Seed Implants (Brachytherapy)

 


Brachytherapy (seed implants) is a treatment approach that uses minimally invasive techniques to place temporarily radioactive sources directly into a cancerous organ. 


Compared to directing radiation into the body from an outside source, brachytherapy has the distinct physical advantage of having the sources placed within the cancer itself and so radiation dose to adjacent organs is minimized.  This basic advantage was understood soon after the discovery of radioactivity and in 1898 Alexander Graham Bell suggested that radioactive sources should be placed into tumors to arrest their growth.  An additional advantage of this procedure is that the treatment is done in a single surgery that does not require an overnight hospitalization.


In the subsequent century, the field has undergone a rapid and substantial evolution culminating in the modern 3-Dimensional, Intra-Operative Planned ultrasound image guided technique used for Prostate Cancer seed implantation.  We will explore the treatment method currently used, expected side-effects, long-term treatment outcomes and future directions.


INTRODUCTION

Fig 1.  Side View of the male pelvic anatomy showing the relation of the prostate to nearby organs

Fig 2.  View of needle placement at different slice levels of the prostate