinemia (WM) is a lymphoplasmacytic lymphoma characterized by the presence in patients serum of an IgM monoclonal component. We report on our experience with 60 WM patients, focusing on their clinical findings, response to treatment, and the possible identification of prognostic factors. Of these patients, 70% presented with fatigue, and lymphadenopathy was observed in 22%, splenomegaly in 18%, hepatomegaly in 13%, and extranodal site of involvement in 6%. Bleeding tendency was seen in 17%, infections in 17%, hyperviscosity syndrome in 12%, and cardiac failure in 25% of the patients. The median of IgM levels was 30xa0g/l with hypoalbuminemia in 20% of cases, hypogammaglobulinemia in 27%, polyclonal hypergammaglobulinemia in 15%, kappa light-chain restriction in 78%, and Bence-Jones proteinuria in 54%. Anemia was frequent (85%), followed by leukocytosis (18%), lymphocytosis (12%), leukopenia (10%), and thrombocytopenia (10%). Cryoglobulinemia and autoimmune hemolytic anemia were encountered in 5%. In all cases but two, bone marrow was involved. Of 50 patients initially treated with intermittent oral chlorambucil, 46 (92%) responded. Median overall survival was 108xa0months. Factors associated with adverse prognosis were age ≥65xa0years (p=0.06), presence of lymphadenopathy (p=0.06), bone marrow infiltration ≥50% (p=0.007), international prognostic index (IPI) ≥3 (p=0.0001), and Morels scoring system (p=0.04). Concluding, we found in this series of WM patients that chlorambucil is an effective treatment and that the parameters of age, lymphadenopathy, percentage of bone marrow infiltration, IPI, and Morels scoring system carry prognostic significance.


Annals of Oncology | 2014

Significant improvement in the survival of patients with multiple myeloma presenting with severe renal impairment after the introduction of novel agents

M. A. Dimopoulos; Sosana Delimpasi; Eirini Katodritou; A. Vassou; Marie-Christine Kyrtsonis; P. Repousis; Zafiris Kartasis; A. Parcharidou; Michalis Michael; Eurydiki Michalis; Dimitra Gika; Argiris Symeonidis; A. Pouli; Konstantinos Konstantopoulos; Evangelos Terpos; Efstathios Kastritis

BACKGROUNDnRenal impairment (RI) is a common presenting complication of multiple myeloma (MM); the availability of new treatments has improved the outcomes of patients with MM; however, their impact on the survival of patients who present with RI has not been extensively studied.nnnPATIENTS AND METHODSnWe analyzed the characteristics and outcomes of 1773 consecutive unselected patients who were treated for symptomatic myeloma since January 1990.nnnRESULTSnAlthough there was a significant increase in the proportion of patients of advanced age in the more recent periods, the frequency of RI as well as the proportion of patients who presented with severe RI (eGFR < 30 ml/min/1.73 m(2)) remained unchanged around 18%. Thus, after adjustment for age, there was a decrease in the risk of severe RI at presentation after 2000. Myeloma response rates (≥PR) to frontline therapy have substantially increased, and this was translated in a significant increase in the median survival. Specifically for patients with severe RI, the median OS has improved from 18 and 19.5 months in the 1990-1994 and 1995-1999 to 29 and 32 months for the periods 2000-2004 and after 2005 (P = 0.005). Severe RI was associated with a high risk of early death (12% versus 7% for patients with moderate RI versus 3% for patients with mild or no RI (P < 0.001), especially among older patients, and has remained unchanged over time.nnnCONCLUSIONSnThere has been a major improvement in the survival of patients with severe RI in the past decade, despite the increasing numbers of patients of advanced age. However, the risk of early death remains high in patients with severe RI, especially in the elderly.


Dermatology | 2002

Pityriasis rosea associated with imatinib (STI571, Gleevec).

Konstantinos Konstantopoulos; A. Papadogianni; Maria N. Dimopoulou; C. Kourelis; John Meletis

A tyrosine kinase inhibitor (STI571, Gleevec) has recently been applied in the treatment of chronic myeloid leukemia. We present the first reported case of pityriasis rosea occurring as a reaction to Gleevec in a woman with blast crisis of this disorder. It is suggested that although coincidental, this exanthem may be due to this agent.


Haematologia | 2001

Detection of CD55 and/or CD59 deficient red cell populations in patients with aplastic anaemia, myelodysplastic syndromes and myeloproliferative disorders.

