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Featured researches published by Nahide Konuk.


European Journal of Haematology | 2011

Addition of thalidomide to oral melphalan/prednisone in patients with multiple myeloma not eligible for transplantation: results of a randomized trial from the Turkish Myeloma Study Group.

Meral Beksac; Rauf Haznedar; Tulin Firatli-Tuglular; Hakan Ozdogu; Ismet Aydogdu; Nahide Konuk; Gülsan Türköz Sucak; Isik Kaygusuz; Sema Karakus; Emin Kaya; Ridvan Ali; Zafer Gulbas; Gülsüm Özet; Hakan Goker; Levent Undar

The combination of melphalan–prednisone–thalidomide (MPT) has been investigated in several clinical studies that differed significantly with regard to patient characteristics and treatment schedules. This prospective trial differs from previous melphalan–prednisone (MP) vs. MPT trials by treatment dosing, duration, routine anticoagulation, and permission for a crossover. Newly diagnosed patients with multiple myeloma (MM) (n = 122) aged greater than 55 yr, not eligible for transplantation were randomized to receive 8 cycles of M (9 mg/m2/d) and P (60 mg/m2/d) for 4 d every 6 wk (n = 62) or MP and thalidomide (100 mg/d) continuously (n = 60). Primary endpoint was treatment response and toxicities following 4 and 8 cycles of therapy. Secondary endpoints were disease‐free (DFS) and overall survival (OS). Overall, MPT‐treated patients were younger (median 69 yr vs. 72 yr; P = 0.016) and had a higher incidence of renal impairment (RI, 19% vs. 7%, respectively; P = 0.057). After 4 cycles of treatment (n = 115), there were more partial responses or better in the MPT arm than in the MP arm (57.9% vs. 37.5%; P = 0.030). However, DFS and OS were not significantly different between the arms after a median of 23 months follow‐up (median OS 26.0 vs. 28.0 months, P = 0.655; DFS 21.0 vs. 14.0 months, P = 0.342, respectively). Crossover to MPT was required in 11 patients, 57% of whom responded to treatment. A higher rate of grade 3–4 infections was observed in the MPT arm compared with the MP arm (22.4% vs. 7.0%; P = 0.033). However, none of these infections were associated with febrile neutropenia. Death within the first 3 months was observed more frequently in the MP arm (n = 8, 14.0%) than in the MPT arm (n = 2, 3.4%; P = 0.053). Long‐term discontinuation and dose reduction rates were also analyzed (MPT: 15.5% vs. MP: 5.3%; P = 0.072). Although patients treated with MPT were relatively younger and had more frequent RI, better responses and less early mortality were observed in all age groups despite more frequent discontinuation. This study is registered at http://www.clinicaltrials.gov as #NCT00934154.


British Journal of Haematology | 2002

Mobilization of peripheral blood stem cells with chemotherapy and recombinant human granulocyte colony-stimulating factor (rhG-CSF): a randomized evaluation of different doses of rhG-CSF.

Taner Demirer; Meltem Ayli; Muhit Ozcan; Nazan Günel; Rauf Haznedar; Mehmet Daglı; Turgay Fen; Yasemin Genç; Suleyman Dincer; Onder Arslan; Gunhan Gurman; S. Demirer; Gülsüm Özet; Akin Uysal; Nahide Konuk; Osman Ilhan; Haluk Koç; Hamdi Akan

