Turkiye Klinikleri Journal of Biostatistics

.: ORIGINAL RESEARCH
The Classification Capability of Urine Biomarkers in the Diagnosis of Pancreatic Cancer with Logistic Regression Based on Regularized Approaches: A Methodological Research
Pankreas Kanseri Teşhisinde İdrar Biyobelirteçlerinin Düzenlileştirme Yaklaşımlarına Dayalı Lojistik Regresyonla Sınıflandırma Kabiliyeti: Metodolojik Çalışma
Özlem ALPUa, Güven PEKDEMİRa
aDepartment of Statistics, Eskişehir Osmangazi University Faculty of Science and Letters, Eskişehir, Türkiye
Turkiye Klinikleri J Biostat. 2022;14(2):118-28
doi: 10.5336/biostatic.2022-90697
Article Language: EN
Full Text
ABSTRACT
 Objective: This study aims to compare the accuracy, reliability, and validity levels of the techniques by using various performance measures applying logistic regression models based on regularization approaches from data mining classification techniques on a dataset. Material and Methods: With the development of computerization and technology, machine learning is used in many fields as well as in the field of medicine. It has grown in popularity, particularly in cancer diagnosis. A urine biomarkers dataset from the public platform Kaggle database, which is freely available to all researchers, was used to reveal the most appropriate model for diagnosing patients' pancreatic ductal adenocarcinoma (PDAC). Because of the multicollinearity, the following regression models were considered to classify the disease diagnosis: Logistic lasso, logistic ridge, logistic elastic net, logistic adaptive lasso, logistic adaptive elastic net, and logistic adaptive group lasso. The classification success of the methods used was compared using reliability and validity criteria. Results: There were three statistically significant variables in all logistic regularization models, according to PDAC diagnostic results. Compared to the estimated model results, the logistic adaptive group lasso regression model appears to perform better in PDAC diagnosis. In addition to the three variables in this model, the variables age and plasma CA19-19 have been identified as important variables in PDAC diagnosis. Conclusion: As a result of comparative analyses, the logistic adaptive group lasso regression model outperformed the others in terms of performance measures.

Keywords: Logistic regression; regularization methods; lasso; adaptive group lasso
ÖZET
 Amaç: Bu çalışma, veri madenciliği sınıflandırma tekniklerinden düzenlileştirme yaklaşımlarına dayalı lojistik regresyon modellerini bir veri kümesi üzerinde uygulayarak tekniklerin doğruluk, güvenirlik ve geçerlilik düzeylerini çeşitli performans ölçüleri aracılığıyla karşılaştırmayı amaçlamaktadır. Gereç ve Yöntemler: Makineleşmenin ve teknolojinin gelişmesiyle makine öğrenmesi tıp alanında olduğu gibi birçok alanda kullanılmaktadır. Özellikle kanser teşhisi konusunda artan bir kullanıma sahiptir. Çalışmada pankreatik duktal adenokarsinomunu (PDAC) teşhis etmede en uygun modeli ortaya çıkarmak amacıyla tüm araştırmacıların kullanımına ve erişimine açık olarak sunulan Kaggle veri tabanından bir idrar biyobelirteçleri veri kümesi kullanıldı. Veri kümesindeki değişkenler arasında çoklu doğrusal bağıntı problemi olması nedeniyle, hastalık teşhisini sınıflandırmada lojistik lasso, lojistik ridge, lojistik elastik ağ, lojistik uyarlamalı lasso, lojistik uyarlamalı elastik ağ ve lojistik uyarlamalı grup lasso regresyon modelleri ele alınmıştır. Kullanılan modeller sınıflandırma başarısı, güvenirlik ve geçerlik kriterleri kullanılarak karşılaştırılmıştır. Bulgular: Tüm düzenlileştirme tahmin modellerindeki PDAC teşhisi sonuçlarına göre istatistiksel olarak anlamlı bulunan üç değişken belirlenmiştir. Tahmin edilen model sonuçları karşılaştırıldığında, PDAC teşhisinde lojistik uyarlamalı grup lasso regresyon modelinin daha iyi sonuç verdiği görülmektedir. Bu modelde tüm modellerde anlamlı bulunan değişkenlere ilave olarak yaş ve plazma CA19-19 değişkenlerinin de önemli değişkenler olarak belirlendiği görülmektedir. Sonuç: Karşılaştırmalı analizler sonucunda performans ölçülerine göre lojistik uyarlamalı grup lasso regresyon modelinin en iyi performansı gösterdiği gözlenmiştir.

