Long-Term Outcomes of Salvage Stereotactic Ablative Radiotherapy for Isolated Lung Recurrence of Non-Small Cell Lung Cancer: A Phase II Clinical Trial

The relationship between splenic dose and radiation-induced lymphopenia

Lymphocytes, which are highly sensitive to radiation, play a crucial role in the body's defense against tumors. Radiation-induced lymphopenia has been associated with poorer outcomes in different cancer types. Despite being the largest secondary lymphoid organ, the spleen has not been officially designated as an organ at risk. This study hypothesizes a connection between spleen irradiation and lymphopenia and seeks to establish evidence-based dosage limits for the spleen. We retrospectively analyzed data from 96 patients with locally advanced gastric cancer who received postoperative chemoradiotherapy (CRT) between May 2010 and May 2017. Complete blood counts were collected before, during and after CRT. We established a model for predicting the minimum absolute lymphocyte count (Min ALC) and to investigate potential associations between spleen dosimetric variables and Min ALC. The median follow-up was 60 months. The 5-year overall survival (OS) and disease-free survival (DFS) were 65.2% and 56.8%, respectively. The median values of pre-treatment ALC, Min ALC and post-treatment ALC were 1.40 × 109, 0.23 × 109 and 0.28 × 109/L, respectively. Regression analysis confirmed that the primary tumor location, number of fractions and spleen V5 were significant predictors of Min ALC during radiation therapy. Changes in ALC (ΔALC) were identified as an independent predictor of both OS and DFS. Spleen V5 is an independent predictor for Min ALC, and the maximum dose of the spleen is associated with an increased risk of severe lymphopenia. Therefore, these doses should be restricted in clinical practice. Additionally, ΔALC can serve as a prognostic indicator for adjuvant radiotherapy in gastric cancer.

Novel prognostic signature for lung adenocarcinoma based on immune-related mRNA pairs

Lung adenocarcinoma (LUAD) is a highly lethal malignant tumor. While the involvement of multiple mRNAs in the progression of LUAD is well established, the potential diagnostic value of immune-related mRNAs (irmRNAs) in LUAD remains largely unexplored. In this study, we utilized RNA-seq, clinical data, and immune-related gene information from LUAD patients to identify differentially expressed immune-related mRNAs (DEirmRNAs) and developed a predictive risk model based on specific DEirmRNA pairs closely linked with patient prognosis. We classified patients into high-risk and low-risk groups and analyzed factors such as survival rate, clinical characteristics, gene enrichment, immune cell infiltration, tumor mutation load, and drug susceptibility. We confirmed the expression levels of these DEirmRNAs in tumor tissues using qRT-PCR assay. Our results showed that the low-risk group had a longer survival time and lower tumor mutation burden (TMB) and microsatellite instability (MSI) compared to the high-risk group. The high-risk group also had a significant reduction in the number of certain immune cells and a lower half-maximum inhibitor concentration (IC50). We identified specific DEirmRNA pairs that were up-regulated or down-regulated in tumor tissues compared to adjacent tissues. Our prognostic risk model based on DEirmRNA pairs could be used to predict the prognosis of LUAD patients and provide reference for better treatment.

Radiotherapy in the management of lung oligometastases

In recent years, the development of both medical imaging and new systemic agents (targeted therapy and immunotherapy) have revolutionized the field of oncology, leading to a new entity: oligometastatic disease. Adding local treatment of oligometastases to systemic treatment could lead to prolonged survival with no significant impact on quality of life. Given the high prevalence of lung oligometastases and the new systemic agents coming with increased pulmonary toxicity, this article provides a comprehensive review of the current state-of-art for radiotherapy of lung oligometastases. After reviewing pretreatment workup, the authors define several radiotherapy regimen based on the localization and size of the oligometastases. A comment on the synergistic combination of medical treatment and radiotherapy is also made, projecting on future steps in this specific clinical setting.

Stereotactic ablative radiotherapy with or without immunotherapy for early-stage or isolated lung parenchymal recurrent node-negative non-small-cell lung cancer: an open-label, randomised, phase 2 trial

BACKGROUND

Stereotactic ablative radiotherapy (SABR) is the standard treatment for medically inoperable early-stage non-small-cell lung cancer (NSCLC), but regional or distant relapses, or both, are common. Immunotherapy reduces recurrence and improves survival in people with stage III NSCLC after chemoradiotherapy, but its utility in stage I and II cases is unclear. We therefore conducted a randomised phase 2 trial of SABR alone compared with SABR with immunotherapy (I-SABR) for people with early-stage NSCLC.

