Radiation Oncology Kazumi Chino, M.D. Faith Hope and Love Cancer Center.
-
Upload
britney-garrison -
Category
Documents
-
view
213 -
download
0
Transcript of Radiation Oncology Kazumi Chino, M.D. Faith Hope and Love Cancer Center.
![Page 1: Radiation Oncology Kazumi Chino, M.D. Faith Hope and Love Cancer Center.](https://reader030.fdocuments.us/reader030/viewer/2022032607/56649ec55503460f94bcf71f/html5/thumbnails/1.jpg)
Radiation Oncology
Kazumi Chino, M.D.Faith Hope and Love Cancer Center
![Page 2: Radiation Oncology Kazumi Chino, M.D. Faith Hope and Love Cancer Center.](https://reader030.fdocuments.us/reader030/viewer/2022032607/56649ec55503460f94bcf71f/html5/thumbnails/2.jpg)
Radiation Therapy
50-60% of all cancer patients will receive radiation therapy in the course of their illness
That's almost 1,000,000 people a year in the US
![Page 3: Radiation Oncology Kazumi Chino, M.D. Faith Hope and Love Cancer Center.](https://reader030.fdocuments.us/reader030/viewer/2022032607/56649ec55503460f94bcf71f/html5/thumbnails/3.jpg)
A Brief History of Radiation...
1895 Wilhelm Rontgen discovers x-rays
1896 Victor Despeignes uses x-rays in a
stomach cancer: the tumor shrinks and the
patient has less pain but isn't cured
1900 Francis Williams describes cure of a
breast cancer, and recommends early tx
of breast cancers to prevent metastasis
![Page 4: Radiation Oncology Kazumi Chino, M.D. Faith Hope and Love Cancer Center.](https://reader030.fdocuments.us/reader030/viewer/2022032607/56649ec55503460f94bcf71f/html5/thumbnails/4.jpg)
What is Radiation?
Energy from a source, traveling through material or space
So light, heat, and sound are all forms of radiation
Therapeutically, we think of photons and sub-atomic particles, moving through the body to deposit their energy in the target: cancer cells
![Page 5: Radiation Oncology Kazumi Chino, M.D. Faith Hope and Love Cancer Center.](https://reader030.fdocuments.us/reader030/viewer/2022032607/56649ec55503460f94bcf71f/html5/thumbnails/5.jpg)
Linear Accelerator
![Page 6: Radiation Oncology Kazumi Chino, M.D. Faith Hope and Love Cancer Center.](https://reader030.fdocuments.us/reader030/viewer/2022032607/56649ec55503460f94bcf71f/html5/thumbnails/6.jpg)
X-rays penetrate to a certain depth based on their energy, and then interact with tissue:
![Page 7: Radiation Oncology Kazumi Chino, M.D. Faith Hope and Love Cancer Center.](https://reader030.fdocuments.us/reader030/viewer/2022032607/56649ec55503460f94bcf71f/html5/thumbnails/7.jpg)
Compton Electron
The freed e- (free radical) then interacts with whatever is nearby (3-5 nm):
Ionization or ion pair formation by stripping an electron from critical molecules in the cell (DNA) = direct effect
Or ionization of water molecules, making reactive oxygen species = indirect effect
![Page 8: Radiation Oncology Kazumi Chino, M.D. Faith Hope and Love Cancer Center.](https://reader030.fdocuments.us/reader030/viewer/2022032607/56649ec55503460f94bcf71f/html5/thumbnails/8.jpg)
![Page 9: Radiation Oncology Kazumi Chino, M.D. Faith Hope and Love Cancer Center.](https://reader030.fdocuments.us/reader030/viewer/2022032607/56649ec55503460f94bcf71f/html5/thumbnails/9.jpg)
DNA Damage
![Page 10: Radiation Oncology Kazumi Chino, M.D. Faith Hope and Love Cancer Center.](https://reader030.fdocuments.us/reader030/viewer/2022032607/56649ec55503460f94bcf71f/html5/thumbnails/10.jpg)
Radiation Action
Local: within 3-5 nm of initiation, the free radical is spent
Normal tissues have mechanisms to halt division and repair DNA damage
Tumors have frequently lost those checks on replication, making them more easily killed by radiation damage
