ESTRO IORT Task Force/ACROP recommendations for intraoperative radiation therapy in borderline-resected pancreatic cancer

Abstract

Radiation therapy (RT) is a valuable component of multimodal treatment for localized pancreatic cancer. Intraoperative radiation therapy (IORT) is a very precise RT modality to intensify the irradiation effect for cancer involving upper abdominal structures and organs, generally delivered with electrons (IOERT). Unresectable, borderline and resectable disease categories benefit from dose-escalated chemoradiation strategies in the context of active systemic therapy and potential radical surgery. Prolonged preoperative treatment may act as a filter for selecting patients with occult resistant metastatic disease. Encouraging survival rates have been documented in patients treated with preoperative chemoradiation followed by radical surgery and IOERT (>20 months median survival, >35% survival at 3 years). Intensive preoperative treatment, including induction chemotherapy followed by chemoradiation and an IOERT boost, appears to prolong long-term survival within the subset of patients who remain relapse-free for>2 years (>30 months median survival; >40% survival at 3 years). Improvement of local control through higher RT doses has an impact on the survival of patients with a lower tendency towards disease spread. IOERT is a well-accepted approach in the clinical scenario (maturity and reproducibility of results), and extremely accurate in terms of dose-deposition characteristics and normal tissue sparing. The technique can be adapted to systemic therapy and surgical progress. International guidelines (National Comprehensive Cancer Network or NCCN guidelines) currently recommend use of IOERT in cases of close surgical margins and residual disease. We hereby report the ESTRO/ACROP recommendations for performing IOERT in borderline-resectable pancreatic cancer.

Intra-Operative Electron Radiation Therapy: An Update of the Evidence Collected in 40 Years to Search for Models for Electron-FLASH Studies

“…An expert-based task force under the umbrella of the European Society for Radiotherapy and Oncology (ESTRO) condensed the available data in combination with expertise/expert opinion into a total of 6 guidelines concerning soft tissue sarcomas, unresected and borderline-resected pancreatic cancer, locally recurrent and locally advanced rectal cancer, and breast cancer. The ESTRO/ACROP (Advisory Committee for Radiation Oncology Practice) recommendations of all guidelines included the background and requirements for every aspect of clinical IOeRT practice, including patient selection, diagnostic and therapeutic procedures, quality assurance, and reporting [ 25 , 26 , 27 , 28 , 29 , 30 ].…”

“…On the other side, pancreatic cancer is the clinical model that is better documented in the early publications (1980s and 1990s) with a sustained bibliometric representation along 40 years (total of 2307 patients described in 36 publications with unresected localized disease and 2087 post-resected patients in 33 papers) [ 26 , 27 ].…”

Comprehensive multimodal management of borderline resectable pancreatic cancer: Current status and progress

“…The overall complication rate of IORT was 26.7%, including gastroparesis, gastrointestinal bleeding, pancreatic leakage, and celiac leakage. Clinical and experimental studies have shown that IORT at 10–20 Gy is still well tolerated by organs, even in patients with combined revascularisation[ 135 ]. These findings suggest that patients with postoperative pathology showing residual tumors visible to the naked eye at the margins or positive margins on frozen pathology, or patients with moderate or severe pain and ineffective pain relief, can improve their prognosis and quality of survival following combined IORT.…”

Validation of Monte Carlo-based calculations for megavolt electron beams for IORT and FLASH-IORT

“…IORT treatment has been described for rectal cancer, soft tissue sarcoma, pancreatic cancer and also for the conservative therapy of breast cancer [ 4 , 5 , 6 ]. During the last years, recommendations have been published on the IORT with electrons in breast cancer [ 7 ], borderline-resected pancreatic cancer [ 8 ], soft tissue sarcoma [ 9 ] and rectal cancer [ 10 ]. IORT treatment has also been described for pediatric Ewing sarcoma [ 11 ] and gynecologic malignancies [ 12 ].…”