What is cancer?
Cancer is the uncontrolled growth of abnormal cells in the body. Each
cell in the body contains DNA in its nucleus which controls its life
cycle. For many reasons, this control mechanism stops working. Old cells
do not die and instead grow out of control, forming new, abnormal cells,
or a tumour.
What are the early
symptoms of cancer?
Usually, early cancer does not cause pain. The signs or symptoms
will depend on where the cancer is, how big it is, and how much it
affects the organs or tissues. But sometimes cancer starts in places
where it won’t cause symptoms until it has grown quite large. Given
below are certain general signs and symptoms to watch out for. There may
be other causes for each of these, but it’s important to see a doctor
about them as soon as possible – especially if there’s no other cause
you can identify, the problem lasts a long time, or it gets worse over
time. Do not wait to feel pain.
- White patches inside the mouth or white spots on the tongue
- Recent change or bleeding in a wart or mole or sores that do not heal
- Thickening or lump in the breast or other parts of the body
- Unexplained weight loss or changes in appetite
- Nagging cough or hoarseness
- Excessive weakness or fatigue
- Indigestion or trouble swallowing
- Unexplained night sweats
- Testicular lumps
- Difficult or painful urination
- Unusual bleeding or discharge
- Persistent back pain
- Rectal bleeding
- Unexplained fevers
What causes cancer?
Though it is very difficult to
pinpoint any definite cause, certain substances, known as carcinogens, can
definitely increase your chances of getting cancer.
- Some cancers are caused by faulty lifestyles. For example, tobacco use can
cause cancers of the head and neck region; early menarche and late menopause
can cause breast cancer or early marriage, multiple pregnancies, history of
sexually transmitted disease and multiple sexual partners can cause cervical
- Overexposure to sun without protection can cause skin cancer.
- Exposure to radiation or nuclear fallout can cause cancer. Sometimes,
radiation treatment for one type of cancer can cause another cancer to grow
many years later. Certain chemicals have been linked to cancer, too. Being
exposed to or working with them can increase a person’s risk of cancer.
- About 5 - 10 % of all cancers are linked to genes or mutations that are
inherited from parents.
Some cancers are caused by viruses- Human papilloma viruses (HPVs)-cervical
cancer; Epstein-Barr virus (EBV)-Burkitt lymphoma; Hepatitis B virus (HBV)
and hepatitis C virus (HCV)- liver cancer; Human immunodeficiency virus
What are the risk factors for cancer ?
A risk factor is a faulty lifestyle factor that increases your chance of
getting a disease, such as cancer. Some of the major cancer risk factors
that can be controlled:
- Tobacco use
- Unhealthy or faulty Diet
- No Physical activity
- Being over-weight or obese
- Alcohol use
- Sun exposure
- Environmental exposures, such as radon, lead, and asbestos
- Exposure to infections such as hepatitis, HPV, and HIV
How does cancer spread? What is metastasis?
A cancerous cell originating in one organ of the body has the ability to
move using the blood or lymphatic systems to other organs, colonising and
destroying healthy tissue in the process. That cell manages to divide and
grow, making new blood vessels to feed itself. This process is called
What are the different types of Cancers?
Cancers are divided into different types based on where they originate:
• Carcinoma: They are the most common types of cancers. A carcinoma begins
in the skin or the tissue that covers the surface of internal organs and
glands. Carcinomas usually form solid tumours. Examples of carcinomas
include prostate cancer, breast cancer, lung cancer, and colorectal cancer.
• Sarcomas: A sarcoma begins in the tissues that support and connect the
body like the fat, muscles, nerves, tendons, joints, blood or lymph vessels,
cartilage or bone. Examples are osteosarcoma, chondrosarcoma, liposarcoma
• Leukemia: Cancers that begin in the blood-forming tissue of the bone
marrow are called leukemia. These cancers do not form solid tumours. A large
numbers of abnormal white blood cells build up in the blood and bone marrow,
crowding out normal blood cells. The four main types of leukemia are acute
lymphocytic leukemia (ALL), chronic lymphocytic leukemia (CLL), acute
myeloid leukemia (AML), and chronic myeloid leukemia (CML).
