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Department of Radiation Oncology

Department of Radiation Oncology



UC Davis is one of the few centers in Northern California to use Calypso, and other highly sophisticated devices, to track tumors during the course of radiation therapy.

The Calypso 4-D localization system is a new, cutting-edge technology that helps physicians localize and track prostate cancer motion during treatment.  It is often referred to as a GPS system for the body, as it tracks the exact position and motion of the target prior to and during daily treatments.

The Calypso system uses tiny electromagnetic sensors, about the size of a grain of rice, that are implanted in the prostate prior to treatment.  These sensors enable doctors to precisely locate the tumor within the prostate and then continuously monitor that location during delivery of the radiation.  The sensors, which are passive until activated by the Calypso system, are implanted in a simple outpatient procedure similar to a biopsy.