Summary. To date, no randomized study has compared different doses of recombinant human granulocyte colony‐stimulating factor (rhG‐CSF) following submyeloablative mobilization chemotherapy. Therefore, we evaluated the effect of different doses of rhG‐CSF following mobilization chemotherapy on yields of CD34+ peripheral blood stem cells (PBSC). Fifty patients were randomized to receive 8 (n = 25) versus 16 µg/kg/d (n = 25) of rhG‐CSF following mobilization chemotherapy. The median number of CD34+ cells collected after 8 µg/kg/d of rhG‐CSF was 2·36 × 106/kg (range, 0·21–7·80), compared with 7·99 (2·76–14·89) after 16 µg/kg/d (P < 0·001). Twenty out of 25 (80%) patients in the low‐dose and 23 out of 25 (92%) in the high‐dose rhG‐CSF arm underwent high‐dose chemotherapy (HDC) and autologous stem cell transplantation (ASCT). Median days to white blood cell engraftment in patients mobilized with 8 µg/kg and 16 µg/kg of rhG‐CSF were 12 (10–20) and 9 (8–11) respectively (P < 0·001). There was no difference between the two groups regarding the other parameters of peritransplant morbidity: days to platelet engraftment (P = 0·10), number of red blood cell (P = 0·56) and platelet transfusions (P = 0·22), days of total parenteral nutrition requirement (P = 0·84), fever (P = 0·93) and antibiotics (P = 0·77), and number of different antibiotics used (P = 0·58). These data showed that higher doses of rhG‐CSF following submyeloablative mobilization chemotherapy were associated with a clear dose–response effect based on the collected cell yields. Based on the parameters of peritransplant morbidity, 8 µg/kg/d was as effective as 16 µg/kg/d except for a rapid neutrophil engraftment in the high‐dose arm. Therefore, in routine clinical practice, despite some advantage in the use of higher doses of rhG‐CSF, lower doses may be used for PBSC collections following chemotherapy‐based mobilization regimens in this cost‐conscious era.


Bone Marrow Transplantation | 1997

Hepatitis B virus infection in allogeneic bone marrow transplantation

C. Üstün; Haluk Koç; S Karayalçın; Gülen Akyol; Gunhan Gurman; Osman Ilhan; Hamdi Akan; Muhit Ozcan; Onder Arslan; Nahide Konuk; Akin Uysal; Meral Beksac

Fourty-four patients who underwent allogeneic bone marrow transplantation (alloBMT) were studied for hepatitis B virus (HBV)-related complications. The mean follow-up period was 15.3 months. Positivity for HBV surface antigen (HBsAg) was observed in 10 patients (22.7%) throughout the study. Four of the 10 patients were HBsAg carriers before alloBMT, while the remaining six became HBsAg(+) after alloBMT. During the follow-up period (from 6 months to 45 months), an elevation in serum ALT activity was observed in the four carriers when immunosuppression was reduced or withdrawn. All of the four HBsAg carriers developed hepatitis, but none of them died of liver failure due to HBV. Only one death due to GVHD and diabetic ketoacidosis was observed in this group. Two of the four carriers received marrow from anti-HBs positive donors and one of them cleared HBsAg from his serum via adoptive immunity 8 months after transplantation. The remaining six patients acquired HBV after alloBMT, but we were unable to demonstrate the source of HBV. Five of them had a moderate increase in serum ALT activity while the other patient had a normal ALT. Two patients seroconverted to anti-HBs spontaneously. Two patients died during the follow-up, one due to intracranial hemorrhage and the other due to GVHD and accompanying pulmonary infection. The rest of the study group (34 patients) remained HBsAg(−) throughout the study. Two of them had an HBsAg(+) donor, but neither developed HBV infection in their follow-up period. The acquisition rate of HBV infection was relatively low in recipients who were positive for anti-HBs compared to those who were negative for anti-HBs (8 vs 19%). Anti-HBs positivity remained for a longer period in recipients who received marrow from anti-HBs positive donors compared to those recipients who had anti-HBs negative donors (median 12 vs 3 months). We think that HBV is a frequent cause of liver dysfunction in alloBMT patients where HBV infection is endemic. Whether the disease is in the form of reactivation of HBsAg-positive recipients, or is acquired from unknown sources in recipients who never had contact with the virus, the course of the disease is not fatal. Silent serologic changes can be demonstrated if viral serologic markers are sought serially. Among them, the disappearance of serum anti-HBs may be important as it increases the risk of HBV contamination in recipients.


Transfusion Science | 1999

The impact of the CD34+ cell dose on engraftment in allogeneic peripheral blood stem cell transplantation.

