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Dive into the research topics where Gunhan Gurman is active.

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Featured researches published by Gunhan Gurman.


Nature Reviews Clinical Oncology | 2008

Transplantation of allogeneic hematopoietic stem cells: an emerging treatment modality for solid tumors

Taner Demirer; Lisbeth Barkholt; Didier Blaise; Paolo Pedrazzoli; Massimo Aglietta; Angelo Michele Carella; Jacques-Olivier Bay; Fikret Arpaci; Giovanni Rosti; Gunhan Gurman; Dietger Niederwieser; Marco Bregni

Allogeneic transplantation of hematopoietic cells from an HLA-compatible donor has been used to treat hematologic malignancies. Allogeneic transplantation not only replaces the marrow affected by the disease, but exerts an immune graft-versus-tumor (GVT) effect mediated by donor lymphocytes. The development of nonmyeloablative conditioning regimens before allogeneic transplantation has allowed this therapy to be used in elderly and disabled patients. An allogeneic GVT effect is observed in a proportion of patients with renal, breast, colorectal, ovarian, and pancreatic cancer treated with allogeneic transplantation. In general, the tumor response is associated with the development of acute and chronic graft-versus-host disease. Further improvements will depend on the identification of the antigen targets of GVT, and on reduction of the toxicity of the procedure. Targeted therapies may complement the immune effect of allogeneic transplantation. We present updated results from the literature and data recently placed on file at the European Bone Marrow Transplantation Solid Tumors Working Party.


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.


Bone Marrow Transplantation | 1999

Autoimmune thrombocytopenia in a patient with small cell lung cancer developing after chemotherapy and resolving following autologous peripheral blood stem cell transplantation.

Taner Demirer; Harika Çelebi; Mutlu Arat; C. Üstün; S Demirer; Imdat Dilek; Muhit Ozcan; Osman Ilhan; Hamdi Akan; Gunhan Gurman; Haluk Koç

A 46-year-old white male with small cell lung cancer (SCLC) limited to the thorax developed autoimmune thrombocytopenic purpura (AITP), following a cyclophosphamide, paclitaxel and G-CSF-containing regimen for peripheral blood stem cell (PBSC) mobilization. AITP associated with small or non-small cell lung cancer has been reported. We considered that the AITP in this case may be a part of paraneoplastic syndrome, which is frequently seen in patients with SCLC. The patient received HDC and autologous PBSC transplantation (APBSCT) for SCLC and the AITP resolved following transplantation, thus supporting the concept of HDC + APBSCT for the treatment of autoimmune diseases.


Haematologica | 2015

Tyrosine kinase inhibitors improve long-term outcome of allogeneic hematopoietic stem cell transplantation for adult patients with Philadelphia chromosome positive acute lymphoblastic leukemia

Eolia Brissot; Myriam Labopin; Mariëlle M. Beckers; Gérard Socié; Alessandro Rambaldi; Liisa Volin; Jürgen Finke; Stig Lenhoff; Nicolaus Kröger; Gert J. Ossenkoppele; Charles Craddock; Ibrahim Yakoub-Agha; Gunhan Gurman; Nigel H. Russell; Mahmoud Aljurf; Michael N. Potter; Armon Nagler; Oliver G. Ottmann; Jan J. Cornelissen; Jordi Esteve; Mohamad Mohty

This study aimed to determine the impact of tyrosine kinase inhibitors given pre- and post-allogeneic stem cell transplantation on long-term outcome of patients allografted for Philadelphia chromosome-positive acute lymphoblastic leukemia. This retrospective analysis from the EBMT Acute Leukemia Working Party included 473 de novo Philadelphia chromosome-positive acute lymphoblastic leukemia patients in first complete remission who underwent an allogeneic stem cell transplantation using a human leukocyte antigen-identical sibling or human leukocyte antigen-matched unrelated donor between 2000 and 2010. Three hundred and ninety patients received tyrosine kinase inhibitors before transplant, 329 at induction and 274 at consolidation. Kaplan-Meier estimates of leukemia-free survival, overall survival, cumulative incidences of relapse incidence, and non-relapse mortality at five years were 38%, 46%, 36% and 26%, respectively. In multivariate analysis, tyrosine-kinase inhibitors given before allogeneic stem cell transplantation was associated with a better overall survival (HR=0.68; P=0.04) and was associated with lower relapse incidence (HR=0.5; P=0.01). In the post-transplant period, multivariate analysis identified prophylactic tyrosine-kinase inhibitor administration to be a significant factor for improved leukemia-free survival (HR=0.44; P=0.002) and overall survival (HR=0.42; P=0.004), and a lower relapse incidence (HR=0.40; P=0.01). Over the past decade, administration of tyrosine kinase inhibitors before allogeneic stem cell transplantation has significantly improved the long-term allogeneic stem cell transplantation outcome of adult Philadelphia chromosome-positive acute lymphoblastic leukemia. Prospective studies will be of great interest to further confirm the potential benefit of the prophylactic use of tyrosine kinase inhibitors in the post-transplant setting.


