Stereotactic Radiotherapy (SRT)  

Stereotactic radiotherapy damages cancer cells with minimal disruption to surrounding healthy tissues.  

Stereotactic radiotherapy (SRT) delivers high-powered, cancer-fighting radiation directly to tumors with extraordinary precision. A type of external beam radiation therapy, SRT targets a tumor from multiple angles while leaving surrounding healthy tissue largely undisturbed. The radiation oncologists within Tampa General Hospital’s Cancer Institute routinely use SRT and other progressive cancer therapies to achieve world-class outcomes for patients.  A common source of confusion is the difference between SRT and stereotactic radiosurgery (SRS), as both treatments are used to precisely deliver radiation to a tumor. However, SRT involves giving small doses of radiation over multiple sessions, while SRS is administered in a single, high-dose treatment.  

Conditions Treated With Stereotactic Radiotherapy   

Often combined with other therapies and procedures, stereotactic radiotherapy is typically used to treat smaller-sized tumors and cancers in delicate areas, such as:  

  • Lung cancer  
  • Liver cancer  
  • Prostate cancer  
  • Spinal cord tumors  
  • Pancreatic cancer  
  • Brain tumors  
  • Cancer in the lymph nodes    

SRT may also be used to treat benign (noncancerous) brain conditions, including:  

  • Parkinson’s disease  
  • Neuralgias  
  • Pituitary adenomas  
  • Arteriovenous malformations  

Stereotactic Radiotherapy Details 

Stereotactic radiotherapy involves multiple treatments that are strategically administered over time. Most patients have between one and eight sessions, depending on their condition and care preferences.  

Here’s a brief overview of the SRT treatment process:   

  • The patient lays down on a table or couch while special machines are adjusted to send radiation beams to a precise part of the body. The patient may wear a protective mold, depending on where the cancer is located.  
  • During treatment, the patient’s care team watches through a window in another room while maintaining constant communication through an intercom. 
  • SRT sessions are repeated as necessary according to a carefully planned treatment schedule.  

What to Expect 

Stereotactic radiotherapy is usually performed on an outpatient basis, which means patients can leave immediately after the treatment session. However, the patient should bring a friend or family member who can drive them home. SRT is not painful and machinery does not touch the patient during treatment. A session can last anywhere from 15 minutes to two hours.  

As with most cancer treatments, SRT comes with a risk of side effects. The precise delivery of this treatment minimizes potential complications, though, so most patients only experience mild and temporary side effects such as:  

  • Headache  
  • Dizziness  
  • Fatigue   


Cancer cells that are exposed to radiation are unable to duplicate or repair themselves. While stereotactic radiotherapy cannot completely destroy or remove a tumor, it can significantly damage the tumor’s cells, thereby impeding cancer growth.