John Meletis; Evangelos Terpos; Michalis Samarkos; Christos Meletis; Konstantinos Konstantopoulos; Komninaka; Effie Apostolidou; Olga Benopoulou; Konstantinos Korovesis; Despina Mavrogianni; Eleni Variami; Xenophon Yataganas; Dimitris Loukopoulos

Paroxysmal nocturnal haemoglobinuria (PNH) is an acquired clonal stem cell disorder characterized by intravascular haemolysis, venous thrombosis, marrow hypoplasia, frequent episodes of infection, and rarely leukaemic conversion. At the cellular level, PNH is characterized by the decrease or absence of glycosylphosphatidylinositol (GPI)-anchored molecules, such as CD55 and CD59, from the cell surface. PNH-like clones have been described in various haematological disorders. The link between PNH and aplastic anaemia (AA) has been established but the relationship of PNH with myelodysplastic syndromes (MDS) or myeloproliferative disorders (MPD) remains unclear. In this study, the presence of CD55 and/or CD59 defective (PNH-like) red cell populations was evaluated in 21 patients with AA, 133 with MDS, 197 with MPD, 7 with PNH and in 121 healthy blood donors using the Sephacryl Gel Test microtyping system. Red cell populations deficient in both molecules CD55 and CD59 were detected in 33.3% of AA patients, in 16.5% of MDS patients (50% with hypoplastic bone marrow), in 14.2% of MPD patients (more often in essential thrombocythemia, 21.2%) and in all PNH patients. CD55 deficient red cell populations were found in 14.2% of patients with AA, 12.7% of patients with MDS and 21.3% of patients with MPD. CD59 deficient populations were found in 9.5% of AA patients, 2.2% of MDS patients and 2% of MPD patients. These results indicate an association between PNH, AA and MDS or even between PNH and MPD. Further investigation is necessary to work out the mechanisms of this association, and to define classification criteria for borderline cases, where diagnosis is difficult.


Annals of Hematology | 2004

Hemodynamic assessment of splenomegaly in β-thalassemia patients undergoing splenectomy

Athanasios Aessopos; Dimitrios Farmakis; Maria Tsironi; Spyros Deftereos; Stergios Tassiopoulos; Konstantinos Konstantopoulos; John Rombos; Efstathios Papalambros

Splenomegaly is a common finding in β-thalassemia; however, its hemodynamic features and its potential correlations with high output state and hepatic disorders, both also frequent in thalassemia, have not yet been assessed in these patients. Eight β-thalassemia patients with the indication for splenectomy and no symptoms or signs of heart disease, aged 25.6±5.5 years, were studied. Preoperative assessment included hematological profile, liver biology, hepatitis virus serology, and echocardiography. During splenectomy, splenic artery blood flow and splenic vein pressure were directly measured and liver biopsies were taken. Preoperative echocardiographic data were compared with those of 34 healthy controls. The preoperative cardiac index was significantly elevated in patients (4.8±1.3 vs 3.4±1.1xa0l/min per m2 in controls, p<0.001). Splenic blood flow, although increased, was not particularly high, being 285±56xa0ml/min or 0.13±0.04xa0ml/min per g of splenic mass, representing 4.1±0.9% of total cardiac output (CO). Splenic vein pressure was considerably elevated (29.7±5.5xa0cmH2O). Hepatic fibrosis, iron deposition, and extramedullary foci were found in all eight biopsies. Serology was positive in five of eight cases. β-thalassemia patients with extensive splenomegaly requiring splenectomy are characterized by high output state, increased splenic blood flow, which probably makes a limited contribution to CO elevation, and portal hypertension, manifest by increased splenic vein pressure and hepatic histopathological abnormalities.


