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Dive into the research topics where Dimitrios Christoulas is active.

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Featured researches published by Dimitrios Christoulas.


Annals of Oncology | 2008

Reduction of osteonecrosis of the jaw (ONJ) after implementation of preventive measures in patients with multiple myeloma treated with zoledronic acid

Meletios Athanassios Dimopoulos; E. Kastritis; Christina Bamia; Ioannis Melakopoulos; Dimitra Gika; Maria Roussou; Magdalini Migkou; E. Eleftherakis-Papaiakovou; Dimitrios Christoulas; Evangelos Terpos; Aristotle Bamias

BACKGROUND Osteonecrosis of the jaw (ONJ) is a well-described complication of bisphosphonates use in patients with multiple myeloma (MM). We investigated whether the occurrence of ONJ decreased after the implementation of preventive measures in 128 patients with MM who received zoledronic acid. PATIENTS AND METHODS Patients with MM who received zoledronic acid were included in this analysis. Patients with a previous use of other bisphosphonates were excluded; patients were stratified into group A (n=38) and group B (n=90) if treatment was started before or after the implementation of preventive measures. RESULTS One hundred and twenty-eight patients were included in this analysis. Sixteen patients (12.5%) developed ONJ--group A: 8 (26.3%), group B: 2 (6.7%) (P=0.002). The incidence rate (IR) was 0.671/100 person-months for group A and 0.230/100 person-months for group B [IR ratio 2.92, P=0.029, 95% confidence interval 1.06-8.03]. No patient in group B developed stage III ONJ. CONCLUSION In conclusion, the risk of developing ONJ after treatment of zoledronic acid is reduced (but not deleted) by the implementation of preventive measures.


Blood | 2010

The effect of prolonged administration of hydroxyurea on morbidity and mortality in adult patients with sickle cell syndromes: results of a 17-year, single-center trial (LaSHS)

Ersi Voskaridou; Dimitrios Christoulas; Antonios Bilalis; Eleni Plata; Konstantinos Varvagiannis; George Stamatopoulos; Klio Sinopoulou; Aggeliki Balassopoulou; Dimitris Loukopoulos; Evangelos Terpos

The aim of this prospective study was to evaluate the long-term efficacy and safety of hydroxyurea (HU) in patients with sickle cell disease (SCD). Thirty-four patients with sickle cell anemia (hemoglobin S [HbS]/HbS), 131 with HbS/beta(0)-thal, and 165 with HbS/beta(+)-thal participated in this trial. HU was administered to 131 patients, whereas 199 patients were conventionally treated. The median follow-up period was 8 years for HU patients and 5 years for non-HU patients. HU produced a dramatic reduction in the frequency of severe painful crises, transfusion requirements, hospital admissions, and incidence of acute chest syndrome. The probability of 10-year survival was 86% and 65% for HU and non-HU patients, respectively (P = .001), although HU patients had more severe forms of SCD. The 10-year probability of survival for HbS/HbS, HbS/beta (0)-thal, and HbS/IVSI-110 patients was 100%, 87%, and 82%, respectively, for HU patients and 10%, 54%, and 66%, for non-HU patients. The multivariate analysis showed that fetal hemoglobin values at baseline and percentage change of lactate dehydrogenase between baseline and 6 months were independently predicted for survival in the HU group. These results highlight the beneficial effect of HU, which seems to modify the natural history of SCD and raise the issue of expanding its use in all SCD patients.


Leukemia | 2009

Improved survival of patients with multiple myeloma after the introduction of novel agents and the applicability of the International Staging System (ISS): an analysis of the Greek Myeloma Study Group (GMSG).