Osman Ilhan; Onder Arslan; Mutlu Arat; Meral Beksac; Hamdi Akan; Muhit Ozcan; Gunhan Gurman; Nahide Konuk; Akin Uysal; Haluk Koç

Forty-five patients who underwent allogeneic peripheral blood stem cell transplantation (PBSCT) were evaluated in order to investigate any relationship between CD34+ cell dose given and hematological recovery. Granulocyte counts > 1.0 x 10(9)/L and platelet > 50 x 10(9)/L were considered as hematological recovery. Three different regimens were used for mobilization, by adjusting the recombinant granulocyte colony stimulating factor (rhG-CSF, Roche) dose. The first group (n = 3), whose donors mobilized with 5 micrograms/kg/d s.c. rhG-CSF received a mean of 5.9 x 10(6)/kg (95% confidence interval for mean (CI); 2.4-9.3) CD34+ cells. The second group (n = 37), mobilized with 10 micrograms/kg/d s.c. rhG-CSF and the third group (n = 5) mobilized with 15 micrograms/kg/d s.c. rhG-CSF, received a mean of 5.7 x 10(6)/kg (95% CI; 4.6-6.75) and 6.56 x 10(6)/kg (95% CI; 4.57-8.55) CD34+ cells, respectively. CD34+ cell dose was 5.82 x 10(6)/kg (95% CI; 4.97-6.68) for all the patients. All patients received rhG-CSF from day +1 until attaining granulocyte count > 1.0 x 10(9)/L for three consecutive days. Median granulocyte and platelet engraftment days for the whole group was 15 (range; 11-44) and 14 (11-54) days respectively. There was a close correlation (r = -0.301, p < 0.05) between the CD34+ cell dose and granulocyte recovery for the whole group. When these analyses were performed separately within groups, this correlation was also found significant for the first group (r = -0.99, p < 0.05) for granulocyte recovery. On the contrary the same analysis did not reach significance for the other groups, nor for platelet recovery for the whole group (r = 0.039, p = 0.821). We calculated a minimum dose of 4 x 10(6)/kg CD34+ cells for a safe alloPBSCT. There was no difference between patients who received more than 5 x 10(6)/kg CD34+ cells, and those who received more than 2 x 10(6)/kg and less than 5 x 10(6)/kg CD34+ cells. In conclusion, we have demonstrated a correlation between the CD34+ cell dose given and faster hematological recovery for alloPBSCT patients.


Bone Marrow Transplantation | 2001

Recombinant human granulocyte colony-stimulating factor (rh-G-CSF) may accelerate hematopoietic recovery after HLA-identical sibling allogeneic peripheral blood stem cell transplantation.

Muhit Ozcan; C. Üstün; E. Akcaglayan; Hamdi Akan; Onder Arslan; Osman Ilhan; Meral Beksac; Gunhan Gurman; Taner Demirer; Mutlu Arat; Harika Çelebi; Nahide Konuk; Akin Uysal; Haluk Koç

We studied the effects of recombinant human granulocyte colony-stimulating factor (G-CSF) on hematopoietic recovery and clinical outcome in patients undergoing allogeneic peripheral blood stem cell (PBSC) transplantation. Fifty-six patients with hematological malignancies who underwent allogeneic PBSC transplantation between 1995 and 1998 were entered into this study. Twenty-eight patients who received daily G-CSF from day +1 after allogeneic PBSC transplantation until the absolute neutrophil count (ANC) reached >0.5 × 109/l for 3 consecutive days were compared with 28 patients (control group) who did not receive G-CSF in a non-randomized manner. The study group and the control group were comparable with respect to baseline patient and transplantation characteristics. Median times to ANC of >0.5 × 109/l and 1 × 109/l with or without G-CSF were 12 days (range 8–21), 13 days (10–32) (P = 0.04) and 13 days (9–21), 15 days (11–44) (P = 0.02), respectively. Median times to reach a platelet count of >20 × 109/l with and without G-CSF were 11 days (0–20) and 13 days (9–26), respectively (P = 0.03). The incidence of febrile episodes was significantly lower with G-CSF, 75% vs 100% (P = 0.008). Patients receiving G-CSF had less grade III–IV mucositis than those who did not receive G-CSF (P = 0.01). There was also no increase in the incidence and severity of acute GVHD in patients using G-CSF (P = 0.22). Although the number of relapsing patients was greater in the G-CSF group (seven vs three patients), this was not statistically significant (P = 0.24). Disease-free and overall survival rates did not differ between the two groups (P = 0.58 and 0.53, respectively). The administration of G-CSF after allogeneic PBSC transplantation provided faster neutrophil and platelet engraftment associated with less severe mucositis and less febrile episodes. Bone Marrow Transplantation (2001) 27, 499–505.