International Journal of Hematology | 2002

Detection of CD55- and/or CD59-Deficient Red Cell Populations in Patients With Plasma Cell Dyscrasias

John Meletis; Evangelos Terpos; Michalis Samarkos; Christos Meletis; Effie Apostolidou; Veroniki Komninaka; Konstantinos Korovesis; Konstantinos Anargyrou; Olga Benopoulou; Despina Mavrogianni; Eleni Variami; Nora Viniou; Konstantinos Konstantopoulos

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired clonal disorder characterized by a decrease or absence of gly-cosylphosphatidylinositol (GPI)-anchored molecules such as CD55 and CD59 from the surface of affected cells, resulting in intravascular hemolysis, cytopenia, and venous thrombosis. A PNH-like phenotype has been detected in various hematologi-cal disorders, mainly in aplastic anemia and myelodysplastic syndromes, but also in lymphoproliferative syndromes (LPSs).To the best of our knowledge, CD55- or CD59-deficient red cells have not been detected in plasma cell dyscrasias (PCDs). The aim of this study was the detection of CD55- and/or CD59-deficient red cell populations in patients with PCD. Seventy-seven patients were evaluated; 62 with multiple myeloma (MM), 7 with Waldenström macroglobulinemia (WM), 6 with monoclonal gammopathy of undetermined significance (MGUS), and 2 with heavy chain disease (HCD). The sephacryl gel microtyping system was applied; Ham and sucrose lysis tests were also performed on all samples with CD55- or CD59-negative populations. Red cells deficient in both molecules were detected in 10 (12.9%) of 77 patients with PCD: 2 (28.6%) of 7 with WM, 1 (16.6%) of 6 with MGUS, 6 (9.6%) of 62 with MM, and 1 of 2 patients with HCD. Isolated CD55 deficiency was found in 28.5% of all PCD patients, whereas isolated CD59 deficiency was not observed in any patients.These findings illustrate the existence of the PNH phenotype in the red cells of patients with PCD; further investigation is needed into the mechanisms and significance of this phenotype.


Annals of Hematology | 1990

A study of β-thromboglobulin and platelet factor-4 plasma levels in steady state sickle cell patients

S. Adamides; Konstantinos Konstantopoulos; M. Toumbis; D. Douratsos; A. Travlou; A. Kasfiki

SummaryTo evaluate the platelet function in sickle cell syndromes we measured the β-thromboglobulin (β-TG) and platelet factor 4 (PF-4) plasma values of 45 patients suffering from homozygous sickle cell anaemia (10) and sickle cell β-thalassaemia (35) in steady state. The results were compared to those of 32 normal controls. Both the β-TG and PF-4 levels were found to be significantly higher in patients than in controls but the β-TG: PF-4 ratio was significantly lower in the patients group. This finding and the absence of any statistical correlation between platelet number and β-TG or PF-4 indicate that platelets seem to be somehow activated in sickle cell syndromes, both in homozygotes and sickle cell/β-thalassaemia heterozygotes. This platelet activation seems to exist even in steady state sickle cell disease patients, regardless of the functional status of the spleen.


Haematologica | 2017

Evaluation of the Revised International Staging System (R-ISS) in an independent cohort of unselected patients with multiple myeloma

Efstathios Kastritis; Evangelos Terpos; Maria Roussou; Maria Gavriatopoulou; Magdalini Migkou; Evangelos Eleutherakis-Papaiakovou; Despoina Fotiou; Dimitrios C. Ziogas; Ioannis Panagiotidis; Eftychia Kafantari; Stavroula Giannouli; Athanasios Zomas; Konstantinos Konstantopoulos; Meletios A. Dimopoulos

The Revised International Staging System (R-ISS) was recently introduced in order to improve risk stratification over that provided by the widely used standard International Staging System. In addition to the parameters of the standard system, the R-ISS incorporates the presence of chromosomal abnormalities detected by interphase fluorescence in situ hybridization [t(4;14), t(14;16) and del17p] and elevated serum lactate dehydrogenase. The R-ISS was formulated on the basis of a large dataset of selected patients who had participated in clinical trials and has not been validated in an independent cohort of unselected patients. Thus, we evaluated the R-ISS in 475 consecutive, unselected patients, treated in a single center. Our patients were older and more often had severe renal dysfunction than those in the original publication on the R-ISS. As regards distribution by group, 18% had R-ISS-1, 64.5% R-ISS-2 and 18% R-ISS-3. According to R-ISS group, the 5-year survival rate was 77%, 53% and 19% for R-ISS-1, -2 and -3, respectively (P<0.001). The R-ISS could identify three groups with distinct outcomes among patients treated with or without autologous stem cell transplantation, among those treated with either bortezomib-based or immunomodulatory drug-based primary therapy and in patients ≤65, 66–75 or >75 years. However, in patients with severe renal dysfunction the distinction between groups was less clear. In conclusion, our data in consecutive, unselected patients, with differences in the characteristics and treatment approaches compared to the original International Myeloma Working Group cohort, verified that R-ISS is a robust tool for risk stratification of newly diagnosed patients with symptomatic myeloma.


