Cervical cancer is the third most common
cancer in women worldwide; definitive
radiation therapy and concurrent
chemotherapy is the accepted standard of care for patients with node positive or locally advanced
tumors > 4 cm.
Brachytherapy is an important part of definitive
radiotherapy shown to improve overall survival. While results for two-dimensional X-ray based
brachytherapy have been good in terms of local control especially for early stage disease, unexplained toxicities and treatment failures remain. Improvements in
brachytherapy planning have more recently paved the way for three-dimensional image-based
brachytherapy with volumetric optimization which increases
tumor control, reduces toxicity, and helps predict outcomes. Advantages of image-based
brachytherapy include: improved
tumor coverage (especially for large volume disease), decreased dose to critical organs (especially for small cervix), confirmation of applicator placement, and accounting for sigmoid colon dose. A number of modalities for image-based
brachytherapy have emerged including: magnetic resonance imaging (MRI), computed tomography (CT), CT-MRI hybrid, and ultrasound with respective benefits and outcomes data. For practical application of image-based
brachytherapy the Groupe Europeen de Curietherapie-European Society for Therapeutic Radiology and Oncology Working Group and American
Brachytherapy Society working group guideline serve as invaluable tools, additionally here-in we outline our institutional clinical integration of these guidelines. While the body of literature supporting image-based
brachytherapy continues to evolve a number of uncertainties and challenges remain including: applicator reconstruction, increasing resource/cost demands, mobile four-dimensional targets and organs-at-risk, and accurate contouring of "grey zones" to avoid marginal miss. Ongoing studies, including the prospective EMBRACE (an international study of MRI-guided
brachytherapy in locally advanced
cervical cancer) trial, along with continued improvements in imaging, contouring, quality assurance, physics, and
brachytherapy delivery promise to perpetuate the advancement of image-based
brachytherapy to optimize outcomes for
cervical cancer patients.