• Lymphomas: Lymphoma is a cancer that begins in the immune system of the
body i.e. a network of vessels and glands that help fight infection. There
are two main types: Hodgkin's lymphoma and non-Hodgkin's lymphoma.
• Multiple Myeloma: Multiple myeloma is cancer that begins in plasma cells,
another type of immune cell. The abnormal plasma cells, called myeloma
cells, build up in the bone marrow and form tumours in bones all through the
• Melanoma: Melanoma is cancer that begins in cells that make melanin, the
pigment that gives skin its colour. Most melanomas form on the skin, but
melanomas can also form in other pigmented tissues, such as the eye.
• Brain and Spinal Cord Tumours: The central nervous system cancer tumours
develop in the brain and spinal cord. These tumours are named based on the
type of cell in which they formed and where the tumour first formed in the
central nervous system.
DIAGNOSIS AND TREATMENT:
Why should cancer be
diagnosed and treated early?
The sooner a cancer is found the less likely it is to have spread to
other parts of the body making it easier to treat, less painful,
expensive and chances of a complete cure become greater.
How is cancer diagnosed? How
can a doctor tell if a growth is cancerous?
An evident cancer sign or symptom usually takes you to your doctor who
may refer you for further tests. Cancer is nearly always confirmed by an
expert who has looked at cell or tissue samples under a microscope.
What are the different tools
or techniques of cancer diagnosis?
If you have a symptom or your screening test result suggests cancer, the
doctor must find out whether it is due to cancer or some other cause.
Along with your personal and family medical history the doctor also may
order laboratory tests, scans, or other procedures. Lab tests are an
important tool to help the doctors come to a final diagnosis and
appropriate treatment protocol.
Imaging Procedures: Imaging procedures create pictures of areas inside
your body that help the doctor see whether a tumour is present. These
pictures can be made in several ways:
a) X-rays: X-rays use low doses of radiation to create pictures of the
inside of your body.
b) Ultrasound: An ultrasound device sends out sound waves that people
cannot hear. The waves bounce off tissues inside your body like an echo.
A computer uses these echoes to create a picture of areas inside your
body. This picture is called a sonogram.
c) CT Scan: An x-ray machine linked to a computer takes a series of
detailed pictures of your organs. You may receive a dye or other
contrast material to highlight areas inside the body. Contrast material
helps make these pictures easier to read.
d) MRI: A strong magnet linked to a computer is used to make detailed
pictures of areas in your body. Your doctor can view these pictures on a
monitor and print them on film.
e) Nuclear scan: For this scan, you receive an injection of a small
amount of radioactive material, which is sometimes called a tracer. It
flows through your bloodstream and collects in certain bones or organs.
A machine called a scanner detects and measures the radioactivity. The
scanner creates pictures of bones or organs on a computer screen or on
f) PET scan: For this scan, you receive an injection of a tracer. Then,
a machine makes 3-D pictures that show where the tracer collects in the
body. These scans show how organs and tissues are working.
g) Biopsy: In most cases, doctors need to do a biopsy to confirm a
diagnosis of cancer. A biopsy is a procedure in which the doctor removes
a sample of tissue. A pathologist then looks at the tissue under a
microscope to see if it is cancer. The sample may be removed in several
i) With a needle: (FNAC - Fine Needle Aspiration Cytology) The doctor
uses a needle to withdraw tissue or fluid.
ii) With an endoscope: The doctor looks at areas inside the body using a
thin, lighted tube called an endoscope. The scope is inserted through a
natural opening, such as the mouth. Then, the doctor uses a special tool
to remove tissue or cells through the tube.
iii) With surgery: Surgery may be excisional or incisional.
- In an excisional biopsy, the surgeon removes the entire tumor. Often
some of the normal tissue around the tumor also is removed to create
- In an incisional biopsy, the surgeon removes just part of the tumor.
What is Staging?
Staging is the process of identifying where a cancer is located and
measuring how far a cancer has spread when it is first diagnosed.
Knowing the stage of your cancer helps your doctor to:
a) Determine the most effective treatment or combination of treatments
for the patient.
b) Discuss the prognosis entire health care team and the patients and
c) Determine treatment effectiveness
d) Compare larger populations with the same diagnosis to research new,
more effective cancer treatments
How is Stage Determined?