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.


Bone Marrow Transplantation | 2009

Mobilization of PBSCs with chemotherapy and recombinant human G-CSF: a randomized evaluation of early vs late administration of recombinant human G-CSF

T Ozcelik; P Topcuoglu; Meral Beksac; Muhit Ozcan; Mutlu Arat; Z Bıyıklı; S M Bakanay; Osman Ilhan; Gunhan Gurman; Onder Arslan; Taner Demirer

The optimal timing for recombinant human (rh)G-CSF administration after chemotherapy for PBSC mobilization has not yet been determined. In this study, we compared two different time schedules of rhG-CSF; 4th (early) vs 7th day (late), in 48 consecutive patients with multiple myeloma and lymphoma undergoing PBSC mobilization with CE (CY 4 g/m2 on day 1 and etoposide 200 mg/m2 on days 1–3). The rhG-CSF dose was 10 μg/kg/day for all patients. Both groups were comparable in terms of sex, age and number of previously given different chemotherapy regimens. Duration of neutropenia, CD34+ cell count on the first day of apheresis and numbers of aphereses were not statistically different between the two arms. However, the number of doses of rhG-CSF up to the first cycle of apheresis procedures was significantly lower in the late group than in the early group (P=0.005). The median number of total CD34+ cells collected was 10.54 × 106/kg (range 0.11–37.27) in the early group and 10.81 × 106/kg (range 0.17–49.83) in the late group of rhG-CSF (P=0.781). We conclude that PBSC mobilization after late use of rhG-CSF is an effective approach and therefore, in routine clinical practice, late rhG-CSF may be used for PBSC collections after chemotherapy-based mobilization regimens in this cost-conscious era.


International Journal of Dermatology | 2004

Evaluation of nail involvement in patients with chronic cutaneous graft versus host disease: a single-center study from Turkey.

Hatice Sanli; Mutlu Arat; Tuğba Oskay; Gunhan Gurman

Although graft versus host disease (GVHD) is associated with a myriad of cutaneous signs, nail involvement is rarely mentioned in the literature. This study was conducted at the Department of Dermatology and The Bone Marrow Transplantation Unit of Hematology. All patients were examined clinically for presence of nail abnormalities. Severity of nail involvement was assessed as mild or severe. Of 28 patients diagnosed with chronic cutaneous GVHD, 14 had nail manifestations. Longitudinal ridging was the most frequently observed nail change on both the fingernails and the toenails. Severe nail changes such as ptergyium and onicoatrophy were noted in a few patients. As a result we could not find any relationship between nail changes and clinical severity but there was a relationship between nail changes and duration of disease. Nail manifestations could be responsible for considerable morbidity.


Annals of Hematology | 2012

Case-matched comparison with standard versus reduced intensity conditioning regimen in chronic myeloid leukemia patients

Pervin Topcuoglu; Mutlu Arat; Muhit Ozcan; Onder Arslan; Osman Ilhan; Meral Beksac; Gunhan Gurman

This retrospective case-matched study evaluated the efficacy of reduced intensity conditioning (RIC) regimen on early and late allogeneic transplant outcome in chronic myeloid leukemia (CML) patients. Twenty-eight patients conditioned with RIC regimen were matched to 56 patients who received a myeloablative conditioning (MAC) regimen. The main criteria for case matching among our CML allotransplant cohort were the Gratwohl scoring system. The median score was 2 (1–4) in each group. The pretransplant disease status was first chronic phase (CP1, n = 20), CP2 (n = 2), and advanced phase (n = 6) in RIC, and CP1 (n = 46), CP2 (n = 3), and advanced phase (n = 7) in MAC. The duration of neutropenia and thrombocytopenia was shorter in RIC than MAC. The grade and duration of mucositis were less in RIC. The need for total parenteral nutrition (21% vs. 77%, p < 0.0001) and febrile neutropenic episodes (50% vs. 95%, p < 0.0001) were observed less frequently in RIC compared with MAC-given patients. Acute or chronic graft versus host diseases (GvHD) were not affected by the intensity of conditioning regimen. The incidence of transplant-related mortality was higher in MAC (7% vs. 14%, p = 0.01). Although more relapse/progression was observed in the RIC group, the probability of 5- and 10-year leukemia-free- and overall survival were similar regardless of conditioning regimen intensity (p > 0.05). In early first CP, the pair of female donor–male recipient and the development of chronic GvHD prolonged both leukemia-free survival and overall survival in multivariate analysis. According to our single-center matched-pair analysis, the use of RIC regimens in patients with low-risk CML results with toxicities less, responses later, and relapses more frequent than the MAC regimens.

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Mutlu Arat

Istanbul Bilim University

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