Other rapidly dividing cells (bone marrow, gut mucosa) are more easily killed as well
![Page 11: Radiation Oncology Kazumi Chino, M.D. Faith Hope and Love Cancer Center.](https://reader030.fdocuments.us/reader030/viewer/2022032607/56649ec55503460f94bcf71f/html5/thumbnails/11.jpg)
Dividing the radiation dose into fractions further exploits the difference between tumor
and normal tissue
![Page 12: Radiation Oncology Kazumi Chino, M.D. Faith Hope and Love Cancer Center.](https://reader030.fdocuments.us/reader030/viewer/2022032607/56649ec55503460f94bcf71f/html5/thumbnails/12.jpg)
Side Effects of Radiation
Rapidly dividing cells are more easily killed by radiation
Side effects are local: within the field of treatment or on it's edge
Early effects occur during treatment
Late effects can occur months to years after treatment
![Page 13: Radiation Oncology Kazumi Chino, M.D. Faith Hope and Love Cancer Center.](https://reader030.fdocuments.us/reader030/viewer/2022032607/56649ec55503460f94bcf71f/html5/thumbnails/13.jpg)
Radiation Dermatitis
Hair loss is also seen in
the treatment field
![Page 14: Radiation Oncology Kazumi Chino, M.D. Faith Hope and Love Cancer Center.](https://reader030.fdocuments.us/reader030/viewer/2022032607/56649ec55503460f94bcf71f/html5/thumbnails/14.jpg)
Mucositis, Esophagitis
Nausea and diarrhea
are also caused by
injury to GI mucosa
![Page 15: Radiation Oncology Kazumi Chino, M.D. Faith Hope and Love Cancer Center.](https://reader030.fdocuments.us/reader030/viewer/2022032607/56649ec55503460f94bcf71f/html5/thumbnails/15.jpg)
More Early Side Effects
Fatigue
Muscle aches in the treatment field, costochondritis with treatments in the chest
Radiation cystitis: increased frequency or urgency of urination, dysuria, hematuria, and an increased susceptibility to UTI
![Page 16: Radiation Oncology Kazumi Chino, M.D. Faith Hope and Love Cancer Center.](https://reader030.fdocuments.us/reader030/viewer/2022032607/56649ec55503460f94bcf71f/html5/thumbnails/16.jpg)
Radiation and Bone Marrow
As low as 2-4 Gy can significantly decrease bone marrow cellularity
30-40 Gy (with conventional fractionation) is enough to ablate bone marrow
LD 50 = 4.5 Gy to the whole body
![Page 17: Radiation Oncology Kazumi Chino, M.D. Faith Hope and Love Cancer Center.](https://reader030.fdocuments.us/reader030/viewer/2022032607/56649ec55503460f94bcf71f/html5/thumbnails/17.jpg)
Active Bone Marrow in Adults
![Page 18: Radiation Oncology Kazumi Chino, M.D. Faith Hope and Love Cancer Center.](https://reader030.fdocuments.us/reader030/viewer/2022032607/56649ec55503460f94bcf71f/html5/thumbnails/18.jpg)
Late Effects From Radiation
Neurocognitive deficits: 1/3 of patients receiving whole brain irradiation will have a decrease in MMSE score, peaking about 4 months after tx
Bone marrow may be replaced with fat or
fibrosis, and damage to osteogenic cells
can increase bone demineralization or
impair healing from fractures
![Page 19: Radiation Oncology Kazumi Chino, M.D. Faith Hope and Love Cancer Center.](https://reader030.fdocuments.us/reader030/viewer/2022032607/56649ec55503460f94bcf71f/html5/thumbnails/19.jpg)
Fibrosis
Radiation can cause fibrosis throughout tissues
In joints, this can limit range of motion
In lymph channels, this
causes lymphedema
![Page 20: Radiation Oncology Kazumi Chino, M.D. Faith Hope and Love Cancer Center.](https://reader030.fdocuments.us/reader030/viewer/2022032607/56649ec55503460f94bcf71f/html5/thumbnails/20.jpg)
Pulmonary Fibrosis
Radiation pneumonitis is an intermediate effect, occurring 2-12 months after treatment
Sx: SOB, low grade fever, dry cough
Inflammation is seen within the tx field
Pneuomonitis does not necessarily entail pulmonary fibrosis in the future