Efstathios Kastritis; Konstantinos Zervas; Argiris Symeonidis; Evangelos Terpos; S Delimbassi; Nicolaos Anagnostopoulos; Evridiki Michali; Athanasios Zomas; E Katodritou; Dimitra Gika; Anastasia Pouli; Dimitrios Christoulas; Maria Roussou; Z Kartasis; Theofanis Economopoulos; M. A. Dimopoulos

When the novel agents thalidomide, bortezomib and lenalidomide are administered to patients with myeloma in the context of clinical trials, they are associated with a significant improvement in response, progression-free survival and in some studies, overall survival (OS); however, their effect on the outcome of unselected myeloma patients has not been fully assessed. We compared the outcome of 1376 unselected patients with symptomatic myeloma, who started treatment before or after the introduction of thalidomide. The median OS in patients who started treatment after the introduction of novel agents increased by 12 months (48 vs 36 months, P<0.001). This improvement was more pronounced in patients ⩽70 years (from 39 to 74 months, P<0.001), but less evident in patients >70 years (from 26 to 33 months, P=0.27). In patients treated after the introduction of novel agents, the international staging system (ISS) could discriminate three groups with significantly different outcomes (5-year survival for ISS stage I, II and III was 66, 45 and 18%, respectively, P<0.001). ISS was also valid in patients who actually received upfront treatment with novel drugs (4-year survival rate was 85, 61 and 26% for ISS stage I, II and III patients, P=0.001).


Leukemia | 2008

The combination of bortezomib, melphalan, dexamethasone and intermittent thalidomide is an effective regimen for relapsed/refractory myeloma and is associated with improvement of abnormal bone metabolism and angiogenesis

Evangelos Terpos; E. Kastritis; Maria Roussou; D Heath; Dimitrios Christoulas; Nicolaos Anagnostopoulos; E Eleftherakis-Papaiakovou; K Tsionos; Peter I. Croucher; M. A. Dimopoulos

This phase 2 study aimed to determine the efficacy and safety of the combination of bortezomib, melphalan, dexamethasone and intermittent thalidomide (VMDT) and its effect on bone remodeling and angiogenesis in relapsed/refractory myeloma. Bortezomib (1.0 mg/m2) was given on days 1, 4, 8, 11, oral melphalan (0.15 mg/kg) on days 1–4, whereas thalidomide (100 mg per day) and dexamethasone (12 mg/m2) were administered on days 1–4 and 17–20 of a 28-day cycle, for four cycles. Patients without disease progression continued for up to eight cycles. VMDT effect on bone remodeling was evaluated by measuring osteoclast regulators (soluble receptor activator of nuclear factor-κ B ligand/osteoprotegerin ratio, osteopontin, macrophage inflammatory protein-1α), dickkopf-1 protein, bone resorption and formation markers, whereas its effect on angiogenesis was assessed by measuring serum vascular endothelial growth factor, angiogenin, angiopoietin-2 and basic fibroblast growth factor, after four cycles and at the study end. A total of 62 patients were enrolled. The overall response rate was 66%: CR 13%, vgPR 27% and PR 26%. Median time to response was 35 days and median time to progression was 9.3 months. Common adverse events included cytopenias, peripheral neuropathy and infections. No patient experienced deep-vein thrombosis. VMDT reduced angiogenic cytokines, osteoclast regulators, dickkopf-1 and bone resorption. We conclude that VMDT with intermittent thalidomide is an active and well-tolerated regimen for relapsed/refractory myeloma, affecting abnormal bone remodeling and angiogenesis.


International Journal of Cancer | 2012

Elevated circulating sclerostin correlates with advanced disease features and abnormal bone remodeling in symptomatic myeloma: Reduction post‐bortezomib monotherapy

Evangelos Terpos; Dimitrios Christoulas; Eirini Katodritou; Cornelia Bratengeier; Maria Gkotzamanidou; Eurydiki Michalis; Sosana Delimpasi; Anastasia Pouli; John Meletis; Efstathios Kastritis; Konstantinos Zervas; Meletios A. Dimopoulos

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.


