Balloon mis-positioning during prostate cancer treatment could affect success of radiation delivery

November 12, 2013 by Garth Sundem, University of Colorado Denver

A University of Colorado Cancer Center study recently published in the journal Physics in Medicine and Biology shows that endorectal balloons commonly used during precise radiation treatment for prostate cancer can deform the prostate in a way that could make radiation miss its mark.

"Use of a balloon allows you to stabilize the anatomy. But what we show is that imprecision with balloon placement could reduce radiation dose coverage over the intended area," says Moyed Miften, PhD, FAAPM, investigator at the CU Cancer Center and chief physicist at the University of Colorado School of Medicine Department of Radiation Oncology.

Specifically, Miften and colleagues including Bernard Jones, Gregory Gan, and Brian Kavanagh studied the technique known as stereotactic body radiation, in which powerful, precisely-targeted radiation is delivered only to cancerous areas of the with the hope of killing tumor tissue. An endorectal balloon is needed to hold the prostate in place while this high dose is delivered. The study used 71 images of 9 patients to show an average endorectal balloon placement error of 0.5 cm in the inferior direction. And these placement errors led to less precise radiation targeting and to uneven coverage over cancerous areas.

"In , we use a CT scan to image a patient's prostate and then plan necessary treatment. But if during treatment the prostate doesn't match this planning image, we can deliver an imprecise dose," Miften says.

With the use of endorectal balloon, Miften and colleagues found prostates could be slightly pushed or squeezed, resulting in the prostate deforming slightly from its original shape and also sometimes tilting slightly from its original position in the body. These deformations can push parts of the prostate outside the area reached by the planned radiation.

"What we see is that whether or not a clinician chooses to use an endorectal balloon along with stereotactic body radiation for , it's essential to perform the procedure with image guidance. The key is acquiring images immediately prior to treatment that ensure the anatomy matches the planning CT," Miften says.

Explore further: Biodegradable implant may lessen side effects of radiation to treat prostate cancer

More information: iopscience.iop.org/0031-9155/58/22/7995/

Related Stories

Biodegradable implant may lessen side effects of radiation to treat prostate cancer

June 10, 2013
Several years ago, Virginia Commonwealth University Massey Cancer Center became the first center in the United States to test an Israeli-invented device designed to increase the space between the prostate and the rectum in ...

Tissue spacers reduce risk of rectal injury for prostate cancer patients

April 29, 2011
Injecting a tissue spacer in the prostate-rectal inter-space is an effective way to reduce the rectal dose for prostate cancer patients receiving radiation therapy, according to research presented April 30, 2011, at the Cancer ...

A promising step forward in prostate cancer treatment

August 6, 2012
When treating prostate cancer with radiotherapy, knowing the prostate cancer position is critical to accurately targeting the radiation beam to avoid missing the tumour and irradiating healthy tissue. Prostate cancer patients ...

Novel radiation therapy safely treats prostate cancer and lowers the risk of recurrence

June 26, 2012
A recent Phase I/II clinical trial has shown that a new combination of radiation therapies developed at Virginia Commonwealth University Massey Cancer Center escalates radiation doses to safely and effectively treat prostate ...

Weight at time of diagnosis linked to prostate cancer mortality

October 29, 2013
Men who are overweight or obese when they are diagnosed with prostate cancer are more likely to die from the disease than men who are of healthy weight, according to a Kaiser Permanente study published today in the journal ...

Two radiotherapy treatments show similar morbidity, cancer control after prostatectomy

May 20, 2013
Intensity-modulated radiation therapy has become the most commonly used type of radiation in prostate cancer, but research from the University of North Carolina suggests that the therapy may not be more effective than older, ...

Recommended for you

Researchers identify a protein that keeps metastatic breast cancer cells dormant

January 23, 2018
A study headed by ICREA researcher Roger Gomis at the Institute for Research in Biomedicine (IRB Barcelona) has identified the genes involved in the latent asymptomatic state of breast cancer metastases. The work sheds light ...

Scientists block the siren call of two aggressive cancers

January 23, 2018
Aggressive cancers like glioblastoma and metastatic breast cancer have in common a siren call that beckons the bone marrow to send along whatever the tumors need to survive and thrive.

Boosting cancer therapy with cross-dressed immune cells

January 22, 2018
Researchers at EPFL have created artificial molecules that can help the immune system to recognize and attack cancer tumors. The study is published in Nature Methods.

Workouts may boost life span after breast cancer

January 22, 2018
(HealthDay)—Longer survival after breast cancer may be as simple as staying fit, new research shows.

Cancer patients who tell their life story find more peace, less depression

January 22, 2018
Fifteen years ago, University of Wisconsin–Madison researcher Meg Wise began interviewing cancer patients nearing the end of life about how they were living with their diagnosis. She was surprised to find that many asked ...

Single blood test screens for eight cancer types

January 18, 2018
Johns Hopkins Kimmel Cancer Center researchers developed a single blood test that screens for eight common cancer types and helps identify the location of the cancer.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.