Annals of Oncology | 2012

The International Scoring System (ISS) for multiple myeloma remains a robust prognostic tool independently of patients’ renal function

M. A. Dimopoulos; Efstathios Kastritis; Eurydiki Michalis; Costas Tsatalas; Michalis Michael; A. Pouli; Zafiris Kartasis; Sosana Delimpasi; Dimitra Gika; Athanasios Zomas; Maria Roussou; Konstantinos Konstantopoulos; A. Parcharidou; Konstantinos Zervas; Evangelos Terpos

BACKGROUNDnThe International Staging System (ISS) is the most widely used staging system for patients with multiple myeloma (MM). However, serum β2-microglobulin increases in renal impairment (RI) and there have been concerns that ISS-3 stage may include up-staged MM patients in whom elevated β2-microglobulin reflects the degree of renal dysfunction rather than tumor load.nnnPATIENTS AND METHODSnIn order to assess the impact of RI on the prognostic value of ISS, we analyzed 1516 patients with symptomatic MM and the degree of RI was classified according to the Kidney Disease Outcomes Quality Initiative-Chronic Kidney Disease (CKD) criteria.nnnRESULTSnForty-eight percent patients had stages 3-5 CKD while 29% of patients had ISS-1, 38% had ISS-2 and 33% ISS-3. The frequency and severity of RI were more common in ISS-3 patients. RI was associated with inferior survival in univariate but not in multivariate analysis. When analyzed separately, ISS-1 and ISS-2 patients with RI had inferior survival in univariate but not in multivariate analysis. In ISS-3 MM patients, RI had no prognostic impact either in univariate or multivariate analysis. Results were similar, when we analyzed only patients with Bence-Jones >200 mg/day.nnnCONCLUSIONSnISS remains unaffected by the degree of RI, even in patients with ISS-3, which includes most patients with renal dysfunction.BACKGROUNDnThe International Staging System (ISS) is the most widely used staging system for patients with multiple myeloma (MM). However, serum β2-microglobulin increases in renal impairment (RI) and there have been concerns that ISS-3 stage may include up-staged MM patients in whom elevated β2-microglobulin reflects the degree of renal dysfunction rather than tumor load.nnnPATIENTS AND METHODSnIn order to assess the impact of RI on the prognostic value of ISS, we analyzed 1516 patients with symptomatic MM and the degree of RI was classified according to the Kidney Disease Outcomes Quality Initiative-Chronic Kidney Disease (CKD) criteria.nnnRESULTSnForty-eight percent patients had stages 3-5 CKD while 29% of patients had ISS-1, 38% had ISS-2 and 33% ISS-3. The frequency and severity of RI were more common in ISS-3 patients. RI was associated with inferior survival in univariate but not in multivariate analysis. When analyzed separately, ISS-1 and ISS-2 patients with RI had inferior survival in univariate but not in multivariate analysis. In ISS-3 MM patients, RI had no prognostic impact either in univariate or multivariate analysis. Results were similar, when we analyzed only patients with Bence-Jones >200 mg/day.nnnCONCLUSIONSnISS remains unaffected by the degree of RI, even in patients with ISS-3, which includes most patients with renal dysfunction.


Annals of Hematology | 1996

Development of plasma cell tumors during treatment of multiple myeloma

George Vaiopoulos; Nora-Athina Viniou; Eleni Plata; Konstantinos Konstantopoulos; Anastasios Andreopoulos; Yannis Rombos; John Meletis; Dimitrios Loukopoulos; Xenophon Yataganas

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 α-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.

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Evangelos Terpos

National and Kapodistrian University of Athens

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John Meletis

National and Kapodistrian University of Athens

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Maria K. Angelopoulou

National and Kapodistrian University of Athens

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Theodoros P. Vassilakopoulos

National and Kapodistrian University of Athens

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George Vaiopoulos

National and Kapodistrian University of Athens

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Christos Meletis

National Technical University of Athens

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Efstathios Kastritis

National and Kapodistrian University of Athens

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Marie-Christine Kyrtsonis

National and Kapodistrian University of Athens

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Michalis Samarkos

National and Kapodistrian University of Athens

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Athanasios Zomas

National and Kapodistrian University of Athens

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