Radiotherapy uses high-dose radiation to kill cancer cells or slow their growth. There are two main types: external beam radiotherapy which uses a machine to aim radiation at the cancer from many angles, and internal radiotherapy which places a radioactive source inside the body. The goals of radiotherapy are to precisely deliver radiation to tumors while minimizing damage to healthy tissue, in order to cure the cancer, prolong survival, or relieve symptoms. Modern techniques like IMRT and IGRT further improve targeting accuracy and reduce side effects. Common side effects vary depending on the treatment area but may include fatigue, skin changes, nausea, and organ-specific issues.
2. INTRODUCTION
Radiation therapy (also called radiotherapy) is a cancer treatment that uses
high doses of ionizing radiations to kill cancer cells and shrink tumors.
At high doses, radiation therapy kills cancer cells or slows their growth by
damaging their DNA. Cancer cells whose DNA is damaged beyond repair
stop dividing or die. When the damaged cells die, they are broken down
and removed by the body
Radiation therapy does not kill cancer cells right away. It takes days or
weeks of treatment before DNA is damaged enough for cancer cells to die.
Cancer cells keep dying for weeks or months after radiation therapy ends.
3. AIMS
The aim of radiation therapy is to deliver a precisely measured dose of
irradiation to a defined tumor volume with as minimal damage as possible
to surrounding healthy tissue, resulting in eradication of the tumor, a high
quality of life, and prolongation of survival or palliation of symptoms at a
reasonable cost.
In addition to curative efforts, radiation therapy plays a major role in
cancer management in the effective palliation or prevention of symptoms
of the disease:
Pain can be alleviated,
luminal patency can be restored,
skeletal integrity can be preserved, and
Organ function can be re-established with minimal morbidity
4. TYPES OF RADIATION THERAPY
External beam Or Teletherapy
Internal or Brachytherapy
5. External Beam Radiotherapy (EBRT)
External beam radiation therapy comes from a machine that aims radiation
at your cancer.
Moves around you, sending radiation to a part of your body from many
directions
6. Internal radiation therapy
Internal radiation therapy is a treatment in which a source of radiation is
put inside your body.
Internal radiation therapy with a solid source is called brachytherapy
7. Radiation may be the only treatment you need
Most often, you will have radiation therapy with other cancer treatments,
such as surgery, chemotherapy, and immunotherapy.
Primary Treatment
Neoadjuvant Treatment
Adjuvant Treatment
11. 3DCRT
3D CRT is a cancer treatment that allows doctors to direct radiation beams
to conform to tumor shapes.
Helps in reducing dose received by surrounding tissues
Computer Assisted (CT scans), Magnetic Resonance Imaging (MR scans)
and / or Positron Emission Tomography (PET scans) are used, individually
or by fusion, to create detailed, three dimensional representations of the
tumor and the surrounding organs.
This therapy uses a multileaf collimator (MLC) to precise radiation beam to
targeted area. The MLC is a device with a series of computer-controlled
leaf-like plates. As the radiation beams are very precisely directed, adjacent
normal tissues receives less radiation and are able to heal quickly. Hence,
this treatment is superior to, the conventional 2D treatment.
12. Intensity Modulated Radiation Therapy
(IMRT)
uses advanced computer technology to create a three-dimensional model of a
tumor, and direct precisely-focused beams of radiation at the tumor with
improved accuracy.
IMRT addresses the shortcomings of 3DCRT and improves dose distributions
IMRT is a computer-generated plan which uses multiple small fields called beamlets
to generate complex field shapes to avoid critical normal structures.
IMRT modulates a number of fields as well as intensity within each field, thereby
ensures greater control in delivering dose to the tumor while minimizing dose to
normal structures.
IMRT also helps in dose escalation to tumor there by helping in improving treatment
outcomes.
The decrease in toxicity also helps to improve the quality of life.
14. Image Guided Radiation Therapy
(IGRT)
Image Guided Radiation Therapy or IGRT, helps to improve the delivery of
radiation.
IGRT involves conformal radiation treatment guided by a CT scan, taken in
the treatment room just before the patient is given the radiation
treatment.
15. Stereotactic Radiosurgery (SRS) and
Stereotactic Body Radiation Therapy
(SBRT)
Allows delivery of radiation therapy to the region of abnormality with
submillimetre accuracy
16. Adaptive Radiotherapy
Variations in patient/organ shape
and position could occur during
radiotherapy course. Consequently,
the radiation dose delivered to the
target and critical normal organs
can significantly deviate from
planned doses. It is important that
we identify these changes
happening during treatment and
modify the plan using ‘Adaptive
Radiotherapy’ so as to deliver
accurate doses to tumour and
reducing normal tissue toxicity.
17. SIDE EFFECTS
Brain
Fatigue
Hair loss
Memory or concentration problems
Nausea and vomiting
Skin changes
Headache
Head and Neck
Fatigue
Hair loss
Mouth problems
Skin changes
Taste changes
Throat problems, such as trouble
swallowing, cough
18. SIDE EFFECTS
Breast
Fatigue
Skin changes
Swelling (edema)
Tenderness
Chest
Fatigue
Hair loss
Skin changes
Throat problems, such as trouble
swallowing
Cough
Shortness of breath
19. SIDE EFFECTS
Pelvis
Diarrhea
Fatigue
Hair loss
Nausea and vomiting
Sexual problems (men)
Fertility problems (men)
Sexual problems (women)
Fertility problems (women)
Skin changes
Urinary and bladder problems
Rectum
Diarrhea
Fatigue
Hair loss
Sexual problems (men)
Fertility problems (men)
Sexual problems (women)
Fertility problems (women)
Skin changes
Urinary and bladder problems