Leukemia | 2010

Treatment of patients with relapsed/refractory multiple myeloma with lenalidomide and dexamethasone with or without bortezomib: prospective evaluation of the impact of cytogenetic abnormalities and of previous therapies

M. A. Dimopoulos; E. Kastritis; Dimitrios Christoulas; Magdalini Migkou; Maria Gavriatopoulou; Maria Gkotzamanidou; Marina Iakovaki; Charis Matsouka; Despoina Mparmparoussi; Maria Roussou; E. Efstathiou; Evangelos Terpos

We prospectively studied the impact of several cytogenetic abnormalities (CAs) in patients with relapsed/refractory myeloma who received lenalidomide and dexamethasone (RD) with or without the addition of bortezomib (V). On the basis of the presence of previous neuropathy, 50 patients were treated with RD and 49, without preexisting neuropathy, with VRD. The overall response rate was 63%, similar for RD and VRD. Poor risk cytogenetics were associated with lower response rates in RD (P=0.01), but not in VRD (P=0.219). The median progression-free survival (PFS) was similar for RD (9 months) and VRD (7 months). The median overall survival (OS) for all patients was 16 months, with no differences between RD or VRD regimens. Poor risk cytogenetics, especially del17p, resistance to previous thalidomide, elevated lactate dehydrogenase (LDH) and presence of extramedullary disease were associated with inferior response to therapy and shorter PFS and OS. The impact of other CAs on OS was more pronounced in RD. In conclusion, the presence of CAs is an important adverse prognostic factor for patients with relapsed/refractory myeloma, but resistance to previous thalidomide, elevated LDH and presence of extramedullary disease remain of major prognostic importance. The outcome of patients with del17p remains extremely poor even with VRD combination.


Clinical Lymphoma, Myeloma & Leukemia | 2009

Reversibility of Renal Impairment in Patients With Multiple Myeloma Treated With Bortezomib-Based Regimens: Identification of Predictive Factors

Meletios A. Dimopoulos; Maria Roussou; Maria Gavriatopoulou; Flora Zagouri; Magdalini Migkou; Charis Matsouka; Despina Barbarousi; Dimitrios Christoulas; Erasmia Primenou; Irini Grapsa; Evangelos Terpos; Efstathios Kastritis

PURPOSE Renal impairment is a frequent complication of multiple myeloma (MM) and is associated with significant morbidity and increased early death rate. Bortezomib is active and well tolerated in patients with MM who present or develop renal impairment. PATIENTS AND METHODS We analyzed 46 consecutive patients who presented with renal impairment in order to evaluate the impact of bortezomib on the improvement of renal function and to identify predictive factors associated with renal response. All patients received bortezomib with dexamethasone with or without other agents. RESULTS Renal response was documented in 59% of patients within a median of 11 days (range, 8-41 days). Two of 9 patients who required dialysis became dialysis independent. A complete renal response (CRrenal) was documented in 30% of patients. Toxicities were similar to those seen in myeloma patients without renal failure who were treated with bortezomib-based regimens. Patients with light chain-only myeloma had a higher probability of achieving a renal response, and previously untreated patients had a higher probability for complete resolution of renal impairment, while light chain-only myeloma was independently associated with a shorter time to renal response. The degree of renal impairment was not predictive of the probability for renal response or CRrenal; however, in a subset of patients for whom cystatin C was available, a baseline cystatin C > 2 mg/L or cystatin C calculated estimated glomerular filtration rate < 30 mL/min were associated with a lower probability of CRrenal. CONCLUSION We conclude that bortezomib-based regimens may improve renal function in the majority of myeloma patients with renal impairment.


