Patient Evaluation

Questions you may want to ask:

What is the probability for controlling my pets tumor with radiation therapy?

What, if anything, is known about how long this tumor will be controlled with this type of tumor?

What additional therapies, such as chemotherapy, are recommended to enhance the control of the cancer?

What are the possible acute (early) adverse effects associated with my pets radiation plan?

What are the possible delayed adverse effects associated with my pets radiation plan?

I understand that the radiation treatments themselves do not hurt. However, what can be done to prevent or reduce the adverse effects associated with radiation therapy?

This patient has a white nose and face after radiation treatment for a nasal tumor.

Indications for Stereotactic Radiosurgery (SRS) in Veterinary Medicine: 

Pituitary Tumors:   Radiosurgery is an ideal tool for the treatment of pituitary tumors.  Dose can be focused on the tumor and extraneous dose to the brain can be minimized.  Neurological signs from these tumors, in both dogs and cats, respond extremely well to fractionated radiation therapy.  Although this technique has not been done often in veterinary medicine, in human patients, neurological signs respond as well to SRS as they do to fractionated radiation therapy.  Interestingly, the endocrinopathies in humans associated with pituitary tumors respond more rapidly and durably to SRS.  We have an ongoing study evaluating the endocrine status of pituitary tumors in cats post SRS (link to acc website).  Generally 2 fractions of SRS are required for pituitary tumors. 

Inoperable menigiomas:  SRS is ideal for treating brain tumors.  The dose can be focused on the tumor, while sparing the rest of the brain.   Two-3 fractions are required, based on the size of the tumor and the relationship between tumor size and brain.

Other brain tumors:  SRS may prove to be the best treatment alternative for glial tumors and other brain tumors.  Although long term cure may not be possible, SRS may provide a fairly durable remission without the morbidity associated with surgery. 

Osteosarcomas:  Osteosarcomas are often amenable to SRS.  SRS can deliver an intense dose to the tumor while at the same time deliver a dose appropriate to the soft tissue extension of the disease.  From a biological standpoint, treatment in large doses/fraction makes sense for osteosarcoma, because there is data to suggest that these tumors have a higher alpha/beta ratio than other tumor types.  SRS has been used in veterinary medicine as a non-surgical approach to limb sparing.  In addition, SRS is indicated for axial tumors as well.  The Trilogy also has the capability of doing intensity modulated radiosurgery (IMRS).  This means that the beam can be sculpted using the sliding collimator leaves.  Vertebral tumors can be treated while sparing the spinal cord. 

Liver tumors:  SRS is ideal for treatment of liver tumors.

Palliation:  SRS is commonly used in humans to achieve durable palliation of tumors in the abdominal and thoracic cavities.  A higher dose can be delivered than using regular external beam radiation therapy because dose to the intestines or other critical tissues can be minimized. 

Indications for Intensity Modulated Radiotherapy (IMRT) in Veterinary Medicine:

Nasal tumors:  Canine and feline nasal tumors  should derive great benefit from IMRT.  These tumors have always presented a treatment challenge because of the complex geometry of the head and the shape of the tumor.  The beam sculpting provided by the sliding leaves of the multileaf collimator allows the eyes and skin to be spared, greatly minimizing acute effects.  Total dose can be increased while still minimizing acute effects.  This should lead to improved tumor control. 

Prostate and Bladder tumors:  The acute effects associated with treating in the abdomen and pelvic canal can be minimized by using IMRT.  The field can focus on the tumor, and preferentially spare bowel.  In human cancers, the use of IMRT in these types of cancers has improved tumor control, while improving the quality of life during treatment. 

What to Expect: Patient Evaluation

What to Expect: Therapy

What to Expect: Follow Up
For feedback regarding this site, contact Webmaster at cvmbs-erhs@colostate.edu.
©Copyright 2008 by College of Veterinary Medicine & Biomedical Sciences
Colorado State University. All Rights Reserved.
Apply to CSU | Disclaimer | Equal Opportunity | Privacy Statement
Updated: May 12, 2008