This site is 100% ad supported. Please add an exception to adblock for this site.

rad onc 3


undefined, object
copy deck
Why must circumfrential radiation of STS be avoided?
To avoid excessive fibrosis and edema
With the use of a shrinking field technique the total dose for STS may exceed how many cGy?
Hodgkins lymphoma is characterized by the presence of what?
Reed Sternberg cell
Why does spleen involvement in HD indicate a poorer prognosis?
Indicates late stage and increased risk bone marrow or liver involvement.
For head and neck cancers with negative margins what is curative dose with radiation alone?
50 Gy
For head and neck cancers what dose should positive nodes be irradiated for curative tx?
60 Gy
What is the external radiation dose for gross disease in the floor of the mouth?
70 Gy, off cord at 45 Gy
What is the boost dose to primary oropharyngeal tumors?
70 -75 Gy
Describe the route of spread for cancer of the larynx.
There are no capillary lymphatics so mets do not occur until tumor spreads beyond true vocal cords
What is the external radiation dose for glottic lesions confined to the vocal cords?
66 Gy
What is the dose to positive nodes in the neck region of the hypopharynx?
At least 60 Gy
What is the dose for gross disease of the hypopharynx?
70 Gy
What is the initial dose to the lateral neck target volume for nasopharynx?
50.4 Gy
What boost dose is given to nodal disease in nasopharynx?
65-75 Gy depending on staging
What is the dose to the anterior neck in nasopharyngeal disease?
45-50 Gy
Describe the route of spread for gliomas.
Through local invasion along white matter tracts
What is the conventional dose for partial brain fields?
60 Gy
Describe the route of spread for pituitary tumors.
Typically they are benign and cause damage by compression or local invasion.
What is the conventional dose fractionation for pituitary tumors?
45-50 Gy
What dose is needed to eliminate gross HD?
36-44 Gy
What is the survival prognosis for lung caner?
10% in 5 yrs
Describe the conventional dose fractionation used in cancer of the esophagus.
30-50 Gy for palliation
Describe the conventional radiation therapy fractionation for superior vena cava syndrome.
3-4 Gy for 2-3 days followed by conventional fx
what are the two most common malignancies causing SVCS?
Lung caner and lymphomas
Describe the treatment portal for SVCS?
Primary tumor with 2-3 cm margins plus mediastinal, hilar, and superclavicular areas
Describe the treatment portal for spinal cord compression.
Single post port with 3-4 cm margins above and below lesion
Describe the dose to tumor for spinal compression.
30 - 40 Gy in 2 weeks, beginning with higher fractionation for 3-4 tx
What is the conventional dose for pre-op STS?
50 Gy
What is the conventional dose for post-op STS?
65 Gy total dose with field reduction at 45-50
What is the most common STS in children?
What is the long term prognosis for children with rhabdomyosarcoma?
2/3 survivors
What is the conventional CNS radiation dose?
24 Gy/12/2 to whole brain and 12/6/2 to spine with concurrent chemo
The whole abdomen is treated to this dose for ovarian cancer.
25-30 Gy at 1.5/fx
Describe dose fractionation for cancer of the rectum.
45 Gy conv fx, up to 50 Gy advanced disease
Primary lymphatic drainage of lower lip
submental nodes
Most common primary head and neck tumor
squamous cell

Deck Info