Long-term survival in patients with NSCLC treated with single-fraction vs. multi-fraction palliative radiotherapy in the case of lung tumor, brain metastases and bone metastases

Background: Patients with advanced non-small cell lung cancer (NSCLC) are candidates for different types of treatment, including chemotherapy and radiotherapy or supportive care. Despite the fatal prognosis in advanced disease, many experienced radiation oncologists will apply radiation at low doses with the intention of palliative care. Methods: We used an extensive database of medical patients diagnosed with NSCLC, treated with palliative radiotherapy at the Oncology Centre in Bydgoszcz, from June 1998 to December 2013. A group of 3202 patients was divided into subgroups: Group A)1762 patients irradiated on the lung tumor (without distant metastases): Total dose: A1) 6Gy/1 fr.(n=19); A2) 8Gy/1fr.(n=276); A3) 20Gy/5fr.(n=1349); A4) 30Gy/10fr.(n=118). Group B) 548 patients irradiated on the central nervous system (CNS) metastases: B1) 20Gy/5fr.(n=476); B2) 30Gy/10fr.(n=72). Group C) 892 patients irradiated on the bone metastases: C1) 8Gy/1fr.(n=452); C2) 10Gy/1fr.(n=30); C3) 20Gy/5fr.(n=341); C4) 30Gy/10fr.(n=69). Results: Patients with irradiation of a lung tumor: The longest OS was observed in the group of patients irradiated with doses of 20 Gy (76%) and 30 Gy (7%). Patients with irradiation of bone metastases: No significant differences in OS were observed between the employed fractionation regimens. Patients with irradiation of CNS metastases: The choice of a higher dose of radiation therapy did not demonstrate differences in median OS values compared to a lower dose. Conclusions: The patients who were prescribed single fraction palliative radiotherapy did not have poorer prognoses or experience shorter survival than patients who were prescribed multi-fraction pRT in the case of lung tumor, brain metastases and bone metastases.