An Introduction to Cancer

By Dr. Sajal Kakkar in Cancer Care / Oncology

Jan 31 , 2022 | 10 min read


Cancer is a disease in which a person's cells grow out of control and spread to other parts of the body.

Cancer can develop in almost any region of the human body. Normally, human cells grow and multiply (through a process called cell division) to produce new cells when the body needs them.

Cells in the body die when they complete their life cycle or become damaged, and new cells replace them.

Cancer is a group of conditions where the body's cells begin to grow and reproduce in an uncontrolled manner. These cells can then invade and destroy healthy tissues. The cells become cancerous or malignant because of DNA damage. This damage can be inherited, or can be caused by mistakes happening while the normal cell is reproducing or by an environmental stimulus like tobacco.

Cancer cells may travel to other parts of the body, where they begin to grow and form new tumors. This is known as metastases. It happens when cells get into the bloodstream or lymph vessels.

How common is cancer?

Approximately 12,00,000 new cancer cases are diagnosed in India every year. As per the latest National Cancer Registry data, one in eight men and one in nine women in India will develop some form of cancer.

The incidence of cancer and cancer types are influenced by many factors such as age, sex, race, local environmental factors, diet, and genetics. In males, lung followed by oral cavity and throat cancers is the most common, while cervical cancers and breast cancers are the commonest ones diagnosed in females in India.

Differences between cancer cells and normal cells

Cancer cells differ from normal cells in how they grow, what they look like, and what they do in the body. In fact, a normal cell has to go through many steps to become a cancer cell.

The main differences between normal cells and cancer cells are as follows:

  1. Growth

    Normal cells stop growing when there are enough cells. For example, when cells are made to repair a tear in the skin, new cells stop being made when there are enough cells to fill the hole.

  2. Communication

    Similar to normal cells, cancer cells do not interact with other cells.

    Signals from other cells are received by normal cells. These signals have no effect on cancerous cells.

  3. Cell Repair and Cell Death

    Homeostasis is the body's way of ensuring that all of its processes are functioning properly.

    Cancer cells behave substantially differently from healthy cells in a process called homeostasis. Normal cells age or become injured and either repair themselves or die to preserve balance.

    Cancer cells do not self-repair or go through apoptosis.

  4. Attachment

    Normal cells secrete materials that keep them grouped together.

    Cancer cells do not produce these chemicals, allowing chemicals are not produced by cancer cells, which allows them to "float away" to surrounding areas. The body's normal cells stay in their proper location.

    Some cancer cells could not have the adhesion molecules that make them sticky, allowing them to break off and spread to other body parts allows them to break off and spread to other parts of the body through the lymphatic and blood systems.

  5. Appearance

    Normal cells and cancer cells can look very different under a microscope.

    Unlike normal cells, cancer cells often show much greater variability in cell size, some are larger than normal and some are smaller than normal.

  6. Maturation

    Normal cells mature. Cancer cells because they grow rapidly and divide before the cells are completely ripe, and stay immature. Undifferentiated is the term used by doctors to characterize immature cells.

How does cancer develop?

Cancer is a genetic disease, it is caused by changes in genes that control how cancer develops and how our cells work, specifically how they grow and Share.

Genetic changes that cause cancer can occur because of the following reasons:

  • Due to errors found when dividing cells.
  • DNA damage is caused by damage
  • Substances in the environment such as chemicals in tobacco and were caused by UV rays from the sun.
  • Because they were inherited.

The body normally kills cells with damaged DNA before they become cancerous.

However, the body's ability to do this decreases with age. One of the reasons humans are more vulnerable, the reason that why you get cancer later in life is due to this.

When cancer spreads?

Metastatic cancer refers to cancer that has spread from its original site to another area of the body. Metastasis is the process through which cancer cells spread to other areas of the body.

The initial or original cancer's name and cancer cell type also apply to metastatic cancer.

Tissue Changes that are not cancer

Not all changes in body tissues are cancer. However, some tissue changes can develop into cancer if left untreated.

