Trastuzumab-based Retreatment after Lapatinib in Heavily Pretreated HER2 Positive Metastatic Breast Cancer: an Anatolian Society of Medical Oncology Study

Uncu, Dogan,Bayoglu, Ibrahim Vedat,Arslan, Ulku Yalcintas,Kucukoner, Mehmet,Artac, Mehmet,Koca, Dogan,Oguz, Arzu,Demirci, Umut,Arpaci, Erkan,Dogan, Mutlu,Kucukzeybek, Yuksel,Turker, Ibrahim,Isikdogan, Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.9

Background: For HER2 positive metastatic breast cancer (MBC), continuing anti-HER2 therapy beyond progression is associated with improved outcome. However retreatment with trastuzumab after lapatinib progression is controversial. We retrospectively analyzed the efficacy of trastuzumab-based chemotherapy in HER2+ metastatic breast cancer patients whose disease progressed after lapatinib. Materials and Methods: Between October 2010 and May 2013, 54 patients whose disease progressed after lapatinib were retreated with trastuzumab-based chemotherapy. Efficacy and toxicity results were evaluated retrospectively. Results: The median age of patients was 46 (range 27-67). Fourteen patients (26%) had metastases at the time of diagnosis. All of the patients had received trastuzumab in an adjuvant or metastatic setting, while 16 (30%) had received two lines of trastuzumab. All patients had received lapatinib plus capecitabine. The median chemotherapy line for the metastatic setting was 2 (range 1-7). Cranial metastases were identified in 27 (50%) patients. 53 patients received trastuzumab-based chemotherapy following lapatinib progression while one patient received trastuzumab monotherapy. Combination chemotherapy consisted of navelbin (n=33), taxane (n=10), gemcitabine (n=2), platinum (n=2) and platinum with taxane (n=6). The median treatment cycle was 5 (range 1-44). Among 49 patients assessed for response 2 (4%) showed CR, 12 (25%) PR, 11 (22%) SD and 24 (49%) disease progression. Asymptomatic cardiotoxicity was reported in 2 (4%) of the patients. At a median follow-up of 9 months (1-39), median progression-free survival was 5 months (95% CI 4.1-5.9) and median overall survival was 10 months (95% CI 6.9-13.0). PFS and OS were not affected by the absence/presence of cranial metastases. Conclusions: Retreatment with trastuzumab-based therapy after lapatinib progression showed efficacy in heavily treated MBC patients.

Clinicopathological Characteristics of Hepatocellular Carcinoma in Turkey

Dogan, Erkan,Yalcin, Suayib,Koca, Dogan,Olmez, Aydemir Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.6

Background: Hepatocellular carcinoma (HCC), the main malignant tumor of the liver, is very common and highly lethal. The aim of this study was to determine its clinicopathologic characteristics and risk factors in Turkey. Materials and methods: In this study, patients who were diagnosed as suffering from HCC in the period between August 2004 and December 2011 were evaluated retrospectively. Results: A total of 98 patients were included, with a median age 61 (range: 16 to 82). Seventy nine (80.6%) were male 59 (60.2%) were infected with hepatitis B virus (HBV) and 15 (15.3%) with HCV, another 15 (15.3%) being alcohol abusers. Seventy two (73.5%) were at advanced stage and 54 (55.1%) had elevated serum alpha-fetoprotein (AFP). Surgery, chemoembolization, systemic chemotherapy and application of the tyrosine kinase inhibitor sorafenib were the major treatment options. Conclusions: According to our findings HCC is mostly diagnosed in advanced stage and age, being five times more common in males than females. Main risk factors of HCC are HBV infection, HCV infection and alcohol abuse. Elevation in AFP may facilitate early diagnosis of HCC in high risk groups.

The role of serum lipoxin A4 levels in the association between periodontal disease and metabolic syndrome

Dogan, Esra Sinem Kemer,Dogan, Burak,Fentoglu, Ozlem,Kirzioglu, Fatma Yesim Korean Academy of Periodontology 2019 Journal of Periodontal & Implant Science Vol.49 No.2