Leukemia Research | 2010

Reversibility of renal failure in newly diagnosed patients with multiple myeloma and the role of novel agents

Maria Roussou; Efstathios Kastritis; Dimitrios Christoulas; Magdalini Migkou; Maria Gavriatopoulou; Irini Grapsa; Erasmia Psimenou; Dimitra Gika; Evangelos Terpos; Meletios A. Dimopoulos

The purpose of this analysis was to assess the effect of novel agent-based regimens on the improvement of renal impairment (RI) in newly diagnosed patients with multiple myeloma. Ninety-six consecutive patients with RI received conventional chemotherapy (CC)-based regimens (n=32), IMiDs-based regimens (n=47) or bortezomib-based regimens (n=17) as frontline therapy. Improvement of RI was more frequent in patients treated with novel agents (79% in IMiD- and 94% in bortezomib-treated groups versus 59% in CC-treated group; p=0.02). Bortezomib-based regimens and CrCl>30 ml/min at baseline independently correlated with a higher probability of at least renal partial response (PRrenal) and with a shorter time to PRrenal or better. Thus bortezomib-based regimens may be the preferred treatment for newly diagnosed myeloma patients with RI.


European Journal of Haematology | 2010

Lenalidomide and dexamethasone for the treatment of refractory/relapsed multiple myeloma: Dosing of lenalidomide according to renal function and effect on renal impairment

Meletios A. Dimopoulos; Dimitrios Christoulas; Maria Roussou; Efstathios Kastritis; Magdalini Migkou; Maria Gavriatopoulou; Charis Matsouka; Despoina Mparmparoussi; Erasmia Psimenou; Irini Grapsa; Evangelos Terpos

Objectives:  Lenalidomide and dexamethasone (LenDex) is an active regimen for relapsed/refractory multiple myeloma (MM). However, there is limited data for the effect of LenDex on renal impairment (RI) and on renal reversibility.


Expert Opinion on Therapeutic Targets | 2009

Dickkopf-1: a suitable target for the management of myeloma bone disease

Maria Gavriatopoulou; Meletios-Athanasios Dimopoulos; Dimitrios Christoulas; Magdalini Migkou; Marina Iakovaki; Maria Gkotzamanidou; Evangelos Terpos

Bone disease remains a major problem in the management of patients with multiple myeloma (MM) and is characterized by the presence of lytic lesions due to increased osteoclastic activity and reduced osteoblast function. Wingless-type and integrase 1 (Wnt)/β-catenin signaling is a central pathway for bone development and homeostasis. Dickkopf-1 (Dkk-1) is a soluble inhibitor of Wnt, which disrupts osteoblast differentiation and action. Dkk-1 is produced by myeloma cells and overexpressed in myeloma microenvironment of patients with extensive bone disease. In addition to its direct inhibitory effect of Dkk-1 on osteoblasts, Dkk-1 disrupts the Wnt3a-regulated osteoprotegerin and receptor activator of NF-κB ligand (RANKL) expression in osteoblasts and thus it indirectly enhances osteoclast function in MM. Dkk-1 serum and bone marrow plasma levels are increased in MM patients and correlated with advanced International Staging System stage and presence of osteolytic lesions. Preclinical studies in mouse myeloma models showed that targeting Dkk-1 with neutralizing anti-Dkk-1 antibodies resulted in increased numbers of osteoblasts, reduced numbers of multinucleated osteoclasts and increased bone volume. The bone anabolic effect of anti-Dkk-1 may also be associated with reduced myeloma burden. These data show that Dkk-1 has a pivotal role in bone health and disease and is a novel target for the management of myeloma patients with lytic bone disease.

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Evangelos Terpos

National and Kapodistrian University of Athens

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Efstathios Kastritis

National and Kapodistrian University of Athens

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Meletios A. Dimopoulos

National and Kapodistrian University of Athens

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Maria Gavriatopoulou

National and Kapodistrian University of Athens

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Magdalini Migkou

National and Kapodistrian University of Athens

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Maria Roussou

National and Kapodistrian University of Athens

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Evangelos Eleutherakis-Papaiakovou

National and Kapodistrian University of Athens

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Maria Gkotzamanidou

National and Kapodistrian University of Athens

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Ersi Voskaridou

National and Kapodistrian University of Athens

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