Cancer Treatment Centers of America

Calypso® 4D Localization System™

What is the Calypso® 4D Localization System™?

The Calypso® 4D localization system- helps doctors deliver focused doses of radiation with greater accuracy to patients receiving external beam radiation therapy for soft-tissue tumors and for external treatment of tumors in superficial tissues, such as the breast.

Internal organs, such as the prostate, pancreas, liver and adrenal gland, can shift during radiation treatment due to breathing and normal movement in the intestines. Typically, radiation oncologists expand the treatment area to ensure the target is irradiated as it moves. For prostate cancer, for example, this means that healthy tissue near the prostate may also be affected, possibly leading to urinary, bowel and sexual side effects.

Also known as GPS for the Body®, this technology allows our radiation therapy team to continuously track movement of internal organs and concentrate radiation to the tumor. The Calypso system's  beacons are able to show the position of a patient’s tumor 25 times a second, and automatically shut the beam off in the event of a cough, sneeze, stomach bubble or other change that moves the tumor out of the X-ray beam.  By targeting cancer cells and avoiding nearby healthy tissues, Calypso spares the bladder, rectum and other critical structures. Common side effects of radiation treatment—such bowel and urinary frequency and erectile dysfunction in prostate cancer patients—may be greatly minimized.

The Calypso system features a console that allows our radiation oncologists to track the tumor during radiation treatment. Before treatment, patients undergo a simple outpatient procedure, where transponders are inserted into the skin through ultrasound guidance or placed on top of the skin's surface. The transponders then communicate with Calypso during radiation treatment using safe, radiofrequency waves.  If the prostate or other targeted tumor site moves out of position, the X-ray beam is stopped, until the target moves back into position for safe radiation.

Calypso® 4D Localization System™ medical animation