Grant: Collaborative Health Research Projects

Karim Breast cancer is the most commonly diagnosed cancer in women. In the current era of screening mammography, most women are diagnosed with localized, early stage disease for which treatment will include breast-conserving surgery followed by breast external beam radiotherapy (XRT). Compared to XRT, recent work in Accelerated Partial Breast Irradiation (APBI) techniques such as high dose rate (HDR) brachytherapy, show a dramatic reduction of radiation induced acute skin reactions and a reduction of the overall treatment time by delivering a higher dose per fraction to a reduced volume of breast tissue. In contrast to HDR brachytherapy that requires treatment of the patient for five days, a novel technique was recently developed at Sunnybrook where a permanent breast seed implant (PBSI) using 103-Palladium is administered under local anesthesia in a single one-hour session allowing patients to be discharged the same day. The goals here are to enable effective treatment of breast cancer by ensuring the accurate placement of seeds during surgery and evaluating the seed dose distribution during and at the end of the implantation by guiding the seed implantation and allowing for correction of a less than optimal implant while the patient is still in the operating room and anesthetized. The objective of this research is to develop a selective, photon counting, solid state, semiconductor based gamma-camera dedicated to imaging of low-energy (20 keV) isotopes of 103-Palladium to provide clear visualization and dose distribution of radioactive seeds during the implantation procedure and thus improve state-of-the-art for current breast cancer therapy.