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Dive into the research topics where Kadri Altundag is active.

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Featured researches published by Kadri Altundag.


Leukemia & Lymphoma | 2007

Rituximab-related viral infections in lymphoma patients.

Sercan Aksoy; Hakan Harputluoglu; Saadettin Kilickap; Didem S. Dede; Omer Dizdar; Kadri Altundag; Ibrahim Barista

Recently, a human/mouse chimeric monoclonal antibody, rituximab, has been successfully used to treat cases of B-cell non-Hodgkins lymphoma and some autoimmune diseases. However, several viral infections related to rituximab have been reported in the literature, but were not well characterized. To further investigate this topic, relevant English language studies were identified through Medline. There were 64 previously reported cases of serious viral infection after rituximab treatment. The median age of the cases was 61 years (range: 21 – 79). The median time period from the start of rituximab treatment to viral infection diagnosis was 5.0 months (range: 1 – 20). The most frequently experienced viral infections were hepatitis B virus (HBV) (39.1%, n = 25), cytomegalovirus infection (CMV) (23.4%, n = 15), varicella-zoster virus (VZV) (9.4%, n = 6), and others (28.1%, n = 18). Of the patients with HBV infections, 13 (52.0%) died due to hepatic failure. Among the 39 cases that had viral infections other than HBV, 13 died due to these specific infections. In this study, about 50% of the rituximab-related HBV infections resulted in death, whereas this was the case in only 33% of the cases with other infections. Close monitoring for viral infection, particularly HBV and CMV, in patients treated with rituximab should be recommended.


Cancer | 2007

Manipulating the chemokine‐chemokine receptor network to treat cancer

Pier Adelchi Ruffini; Paolo Morandi; Neslihan Cabioglu; Kadri Altundag; Massimo Cristofanilli

Chemokines are chemoattractant cytokines that regulate the trafficking and activation of leukocytes and other cell types under a variety of inflammatory and noninflammatory conditions. Over the past few years, studies have increasingly shown that chemokines play an important role in several aspects of tumor progression. Tumor cells express functional chemokine receptors, which can sustain proliferation, angiogenesis, and survival and promote organ‐specific localization of distant metastases. Chemokine expression in human malignancies is associated with a leukocyte infiltration favoring the establishment of immune escape mechanisms. A literature review of relevant publications on preclinical testing of cancer therapies based on interference with the cancer chemokine network was performed. The feasibility, potential advantages, and limitations of the clinical translation of the results of such studies in treatment of different tumor types and settings are discussed. The chemokine network is a key player in the establishment of metastases. In the preclinical setting, blocking agents and antibodies directed against CXCR4 prevent metastasis of different cancers. In mouse models, overexpression of selected chemokines causes tumor infiltration by distinct leukocyte subsets, resulting in tumor regression and tumor‐specific immunity generation. Researchers have also successfully used chemokines as carriers and/or adjuvants for cancer vaccines. The cancer chemokine network is a multifaceted therapeutic target. Cancer 2007.


European Journal of Cancer Prevention | 2008

From endometrial hyperplasia to endometrial cancer: insight into the biology and possible medical preventive measures.

Melih Cem Boruban; Kadri Altundag; Gokhan S. Kilic; Josef Blankstein

Controversies are still seen in the histological differential diagnosis of hyperplasia and well-differentiated endometrial carcinoma. Prediction of endometrial cancer in patients with hyperplasia with atypia, with the available markers has not been reliable yet. Hence these patients require more attention in the clinical management. Endometrial hyperplasia is proliferation of endometrial glands resulting in a higher gland : stroma ratio. Cytological atypia, which may progress to or co-exist with endometrial cancer and other pathological changes, result from estrogen stimulation unopposed by progesterone. Biomarkers whose expression is altered in cases of endometrial hyperplasia or cancer such as progesterone receptor, insulin-like growth factor I, retinaldehyde dehydrogenase type II, and secreted frizzled-related protein 4, seem to be promising to use as early-stage tumor markers. Mutation of PTEN is present in 83% of endometrial adenocarcinoma cases, making it the most frequent early molecular genetic alteration in type 1 endometrial tumors, which are generally associated with hyperplasia. p53 gene mutation is not found in endometrial hyperplasia, but researchers have detected this mutation in 20% of cases of endometrial carcinoma and 90% of cases of serous endometrial tumors. Cyclooxygenase-2 is important in tumorogenic transformation of hyperlasia. Expression of cyclooxygenase-2 decreases apoptosis, increases angiogenesis, and is related to invasiveness. Cyclooxygenase-2 expression increases significantly in cases of well-differentiated endometrial adenocarcinoma. Prostaglandin E2 is known to regulate aromatase gene expression and is the product of cyclooxygenase-2. The data about aromatase inhibitors are promising; in breast cancer patients, treatment with tamoxifen induces uterine abnormalities as early as 3 months after the initiation of therapy. In contrast, these abnormalities are not seen in patients who receive aromatase inhibitors and switched therapy after tamoxifen withdrawal may reverse tamoxifen-associated endometrial thickening.


