Safety and Efficacy of Endovascular Fiducial Marker Insertion for CyberKnife Stereotactic Radiation Therapy Planning in Early-Stage Lung Cancer.

PURPOSE: To evaluate the safety and efficacy of endovascular fiducial markers (EVFMs) for CyberKnife stereotactic radiation therapy (RT) of malignant lung neoplasms in patients with contraindications to percutaneous fiducial marker (PTFM) placement.

MATERIALS AND METHODS: Between January 2011 and December 2013, 15 patients (7 men and 8 women) aged 59-87 years (mean, 73 y) underwent EVFM placement and 109 patients (54 men and 55 women) aged 55-92 years (mean, 73 y) underwent 114 PTFM placements. All patients who received EVFMs had contraindications to PTFM insertion. Complications were recorded for all 129 procedures. Proportions of markers used for CyberKnife stereotactic RT planning and distance between markers and tumor were assessed in all 15 patients in the EVFM group and in 15 randomly selected patients in the PTFM group.

RESULTS: Sixty-two EVFMs and 56 PTFMs were inserted in the groups of 15 patients. CyberKnife stereotactic RT was not performed in 2 EVFM recipients (8 EVFMs) and 1 PTFM recipient (4 PTFMs). CyberKnife stereotactic RT was planned with the use of 39 of 54 EVFMs (72%) in 13 patients and 37 of 52 PTFMs (71%) in 14 patients. Mean distances between the tumor and EVFMs and PTFMs were 5.5 mm and 2.7 mm, respectively (P = .0152). No complications occurred in the EVFM group. In the PTFM group, 60 of 114 patients (52.6%) had small or moderate pneumothoraxes, 13 (11.4%) had chest tubes inserted, and 5 (4.4%) had self-limiting hemoptysis.

CONCLUSIONS: EVFM is feasible and safe, and may therefore offer an alternative when patients are not candidates for percutaneous marker placement.