Anahtar Kelimeler: Lojistik regresyon; düzenlileştirme yöntemleri; lasso; uyarlamalı grup lasso
REFERENCES:
  1. Sung H, Ferlay J, Siegel RL, Laversanne M, Soerjomataram I, Jemal A, et al. Global Cancer Statistics 2020: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries. CA Cancer J Clin. 2021;71(3):209-49. [Crossref]  [PubMed] 
  2. Mayerle J, Kalthoff H, Reszka R, Kamlage B, Peter E, Schniewind B, et al. Metabolic biomarker signature to differentiate pancreatic ductal adenocarcinoma from chronic pancreatitis. Gut. 2018;67(1):128-37. Erratum in: Gut. 2018;67(5):994. [Crossref]  [PubMed]  [PMC] 
  3. Debernardi S, O'Brien H, Algahmdi AS, Malats N, Stewart GD, Plje?a-Ercegovac M, et al. A combination of urinary biomarker panel and PancRISK score for earlier detection of pancreatic cancer: a case-control study. PLoS Med. 2020;17(12):e1003489. [Crossref]  [PubMed]  [PMC] 
  4. Shimizu Y, Yasui K, Matsueda K, Yanagisawa A, Yamao K. Small carcinoma of the pancreas is curable: new computed tomography finding, pathological study and postoperative results from a single institute. J Gastroenterol Hepatol. 2005;20(10):1591-4. [Crossref]  [PubMed] 
  5. Sarantis P, Koustas E, Papadimitropoulou A, Papavassiliou AG, Karamouzis MV. Pancreatic ductal adenocarcinoma: treatment hurdles, tumor microenvironment and immunotherapy. World J Gastrointest Oncol. 2020;12(2):173-81. [Crossref]  [PubMed]  [PMC] 
  6. Sanoob M, Madhu A, Ajesh K, Varghese SM. Artificial neural network for diagnosis of pancreatic cancer. Int J Cybernet Inform. 2016;5:41-9. [Crossref] 
  7. Blyuss O, Zaikin A, Cherepanova V, Munblit D, Kiseleva EM, Prytomanova OM, et al. Development of PancRISK, a urine biomarker-based risk score for stratified screening of pancreatic cancer patients. Br J Cancer. 2020;122(5):692-6. [Crossref]  [PubMed]  [PMC] 
  8. Ge G, Wong GW. Classification of premalignant pancreatic cancer mass-spectrometry data using decision tree ensembles. BMC Bioinformatics. 2008;9:275. [Crossref]  [PubMed]  [PMC] 
  9. Marengo E, Robotti E, Cecconi D, Scarpa A, Righetti PG. Application of fuzzy logic principles to the classification of 2D-PAGE maps belonging to human pancreatic cancers treated with Trichostatin-A. 2004 IEEE International Conference on Fuzzy Systems (IEEE Cat. No.04CH37542). 2004;1:359-64. [Link] 
  10. Torshabi AE, Riboldi M, Pella A, Negarestani A, Rahnema M, Baroni G. A clinical application of fuzzy logic. In: Dadios EP, ed. Emerging Technologies and Applications. 1st ed. Rijeka, Croatia: InTech; 2012. p.3-18. ISBN:978-953-51-0337-0 [Crossref]  [PubMed] 
  11. Jiang W, Shen Y, Ding Y, Ye C, Zheng Y, Zhao P, et al. A naive Bayes algorithm for tissue origin diagnosis (TOD-Bayes) of synchronous multifocal tumors in the hepatobiliary and pancreatic system. Int J Cancer. 2018;142(2):357-68. Erratum in: Int J Cancer. 2018;143(1):E2. [Crossref]  [PubMed] 
  12. Sadewo W, Rustam Z, Hamidah H, Chusmarsyah AR. Pancreatic cancer early detection using twin support vector machine based on kernel. Symmetry. 2020;12(4):667. [Crossref] 
  13. Chang C-L, Hsu M-Y. The study that applies artificial intelligence and logistic regression for assistance in differential diagnostic of pancreatic cancer, Expert Systems with Applications. 2009;36(7):10663-72. [Crossref] 
  14. Baecker A, Kim S, Risch HA, Nuckols TK, Wu BU, Hendifar AE, et al. Do changes in health reveal the possibility of undiagnosed pancreatic cancer? Development of a risk-prediction model based on healthcare claims data. PLoS One. 2019;14(6):e0218580. [Crossref]  [PubMed]  [PMC] 
