Final answer:
Tumor markers are substances found in the blood, urine, or body tissues that can be elevated in cancer. They can be classified into tissue-specific markers and cancer-specific markers. Examples of tissue-specific markers include lactate dehydrogenase and Œ≤-human chorionic gonadotropin, while examples of cancer-specific markers include α-fetoprotein, carbohydrate antigen 19-9, and carcinoembryonic antigen.
Step-by-step explanation:
A tumor marker is a substance found in the blood, urine, or body tissues that can be elevated in cancer, among other tissue types. Tumor markers can be classified into two groups: tissue-specific markers and cancer-specific markers.
Tissue-specific markers are substances related to specific tissues that have developed cancer. Elevated levels of these markers indicate a specific tissue being at fault. Examples of tissue-specific markers include lactate dehydrogenase (LDH) and β-human chorionic gonadotropin (HCG).
On the other hand, cancer-specific markers are related to the presence of certain cancerous tissues. While these markers are not specific for making a diagnosis, they can be useful in monitoring the progress of the disease or the response to treatment. Examples of cancer-specific markers include α-fetoprotein (AFP), carbohydrate antigen 19-9 (CA19-9), and carcinoembryonic antigen (CEA).