Early Detection of Cancer

The incidence of cancer has been rising alarmingly for the last few decades. In India, more than 1200 cancer deaths are reported every day. Cancer can be removed from the body by surgery, provided it is detected early enough when the tumour is localised. Although it is extremely difficult to detect cancer in such an early stage, still, the most important step in our fight against cancer remains its early detection. To make it possible, we should create awareness among the people by educating them about the rising incidence of cancer and by conducting mass cancer screening programmes, for which many cancer-detecting centres are required to be opened throughout the country.

Cancer may be present with a variety of generalised and localised symptoms:

• The general symptoms of cancer include loss of appetite, loss of weight, fatigue, pain, malaise, drowsiness, fever, haemorrhage, anaemia and cachexia.
• The local symptoms vary considerably in different cancers. For example, there may be dysphagia in oesophageal cancer; cough in the lung cancer; abdominal pain in ovarian cancer; bowel obstruction in colorectal cancer; haematuria in the bladder cancer; headache in the brain tumour; and paralysis in the spinal cord tumour.

Similarly, some other symptoms may appear depending on the site of the tumour. If a person is found to have symptoms of cancer, a thorough medical check-up should be performed.

Early detection of Breast Cancer

Breast Cancer can be detected in early stages by conducting self-examination of the breasts. The women above 30 years of age, particularly the nulliparous women and those women, who have a positive family history of the breast cancer, are advised to learn self-examination of the breasts and do it regularly. It should be done every month immediately after the menstrual period when the breasts are soft. If a lump is found in the breast, the lady must consult an oncologist for further investigations. Clinical examination of the breast is recommended every third year to all the women below forty years of age and every year to all the women above forty years of age. Mammography is recommended to all the women above forty years of age to detect breast cancer.

Early detection of Cervix Cancer

To detect cervix cancer, all the women above 35 years of age are advised to undergo a Pap test every year. The Pap test was developed by George Pappainecolau of Cornell University in 1928 and has been used extensively since 1943. It is a simple test, in which a microscopic examination of the cervical cells is performed. The Pap test has already saved the lives of thousands of women all over the world.

Early detection of Uterus Cancer

To detect uterus cancer, an endometrial tissue biopsy is recommended to all the women at the age of menopause.

Early detection of Ovary Cancer

To detect ovary cancer, an annual pelvic examination is recommended to all women during the childbearing age.

To detect oral cancer, any non-healing ulcer in the mouth, especially occurring in the tobacco-chewers and smokers, should be thoroughly investigated.

Early detection of Stomach Cancer

Stomach cancer is usually asymptomatic during the early stages. The symptoms when appear are similar to any other gastric problem and the patient usually gets symptomatic relief from over-the-counter remedies, thus further delaying the diagnosis. To detect stomach cancer in an early stage, the endoscopic examination should be done in all the suspected cases. The patients of peptic ulcer who start losing weight or develop haematemesis should be thoroughly investigated to detect cancer of the stomach.

Early detection of Rectum Cancer

To detect cancer of the rectum, a digital rectal examination is recommended every year to all the persons above forty years of age. Faecal examination for occult blood should be done in all the persons above fifty years of age to detect colorectal cancer. A person having complaints of unusual rectal bleeding and resistant diarrhoea or constipation, should undergo digital rectal examination, sigmoidoscopy and barium enema to detect colorectal cancer.

Early detection of Prostate Cancer

To detect cancer of the prostate, prostate-specific antigen (PSA) and prostatic acid phosphatase (PAP) estimations are recommended to all the men above fifty years of age. The digital rectal examination also helps to detect prostatic cancer.

Early detection of Urinary Bladder Cancer

To detect urinary bladder cancer, cystoscopy is advised to all the suspected cases of the urinary bladder cancer, particularly to those persons, who develop haematuria.

Early detection of Leukaemia

Haemogram and bone marrow cytology is recommended to all the suspected cases of leukaemia.