Transfusion and Apheresis Science | 2001

The effect of G-CSF on lymphocyte subsets and CD34+ cells in allogeneic stem cell transplantation

Gunhan Gurman; Imdat Dilek; Onder Arslan; Mutlu Arat; Meral Beksac; Osman Ilhan; Muhit Ozcan; Hamdi Akan; Klara Dalva; Nahide Konuk; Akýn Uysal; Haluk Koç

The effect of granulocyte colony-stimulating factor (G-CSF) on peripheral blood lymphocytes (PBL) and CD34+ cell frequency in the apheresis product has been determined in 25 healthy stem cell donors. Peripheral blood mononuclear cells (PBMNC) were collected after five days of G-CSF 10 microg/kg/day s.c., which was well tolerated. The median number of leukocytes increased eight-fold over that of pretreatment levels. Collection of PBMNC lasted a median of two (range, 1-3) days. The mean mononuclear cell (MNC) count and total lymphocyte percentage were 6.69 x 10(8)/kg and 59.08%, respectively, and the frequency of CD34+ cell expression was 2.1% in the apheresis product. The frequency of CD3+, CD4+, CD25+, NK and CD122+ cell expressions in mobilized PBMNC and PBL showed no significant difference. However, the frequency of CD8+, CD8+28+, CD3+DR+, CD19+, CD20+ and CD22+ B cells expression in the apheresis product increased significantly compared to steady-state PBL. In contrast, the frequency of the CD11 a+ and CD8+38+ cell expressions in the apheresis product was decreased compared to the steady-state PBL. The mean yield of CD34+ and CD3+ cells were 13.6 x 10(6) and 2.69 x 10(8)/kg of recipient body weight (RBW), respectively. Following allograft all patients engrafted with >0.5 x 10(9)/l neutrophil and < or = 20 x 10(9)/l platelets on a median of day 13 and 12, respectively. Nine patients had grade II-IV acute GVHD and chronic GVHD occurred in eight patients. Four patients died due to transplant-related complications. There was one late engraftment failure which occurred on the fifth month. Thirteen patients are still alive. In conclusion, these results indicate that administration of G-CSF at 10 microg/kg/day in normal donors alters the lymphocyte subsets and there are significant differences in the lymphocyte contents of the recipients before apheresis and in apheresis product.


Medical Oncology | 2002

In vivo use of all-trans retinoic acid prior to induction chemotherapy improves complete remission rate and increases rhodamine 123 uptake in patients with de novo acute myeloid leukemia.

C. Üstün; Meral Beksac; Klara Dalva; Haluk Koç; Nahide Konuk; Osman Ilhan; Muhit Ozcan; Pervin Topcuoglu; D. Sertkaya; Mutlu Hayran

All-trans retinoic acid (ATRA) is used in the treatment of acute promyelocytic leukemia. Because ATRA has effects (increase in apoptosis, suppression of bcl-2), it has also been used for the treatment of other French-American-British (FAB) subtypes of acute myelogenous leukemia (AML). To find out the in vivo and in vitro effects of ATRA in AML, we analyzed 37 patients with de novo AML. Twenty-seven patients received ATRA before remission-induction (RI) treatment (ATRA group). Results were compared to a control group (10 patients) that received induction without ATRA during the same time period. Bone marrow or peripheral blood samples were collected from all patients on d 0 and 4. The immunphenotype, myeloperoxidase (MPO), reaction and the efflux uptake of rhodamine 123 (Rh123) were analyzed on myeloblasts in these samples. In the myeloblasts from patients treated with ATRA, the uptake of Rh123 was increased significantly (p=0.026) from d 0 to d 4, and all other parameters remained unaltered. ATRA administration increased the complete remission (CR) rate (88%, 22/25 vs 55%, 5/9) significantly (p=0.042). Logistic regression analysis revealed that ATRA administration was the important factor in CR, among other potential factors including age, white blood count, bcl-2 expression, and the uptake and efflux of Rh123 (p=0.05). Estimated disease-free survival and overall survival were similar between these two groups (43% vs 37.5% and 51.2% vs 37.5%, respectively). In conclusion, ATRA treatment prior to RI treatment may improve the CR rate in patients with de novo AML, which seems to be related to its beneficial effect on multidrug resistance.