On the basis of the tests, scans and other procedures ordered by the
doctors, the stage of cancer is determined.
The numbered system uses stage numbers to identify how far cancer has
a) Stage 0 Cancer : Often referred to as ‘in-situ’ cancer means the
cancer cells are still in the place where they started and have not
spread at all
b) Stage 1 Cancer: Is small and has only spread a little into nearby
tissues. It has not spread to any lymph nodes or other body areas.
c) Stage 2 and 3 Cancer: Means it is larger and may have spread to
nearby tissues or lymph nodes
d) Stage 4 Cancer: Has spread to other areas of the body. Stage 4 cancer
is also called metastatic cancer or advanced cancer.
In the TNM system, there are three categories:
T = tumour | N = lymph nodes | M = metastases
Each of these categories is given a score, and together these scores
show how far the cancer has spread.
How should cancer be
The treatment comprises of surgery, chemotherapy, radiation therapy
What do different types of
cancer treatment entail?
There are many types of cancer treatment. The types of treatment that
you receive will depend on the type of cancer you have and how advanced
it is. The most common types of cancer treatment include:
a) Surgery: Surgery is a procedure in which a surgeon removes the
cancerous tissue or organ and the tissue from the nearby area that might
contain cancer cells. Doctors usually opt for surgery if the cancer
seems to be contained in one area (localised). Sometimes it’s hard to
tell how much surgery is needed until the surgeon sees the extent of the
cancer during the operation. Surgery is most successful when the tumour
has not spread to other areas.
b) Radiation Therapy: Radiation therapy or radiotherapy, often
abbreviated RT, RTx, or XRT, is therapy using ionizing radiation in
appropriate doses to kill or shrink tumours. Radiation destroys cancer
cells or damages them so they can’t grow.
- External radiation: High-energy rays are aimed from an machine.
External radiation is as painless as having an x-ray taken and is
usually done in an outpatient setting. The treatment takes very little
time and is most often given 5 days a week for 5 to 8 weeks, depending
on the size, place, and type of cancer being treated.
- Internal radiation or Brachytherapy: In some cases, radiation may be
given through pellets of radioactive material placed in or near the
tumour. Such implants allow a person to get a higher total dose of
radiation to a smaller area and in a shorter amount of time than with
c) Chemotherapy: Chemotherapy is a treatment that includes a medication
or combination of medications to treat cancer. The drugs target cells
growing at a fast rate such as cancer cells but also affect healthy
cells such as those that line your mouth and intestines and hair,
causing side effects.
d) Immunotherapy: In the last few decades immunotherapy has become an
important part of treating some types of cancer. It is a type of
biological therapy, which means it uses substances made from living
organisms to treat cancer. It may work in these ways:
- Stopping or slowing the growth of cancer cells
- Stopping cancer from spreading to other parts of the body
- Helping the immune system work better at destroying cancer cells
There are several types of immunotherapy, including:
- Monoclonal antibodies
- Non-specific immunotherapy
- Oncolytic virus therapy
- T-cell therapy
- Cancer vaccines
e) Targeted Therapy: Targeted therapy is a special type of chemotherapy
that takes advantage of differences between normal cells and cancer
cells zeroing in on some of the changes that help them grow, divide, and
spread fast and abnormally.
Targeted drugs can work to:
- Block or turn off chemical signals that tell the cancer cell to grow
- Change proteins within the cancer cells so the cells die
- Stop making new blood vessels to feed the cancer cells
- Trigger your immune system to kill the cancer cells
- Carry toxins to the cancer cells to kill them, but not normal cells
As researchers learn more about the cell changes that drive cancer, they
are better able to design promising therapies that target these changes
or block their effects.
f) Hormone Therapy: Hormone therapy is a treatment that uses medicines
to block or lower the amount of hormones in the body to slow down or
stop the growth of cancer especially to treat prostate and breast
cancers that use hormones to grow.
Hormone therapy is used to:
-Treat cancer. Hormone therapy can lessen the chance that cancer will
return or stop or slow its growth.
