Abilities of stereotactic radiation therapy in multiple pulmonary metastases

Objective. Improvement of treatment results in functionally inoperable patients with multiple pulmonary metastases. Material and methods. This study is based on the treatment outcomes of 64 patients diagnosed with multiple pulmonary metastases. Patients were divided into 2 groups: in the 1st (n=37) stereotactic radiotherapy (SRT) was performed, in the 2nd (n=27) surgical treatment (ST). All patients in the SRT group were deemed functionally inoperable. For metastases located in the peripheral zones of the lung, a total dose of 46-60 Gy with a dose per fraction of 15 Gy was delivered in 78.4% of cases. In patients with centrally located lesions, a total dose of 40-50 Gy with a dose per fraction of 8-10 Gy was administered (21.6% of patients). SRT was performed using Elekta linear accelerators with Active Breathing Control (ABC) and target position verification prior to each fraction using X-ray Volume Imaging (XVI). In the surgical group, 70.4% of patients underwent atypical resections, and 29.6% underwent anatomical resections. Results. Radiation pneumonitis grade 1 (RTOG 1) was diagnosed in 13 patients (35.1%) in the SRT group. In the ST one patient (3.7%) developed postoperative wound infection. Local recurrence following SRT was observed in 1 patients (1.6%), and in 3 patients (4.7%) after surgery. Local control (LC) in the SRT group remained stable at 96.2% over both 1- and 3-year follow-up periods. In the surgical group, LC was 100% at 1 year and declined to 76.4% at 3 years. The 1-year and 3-year overall survival (OS) rates in the SRT group were 91.6% and 57.2%, respectively, while in the surgical group they were 92.0% and 50.5%. Conclusion. The conducted analysis demonstrated that SRT and surgical resection provide comparable efficacy in achieving local control of both solitary and multiple pulmonary metastases.