Recurrence After Stereotactic Body Radiation Therapy Versus Lobectomy for Non-Small Cell Lung Cancer

Association between tumor cell in air space and treatment outcomes in early-stage lung cancer treated with stereotactic body radiation therapy

Background and purpose

Spread-through air space (STAS) is an unfavorable factor in patients with lung cancer treated with surgery. However, the relationship between the treatment outcomes of stereotactic body radiation therapy (SBRT) for lung cancer and STAS has not been adequately investigated. This study aimed to evaluate the impact of tumor cells in the air space (TCIAS), which show a STAS burden, on treatment outcomes in patients with early-stage lung cancer treated with SBRT.

Materials and methods

Data of patients who underwent SBRT for early-stage lung cancer treated with SBRT were retrospectively reviewed. The influence of the TCIAS status on local progression-free (LPF), regional failure-free (RFF), distant failure-free (DFF), progression-free survival (PFS), and overall survival (OS) rates was assessed using univariate and multivariate analyses.

Results

Overall, 68 patients were included. The median follow-up time was 24.3 months. For patients positive/negative for TCIAS, the 2-year LPF, RFF, DFF, PFS, and OS rates were 81.4 %/91.1 %, 73.7 %/96.2 %, 55.9 %/75.3 %, 55.0 %/84.6 %, and 67.8 %/92.2 %, respectively. In the multivariate analysis, TCIAS-positive was a significant unfavorable factor for RFF (hazard ratio [HR]: 4.10; 95 % confidence interval [CI]: 1.04-16.16, p = 0.04), DFF (HR: 2.61, 95 % CI: 1.03-6.57, p = 0.04), and PFS (HR: 2.36; 95 % CI: 1.05-5.30, p = 0.04). By contrast, TCIAS-positive was not a significant risk factor for LPF and OS.

Conclusion

TCIAS-positive is an unfavorable factor for regional and distant failure after SBRT. TCIAS status may be useful in predicting the treatment outcome of SBRT for early-stage lung cancer.

Surgical Evaluation in Patients Undergoing Radiation Therapy for Early-Stage Lung Cancer

BACKGROUND

Stereotactic body radiation therapy (SBRT) is used to treat stage I non-small cell lung cancer (NSCLC) in nonsurgical candidates, although guidelines specify that inoperability be determined in multidisciplinary fashion. We characterized NSCLC patients treated with SBRT undergoing thoracic surgical evaluation (TSUe) and quantified TSUe's impact on time to treatment, receipt of diagnostic staging procedures, and health care costs.

METHODS

Adults with newly diagnosed NSCLC undergoing SBRT were identified in the MarketScan all-payer claims database (2014-2018). TSUe was defined as an outpatient encounter with a thoracic surgeon or multispecialty group. Time to treatment and total costs in the 6 months preceding treatment were examined using multivariable regression by receipt of TSUe, adjusting for demographic and clinical factors.

RESULTS

Of 1894 patients, 36.3% (n = 687) underwent TSUe. Compared with patients without TSUe, these patients were younger (mean age, 73.6 vs 76.3 years) and more likely to undergo invasive biopsy/staging procedures (90% vs 82%) or pulmonary function testing (80.6% vs 69.5%). Patients undergoing TSUe had a median time to treatment of 64 days (interquartile range, 43-98 days), compared with 44 days (interquartile range, 29-70 days) for no TSUe. Adjusted time to treatment was 43% longer (incident rate ratio, 1.43; 95% CI, 1.32-1.54; P < .001) with TSUe. Patients undergoing TSUe also incurred 30% higher costs (adjusted cost ratio, 1.30; 95% CI, 1.20-1.41; P < .001).

CONCLUSIONS

Among patients with early-stage NSCLC undergoing SBRT as primary treatment, a minority are evaluated by a thoracic surgeon. Because they have a longer time to treatment, more invasive diagnostic procedures, and higher costs, this represents a targetable gap to make workup protocols more efficient.

A guide for managing patients with stage I NSCLC: deciding between lobectomy, segmentectomy, wedge, SBRT and ablation-part 4: systematic review of evidence involving SBRT and ablation

Background

Clinical decision-making for patients with stage I lung cancer is complex. It involves multiple options [lobectomy, segmentectomy, wedge, stereotactic body radiotherapy (SBRT), thermal ablation], weighing multiple outcomes (e.g., short-, intermediate-, long-term) and multiple aspects of each (e.g., magnitude of a difference, the degree of confidence in the evidence, and the applicability to the patient and setting at hand). A structure is needed to summarize the relevant evidence for an individual patient and to identify which outcomes have the greatest impact on the decision-making.