  15. Appelbaum L, Cambronero JP, Stevens JP, Horng S, Pollick K, Silva G, et al. Development and validation of a pancreatic cancer risk model for the general population using electronic health records: an observational study. Eur J Cancer. 2021;143:19-30. [Crossref]  [PubMed] 
  16. Hsieh MH, Sun LM, Lin CL, Hsieh MJ, Hsu CY, Kao CH. Development of a prediction model for pancreatic cancer in patients with type 2 diabetes using logistic regression and artificial neural network models. Cancer Manag Res. 2018;10:6317-24. [Crossref]  [PubMed]  [PMC] 
  17. Lee HA, Chen KW, Hsu CY. Prediction model for pancreatic cancer-a population-based study from NHIRD. Cancers (Basel). 2022;14(4):882. [Crossref]  [PubMed]  [PMC] 
  18. Cho S-B, Won H-H. Machine learning in DNA microarray analysis for cancer classification. Proceedings of the First Asia-Pacific Bioinformatics Conference. 2003;34:189-98.
  19. Hoerl A, Kennard R. Ridge regression: biased estimation for nonorthogonal problems. Technometrics. 1970;12:55-67. [Crossref] 
  20. Schaefer RL, Roi LD, Wolfe RA. A ridge logistic estimator. Communications in Statistics: Theory and Methods. 1984;3:99-113. [Crossref] 
  21. Çiftsüren MN, Akkol S. Prediction of internal egg quality characteristics and variable selection using regularization methods: ridge, lasso and elastic net. Archives Animal Breeding. 2018;61(3):279-84. [Crossref] 
  22. Tibshirani R. Regression shrinkage and selection via the lasso. Journal of the Royal Statistical Society. Series B (Methodological). 1996;58(1):267-88. [Crossref] 
  23. Zou H, Hastie T. Regularization and variable selection via the elastic net. Journal of the Royal Statistical Society: Series B (Statistical Methodology). 2005;67:301-20. [Crossref] 
  24. Friedman J, Hastie T, Tibshirani R. Regularization paths for generalized linear models via coordinate descent. J Stat Softw. 2010;33(1):1-22. [Crossref]  [PubMed]  [PMC] 
  25. Zou H. The adaptive lasso and its oracle properties. Journal of the American Statistical Association. 2006;101(476):1418-29. [Crossref] 
  26. Algamal ZY, Lee MH. Regularized logistic regression with adjusted adaptive elastic net for gene selection in high dimensional cancer classification. Comput Biol Med. 2015;67:136-45. [Crossref]  [PubMed] 
  27. Zou H, Zhang HH. On the adaptive elastic-net with a diverging number of parameters. Annals of Statistics. 2009;37(4):1733-51. [Crossref]  [PubMed]  [PMC] 
  28. Ghosh S. On the grouped selection and model complexity of the adaptive elastic net. Stat Comput. 2011;21:451-62. [Crossref] 
  29. Wang H, Leng C. A note on adaptive group lasso. Computational Statistics and Data Analysis. 2008;52(12):5277-86. [Crossref] 
  30. Yuan M, Lin Y. Model selection and estimation in regression with grouped variables. Journal of the Royal Statistical Society: Series B (Statistical Methodology). 2006;68(1):49-67. [Crossref] 
  31. Yang X, Tong Y, Meng X, Zhao S, Xu Z, Li Y, et al. Adaptive logistic group Lasso method for predicting the no-reflow among the multiple types of high-dimensional variables with missing data. 7th IEEE International Conference on Software Engineering and Service Science (ICSESS). 2016;1085-9. [Crossref] 
  32. RStudio [Internet]. Copyright © 2022 RStudio, PBC [Accessing Date:19.04.2022]. Available from: [Link] 
  33. van Buuren S, Groothuis-Oudshoorn K. mice: Multivariate Imputation by Chained Equations in R. Journal of Statistical Software. 2011;45(3):1-67. [Crossref] 
  34. Gonzalez Estrada E, Villasenor-Alva JA. mvShapiroTest: Generalized Shapiro Wilk test for multivariate normality. R package version 1.0. 2013.