Cytotherapy | 2000

Soluble adhesion molecules (sICAM-1, sL-Selectin, sE-Selectin, sCD44) in healthy allogenic peripheral stem-cell donors primed with recombinant G-CSF

Onder Arslan; Hamdi Akan; Mutlu Arat; Klara Dalva; Muhit Ozcan; Gunhan Gurman; Osman Ilhan; Nahide Konuk; Meral Beksac; Akin Uysal; Haluk Koç

BACKGROUND We analysed the effects of rhG-CSF (Amgen-Roche, USA) on serum changes of four soluble adhesion molecules (SAM) (sICAM-1, sL-Selectin, sE-Selectin and sCD44) in healthy peripheral allogeneic stem-cell transplantation donors and their correlation with acute GvHD and effect on engraftment kinetics. METHODS Serum SAM of 15 consecutive healthy HLA identical-sibling donors (median age 30 years, male:female ratio, 7:8) were monitored using a commercial ELISA Kit (Bender Med, Austria) prior to, on the day of first apheresis and 24 h after the cessation of rhG-CSF (10 microg/kg/day s.c. on 5 days) administration. Leukapheresis was started on the fifth day of rhG-CSF administration, using a continuous-flow blood separator (Cobe Spectra, COBE BCT, Inc, Lakewood, CO). Apheresis cycles were continued daily until a target of 4.0 x 10(6) CD34(+) cells/kg was reached. RESULTS The results indicate a steady rise of sL-Selectin, sE-Selectin, and sCD44, but not of sICAM-1. Median number of mononuclear cells (MNC) and CD34(+) cells transfused were 7.7x 10(8)/kg and 6.0 x 10(6)/kg, respectively. There was a near-significant correlation between the sL-Selectin levels and CD34(+) cell yield (r = 0.49, 0.06). Median granulocyte and platelet engraftment days were 11 (10-18) and 12 (9-33), respectively. There was a significant inverse correlation between the CD34(+) cell dose and granulocyte levels (r = -0.68, p = 0.022), but not for platelet engraftment. The only correlation between SAM levels and engraftment was for sICAM-1 levels. Increasing sICAM-1 levels were a sign of prolonged neutropenia (r = 0.72, p = 0.011). No correlation between the apheresis day serum levels of adhesion molecules and acute GvHD was documented. DISCUSSION Analysis of sICAM-1, sL-Selectin, sE-Selectin and sCD44 levels during allogeneic PBSC apheresis did not reveal any significant effect on engraftment and GvHD, except the correlation of sL-Selectin levels and collected CD34(+) cells. More research and data about the role of not only SAM levels, but also antigenic expression of SAM are required to enlighten leukocyte-endothelial cell interactions and egress of stem cells during G-CSF administration.


Hematological Oncology | 1998

Allogeneic peripheral blood stem cell transplantation in acute non-lymphoblastic leukemia.

