The role of endoscopic ultrasound in the radiation treatment of pancreatic tumor

Abstract

Radiotherapy is an established treatment modality for patients with pancreatic cancer. Image-guided radiation therapy (IGRT) allows the delivery of high doses to the tumour, while sparing the sensitive tissues around it, thus reducing side effects. However, the need of precisely contouring and identifying the target lesion is mandatory to be able to perform IGRT. Endoscopic ultrasound has been progressively implemented in the field of radiotherapy as a tool for intra-lesional placement of fiducial markers to perform IGRT and for direct placing of sealed radioactive sources in contact with the target lesions. In the current paper we provide an updated review on the role of endoscopic ultrasound in the radiation treatment of pancreatic cancer, highlighting areas of future research.

Keywords::

• ¹²⁵i seed
• brachytherapy
• cancer
• celiac plexus neurolysis
• endoscopic ultrasound
• fiducial markers
• image-guided radiation therapy
• pancreas
• radiotherapy

Financial & competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

No writing assistance was utilized in the production of this manuscript.

Key issues

• Image-guided radiation treatment (IGRT) is an established treatment modality for patients with pancreatic cancer.

• IGRT needs the precise contouring and identification of the target lesion.

• Gold fiducial markers placement within the target lesion improves image guidance for delivery of radiation therapy to patients with cancer.

• Endoscopic ultrasound (EUS)-guided placement of gold fiducial markers within the target lesion is safe and feasible in about 90% of cases.

• Complications due to EUS-guided placement of fiducial seeds are almost uncommon and self-limiting.

• EUS-guided interstitial brachytherapy of locally advanced pancreatic cancer has showed about 13–20% of partial or minor responses but without significantly increasing the survival.

• The major clinical finding of EUS-guided implantation of ¹²⁵I seeds into pancreatic mass is a partial but transitory relief of pain in about 30% of patients.

• EUS-guided implantation of ¹²⁵I into celiac ganglia allows obtaining partial pain relief in about 78% of patients 3 months after the implantation.

• More well-performed, comparative studies are needed to exactly define the role of EUS in the radiation treatment of pancreatic cancer; however, based on the existing evidence, EUS may facilitate the radiation treatment planning and have a pivotal role in the management of pain in pancreatic cancer patients.

Notes