Tumour markers are substances, usually proteins that are produced by the body in response to cancer growth or by the cancer tissue itself. Some tumour markers are specific, while others are seen in several cancer types.

Breast cancer tumour markers:
CA15.3 is the most commonly used marker for breast cancer. If the levels go up even after treatment it means the cancer is returning.
CEA called Carcinoembryonic Antigen, a rising level of this may suggest treatment is not working efficiently. This is however not used often for treatment of breast cancer.
Markers for GI tract (Stomach, pancreas, liver or colon):
Alpha feto protein (AFP) is found in liver cancer cells. AFP is important in diagnosing hepatocellular carcinoma and germ cell tumours.
CEA in colon cancer is used for diagnosis.
CA19.9 used in cancer of pancreas
PSA is used for Cancer of the Prostate
Lung cancer for tumour markers:
Lung cancer can be detected if there are high levels of CEA.
This CEA is most frequently tested in blood, also tested in body fluids and biopsy tissue.

CANCER OF BREAST:
It is seen that out of every nine women, one gets breast cancer during her life. Breast cancer is predominantly found in women above the age 80. The most common types of breast cancer can either originate from the milk ducts (ductal carcinoma) or lobules (lobular carcinoma).
The types of breast cancer are:
• Ductal Carcinoma Insitu: This is the initial stage where the cancer cells are present in the milk ducts. Since they are in the initial stage they can be cured easily.
• Invasive Ductal Carcinoma: Here the cancer has spread from the milk ducts to the other parts of the body.
• Invasive Lobular Carcinoma: The cancer has now spread to different parts of the body, diagnosing can be a little difficult here.
Alcohol, smoking and even heredity are the causes of breast cancer. However they can be easily treated if diagnosed early.

CANCER OF LIVER:
Primary liver cancer occurs in the liver itself. Cancer affecting the liver is metastatic in nature, which occurs when tumours from other parts of the body spread to the liver including the colon, lung and breast cancers. These cancers are not named as liver cancer but after the name of the organ from where they originated. Primary liver cancers are rarely discovered early and the current treatment is not effective. Liver cancer occurs when liver cells begin to grow abnormally. It's not completely understood why this happens, but researchers believe that cancer starts with damage to DNA -- the material that contains the instructions for every chemical process in your body, including the rate of cellular growth. DNA damage causes changes in these instructions. One result is that cells may begin to grow out of control and eventually form a tumour -- a mass of malignant cells.
Primary liver cancer is classified into several types based on the cells, they are:
• Hepatocellular carcinoma (HPC)- HPC is the most common type of liver cancer. It is found in adults and in children. It originates from the hepatocytes, which are the primary cells of the liver.
• Cholangiocarcinoma - This type of cancer begins in the small tube-like bile ducts within the liver. This type of cancer is sometimes called bile duct cancer.
• Hepatoblastoma - This rare type of liver cancer affects children younger than 4 years of age. Most children with hepatoblastoma can be successfully treated.
• Angiosarcoma or hemangiosarcoma - These rare cancers begin in the blood vessels of the liver and grow very quickly.

CANCER OF LUNGS:
Smokers active or passive account for more than 80 percent of the lung cancer, exposure to chemicals like asbestos and arsenic also lead to lung cancer. Lung cancer mostly affects people above the age of 70 yrs or more. There is difficulty in breathing, excessive chest pain and loss of appetite for those suffering from lung cancer.
Different types of lung cancer:
Small cell Lung Cancer - Over hundred patients who are diagnosed with this cancer more than 20 suffer from this type of cancer. In this type, small cancerous cells are present and they spread very quickly to the other cells.
Squamous cell carcinoma - Cancerous cells are found in the middle of the lung. Smoking remains one of the major causes.
Large cell carcinoma - Cancerous cells are large and round in shape. They spread rapidly.
Adenocarcinoma - Cancerous cells are found in the phlegm- producing cells in the periphery of lungs. Early diagnosis is possible and effective treatment method is chemotherapy however surgery is not advisable.

CANCER OF OVARIES:
Out of every 50 women it is seen that one will develop ovarian cancer. Ovarian cancer affects older people. If someone has ovarian cancer in a family it is likely that the disease can affect the members of the family. Parenting mothers are less likely to develop ovarian cancer. The patient suffers from pain in the abdomen, feels bloated, has difficulty in breathing and feels exhausted. Surgery and chemotherapy are the different treatment methods.

CANCER OF PROSTRATE:
It is seen that out of every 100 men screened for cancer 23 are prostate cancer. Prostate cancer is the second leading cause of cancer exceeded only by lung cancer. It accounts for 13% of the death in men; because of this high death rate the study of prostate cancer is very essential. Prostate cancer develops from the cells of the prostate gland. The prostate gland is in the size of a walnut and is located in front of the rectum, behind the base of the penis, under the bladder. It is found only in men and produces some of the seminal fluid, which protects and nourishes the sperm cells. When is affected by prostate cancer the cancer spreads through out the body to the other cells. The cancer spreads slowly to the other cells without causing many symptoms so diagnosis becomes very difficult. The causes of prostate cancer is not yet thoroughly understood it is seen that it is mostly hereditary or because of genes. If any of our blood relations (brother or father) has the disease it is probable that we acquire the disease too. People who have a large intake of fatty foods, a diet having high calcium level but low levels of fructose are prone to prostate cancer. The people who are likely to get cancer are over the age of 50. Surgery called the Trans-urethra section of the prostate is some times needed to remove the part of the prostate cancer that is pressing on the urethra. If anything is present in the urethra it makes passing of urine very difficult and painful.

CANCER OF KIDNEY:
The kidneys main function is to filter blood and rid the body of excess water, salt and waste products. About four in five cases of kidney cancer affect the tubes inside the kidney that carry out this filtering. Cancer in kidney is mainly seen in men and those who are above the age of 50. Smoking and the work condition are serious contributions to the disease. People working is an environment where they are in constant contact with either asbestos or any other trace metals are more prone to this disease. Simple detection techniques would be blood and urine test. Treatment varies depending on the stage of cancer.

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