Stock Richard, Beyer David, Kaminetsky Jed, Ge William
Radiation Oncology, Mount Sinai Hospital, New York City, NY.
Radiation Oncology, Cancer Centers of Northern Arizona Healthcare, Sedona, AZ.
Brachytherapy. 2017 Sep-Oct;16(5):1007-1012. doi: 10.1016/j.brachy.2017.05.008. Epub 2017 Jul 27.
To evaluate the use of a polymer-encapsulated palladium-103 ( Pd) source with a unique linear radioactive distribution in prostate brachytherapy. This feasibility study assessed dosimetry, ease and efficiency of use, and side effects. The number of needles required for adequate coverage was the primary end point.
CivaString Pd Model CS10 implants were preplanned for 25 patients. CivaStrings were custom manufactured according to plan. CivaStrings were implanted with 18 gauge needles. Post-implant dosimetry was performed at 3-6 weeks.
Monotherapy (125 Gy) was prescribed for 11 implants. External beam radiation with CivaString boost (100 Gy) was prescribed for 14 implants. The mean time to implant the sources was 23.5 min. The number of planned needles and prostate sizes ranged from 14 to 25 and 21-101 cm, respectively. 70% of implants in prostates less than 50 cm required ≤17 needles. Planned source strength ranged from 2.8 U/cm to 3.9 U/cm. Total source strength averaged 216 U (130-323 U) for monotherapy and 154 U (92.4-245 U) for boost. Nomograms were generated at both prescription dose levels.
The linear Pd source provides good dose coverage to the prostate. Prostate volume changes were minimal suggesting minimal swelling using the CivaString device.
