Displacement Distance and Stabilization Time for Liver Fiducial Marker

Liver malignant tumor, including liver cancer and liver metastasis, is common in China \[1\]. Previous studies have shown that cyber-knife stereotactic radiotherapy is effective and safe for locally advanced liver malignancies with improved local tumor control \[2\]. Real-time tumor tracking in cyber-knife stereotactic radiotherapy is currently used as tumors have respiratory movements \[3\]. At present, fiducial marker is used to realize the real-time track of tumor \[4, 5\]. However, the fiducial marker are likely to displacement usually within 7 days after implantation \[4, 6, 7\]. Therefore, simulated CT are delayed 7 days before the fiducial marker stabilization and significantly extend the radiotherapy planning process, increase the risk of tumor progression. As far as we know, there is no prospective study on the specific displacement distance and duration before the fiducial marker stabilization after implantation. Therefore, the purpose of this study was to study the displacement distance and stabilization time before stereotactic radiotherapy for liver malignant tumors guided by 3D printing template-assisted CT. 1. B.K. Chang, R.D. Timmerman, Stereotactic body radiation therapy: a comprehensive review, Am J Clin Oncol 30 (6) (2007) 637-644. 2. Kato Y, Kamomae T, Kumagai M, Oie Y, Noguchi Y, Okudaira K, et al. Hybrid 3D T1-weighted gradient-echo sequence for fiducial marker detection and tumor delineation via magnetic resonance imaging in liver stereotactic body radiation therapy. 2022;95:9-15. 3. D.K. Bhasin, S.S. Rana, S. Jahagirdar, B. Nagi, Does the pancreas move with respiration? J Gastroenterol Hepatol 21 (9) (2006) 1424-1427. 4. N. Kothary, J.J. Heit, J.D. Louie, W.T. Kuo, B.J. Loo, A. Koong, D.T. Chang, D. Hovsepian, D.Y. Sze, L.V. Hofmann, Safety and efficacy of percutaneous fiducial marker implantation for image-guided radiation therapy, J. Vasc. Interv. Radiol. 20 (2) (2009) 235-239. 5. C.G. Trumm, S.M. Häussler, A. Muacevic, R. Stahl, S. Stintz