In India, cancers of the oral cavity, oropharynx, oesophagus, stomach, rectum, colon and the lung are commonly seen in men, whereas cancers of the cervix and the breast commonly affect the Indian women. A regular medical check-up that includes biochemistry, X-rays, ultrasound, computed tomography (CT scan) and magnetic resonance imaging (MRI) is recommended to all the high-risk cases of cancer.

Tumour Markers

Over a period of time, it has been observed that the cancerous cells produce specific chemicals in the body, which include antigens, cytoplasmic proteins, enzymes and hormones. These specific biochemicals produced by the cancerous cells are called the tumour markers because these are telltale marks of the tumours. The tumour markers can be defined as biochemical indicators of cancer. The tumour markers help to confirm the diagnosis of cancer and to determine the response of therapy. These may be used as indicators of recurrence of cancer. The levels of tumour markers are estimated in the plasma and other fluids of the body. Estimation of the tumour markers is of great significance in mass cancer screening programmes.

• Alpha-fetoprotein (AFP) is normally produced by the foetal liver cells. The elevated plasma level of AFP in an adult indicates the presence of liver cancer. The AFP is also found to be raised in cancers of the testis, stomach, pancreas, lung and the ovary.
• Carcino-embryonic antigen (CEA) is a protein, which is produced by cancerous cells of the large intestines, liver, stomach, pancreas, cervix, bladder, kidney, thyroid and the ovary. CEA is also found to be raised in the melanoma, lymphoma and in some cancers of the breast & the lung.
• Prostate-specific antigen (PSA) and prostatic acid phosphatase (PAP) are produced by cancer of the prostate.
• Immunoglobulins are tumour markers of the multiple myeloma. The patients of multiple myeloma were found to excrete an abnormal protein in the urine. This protein was first detected in 1847 by Henry Bence Jones at Guy's hospital in London. Estimation of the Bence Jones protein is still used in the diagnosis of the multiple myeloma. 
• CA 125 is a tumour marker of ovarian cancer. It is also found to be raised in cancers of the uterus, cervix, lung, digestive tract, pancreas, liver, colon and the breast.
• CA 19-9 is a tumour marker of the colorectal and pancreatic cancers. The level of CA 19-9 is also found to be raised in carcinomas of the stomach and the bile duct.
• CA 15-3 is a tumour marker of breast cancer. It is also raised in cancers of the ovary, lung and the prostate.
• CA 27-29 is a tumour marker of breast cancer. It is also found to be raised in cancers of the colon, stomach, kidney, ovary, lung, pancreas and the liver.
• CA 72-4 is a tumour marker of stomach cancer.
• Human chorionic gonadotrophin (hCG) is a tumour marker of trophoblastic and non-seminomatous testicular tumours.
• Neuron-specific enolase is a tumour marker of the small cell lung cancer and neuroblastoma.
• Pancreatic oncofetal antigen (POA) is a tumour marker of pancreatic cancer.
• Lactate dehydrogenase (LDH) is an enzyme that is normally produced by the RBCs, liver, brain and some other tissues of the body. Lactate dehydrogenase is a tumour marker of the non-Hodgkin's lymphoma, leukaemia, Ewing's sarcoma and the testicular tumours.
• 5-Hydroxy indole acetic acid (5-HIAA) is a tumour marker of the carcinoid syndrome.
• Urinary steroids are tumour markers of the adrenal carcinoma and the paraneoplastic Cushing's syndrome.
• Calcitonin is a tumour marker for the medullary cancer of the thyroid, myeloma and the multiple endocrine neoplasia.
• Thyroglobulins are the tumour markers, which indicate recurrence of the metastatic thyroid cancer.
• Catecholamines are tumour markers of pheochromocytoma. 
• Antimalignin antibody screen (AMAS) is a less specific tumour marker, which indicates the presence of cancer anywhere in the body.