<prompt> All of the following tumours are associated with organisms, EXCEPT:Gastric carcinomaHepatocellular carcinomaNasopharyngeal carcinomaNon-small cell lung carcinoma  <response>: Cigarette smoking causes 85-90 of cases of non-small cell lung carcinoma. Its etiology is not associated with any organisms. Ceain human malignancies are associated with viruses. Examples include, Burkitts lymphoma and nasopharyngeal carcinoma Epstein-Barr virus Hepatocellular carcinoma hepatitis viruses Cervical cancer T cell leukemia retroviruses Gastric adenocarcinoma H pylori Ref: Morin P.J., Trent J.M., Collins F.S., Vogelstein B. 2012. Chapter 83. Cancer Genetics. In D.L. Longo, A.S. Fauci, D.L. Kasper, S.L. Hauser, J.L. Jameson, J. Loscalzo Eds, Harrisons Principles of Internal Medicine, 18e. 