Here are some examples of changes in tissues that are not cancer, but in some cases are controlled because they could become cancer:

  1. Hyperplasia

    Hyperplasia occurs when cells within a tissue are multiplying faster than Normal and extra cells accumulate. However, under the microscope, the cells and the structure of the tissue still look normal.

  2. Dysplasia

    Dysplasia is a more advanced disease than hyperplasia. With dysplasia, there is also an accumulation of extra cells. But the cells look abnormal and there are changes in the way the tissue is organized.

    In general, the more abnormal the cells and tissues look, the more likely it is that cancer will develop.

  3. Carcinoma in situ

    Carcinoma in situ is an even more advanced condition.

    Although sometimes referred to as stage 0 cancers, it is not cancer because the abnormal cells do not invade nearby tissues as much as Cancer cells do.

    But because some carcinomas can become cancer in situ, they are usually treated.

Types of cancer

Typically, cancers are called after the organs or tissues in which they first appear. The type of cell that caused cancer, such as an epithelial cell or a squamous cell, can also be used to define it.

There are over 200 types of cancers, but most fit into the following categories:

  1. Carcinoma

    Carcinoma is the most common type of cancer. They are made up of epithelial cells that line the inner and outer surfaces of the body. Also, check basal cell carcinoma.

  2. Sarcoma

    Sarcomas are cancers that form in bone and soft tissues, including muscle, fat, blood vessels, lymphatics, and fibrous tissue (such as tendons and ligaments).

  3. Leukaemia

    Cancer that starts in the blood-forming tissue of the bone marrow is called leukemia. These cancers do not form solid tumors.

    Instead, large numbers of abnormal white blood cells (leukemia cells and leukemic blast cells) accumulate in the blood and bone marrow and crowd out normal blood cells.

    Choose the Best Blood Cancer Treatment Hospital in Delhi, India

  4. Lymphoma

    A malignancy called lymphoma starts in lymphocytes. These white blood cells, which are a component of the immune system, combat disease. In lymphoma, aberrant cells build up in the body's lymph nodes, lymph arteries, and other organs.

  5. Multiple Myeloma

    Multiple myeloma is cancer that starts in plasma cells, another type of immune cell. Abnormal plasma cells are called myeloma cells. They accumulate in the bone marrow and form tumors in bones throughout the body.

    Check out - Bone Marrow Cancer Treatment in Delhi, India

  6. Melanoma

    Melanoma is a cancer that begins in cells that become specialized melanocytes cells that produce melanin. Most melanomas form in the skin, but they can also form in other pigmented tissues, such as the eye.

  7. Brain and spinal cord tumors

    Tumors of the brain and spinal cord can take many distinct forms. These tumors are named by the cell type in which they developed and the region of the central nervous system from which they first emerged.

Other types of Cancer

  1. Germ cell tumors

    Germ cell tumors are a type of tumor that starts in the cells from which they originate sperm or ovum. These tumors can appear almost anywhere in the body and can be benign or malignant.

  2. Neuroendocrine tumors

    Neuroendocrine tumors arise from cells that secrete hormones into the blood in response to signals from the nervous system. These tumors, which can produce higher levels of hormones than normal, can cause a wide variety of symptoms.

  3. Carcinoid tumors

    Carcinoid tumors are a type of neuroendocrine tumors. They are slow-growing tumors that are usually found in the gastrointestinal system. Carcinoid tumors can spread to the liver or other parts of the body.

    Checkout - Gastrointestinal Cancer Treatment

Spotting signs of Cancer

Depending on which area of the body is affected, different cancers have different signs and symptoms.

Common signs and symptoms of cancer that aren't specifically cancer-related include:

  • Changes in bowel/bladder habits – Diarrhoea/constipation for no obvious reasons, frequency/urgency while passing urine.
  • A Sore that doesn’t heal.
  • Unusual Bleeding or Discharge – Unexplained blood in urine, stool, between periods, in vomit, or cough.
  • Thickening or Lump – Consult a doctor if you notice a lump anywhere in your body.
  • Indigestion or Difficulty in Swallowing
  • Obvious change in wart or mole.
  • Nagging Cough/Breathlessness/Hoarseness - If you have had a cough, or breathlessness for more than two weeks, or if you had blood in your phlegm.
  • Fatigue, Clumps, or area of ​​swelling that can be felt under the skin
  • Weight fluctuations, such as accidental weight loss or gain
  • Skin changes such as yellowing, darkening, or redness of the skin, non-healing wounds, or changes in existing birthmarks changes
  • Persistent indigestion or discomfort after eating
  • Unexplained persistent fever or night sweats
  • Unexplained persistent muscle or joint pain