Current Medical Research and Opinion | 2013

Trastuzumab emtansine (T-DM1) for HER2-positive breast cancer

Baris Boyraz; Mehmet Ali Nahit Sendur; Sercan Aksoy; Taner Babacan; Emir Charles Roach; Muhammet Cemal Kizilarslanoglu; Ibrahim Petekkaya; Kadri Altundag

Abstract Background: Trastuzumab emtansine (T-DM1), a novel drug developed for the treatment of HER2-positive breast cancer, is a human epidermal growth factor receptor (HER2) targeted antibody drug conjugate, composed of trastuzumab, a stable thioether linker, and the potent cytotoxic agent DM1 (derivative of maytansine). It has been shown that, in preclinical studies, it has anti-tumor activity in trastuzumab refractory cancer cells. In this review, we aim to show the clinical data about trastuzumab-DM1 (T-DM1) therapy and to discuss the therapy advantages for the management of patients with HER2-positive breast cancer. Scope: T-DM1 showed positive results in clinical studies of HER2-positive metastatic breast cancer. PubMed database, ASCO and San Antonio Breast Cancer Symposium Meeting abstracts were searched up to September 2012 by using the terms ‘trastuzumab emtansine (T-DM1) and anti-HER2 treatment’; papers which were considered relevant for the aim of this review were selected by the authors. Findings: The phase III randomized trial EMILIA has shown that T-DM1 provided objective tumor responses and significantly improved progression free survival and overall survival compared to lapatinib and capacitabine combination in HER2-positive metastatic breast cancer patients treated with a prior taxane and trastuzumab regimen. It is believed that T-DM1 will play a role in the management of patients with advanced and early stage HER2-positive breast cancer, but this awaits further study. In particular, the ongoing phase III trials MARIANNE and TH3RESA will further give information about the place of T-DM1 in the treatment algorithms for HER2-positive disease. Conclusion: The trials of T-DM1 as a single agent and in combination with other chemotherapies have shown clinical activity and a favorable safety profile in patients with HER2-positive metastatic breast cancer. There are ongoing studies of T-DM1 showing an increasing tendency towards moving the study of these agents to earlier stages of HER2-positive breast cancer.


Journal of Clinical Oncology | 2009

Sonographic and Electrodiagnostic Evaluations in Patients With Aromatase Inhibitor-Related Arthralgia

Omer Dizdar; Levent Özçakar; Fevziye Ünsal Malas; Hakan Harputluoglu; Nilufer Bulut; Sercan Aksoy; Yavuz Ozisik; Kadri Altundag

PURPOSE To investigate the prevalence of arthralgia in breast cancer patients taking aromatase inhibitors (AIs) and perform a detailed rheumatologic assessment including autoimmune serology, musculoskeletal sonography, and electromyography (EMG) in these patients. PATIENTS AND METHODS Postmenopausal patients with stage I to III breast cancer who were taking adjuvant AIs were enrolled (n = 92). Patients who were not receiving hormone treatment were included as a control group (n = 28). Musculoskeletal sonography and EMG were applied to the patients and the controls along with markers of autoimmunity. RESULTS Thirty patients (32.6%) reported to have AI-related new-onset or worsening arthralgia. The most commonly affected joints were knee (70%), wrist (70%), and small joints of the hand (63%). Patients taking AIs had increased tendon thicknesses compared with those who never received AIs (P < .001). Patients with AI-related arthralgia had higher rates of effusion in hand joints/tendons than those without arthralgia (P = .033). More patients with AI-related arthralgia had EMG findings consistent with carpal tunnel syndrome (CTS) than those without arthralgia (P = .024). No significant difference was observed in erythrocyte sedimentation rates, C-reactive protein, antinuclear antibody, antidouble stranded DNA antibody, rheumatoid factor, or anticyclic citrullinated peptide levels between patients and controls or between those with and without arthralgia. CONCLUSION Patients with AI-related arthralgia often show tenosynovial changes suggesting tenosynovitis, exerting local problems but lacking a systemic inflammatory component. Our finding of increased CTS frequency also supports this hypothesis.