Önder Arslan; Celalettin Ustun; Mutlu Arat; Harika Çelebi; Hamdi Akan; Meral Beksac; Osman Ilhan; Gunhan Gurman; Muhit Ozcan; Nahide Konuk; Akin Uysal; Haluk Koç

Unmodified allogeneic peripheral blood stem cell transplantation (alloPBSCT) was performed in 20 consecutive acute non‐lymphoblastic leukemia (ANLL) patients from their HLA‐identical siblings. There were 11 males and 9 females. Median age was 34 years (range 17–43). Donors were primed with 2·5–15 μg/kg/day s.c. granulocyte‐colony stimulating factor (G‐CSF, Neupogen, Roche). Conditioning regimen was Bu (16 mg/kg)+Cy (120 mg/kg) in 19 patients and high dose Ara‐C (3 gr/m2 twice daily for 3 days) for one patient who relapsed after bone marrow transplantation. Eighteen patients were in CR1. CsA+short‐term MTX (n=19) or CsA alone (n=1) were used for graft versus host disease (GVHD) prophylaxis. The median number of apheresis procedures for each patient was 2 (2–4). A median of 6·5 (3·2–38·2)×108/kg MNC or 9·4 (2·2–12·4)×106/kg CD34+cells were given. Median days to reach granulocyte of >0·5×109/l and platelet of >50×109/l were 12 (10–14) and 15 (11–35) respectively. Day 100 transplant‐related mortality was 20 per cent (4/20). Grade 2 to 4 AGVHD was seen in 8 out of 17 (47%) evaluable patients. Severe AGVHD occurred in 3 out of 17 (18%). Clinical CGVHD of all grades developed in 12 out of 17 (70%) evaluable patients. The mean disease‐free survival and overall survival were 17 (range: 8–33 months) and 18 months (range: 10–34 months), respectively. In conclusion, alloPBSCT in ANLL is associated with a faster engraftment, no greater incidence of AGVHD, but increased risk of CGVHD. Copyright


Medical Oncology | 1998

Randomised unicenter trial for comparison of three regimens inde novo adult acute nonlymphoblastic leukaemia

Meral Beksac; Onder Arslan; Haluk Koç; Hamdi Akan; Osman Ilhan; Mutlu Arat; Muhit Ozcan; Gunhan Gurman; Nahide Konuk; Akin Uysal

Various regimens have been explored in the treatment of acute nonlymphoblastic leukaemia (AML), but so far none has been shown to be superior. Here we report on a comparison of three widely used protocols defined by Berman (Group 1), MRC AML 10 (Group 2), and Arlin (Group 3). Group 1 includes cytosine arabinoside (Ara-C) (100 mg/m2/d, days 1–7) and idarubicin (Ida) (12 mg/m2/d, days 1–3) for induction, and Ara-C (200 mg/m2/d, days 1–6) and Ida (15 mg/m2/d, day 1) twice for consolidation. Group 2 includes Ara-C (200 mg/m2/d, days 1–10), daunorubicin (Dnc) (50 mg/m2/d, days 1, 3, 5) and etoposide (VP16) (100 mg/m2/d, days 1–5) for induction. The first consolidation therapy consisted of the same schedule except for Ara-C given on days 1–8. The second consolidation regimen consisted of Ara-C (200 mg/m2/d, days 1–8), VP16 (100 mg/m2/d, days 1–5) and amsacrine (100 mg/m2/d, days 1–5). Mitoxantrone (Mitox) (10 mg/m2/d, days 1–5) and Ara-C (200 mg/m2/d, days 1–3) were given as the third consolidation therapy. Group 3 was identical to Group 1 except for Ida being replaced with Mitox. During the study period 99 patients were enrolled and 34 were allocated randomly to Group 1, 36 to Group 2, and 29 to Group 3. Except for age distribution all patients’ characteristics were similar between the groups. As there were more elderly patients in Group 1, time to complete remission (CR) was longer in this group as they needed more second induction. Induction deaths were 9.7%, 12.9% and 14.8% in Groups 1, 2 and 3, respectively. Patients in Group 2 received a higher amount of Ara-C compared with the other groups (P<0.001). After a median follow-up period of 45 months (1–67 for survivors) an advantage in Group 1 was observed. Relapse-free survival (RFS) was better in Group 1 (P=0.014) at 3 years. Fourteen of the patients were transplanted (11 allografts, 3 autografts). When patients with transplants were excluded, overall survival was longer in Group 1 both at 3 years and 5 years (P=0.05). In conclusion, despite patient advanced age and lower dose of Ara-C, the idarubicin-containing treatment was superior to the other regimens.

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