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.

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Inclusion Criteria:

1. Ages 18 to 85
2. Single or multiple liver tumors or mass (solid, partially solid)
3. Without taking drugs affecting coagulation and/or platelet aggregation are used; If used, the drug has been discontinued for a sufficient period of time (e.g. 1 week)
4. KPS>60 points, no serious or uncontrolled underlying diseases, clinical evaluation patients can tolerate puncture
5. Planned fiducial marker implantation with applicable puncture path
6. With informed consent.

Exclusion Criteria:

1. Poor organ function
2. The lesion close to blood vessels and intestine, or there is portal vein hypertension and superior vena cava compression, etc., which are expected to have high risks of puncture bleeding and intestinal injury
3. Poor compliance, unable to complete coordination
4. Paticipant who is considered inappropriate or unwilling to participate in this clinical trial for other reasons.

participant with liver tumors and plan to implant fiducial marker for radiatherapy.