Current Medical Research and Opinion | 2013

Cardiotoxicity of novel HER2-targeted therapies

Mehmet Ali Nahit Sendur; Sercan Aksoy; Kadri Altundag

Abstract Background: Trastuzumab, an anti-HER2 humanized monoclonal antibody, is the standard treatment for both early and metastatic HER2-positive breast cancer. In addition to other chemotherapeutic agents, trastuzumab significantly improves response rate and survival in HER2-positive early and metastatic breast cancer. Although it is well known that trastuzumab therapy is closely associated with both symptomatic and asymptomatic cardiotoxicity, less is known about novel HER2-targeted therapies. The aim of this review is to discuss the cardiac safety data from recent studies of novel anti-HER2 drugs other than trastuzumab. Scope: Novel HER2-targeted therapies showed favorable results in HER2 positive metastatic breast cancer patients. Pubmed database, ASCO and San Antonio Breast Cancer Symposium Meeting abstracts were searched until January 2013 using the following search keywords; ‘trastuzumab, trastuzumab cardiotoxicity, HER-2 targeted therapies, lapatinib, pertuzumab, trastuzumab emtansine, afatinib and neratinib’; papers which were considered relevant for the aim of this review were selected by the authors. Lapatinib, pertuzumab, T-DM1, neratinib and afatinib molecules are evaluated in the study. Findings: In a comprehensive analysis, 3689 lapatinib treated patients enrolled in 49 trials; asymptomatic cardiac events were reported in 53 patients (1.4%) and symptomatic grade III and IV systolic dysfunction was observed only in 7 patients (0.2%) treated with lapatinib. In phase I–III trials of pertuzumab, cardiac dysfunction was seen in 4.5–14.5% of patients with pertuzumab treatment and cardiac dysfunction was usually grade I and II. Cardiotoxicity of pertuzumab was usually reported with the trastuzumab combination and no additive cardiotoxicity was reported with addition of pertuzumab to trastuzumab. T-DM1 had a better safety profile compared to trastuzumab, no significant cardiotoxicity was observed with T-DM1 in heavily pre-treated patients. In the EMILIA study, only in 1.7% of patients in the T-DM1 group experienced reduction of left ventricular ejection fraction (LVEF) and grade III LVEF reduction developed only in one patient (0.2%) in the T-DM1 group compared to the lapatinib plus capacitabine group. In phase I–II trials with neratinib no cardiotoxicity was reported whereas cardiotoxicity was seen between 0–5.3% with afatinib treatment. Conclusion: Although cardiac toxicity has been reported as an adverse event for novel HER2-targeted therapies, cardiac dysfunction rate of the novel HER2-targeted therapies is significantly lower than the trastuzumab and combination of these agents with trastuzumab did not significantly increase the cardiac adverse events.


Expert Opinion on Therapeutic Targets | 2011

Variation in hormone receptor and HER-2 status between primary and metastatic breast cancer: review of the literature.

Cagatay Arslan; Ebru Sari; Sercan Aksoy; Kadri Altundag

Importance of the field: Hormone and human epidermal growth factor receptor 2 (HER-2) receptors are two important pharmaceutical targets that affect the survival of patients with metastatic breast cancer. Discordance of hormone and HER-2 receptors were reported in a series of studies. Receptor status was reported to change in both directions, yet alteration occurs mostly in the loss of positivity for both receptors. We do not know both the exact mechanism of this process or the contribution rate of technical mistakes; a number of mechanisms might be responsible. Factors suggested include: tumor heterogeneity, clonal selection of tumor cell subpopulations, genetic instability of tumor cells, local or systemic treatments, the time interval between primary tumor and metastasis, receptor status determination techniques, and the site of metastasis. Areas covered in this review: Studies of estrogen, progesterone and HER-2 receptor discordance between primary and metastasis of breast cancer are summarized. Laboratory evaluation of estrogen, progesterone and HER-2 receptors, and possible causes of receptor discordance, are summarized. Literature data are reviewed; the major shortcoming of these studies is that they are mostly retrospective. What the reader will gain: The reader will read a concise literature review about the studies on estrogen, progesterone and HER-2 receptor discordances between primary and metastasis of breast cancer. Take home message: We do not know whether the changes in receptor expression account for a true biological phenomenon or may result from inconsistent measurement. However, in light of current data, for the treatment plans that target the receptors, biopsy specimen from the metastatis of breast cancer must also be evaulated for alterations in the receptor status.


