What is Cancer ?
Cancer is a group of diseases characterized by uncontrolled cell division that leads to abnormal tissue growth. Many a times, people often use the terms cancer and tumor synonymously. But all tumours are not cancerous.
There are two main types of tumors: malignant tumours and benign tumours.
Malignant tumours: These are the cancerous cells that can invade and destroy surrounding healthy tissue, including organs. The cancer can spread to distant parts of the body through the lymphatic system or bloodstream. Not all tumours are cancerous.
Benign tumours: These types of tumours do not grow uncontrollably or do not invade neighboring tissues. They do not spread throughout the body.
There are over 200 different known cancers that affect humans. Most of the cancers are named from where they start. For example, lung cancer starts in the lung, and breast cancer starts in the breast. The spread of cancer from one part of the body to another is called metastasis. Symptoms and treatment depend on the cancer type and how advanced it is. Most treatment plans may include surgery, radiation and/or chemotherapy.
Symptoms of cancer, are usually caused by the effect of cancer on the part of body where it is growing. Although symptoms of cancer may appear in the form of general debility including weight loss or tiredness, yet it is generally advised that if anyone is experiencing unusual symptoms for more than a few weeks than he/she should seek medical attention.
Local symptoms: Local symptoms generally occur due to the mass of tumour or its ulceration. For example:
Esophageal cancer can cause narrowing of the esophagus, making it difficult or painful to swallow, Colorectal cancer may lead to narrowing or blockages in the bowel, resulting in changes in bowel habits.
Systemic symptoms: General symptoms occur due to distant effects of the cancer that are not related to direct or metastatic spread. These may include:
- Unintentional weight loss
- Getting extremely tired easily (Fatigue)
- Changes in the skin color/ appearance
Various causes of cancer are:
- Genetic mutations
- Harmful rays due to exposure to sun/ radiation
- Diet and physical activity
- Environmental factors
Cancers can generally be recognized by appearance of signs and symptoms through screening.
Screening: Screening tests help in detecting cancer at an early stage (before the symptoms appear). When abnormal tissue or cancer is found early, it is easy to treat or cure. By the time symptoms appear, the cancer might have grown and spread. This can make the cancer harder to treat or cure. It is important to remember that when a doctor suggests any screening test, it does not always mean that there is a cancer. People with suspected cancer are investigated with medical tests. These tests include Blood tests, X-rays, MRIs, Biopsy, Pap-smears, CT scans and Endoscopy and many more.