Intraoperative radiotherapy. Indications and options in visceral surgery

Intraoperative radiotherapy (IORT) enables a high precision through surgical exposure of the tumor and the tumor bed, which leads to a maximum radiation dose to the tumor while simultaneously protecting normal tissue from radiation as the dose-limiting factor. Therefore, IORT can be particularly advantageous if local tumor control decisively impacts on long-term survival and enables functional preservation. This review summarizes the knowledge gained from a literature search to enable an evidence-based approach with respect to indications and treatment options of IORT for intra-abdominal tumors. Although the effectiveness of IORT cannot be finally assessed due to limited evidence, IORT is established in the clinical practice as a supplement to the multimodal treatment of (recurrent) rectal cancer and sarcomas. Gastric and pancreatic carcinomas are further indications but additional studies are necessary to clearly define the role of IORT in these tumor entities. An important factor to achieve a benefit with IORT seems to be patient selection in order to obtain good local control of local recurrences as well as overall survival rates for patients with primary or recurrent cancer.