.: Up To Date

.: Process List

Login

 Forgot your password?

 New Registration  

Contact

Ortadoğu Reklam Tanıtım Yayıncılık Turizm Eğitim İnşaat Sanayi ve Ticaret A.Ş.

.: Address

Turkocagi Caddesi No:30 06520 Balgat / ANKARA
Phone: +90 312 286 56 56
Fax: +90 312 220 04 70
E-mail: info@turkiyeklinikleri.com

.: Manuscript Editing Department

Phone: +90 312 286 56 56/ 2
E-mail: yaziisleri@turkiyeklinikleri.com

.: English Language Redaction

Phone: +90 312 286 56 56/ 145
E-mail: tkyayindestek@turkiyeklinikleri.com

.: Marketing Sales-Project Department

Phone: +90 312 286 56 56/ 142
E-mail: reklam@turkiyeklinikleri.com

.: Subscription and Public Relations Department

Phone: +90 312 286 56 56/ 118
E-mail: abone@turkiyeklinikleri.com

.: Customer Services

Phone: +90 312 286 56 56/ 118
E-mail: satisdestek@turkiyeklinikleri.com

1. TERMS OF USE

1.1. To use the web pages with http://www.turkiyeklinikleri.com domain name or the websites reached through the sub domain names attached to the domain name (They will be collectively referred as "SITE"), please read the conditions below. If you do not accept these terms, please cease to use the "SITE." "SITE" owner reserves the right to change the information on the website, forms, contents, the "SITE," "SITE" terms of use anytime they want.

1.2. The owner of the "SITE" is Ortadoğu Advertisement Presentation Publishing Tourism Education Architecture Industry and Trade Inc. (From now on it is going to be referred as "Turkiye Klinikleri", shortly) and it resides at Turkocagi cad. No:30, 06520 Balgat Ankara. The services in the "SITE" are provided by "Turkiye Klinikleri."

1.3. Anyone accessing the "SITE" with or without a fee whether they are a natural person or a legal identity is considered to agree these terms of use. In this contract hereby, "Turkiye Klinikleri" may change the stated terms anytime. These changes will be published in the "SITE" periodically and they will be valid when they are published. Any natural person or legal identity benefiting from and reaching to the "SITE" are considered to be agreed to any change on hereby contract terms done by "Turkiye Klinikleri."

1.4. The "Terms of Use" hereby is published in the website with the last change on March 30th 2014 and the "SITE" is activated by enabling the access to everyone. The "Terms of Use" hereby is also a part of the any "USER Contract" was and/or will be done with the users using "Turkiye Klinikleri" services with or without a fee an inseparable.

2. DEFINITIONS

2.1. "SITE": A website offering different kind of services and context with a certain frame determined by "Turkiye Klinikleri" and it is accessible on-line on http://www.turkiyeklinikleri.com domain name and/or subdomains connected to the domain name.

2.2. USER: A natural person or a legal identity accessing to the "SITE" through online settings.

2.3. LINK: A link enabling to access to another website through the "SITE", the files, the context or through another website to the "SITE", the files and the context.

2.4. CONTEXT: Any visual, literary and auditory images published in the "Turkiye Klinikleri", "SITE" and/or any website or any accessible information, file, picture, number/figures, price, etc.

2.5. "USER CONTRACT": An electronically signed contract between a natural or a legal identity benefiting from special services "Turkiye Klinikleri" will provide and "Turkiye Klinikleri".

3. SCOPE OF THE SERVICES

3.1. "Turkiye Klinikleri" is completely free to determine the scope and quality of the services via the "SITE".

3.2. To benefit the services of "Turkiye Klinikleri" "SITE", the "USER" must deliver the features that will be specified by "Turkiye Klinikleri". "Turkiye Klinikleri" may change this necessity any time single-sided.

3.3. Not for a limited number, the services "Turkiye Klinikleri" will provide through the "SITE" for a certain price or for free are;

- Providing scientific articles, books and informative publications for health industry.

- Providing structural, statistical and editorial support to article preparation stage for scientific journals.

4. GENERAL PROVISIONS

4.1. "Turkiye Klinikleri" is completely free to determine which of the services and contents provided in the "SITE" will be charged.