The Breast | 2011

Breast cancer subtypes and outcomes of central nervous system metastases

Ulku Yalcintas Arslan; Berna Oksuzoglu; Sercan Aksoy; Hakan Harputluoglu; Ibrahim Turker; Yavuz Ozisik; Omer Dizdar; Kadri Altundag; Necati Alkis; Nurullah Zengin

Central nervous system (CNS) metastases are detected in up to one third of patients with advanced breast cancer, but their incidence and outcomes by breast cancer subtypes are not precisely documented. Herein, we retrospectively analyzed clinicopathologic data of 259 breast cancer patients with CNS metastases to evaluate the association between breast cancer subtypes and CNS metastasis. The patient groups were classified according to their hormone receptor status and HER-2 expression. Median follow-up time among the patients was 42 months and median survival after CNS metastasis detection was 7.8 months. In HER-2 overexpressing group, median time period between the diagnosis of breast cancer and the detection of CNS metastasis (15.9 months) was significantly shorter compared to the other groups (p = 0.01). The triple negative group had the shortest median survival time after CNS metastasis (6.6 months), although statistically not significant (p = 0.3). In multivariate Cox regression analyses, having solitary CNS metastasis (HR 0.4, 95% CI; 0.2-0.7, p = 0.004), and receiving chemotherapy after CNS metastasis (HR 0.4, 95% CI; 0.287-0.772, p = 0.003) were independent prognostic factors for increasing survival after CNS metastasis. In conclusion, new and effective treatment strategies are required for breast carcinoma patients with brain metastasis considering the positive effect of the treatment on survival.


Cancer Genetics and Cytogenetics | 2010

EGFR expression and gene copy number in triple-negative breast carcinoma

Berrak Gumuskaya; Murat Alper; Sema Hucumenoglu; Kadri Altundag; Aysegul Uner; Gulnur Guler

Most basal-like breast carcinomas are estrogen receptor negative, progesterone receptor negative, and cerb-B2/HER-2/neu negative--the so-called triple-negative breast carcinomas--with high epidermal growth factor receptor (EGFR) expression, which makes EGFR a target of treatment. We evaluated EGFR expression by immunohistochemistry (IHC) with two different clones (EGFR.31G7 and EGFR.25) and gene copy number by fluorescence in situ hybridization (FISH) with Locus specific identifier EGFR/CEP 7 dual probe in 62 triple-negative breast carcinomas. Any complete or incomplete membranous and/or cytoplasmic expression was regarded as IHC positive. Cases showing gene amplification (a ratio of EGFR gene to chromosome 7 of ≥ 2 or 15 copies per cell in ≥ 10% of cells) and high polysomy (≥ 4 copies in ≥ 40% of cells) were considered FISH po sitive. We detected EGFR.31G7 positivity in 38 of 62 cases (61.4%), which was composed of 12 of 62 (19.4%) cytoplasmic, 14 of 62 (22.6%) incomplete membranous, and 12 of 62 (19.4%) complete membranous staining. Among 38 of 49 (77.6%) EGFR.25-positive cases, 7 of 49 (14.3%) exhibited cytoplasmic, 10 of 49 (20.4%) exhibited incomplete membranous, and 21 of 49 (42.9%) exhibited complete membranous staining pattern. Ten of 62 (16.1%) FISH-positive cases were identified; 1 of 62 (1.6%) showed amplification, and the rest showed high polysomy. All FISH-positive cases were also found to be IHC positive (P = 0.01) by both EGFR clones. The amplified case displayed strong complete membranous staining with both clones. Among the high polysomic cases; 4 of 9 (44.4%) incomplete membranous, 4 of 9 (44.4%) complete membranous and 1 of 9 (11.1%) cytoplasmic expression of EGFR.31G7, and 6 of 8 (75%) complete membranous and 2 of 6 (25%) cytoplasmic expression of EGFR.25 were detected. Here, we report that membranous EGFR expression is associated with increased gene copy number (P = 0.035 for EGFR.31G7 and P = 0.026 for EGFR.25 clone). Because the markers to predict anti-EGFR treatment response in other system tumors such as EGFR mutation and amplification seem to be rare events in breast cancer, membranous staining pattern of EGFR might be the best way to decide the patient eligibility for anti-EGFR therapy.


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2005

Induction chemotherapy with cisplatin and 5-fluorouracil followed by chemoradiotherapy or radiotherapy alone in the treatment of locoregionally advanced resectable cancers of the larynx and hypopharynx: Results of single-center study of 45 patients

Ozden Altundag; Ibrahim Gullu; Kadri Altundag; Suayib Yalcin; Enis Özyar; Mustafa Cengiz; Fadil Akyol; Taşkın Yücel; Sefik Hosal; Bülent Sözeri

Induction chemotherapy with cisplatin and fluorouracil and radiotherapy is an effective alternative to surgery in patients with carcinoma of the larynx and hypopharynx who are treated for organ preservation.

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Mehmet Ali Nahit Sendur

Yıldırım Beyazıt University

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Nuriye Ozdemir

Yıldırım Beyazıt University

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