- Ease cancer symptoms. Hormone therapy may be used to reduce or prevent
symptoms in men with prostate cancer who are not able to have surgery or
g) Stem Cell Transplant: Stem cell transplants are procedures that
restore blood-forming stem cells in people who have had theirs destroyed
by very high doses of chemotherapy or radiation therapy. Healthy
blood-forming stem cells are infused through a needle in the vein. Once
it enters the bloodstream, the stem cells travel to the bone marrow,
where they take the place of the cells that were destroyed by treatment.
The blood-forming stem cells that are used in transplants can come from
the bone marrow, bloodstream, or umbilical cord. Transplants can be:
• Autologous, which means the stem cells come from the patient
• Allogeneic, which means the stem cells come from someone else, a blood
relative or someone who is not related but is a close tissue match.
• Syngeneic, which means the stem cells come from your identical twin,
if you have one
It is very important that the donor and recipient are a close tissue
match to avoid graft rejection. Graft rejection happens when the
recipient’s immune system recognizes the donor cells as foreign and
tries to destroy them.
h) Precision Medicine: Precision medicine is an approach to patient care
that allows doctors to select treatments that are most likely to help
patients based on a genetic understanding of their disease. This may
also be called personalised medicine. Until recently, doctors didn’t
know why people with the same diagnosis sometimes respond to the same
treatment differently. After decades of research, scientists now
i) Tumours have genetic changes that cause cancer to grow and spread
ii) The changes that occur in one person’s tumour cancer may not occur
in others who have the same type of cancer
iii) The same cancer-causing changes may be found in different types of
The hope of precision medicine is that treatments will one day be
tailored to the changes in each person's cancer and patients will
receive drugs that their tumours are most likely to respond to.
What are the Side Effects of
Cancer treatments can cause side effects, problems that occur when
treatment affects healthy tissues or organs. Side effects vary from
person to person and depend upon the amount or frequency of the
treatment, age and other health conditions, the most common known side
effects caused by cancer treatment include:
|• Anaemia (tired, short of breath, and light-headed)
• Alopecia (Hair Loss)
• Appetite Loss
• Bleeding and Bruising (Thrombocytopenia)
• Edema (a condition in which fluid builds up in your body’s tissues
causing swelling or puffiness)
• Memory or Concentration Problems
• Mouth and Throat Problems
• Nausea and Vomiting
• Nerve Problems (Peripheral Neuropathy)
• Sexual and Fertility Problems (Men/Women)
• Skin and Nail Changes
• Sleep Problems
• Urinary and Bladder Problems
Are there any general
precautions and health care tips during cancer treatment?
Patients need to take special care of their health during cancer
treatment. Here are some general tips:
• Be sure to get plenty of rest and sleep as you may feel more tired
• Eat a balanced, healthy diet. Consult a nutritionist or dietician.
• Tell your cancer care team about all medicines and supplements you’re
• Take special care of the skin in the treatment area as it may become
more sensitive or look and feel sunburned.
If you have been cured of
cancer, can you develop another cancer? In the same place? In some other
part of the body?
About 1 - 3% of patients develop a second cancer different from the
original one, called a second primary. However, a cancer can reappear at
any time during survivorship, the most common time being from five to
nine years after completion of treatment. This makes it very important
for cancer survivors to maintain good follow-up health care. Lifetime
monitoring by health care providers who are knowledgeable about
survivorship care is recommended.
What are the factors that
Some of the factors that affect prognosis include:
• The type of cancer and where it is in your body
• The stage of the cancer, which refers to the size of the cancer and if
it has spread to other parts of your body
• The cancer’s grade, which refers to how aggressive the cancer cells
look under a microscope. Grade provides clues about how quickly the
cancer is likely to grow and spread.
• The patients age and how healthy they were before cancer
• How you respond to treatment.
What is the Difference
between Cure and Remission?
Cure means that there are no traces of your cancer after treatment and
the cancer will never come back. Remission means that the signs and
symptoms of your cancer are reduced. Remission can be partial or
complete. In a complete remission, all signs and symptoms of cancer have
disappeared. If you remain in complete remission for 5 years or more,
some doctors may say that you are cured. Still, some cancer cells can
remain in your body for many years after treatment. These cells may
cause a relapse. It is best to be aware of the risk factors for second
cancers and maintain good follow-up health care under advice from your
doctor or knowledgeable health care providers.
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