Purpose: An unresolved inflammatory state contributes to the pathogenesis of periodontal disease and metabolic syndrome (MetS). Therefore, the purpose of this study was to evaluate the role of lipoxin A4 (LXA4), a proresolving lipid mediator, in the association between periodontal disease and MetS. Methods: Sixty-seven patients with MetS and 65 patients without MetS were included in the study. Sociodemographic information was obtained via a questionnaire, and detailed medical diagnoses were made. Periodontal parameters (plaque index [PI], gingival index [GI], probing pocket depth [PD], and clinical attachment level [CAL]) and metabolic parameters were measured, and serum LXA4 levels were determined. The associations among MetS, periodontal parameters, and serum LX levels were evaluated by adjusted multivariate linear regression analyses. Results: Patients with MetS were older and had a higher body mass index than patients without MetS. Periodontal parameters (PI, GI, PD, and CAL) were higher in patients with MetS than in those without MetS. Serum LXA4 levels were higher in patients without MetS. Multivariate linear regression analysis indicated a positive association between MetS and periodontal parameters (PD and CAL). Negative associations were established between MetS and LXA4 levels, and between LXA4 and periodontal parameters (PI, PD, and CAL). Conclusions: The presence of higher values of periodontal parameters in patients with MetS and the negative relationship of LXA4 with MetS and periodontal disease may support the protective role of proresolving lipid mediators in the association between periodontal disease and MetS.

Solving design optimization problems via hunting search algorithm with Levy flights

Dogan, Erkan Techno-Press 2014 Structural Engineering and Mechanics, An Int'l Jou Vol.52 No.2

This study presents a hunting search based optimum design algorithm for engineering optimization problems. Hunting search algorithm is an optimum design method inspired by group hunting of animals such as wolves, lions, and dolphins. Each of these hunters employs hunting in a different way. However, they are common in that all of them search for a prey in a group. Hunters encircle the prey and the ring of siege is tightened gradually until it is caught. Hunting search algorithm is employed for the automation of optimum design process, during which the design variables are selected for the minimum objective function value controlled by the design restrictions. Three different examples, namely welded beam, cellular beam and moment resisting steel frame are selected as numerical design problems and solved for the optimum solution. Each example differs in the following ways: Unlike welded beam design problem having continuous design variables, steel frame and cellular beam design problems include discrete design variables. Moreover, while the cellular beam is designed under the provisions of BS 5960, LRFD-AISC (Load and Resistant Factor Design-American Institute of Steel Construction) is considered for the formulation of moment resisting steel frame. Levy Flights is adapted to the simple hunting search algorithm for better search. For comparison, same design examples are also solved by using some other well-known search methods in the literature. Results reveal that hunting search shows good performance in finding optimum solutions for each design problem.

Effects of anisotropy and curvature on free vibration characteristics of laminated composite cylindrical shallow shells

Dogan, Ali,Arslan, H. Murat,Yerli, Huseyin R. Techno-Press 2010 Structural Engineering and Mechanics, An Int'l Jou Vol.35 No.4

This paper presents effects of anisotropy and curvature on free vibration characteristics of cross-ply laminated composite cylindrical shallow shells. Shallow shells have been considered for different lamination thickness, radius of curvature and elasticity ratio. First, kinematic relations of strains and deformation have been showed. Then, using Hamilton's principle, governing differential equations have been obtained for a general curved shell. In the next step, stress-strain relation for laminated, cross-ply composite shells has been given. By using some simplifications and assuming Fourier series as a displacement field, differential equations are solved by matrix algebra for shallow shells. The results obtained by this solution have been given tables and graphs. The comparisons made with the literature and finite element program (ANSYS).

Assessment of Tissue Perfusion Following Conventional Liposuction of Perforator-Based Abdominal Flaps

Dogan, Zeynep Deniz Akdeniz,Sacak, Bulent,Yalcin, Dogus,Pilanci, Ozgur,Tuncer, Fatma Betul,Celebiler, Ozhan Korean Society of Plastic and Reconstructive Surge 2017 Archives of Plastic Surgery Vol.44 No.2

Background The effect of liposuction on the perforators of the lower abdominal wall has been investigated in several studies. There are controversial results in the literature that have primarily demonstrated the number and patency of the perforators. The aim of this study was to determine the effect of liposuction on the perfusion of perforator-based abdominal flaps using a combined laser-Doppler spectrophotometer (O2C, Oxygen to See, LEA Medizintechnik). Methods Nine female patients undergoing classical abdominoplasty were included in the study. Perforators and the perfusion zones of the deep inferior epigastric artery flap were marked on the patient's abdominal wall. Flap perfusion was quantitatively assessed by measuring blood flow, velocity, capillary oxygen saturation, and relative amount of hemoglobin for each zone preoperatively, after tumescent solution infiltration, following elevation of the flap on a single perforator, and after deep and superficial liposuction, respectively. Results The measurements taken after elevation of the flap were not significantly different than measurements taken after the liposuction procedures. Conclusions The liposuction procedure does not significantly alter the perfusion of perforator-based abdominal flaps in the early period. The abdominal tissue discarded in a classic abdominoplasty operation can be raised as a perforator flap and has been demonstrated to be a unique model for clinical research.

