Clinical outcomes of 130 patients with primary and secondary lung tumors treated with Cyberknife robotic stereotactic body radiotherapy

Abstract

Background Authors report clinical outcomes of patients treated with robotic stereotactic body radiotherapy (SBRT) for primary, recurrent and metastatic lung lesions.Patients and methods130 patients with 160 lesions were treated with Cyberknife SBRT, including T1-3 primary lung cancers (54%), recurrent tumors (22%) and pulmonary metastases (24%). The mean biologically equivalent dose (BED10Gy) was 151 Gy (72–180 Gy). Median prescribed dose for peripheral and central lesions was 3×20 Gy and 3×15 Gy, respectively. Local control (LC), overall survival (OS), and cause-specific survival (CSS) rates, early and late toxicities are reported. Statistical analysis was performed to identify factors influencing local tumor control.ResultsMedian follow-up time was 21 months. In univariate analysis, higher dose was associated with better LC and a cut-off value was detected at BED10Gy ≤ 112.5 Gy, resulting in 1-, 2-, and 3-year actuarial LC rates of 93%, vs 73%, 80% vs 61%, and 63% vs 54%, for the high and low dose groups, respectively (p = 0.0061, HR = 0.384). In multivariate analysis, metastatic origin, histological confirmation and larger Planning Target Volume (PTV) were associated with higher risk of local failure. Actuarial OS and CSS rates at 1, 2, and 3 years were 85%, 74% and 62%, and 93%, 89% and 80%, respectively. Acute and late toxicities ≥ Gr 3 were observed in 3 (2%) and 6 patients (5%), respectively.ConclusionsOur favorable LC and survival rates after robotic SBRT, with low rates of severe toxicities, are coherent with the literature data in this mixed, non-selected study population.

Cyberknife® stereotactic radiation therapy for stage I lung cancer and pulmonary metastases: evaluation of local control at 24 months

“…In terms of local control, our results are close to what other studies have recently reported in the literature (3,(12)(13)(14).…”

Treatment planning optimization with beam motion modeling for dynamic arc delivery of SBRT using Cyberknife with multileaf collimation

“…The Cyberknife radiotherapy system has shown itself over the past decade to be a valuable method of delivering a high‐quality treatment, particularly for SBRT . One of its limitations is the long delivery time.…”

“…The Cyberknife radiotherapy system has shown itself over the past decade to be a valuable method of delivering a highquality treatment, particularly for SBRT. [21][22][23][24] One of its limitations is the long delivery time. For MLC treatments, this is because robot motion, MLC leaf motion, and beam-on are all largely performed in a serial fashion.…”

Dosimetric accuracy of delivering SBRT using dynamic arcs on Cyberknife

“…The ability of the Cyberknife system to treat from a variety of noncoplanar beam directions 27 is useful for high-quality treatment of SBRT. [1][2][3][4] Treating from such a range of orientations is time-consuming, so that the total treatment time is long. However, several recent studies have shown that use of a dynamic arc delivery can reduce the treatment time by a factor of approximately two.…”

“…The Cyberknife system (Accuray Inc., Sunnyvale, CA) has shown itself to be a valuable device for treating patients with stereotactic body radiotherapy (SBRT). [1][2][3][4] The short-waveguide 6-MV flattening-filter-free linear accelerator is mounted on a robotic arm and is equipped with either a series of circular collimators, a variable circular diaphragm, or a multileaf collimator (MLC). [5][6][7] The MLC is widely used to allow treatment of larger tumors using fewer monitor units.…”