Methods

A PubMed systematic review from 2000-2021 of outcomes after SBRT or thermal ablation vs. resection is the focus of this paper. Evidence was abstracted from randomized trials and non-randomized comparisons with at least some adjustment for confounders. The analysis involved careful assessment, including characteristics of patients, settings, residual confounding etc. to expose degrees of uncertainty and applicability to individual patients. Evidence is summarized that provides an at-a-glance overall impression as well as the ability to delve into layers of details of the patients, settings and treatments involved.

Results

Short-term outcomes are meaningfully better after SBRT than resection. SBRT doesn't affect quality-of-life (QOL), on average pulmonary function is not altered, but a minority of patients may experience gradual late toxicity. Adjusted non-randomized comparisons demonstrate a clinically relevant detriment in long-term outcomes after SBRT vs. surgery. The short-term benefits of SBRT over surgery are accentuated with increasing age and compromised patients, but the long-term detriment remains. Ablation is associated with a higher rate of complications than SBRT, but there is little intermediate-term impact on quality-of-life or pulmonary function tests. Adjusted comparisons show a meaningful detriment in long-term outcomes after ablation vs. surgery; there is less difference between ablation and SBRT.

Conclusions

A systematic, comprehensive summary of evidence regarding Stereotactic Body Radiotherapy or thermal ablation vs. resection with attention to aspects of applicability, uncertainty and effect modifiers provides a foundation for a framework for individualized decision-making.

Diagnostic Performance of Electromagnetic Navigation Bronchoscopy-Guided Biopsy for Lung Nodules in the Era of Molecular Testing

Electromagnetic navigation bronchoscopy (ENB) is an emerging technique used to evaluate peripheral lung lesions. The aim of this study was to determine the diagnostic yield, safety profile, and adequacy of specimens obtained using ENB for molecular testing. This single-center, prospective pilot study recruited patients with peripheral pulmonary nodules that were not suitable for biopsy via percutaneous transthoracic needle biopsy methods. The possibility of molecular testing, including epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), and programmed death ligand 1 (PD-L1), was identified with non-small cell lung cancer (NSCLC) tissue obtained using ENB. ENB-guided biopsy was performed on 30 pulmonary nodules in 30 patients. ENB-guided biopsy was successfully performed in 96.6% (29/30) of cases, but one case failed to approach the target lesion. The diagnostic accuracy of ENB-guided biopsy was 68.0% (17/25). Biopsy-related pneumothorax occurred in one patient and there was no major bleeding or deaths related to the procedure. Among 13 patients diagnosed with NSCLC, molecular testing was successfully performed in 92.3% (12/13). ENB-guided biopsy demonstrated acceptable accuracy and excellent sample adequacy, with a high possibility of achieving molecular testing and a good safety profile to evaluate peripheral pulmonary nodules, even when the percutaneous approach was difficult and/or dangerous.

Down Regulation of SIRT2 Reduced ASS Induced NSCLC Apoptosis Through the Release of Autophagy Components via Exosomes

Metastasis of cancer is the main cause of death in many types of cancer. Acute shear stress (ASS) is an important part of tumor micro-environment, it plays a crucial role in tumor invasion and spread. However, less is known about the role of ASS in tumorigenesis and metastasis of NSCLC. In this study, NSCLC cells were exposed to ASS (10 dyn/cm²) to explore the effect of ASS in regulation of autophagy and exosome mediated cell survival. Finally, the influence of SIRT2 on NSCLC cell metastasis was verified in vivo. Our data demonstrates that ASS promotes exosome and autophagy components releasing in a time dependent manner, inhibition of exosome release exacerbates ASS induced NSCLC cell apoptosis. Furthermore, we identified that this function was regulated by sirtuin 2 (SIRT2). And, RNA immunoprecipitation (RIP) assay suggested SIRT2 directly bound to the 3′UTR of transcription factor EB (TFEB) and facilitated its mRNA stability. TFEB is a key transcription factor involved in the regulation of many lysosome related genes and plays a critical role in the fusion of autophagosome and lysosome. Altogether, this data revealed that SIRT2 is a mechanical sensitive protein, and it regulates ASS induced cell apoptosis by modulating the release of exosomes and autophagy components, which provides a promising strategy for the treatment of NSCLCs.