biostudies-literatureUnknown13(2)Kowalchuk RO<h4>Background</h4>Stereotactic body radiation therapy (SBRT) is an effective treatment modality for non-small cell lung cancer (NSCLC); however, there are concerns regarding potential toxicity for centrally located tumors.<h4>Methods</h4>This retrospective study considered patients with SBRT for central lung NSCLC (defined as a tumor within 2 cm of any mediastinal critical structure). The institutional protocol was that patients with central tumors received SBRT less frequently than daily-generally once or twice weekly.<h4>Results</h4>A total of 115 patients with 148 lesions were treated with SBRT to a median 45 [5<b>-</b>60] Gy in 4 [1<b>-</b>5] fractions over a median 5.3 [0<b>-</b>18] days. Many patients treated with this method presented with advanced disease: 58 treatments involved nodal targets, and 42 had stage 3 disease. 52% of patients had chronic obstructive pulmonary disease (COPD), and only 49% had a biopsy, often due to concerns regarding other medical comorbidities. Rates of prior chemotherapy, thoracic surgery, and thoracic radiotherapy were 32%, 21%, and 49%, respectively. Via the Kaplan-Meier method, 2-year overall survival was 65%, and 2-year local control was 77%. Two-year local-progression free survival was 53%, and 2-year progression-survival was 48%. Treatments for stage 3 disease had an impressive 82% 2-year local control that was comparable to early stage treatments. Patients with stage 3 disease had a 2-year overall survival of 59%, which trended towards decreased overall survival compared to early stage patients. There were 13 grade 1 (9%) and 14 grade 2 (9%) toxicities. There were no reported grade ≥3 acute or late toxicities and only 3 cases of pneumonitis.<h4>Conclusions</h4>Our series demonstrates encouraging local control with low rates of toxicity for central lung SBRT, including many stage 3 patients. This may be the result of the relatively large inter-fraction interval. This interval may allow for greater tumor effects (such as reoxygenation) and improved tolerance from normal tissues.Journal of thoracic disease642-652https://www.ebi.ac.uk/biostudies/studies/S-EPMC7947542biostudies-literatureA single institutional experience with central lung stereotactic body radiation therapy demonstrating encouraging results with increased inter-fraction time.PMC7947542Waters MRLarner JMKersh CRKowalchuk RORichardson KMSpencer KMfalseA single institutional experience with central lung stereotactic body radiation therapy demonstrating encouraging results with increased inter-fraction time.<h4>Background</h4>Stereotactic body radiation therapy (SBRT) is an effective treatment modality for non-small cell lung cancer (NSCLC); however, there are concerns regarding potential toxicity for centrally located tumors.<h4>Methods</h4>This retrospective study considered patients with SBRT for central lung NSCLC (defined as a tumor within 2 cm of any mediastinal critical structure). The institutional protocol was that patients with central tumors received SBRT less frequently than daily-generally once or twice weekly.<h4>Results</h4>A total of 115 patients with 148 lesions were treated with SBRT to a median 45 [5<b>-</b>60] Gy in 4 [1<b>-</b>5] fractions over a median 5.3 [0<b>-</b>18] days. Many patients treated with this method presented with advanced disease: 58 treatments involved nodal targets, and 42 had stage 3 disease. 52% of patients had chronic obstructive pulmonary disease (COPD), and only 49% had a biopsy, often due to concerns regarding other medical comorbidities. Rates of prior chemotherapy, thoracic surgery, and thoracic radiotherapy were 32%, 21%, and 49%, respectively. Via the Kaplan-Meier method, 2-year overall survival was 65%, and 2-year local control was 77%. Two-year local-progression free survival was 53%, and 2-year progression-survival was 48%. Treatments for stage 3 disease had an impressive 82% 2-year local control that was comparable to early stage treatments. Patients with stage 3 disease had a 2-year overall survival of 59%, which trended towards decreased overall survival compared to early stage patients. There were 13 grade 1 (9%) and 14 grade 2 (9%) toxicities. There were no reported grade ≥3 acute or late toxicities and only 3 cases of pneumonitis.<h4>Conclusions</h4>Our series demonstrates encouraging local control with low rates of toxicity for central lung SBRT, including many stage 3 patients. This may be the result of the relatively large inter-fraction interval. This interval may allow for greater tumor effects (such as reoxygenation) and improved tolerance from normal tissues.2021-01-01T00:00:00Z2021 Feb2024-11-08T09:13:07.179Z2024-11-08T09:13:07.179ZS-EPMC79475423371753710.21037/jtd-20-2659