Cancer is a neoplasm which is classified by abnormal cell growth. Cancer can be malign or benign. Because it spreads very fast, it is very difficult to discover this disease and curing people who have cancer. Throughout history variosu clinical methods were developed for the research and detection of tumor diseases, but none of the methods can be used for long term treatment and for stopping the disease. In purpose of early detection and prevention of the disease, the research of biomarkers is developing. Biomarkers or tumor markers are biomolecules which indicate normal and abnormal processes in the human body, or a disease, such as cancer. Because of that the GC-MS tehnique is nowadays more used. This tehnique uses differnt types of tissues and liquids from the human body for the detection of biomarkers. The GC-MS tehnique is composed of the device for gas cromatography, which is used for separation of components from the sample, and the device for mass spectrometry, which is used for the identification of the separated components. By the use of this tehnique a great amont of molecules have been discovered, which can be used as biomarkers, in other words, which can be used in the early detection of cancer and quality tracking of the developing of the disease.