4.2. People benefiting from the services provided by "Turkiye Klinikleri" and using the website can use the "SITE" only according to the law and only for personal reasons. Users have the criminal and civil liability for every process and action they take in the "SITE". Every USER agrees, declares and undertakes that they will not proceed by any function or action infringement of rights of "Turkiye Klinikleri"s and/or other third parties', they are the exclusive right holder on usage, processing, storage, made public and revealing any written, visual or auditory information reported to Turkiye Klinikleri" and/or "SITE" to the third parties. "USER" agrees and undertakes that s/he will not duplicate, copy, distribute, process, the pictures, text, visual and auditory images, video clips, files, databases, catalogs and lists within the "SITE", s/he will not be using these actions or with other ways to compete with "Turkiye Klinikleri", directly or indirectly.

4.3. The services provided and the context published within the "SITE" by third parties is not under the responsibility of "Turkiye Klinikleri", institutions collaborated with "Turkiye Klinikleri", "Turkiye Klinikleri" employee and directors, "Turkiye Klinikleri" authorized salespeople. Commitment to accuracy and legality of the published information, context, visual and auditory images provided by any third party are under the full responsibility of the third party. "Turkiye Klinikleri" does not promise and guarantee the safety, accuracy and legality of the services and context provided by a third party.

4.4. "USER"s cannot act against "Turkiye Klinikleri", other "USER"s and third parties by using the "SITE". "Turkiye Klinikleri" has no direct and/or indirect responsibility for any damage a third party suffered or will suffer regarding "USER"s actions on the "SITE" against the rules of the hereby "Terms of Use" and the law.

4.5. "USER"s accept and undertake that the information and context they provided to the "SITE" are accurate and legal. "Turkiye Klinikleri" is not liable and responsible for promising and guaranteeing the verification of the information and context transmitted to "Turkiye Klinikleri" by the "USER"s, or uploaded, changed and provided through the "SITE" by them and whether these information are safe, accurate and legal.

4.6. "USER"s agree and undertake that they will not perform any action leading to unfair competition, weakening the personal and commercial credit of "Turkiye Klinikleri" and a third party,  encroaching and attacking on personal rights within the "SITE" in accordance with the Turkish Commercial Code Law.

4.7. "Turkiye Klinikleri" reserves the right to change the services and the context within the "SITE"  anytime. "Turkiye Klinikleri" may use this right without any notification and timelessly. "USER"s have to make the changes and/or corrections "Turkiye Klinikleri" required immediately. Any changes and/or corrections that are required by "Turkiye Klinikleri", may be made by "Turkiye Klinikleri" when needed. Any harm, criminal and civil liability resulted or will result from changes and/or corrections required by "Turkiye Klinikleri" and were not made on time by the "USER"s belongs completely to the users.

4.8. "Turkiye Klinikleri" may give links through the "SITE" to other websites and/or "CONTEXT"s and/or folders that are outside of their control and owned and run by third parties. These links are provided for ease of reference only and do not hold qualification for support the respective web SITE or the admin or declaration or guarantee for the information inside. "Turkiye Klinikleri" does not hold any responsibility over the web-sites connected through the links on the "SITE", folders and context, the services or products on the websites provided through these links or their context.

4.9. "Turkiye Klinikleri" may use the information provided to them by the "USERS" through the "SITE" in line with the terms of the "PRIVACY POLICY" and "USER CONTRACT". It may process the information or classify and save them on a database. "Turkiye Klinikleri" may also use the USER's or visitor's identity, address, e-mail address, phone number, IP number, which sections of the "SITE" they visited, domain type, browser type, date and time information to provide statistical evaluation and customized services.

5. PROPRIETARY RIGHTS

5.1. The information accessed through this "SITE" or provided by the users legally and all the elements (including but not limited to design, text, image, html code and other codes) of the "SITE" (all of them will be called as studies tied to "Turkiye Klinikleri"s copyrights) belongs to "Turkiye Klinikleri". Users do not have the right to resell, process, share, distribute, display or give someone permission to access or to use the "Turkiye Klinikleri" services, "Turkiye Klinikleri" information and the products under copyright protection by "Turkiye Klinikleri". Within hereby "Terms of Use" unless explicitly permitted by "Turkiye Klinikleri" nobody can reproduce, process, distribute or produce or prepare any study from those under "Turkiye Klinikleri" copyright protection.

5.2. Within hereby "Terms of Use", "Turkiye Klinikleri" reserves the rights for "Turkiye Klinikleri" services, "Turkiye Klinikleri" information, the products associated with "Turkiye Klinikleri" copyrights, "Turkiye Klinikleri" trademarks, "Turkiye Klinikleri" trade looks or its all rights for other entity and information it has through this website unless it is explicitly authorized by "Turkiye Klinikleri".