Female Breast Cancer Mortality Rates in Turkey

Dogan, Nurhan,Toprak, Dilek Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.18

The main objective of this study was to analyze the mortality trends of female breast cancer in Turkey between the years 1987-2008. The rates per 100,000 age-standardized to the European standard population were assessed and time trends presented using joinpoint regression analysis. Average annual percent change (AAPC), anual percent change (APC) and 95% confidence interval (CI) was calculated. Nearly 23,000 breast cancer deaths occurred in Turkey during the period 1987-2008, with the average annual age-standardized mortality rate (ASR) being 11.9 per 100,000 women. In the last five years, significant increases were observed in all age groups, but there was no significant change over the age of 65. In this period, the biggest significant increase was in the 45-54 age group (AAPC=4.3, 95%CI=2.6 to 6.0).

Free vibration of an axially functionally graded pile with pinned ends embedded in Winkler-Pasternak elastic medium

Dogan Çetin,Mesut Simsek 국제구조공학회 2011 Structural Engineering and Mechanics, An Int'l Jou Vol.40 No.4

In the present study, free vibration of an axially functionally graded (AFG) pile embedded in Winkler-Pasternak elastic foundation is analyzed within the framework of the Euler-Bernoulli beam theory. The material properties of the pile vary continuously in the axial direction according to the power-law form. The frequency equation is obtained by using Lagrange’s equations. The unknown functions denoting the transverse deflections of the AFG pile is expressed in modal form. In this study, the effects of material variations, the parameters of the elastic foundation on the fundamental frequencies are examined. It is believed that the tabulated results will be a reference with which other researchers can compare their results.

Wire-guided Localization Biopsy to Determine Surgical Margin Status in Patients with Non-palpable Suspicious Breast Lesions

Dogan, Lutfi,Gulcelik, M. Ali,Yuksel, Murat,Uyar, Osman,Reis, Erhan Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.10

Purpose: Guide-wire localization (GWL) has been a standard technique for many years. Excision of nonpalpable malignant breast lesions with clear surgical margins reduces the risk of undergoing re-excision. The objective of the present study was to evaluate the efficacy of GWL biopsy for assessing surgical margins. Methods: This retrospective study concerned 53 patients who underwent GWL biopsy for non-palpable breast lesions and breast carcinoma diagnosed by histological examination. Age of the patients, tumour size, radiographic findings, breast density specifications, specimen volumes, menopausal status and family history of the patients and surgical margin status were recorded. Results: Median age was 53.3 years, median tumour size was 1.5 cm and median specimen volume was $71.5cm^3$. In fifteen patients (28%) DCIS and in 38 patients (72%) invasive ductal carcinoma was diagnosed. There was positive surgical margins in twenty eight (52.8%) patients. The median distance to the nearest surgical margin was 7.2 mm in clear surgical margins. Younger age and denser breast specifications were found as statistically significant factors for surgical margin status. Median age of the patients who had positive margins was 49.4 years where it was 56.9 years in the patients with negative margins (p=0.04). 79% of the patients with positive margins had type 3-4 pattern breast density according to BIRADS classification as compared to 48% in the patients who had negative margins (p=0.03). Some 38 patients who had positive or close surgical margins received re-excision (72%). Conclusion: Positive margin rates may be higher because of inherent biological differences and diffuse growth patterns in younger patients. There are also technical difficulties that are relevant to denser fibroglandular tissue in placing hooked wire. High re-excision rates must be taken into consideration while performing GWL biopsy in non-palpable breast lesions.

Highly Platinum-Loaded Magnéli Phase Titanium Oxides as a High Voltage Tolerant Electrocatalyst for Polymer Electrolyte Fuel Cells

Dogan, Didem C.,Hwang, Sun-Mi,Jang, Eun-Hwa,Yim, Sung-Dae,Sohn, Young-Jun,Kim, Sung-Hyun,Yang, Tae-Hyun,Park, Gu-Gon American Scientific Publishers 2015 Journal of Nanoscience and Nanotechnology Vol.15 No.9