What to do if you have worrying symptoms

  • Consult your doctor – He will ask simple questions, examine you, and may ask for some tests.
  • If he/she suspects cancer, then he would refer to an Oncologist.

Find out which cancer screening treatments and tests are best for you.

Reducing the risk of developing cancer

Doctors have identified several possibilities to reduce your risk of cancer, such as:

  • Quit Smoking: Quitting Smoking Now Reduces Your Risk of Cancer in the Future.
  • Limit your time spent in the sun. The dangers of ultraviolet (UV) rays from the sun can raise the risk of developing skin cancer.
  • Eat well. Pick a fruit and vegetable-rich diet. Pick lean proteins and healthy carbohydrates.
  • Work out at least five days a week. A lower risk of cancer is linked to regular exercise. Try to exercise for at least 30 minutes most days of the week.
  • Continue to be a healthy weight. Your chance of developing cancer can rise if you are overweight or obese.
  • Drink alcohol in moderation if you wish.
  • Schedule cancer screenings. Speak

Ask your doctor what types of cancer screening are best for you based on your risk factors.

Treatment of Cancer

Cancer management is teamwork that involves:

  • Primary treatment

    The goal of a Primary treatment is either to completely remove cancer from your body or to destroy all cancer cells.

    Any cancer treatment can be used as primary treatment, but the most common primary cancer treatment for the most common type of cancer is surgery.

  • Adjuvant treatment

    The goal of Adjuvant therapy kills any cancer cells that may remain after primary treatment to reduce the chance of cancer coming back.

  • Palliative care

    Palliative treatments can help relieve the side effects of treatment or signs and symptoms caused by cancer itself. Surgery, radiation, chemotherapy, and hormone therapy can be used to relieve symptoms.

    Other medications can treat symptoms including pain and breathlessness.

  • Surgery

    The main objective is to completely remove the malignancy, if possible.

  • Chemotherapy

    Drugs are used in chemotherapy to kill cancer cells.

  • Radiation therapy

    Radiation therapy uses high-energy rays such as X-rays or protons to destroy cancer cells.

  • Bone marrow transplant

    Your bone marrow is the material in your bones that makes blood cells from blood stem cells. A bone marrow transplant also called a stem cell transplant, your own bone marrow stem cells or those from a donor.

  • Immunotherapy

    The biological therapy known as immunotherapy makes use of the immune system to treat cancer. Because your immune system doesn't identify cancer as an invader, it can thrive unchecked in your body.

  • Hormone therapy

    Some cancers are triggered by hormones in your body. Examples include breast and prostate cancer, removing these hormones from the body or blocking their effects can stop cancer cells from growing through hormone therapy.

  • Targeted drugs

    Targeted drug therapy focuses on specific abnormalities within cancer cells So that they survive.

  • Cryoablation

    This treatment kills cancer cells with cold. In cryoablation, a thin, rod-shaped needle (cryoprosthesis) is inserted through the skin and directly into the cancerous tumor. A gas is pumped into the cryoprobe to freeze the tissue.

    The tissue is then thawed. The freezing and thawing process is repeated multiple times during the same treatment session to kill cancer cells.

  • Radiofrequency ablation

    This treatment uses electrical energy to heat cancer cells and cause them to die.

    During radiofrequency ablation, a doctor inserts a thin needle through the skin or through an incision in the cancerous tissue. Radiofrequency energy penetrates the needle and causes surrounding tissue to heat up, killing nearby cells.

A cancer diagnosis and treatment plan is a key components of any comprehensive cancer control plan. In cancer introduction and treatment, the main goal is to cure cancer patients or significantly prolong their lives and ensure a good quality of life.