6. CHANGES IN THE TERMS OF USE

"Turkiye Klinikleri" in its sole discretion may change the hereby "Terms of Use" anytime announcing within the "SITE". The changed terms of the hereby "Terms of Use" will become valid when they are announced. Hereby "Terms of Use" cannot be changed by unilateral declarations of users.

7. FORCE MAJEURE

"Turkiye Klinikleri" is not responsible for executing late or never of this hereby "Terms of Use", privacy policy and "USER Contract" in any situation legally taken into account as force majeure. Being late or failure of performance or non-defaulting of this and similar cases like this will not be the case from the viewpoint of "Turkiye Klinikleri", and "Turkiye Klinikleri" will not have any damage liability for these situations. "Force majeure" term will be regarded as outside of the concerned party's reasonable control and any situation that "Turkiye Klinikleri" cannot prevent even though it shows due diligence. Also, force majeure situations include but not limited to natural disasters, rebellion, war, strike, communication problems, infrastructure and internet failure, power cut and bad weather conditions.

8. LAW AND AUTHORISATION TO FOLLOW

Turkish Law will be applied in practicing, interpreting the hereby "Terms of Use" and managing the emerging legal relationships within this "Terms of Use" in case of finding element of foreignness, except for the rules of Turkish conflict of laws. Ankara Courts and Enforcement Offices are entitled in any controversy happened or may happen due to hereby contract.

9. CLOSING AND AGREEMENT

Hereby "Terms of Use" come into force when announced in the "SITE" by "Turkiye Klinikleri". The users are regarded to agree to hereby contract terms by using the "SITE". "Turkiye Klinikleri" may change the contract terms and the changes will be come into force by specifying the version number and the date of change on time it is published in the "SITE".

 

30.03.2014

Privacy Policy

We recommend you to read the terms of use below before you visit our website. In case you agree these terms, following our rules will be to your favor. Please read our Terms of Use thoroughly.

www.turkiyeklinikleri.com website belongs to Ortadoğu Advertisement Presentation Publishing Tourism Education Architecture Industry and Trade Inc. and is designed in order to inform physicians in the field of health

www.turkiyeklinikleri.com cannot reach to user’s identity, address, service providers or other information. The users may send this information to the website through forms if they would like to. However, www.turkiyeklinikleri.com may collect your hardware and software information. The information consists of your IP address, browser type, operating system, domain name, access time, and related websites. www.turkiyeklinikleri.com cannot sell the provided user information (your name, e-mail address, home and work address, phone number) to the third parties, publish it publicly, or keep it in the website. Gathered information has a directing feature to be a source for the website’s visitor profile, reporting and promotion of the services.

www.turkiyeklinikleri.com uses the taken information:

-To enhance, improve and maintain the quality of the website

-To generate visitor’s profile and statistical data

-To determine the tendency of the visitors on using our website

-To send print publications/correspondences

-To send press releases or notifications through e-mail

-To generate a list for an event or competition

By using www.turkiyeklinikleri.com you are considered to agree that;

-Ortadoğu Advertisement Presentation Publishing Tourism Education Architecture Industry and Trade Inc. cannot be hold responsible for any user’s illegal and immoral behavior,

-Terms of use may change from time to time,

-It is not responsible for other websites’ contents it cannot control or the harms they may cause although it uses the connection they provided.

Ortadoğu Advertisement Presentation Publishing Tourism Education Architecture Industry and Trade Inc. may block the website to users in the following events:

-Information with wrong, incomplete, deceiving or immoral expressions is recorded to the website,

-Proclamation, advertisement, announcement, libelous expressions are used against natural person or legal identity,

-During various attacks to the website,

-Disruption of the website because of a virus.

Written, visual and audible materials of the website, including the code and the software are under protection by legal legislation.

Without the written consent of Ortadoğu Advertisement Presentation Publishing Tourism Education Architecture Industry and Trade Inc. the information on the website cannot be downloaded, changed, reproduced, copied, republished, posted or distributed.

All rights of the software and the design of the website belong to Ortadoğu Advertisement Presentation Publishing Tourism Education Architecture Industry and Trade Inc.

Ortadoğu Advertisement Presentation Publishing Tourism Education Architecture Industry and Trade Inc. will be pleased to hear your comments about our terms of use. Please share the subjects you think may enrich our website or if there is any problem regarding our website.

info@turkiyeklinikleri.com