1. Radiation Therapy 1.2.3 hhholdorf
“Radiotherapy and Radiation Oncology”
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2. Historical Background
Radiation therapy uses high-energy radiation to shrink tumors and kill cancer cells by damaging their DNA
The field of Radiation Therapy is currently referred to as
Radiation Oncology
Born not long after the discovery of x-rays in 1895
by physicist Wilhelm Roentgen
Many early advocates of Radiation Therapy relied
instead on the placement of
radioactive sources in close
proximity or even within the
tumor, a technique known
as brachytherapy or internal
Radiation therapy
Early Radiation Therapy Machine

3. Historical Background
Following World War II, England became the primary focus for research
Ralston Patterson established the optimal treatment approaches for a wide variety of tumors undergoing external beam radiotherapy
Together with the noted Physicist Herbert Parker, Patterson developed the basic principles underlying brachytherapy prescription, the so-called “Patterson-Parker Rules”.
By the 1960s, an exciting development was the introduction of high energy (megavoltage) treatment machines, known as linear accelerators or linacs
These machines were capable of:
producing high energy, deeply penetrating beams, allowing for the
very first time treatment of tumors deep inside the body without
excessive damage to the overlying skin and other normal tissue.
Ralston Patterson

4. Historical Background
A prototype linac was developed by Henry Kaplan and his colleagues at Stanford University
The first patient treated using this machine was a child with retinoblastoma (a cancer of the eye)
Treatment was highly successful for more than 40 years later, and this patient remained free of disease with good vision
Many noteworthy Radiation Oncologists made enormous contributions to the field of Oncology:
Malcolm Bagshaw, demonstrated the curative potential of Radiation Therapy in prostate cancer
Today, based in part on his ground breaking work, radiotherapy is recognized as a mainstay in the treatment of prostate cancer
Samuel Hellman, the founding Chair of the Joint Center
for Radiation Therapy was instrumental in establishing
breast conserving therapy (the use of lumpectomy plus
radiation instead of mastectomy) as the treatment of
choice for women with breast cancer
Malcolm Bagshaw
Samuel Hellman

5. Historical Background
Radiation therapy began with radium and with relatively low-voltage diagnostic machines
A major breakthrough took place when it was discovered that daily doses of radiation over several weeks greatly improved the patient’s chance for a cure
The methods and the machines that deliver radiation therapy have steadily improved since the past
Today, radiation is delivered with great precision to destroy cancer tumors while limiting damage to nearby normal tissues

6. Historical Background
The type of radiation therapy prescribed by a radiation oncologist depends on many factors, including:
The type of cancer
The size of the cancer
The cancer’s location in the body
How close the cancer is to normal tissues that are sensitive to radiation
How far into the body the radiation needs to travel
The patient’s general health and medical history
Whether the patient will have other types of cancer treatment
Other factors, such as the patient’s age and other medical conditions

7. Indications for When To Order
Indications for when to use radiation therapy include shrinking a tumor, removing a tumor prior to surgery.

8. Indications for When To Order
Radiation therapy is also used in patients with prostate cancer. External radiation can be used by placing the machine outside the body to send radiation towards the cancer.
Internal radiation can also be used by using a radioactive substance sealed in needles, seeds, wires, or catheters that are placed directly into or near the cancerous site.

9. Indications for When Used
Most common indication for the use of radiation therapy is to treat cancer.
Radiation therapy controls, prevents, and kills cancerous cells in the body.
It also used to shrink and remove cancer tumors. Radiation therapy is commonly applied to the cancerous tumor because of its ability to control cell growth.

10. Risks of Radiation Therapy
Side effects of radiation therapy greatly depend on which part of your body is being exposed to radiation and how much radiation is used.
You may experience no side effects, or you may experience several.
Most side effects are temporary, can be controlled and generally disappear over time once treatment has ended.

11. Risks of Radiation Therapy
Part of body being treated
Common side effects
Any part
Hair loss at treatment site (sometimes permanent), skin irritation at treatment site, fatigue
Head and neck
Dry mouth, thickened saliva, difficulty swallowing, sore throat, changes in the way food tastes, earaches, sore jaw, nausea
Chest
Difficulty swallowing, cough, shortness of breath
Abdomen
Nausea, vomiting, diarrhea
Pelvis
Diarrhea, bladder irritation, frequent urination, sexual dysfunction

12. Benefits of Radiation Therapy
The purpose of radiotherapy is to destroy cancer cells while causing as little damage as possible to normal cells. It can be used to treat many kinds of cancer in almost any part of the body.
Curative treatment, which is sometimes called radical treatment, aims to give long-term benefits to people. Sometimes radiotherapy is given on its own or it may be given alongside other treatment. Radiotherapy may be given before surgery to shrink a tumor or after surgery to stop the growth of cancer cells that may remain. It can also be given before, during or after chemotherapy or hormone treatment to improve overall results.
Palliative treatment aims to shrink tumors and reduce pain or relieve other cancer symptoms. Palliative radiotherapy may also prolong life.

13. A Patient Being Put Through the Test
Steps for Ultrasound Examination of Tumors in Breast Cancer Patients involved in the Case Study:
Sonograms were used to measure skin thickness in relation to ultrasonic (high frequency) waves via the Sequoia 512 scanner machine.
A specific type of transducer was set to particular settings, in terms of gain, depth ranges, and other criteria, such as focal zones, etc. (Refer to Table 1 of article, An ultrasonographic evaluation of skin thickness in breast cancer patients after post-mastectomy radiation therapy)
Scans used certain magnification levels to zoom in and focus on particular areas of skin on the patients for precise dimensions and measurements.
Patients were to lie on their backs on a soft surface.
Points were placed on each patient’s chest to mark the locations for sonographic measurements. These areas included medial, lateral, and midline of the portion of the breast per patient. Points of measurements were also made on the side of the chest that did not receive RT. This was to maintain accurate readings of skin thickness measurements for each patient in the case. (Measured points were marked either 1 cm above or below initial points only if these points were located directly on the scars from the mastectomies.)

14. The Test cont’d
Transducer lied on a heavy coating of gel to prevent inaccurate readings of skin thickness measurements.
All areas of skin were measured in transverse by the same sonographer.
Points ranging from the frontal layer of the epidermis toward the back portion of the dermis area of skin were measured in two-dimensional view.
The points of the breasts that did not receive RT were measured simultaneously to the points of the radiated breasts.
All pictures were then saved for further observations.

15. The Test cont’d
Steps for Radiation Treatments for Patients diagnosed with Breast Cancer:
The participants in the study were to lay on their backs throughout the procedure.
Their arms were to be raised above their heads with bending at the elbows.
A pillow helped support their knees throughout radiation treatment.
Treatment points were drawn on each patient’s chest with a marker surrounding the entire half portion of the thoracic cavity right below the clavicle.
A midline and a line located near the underarm region were also drawn in relation to marking the finalized area to receive radiation.
The entire breast received RT; this included near the underarm area and near the clavicle for all case study patients.
The whole dose was Gy provided over a course of about a month distributed in doses of 2Gy five days per week. (Refer to article.)
Doses were given fairly and distributed as equally as possible to all patients via bolus infusions and highly fixed proportions