Survival and Prognostic Factors of Ultra-Central Tumors Treated with Stereotactic Body Radiotherapy

Abstract

Introduction: Stereotactic body radiotherapy (SBRT) reported excellent outcomes and a good tolerability profile in case of central lung tumors, as long as risk-adapted schedules were adopted. High grade toxicity was more frequently observed for tumors directly touching or overlapping the trachea, proximal bronchial tree (PBT), and esophagus. We aim to identify prognostic factors associated with survival for Ultra-Central (UC) tumors. Methods: We retrospectively evaluated patients treated with SBRT for primary or metastatic UC lung tumors. SBRT schedules ranged from 45 to 60 Gy. Results: A total number of 126 ultra-central lung tumors were reviewed. The Median follow-up time was 23 months. Median Overall Survival (OS) and Progression Free Survival (PFS) was 29.3 months and 16 months, respectively. Local Control (LC) rates at 1 and 2 were 86% and 78%, respectively. Female gender, age < 70 years, and tumor size < 5 cm were significantly associated with better OS. The group of patients with tumors close to the trachea but further away from the PBT also correlated with better OS. The acute G2 dysphagia, cough, and dyspnea were 11%, 5%, and 3%, respectively. Acute G3 dyspnea was experienced by one patient. Late G3 toxicity was reported in 4% of patients. Conclusion: risk-adaptive SBRT for ultra-central tumors is safe and effective, even if it remains a high-risk clinical scenario.

Accelerated Hypofractionated Magnetic Resonance Guided Adaptive Radiation Therapy for Ultracentral Lung Tumors

“…Without the ability to perform plan adaptation, the IGRT set-up alone results in a Figure 3. Treatment-related toxicities associated with hypofractionated schedules from this study and other case series, showing the median total dose and median number of fractions for each study [9,[13][14][15][16][17][18]20,21,[23][24][25][26][27][28][29][30][31][32][33][34]36,38,40,42,43]. * Current study.…”

“…Different hypofractionated schedules have been utilized for ultracentral tumors ( Supplementary Table S1 ) [ 9 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 ], but treatment-related toxicities remain concerning ( Figure 3 ) [ 9 , 13 , 14 , 15 , 16 , 17 , 18 , 20 , 21 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 3...…”

“…Different hypofractionated schedules have been utilized for ultracentral tumors (Supplementary Table S1) [9,, but treatment-related toxicities remain concerning (Figure 3) [9,[13][14][15][16][17][18]20,21,[23][24][25][26][27][28][29][30][31][32][33][34]36,38,40,42,43]. Notably, two prior retrospective series detailed their experience with a more conservative hypofractionation schedule, administering a total of 60 Gy in 12 fractions (5 Gy per fraction), utilizing daily cone-beam computerized tomography (CBCT) for online setup and position verification.…”

“… Treatment-related toxicities associated with hypofractionated schedules from this study and other case series, showing the median total dose and median number of fractions for each study [ 9 , 13 , 14 , 15 , 16 , 17 , 18 , 20 , 21 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 36 , 38 , 40 , 42 , 43 ]. * Current study.…”