Safety and Efficacy of Stereotactic Ablative Radiotherapy for Ultra-Central Lung Cancer

Abstract

BackgroundUltra-central lung cancer (UCLC) is difficult to achieve surgical treatment. Over the past few years, stereotactic ablative radiotherapy (SABR) or stereotactic body radiotherapy (SBRT) obviously improved the clinical efficacy and survival of UCLC patients. However, the adapted scheme of radiation therapy is still controversial. For this, a single arm retrospective analysis was performed on UCLC patients treated with SBRT.Material and MethodsWe retrospectively studied primary UCLC patients who were treated with SBRT of 56 Gy/6-8f between 2010 and 2018. UCLC was defined as planning target volume (PTV) touching or overlapping the proximal bronchial tree, trachea, esophagus, heart, pulmonary vein, or pulmonary artery within 2 cm around the bronchial tree in all directions.ResultsA total of 58 patients whose median age was 68 years (range, 46-85) were included in our study, 79.3% of whom did not undergo any previous therapy. The median dose of the PTV was 77.8 Gy (range, 43.3-91.8), and the median PTV of tumors was 6.2 cm3 (range, 12.9-265.0). With a median follow-up of 57 months (range, 6-90 months), the median cumulative overall survival (OS) rate was 58 months (range, 2-105). In addition, the 1-year, 2-year and 5-year OS rates were 94.7%, 75.0% and 45.0%, respectively. In our univariable analysis (p=0.020) and multivariate analysis (p=0.004), the OS rate was associated with the PTV. The 5-year OS rates for PTV <53.0 cm3 and PTV ≥53.0 cm3 were 61.6% and 37.4%, respectively. Regarding toxicity after SBRT, there were two cases (3.5%) with grade ≥3 adverse events, of which 1 case died of sudden severe unexplained hemoptysis.ConclusionsPatients with UCLC can benefit from SBRT at a dose of 56 Gy/6-8f. On the other hand, smaller PTV was associated with superior outcomes, and the cure difference needs to be validated by prospective comparative trials.

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

“…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...…”

Comparative analysis of dose calculation algorithms for CyberKnife-based stereotactic radiotherapy in lung cancer

“…CLC, in line with the recommendation of the International Association for the Study of Lung Cancer (IASLC), refers to a lesion located within 2 cm of isotropic expansion of all essential mediastinal structures like PBT, esophagus, heart, brachial plexus, aorta, spinal cord, phrenic and recurrent laryngeal nerve ( 22 ). For UCLC, the definition varies among authors ( 15 , 16 , 19 , 20 ). Here, we defined UCLC as lesions with PTV adjacent/overlapping with PBT, aorta, or esophagus.…”

“…Choosing an appropriate algorithm for dose calculation is a crucial step in the safe implementation of SBRT treatment in CK. Especially for central lung cancer (CLC) and ultra-central lung cancer (UCLC) in non-small cell lung cancer (NSCLC), the relationship between outcomes and safety has not yet been determined ( 15 – 18 ). Research indicates that patients with CLC who undergo SBRT treatment have documented cases of treatment-related deaths and a higher incidence of adverse events ( 17 ).…”

Dosimetric Analysis of Proximal Bronchial Tree Subsegments to Assess The Risk of Severe Toxicity After Stereotactic Body Radiation Therapy of Ultra-central Lung Tumors

“… [1] , [2] , [3] , [4] , [5] , [6] , [7] , [8] , [9] , [10] , [11] After SBRT, local control (LC) rates of 80.0 % to 97.0 % after two years are comparable to surgical resection. [12] , [13] , [14] , [15] , [16] , [17] , [18] , [19] Furthermore, SBRT is increasingly used in oligometastatic cancer patients. [20] , [21] , [22] , [23] , [24] , [25] , [26] , [27] , [28] , [29] , [30] Despite major progress in the field of radiation-oncology, the safety and efficacy of SBRT in ultra-central lung tumors remains controversial.…”