METHODS

We did an open-label, randomised, phase 2 trial comparing SABR to I-SABR, conducted at three different hospitals in TX, USA. People aged 18 years or older with histologically proven treatment-naive stage IA-IB (tumour size ≤4 cm, N0M0), stage IIA (tumour size ≤5 cm, N0M0), or stage IIB (tumour size >5 cm and ≤7 cm, N0M0) as per the American Joint Committee on Cancer version 8 staging system or isolated parenchymal recurrences (tumour size ≤7 cm) NSCLC (TanyNanyM0 before definitive surgery or chemoradiotherapy) were included in this trial. Participants were randomly assigned (1:1; using the Pocock & Simon method) to receive SABR with or without four cycles of nivolumab (480 mg, once every 4 weeks, with the first dose on the same day as, or within 36 h after, the first SABR fraction). This trial was unmasked. The primary endpoint was 4-year event-free survival (local, regional, or distant recurrence; second primary lung cancer; or death). Analyses were both intention to treat (ITT) and per protocol. This trial is registered with ClinicalTrials.gov (NCT03110978) and is closed to enrolment.

FINDINGS

From June 30, 2017, to March 22, 2022, 156 participants were randomly assigned, and 141 participants received assigned therapy. At a median 33 months' follow-up, I-SABR significantly improved 4-year event-free survival from 53% (95% CI 42-67%) with SABR to 77% (66-91%; per-protocol population, hazard ratio [HR] 0·38; 95% CI 0·19-0·75; p=0·0056; ITT population, HR 0·42; 95% CI 0·22-0·80; p=0·0080). There were no grade 3 or higher adverse events associated with SABR. In the I-SABR group, ten participants (15%) had grade 3 immunologial adverse events related to nivolumab; none had grade 3 pneumonitis or grade 4 or higher toxicity.

INTERPRETATION

Compared with SABR alone, I-SABR significantly improved event-free survival at 4 years in people with early-stage treatment-naive or lung parenchymal recurrent node-negative NSCLC, with tolerable toxicity. I-SABR could be a treatment option in these participants, but further confirmation from a number of currently accruing phase 3 trials is required.

FUNDING

Bristol-Myers Squibb and MD Anderson Cancer Center Alliance, National Cancer Institute at the National Institutes of Health through Cancer Center Core Support Grant and Clinical and Translational Science Award to The University of Texas MD Anderson Cancer Center.

Re-irradiation for intra-thoracic tumours and extra-thoracic breast cancer: dose accumulation, evaluation of efficacy and toxicity based on a literature review

The improvement seen in the diagnostic procedures and treatment of thoracic tumours means that patients have an increased chance of longer overall survival. Nevertheless, we can still find those who have had a recurrence or developed a secondary cancer in the previously treated area. These patients require retreatment including re-irradiation. We have reviewed the published data on thoracic re-irradiation, which shows that some specific healthy tissues can tolerate a significant dose of irradiation and these patients benefit from aggressive treatment; however, there is a risk of damage to normal tissue under these circumstances. We analysed the literature data on re-irradiation in the areas of vertebral bodies, spinal cord, breast, lung and oesophagus. We evaluated the doses of primary and secondary radiotherapy, the treatment techniques, as well as the local control and median or overall survival in patients treated with re-radiation. The longest OS is reported in the case of re-irradiation after second breast-conserving therapy where the 5-year OS range is 81 to 100% and is shorter in patients with loco-reginal re-irradiation where the 5-y OS range is 18 to 60%. 2-year OS in patients re-irradiated for lung cancer and oesophagus cancer range from 13 to 74% and 18 to 42%, respectively. Majority grade ≥3 toxicity after second breast-conserving therapy was fibrosis up to 35%. For loco-regional breast cancer recurrences, early toxicity occurred in up to 33% of patients resulting in mostly desquamation, while late toxicity was recorded in up to 23% of patients and were mostly ulcerations. Early grade ≥3 lung toxicity developed in up to 39% of patients and up to 20% of Grade 5 hemoptysis. The most frequently observed early toxicity grade ≥3 in oesophageal cancer was oesophagitis recorded in up to 57% of patients, followed by hematological complications which was recorded in up to 50% of patients. The most common late complications included dysphagia, recorded in up to 16.7% of patients. We have shown that thoracic re-irradiation is feasible and effective in achieving local control in some patients. Re-irradiation should be performed with maximum accuracy and care using the best available treatment methods with a highly conformal, image-guided approach. Due to tremendous technological progress in the field of radiotherapy, we can deliver radiation precisely, shorten the overall treatment time and potentially reduce treatment-related toxicities.

Outcomes of SBRT for lung oligo-recurrence of non-small cell lung cancer: a retrospective analysis

The benefit of local ablative therapy (LAT) for oligo-recurrence has been investigated and integrated into the treatment framework. In recent decades, stereotactic body radiation therapy (SBRT) has been increasingly used to eliminate metastasis owing to its high rate of local control and low toxicity. This study aimed to investigate the outcomes of SBRT for patients with lung oligo-recurrence of non-small cell lung cancer (NSCLC) from our therapeutic center. Patients with lung oligo-recurrence of NSCLC treated with SBRT between December 2011 and October 2018 at Cancer Hospital of the University of Chinese Academy of Sciences (Zhejiang Cancer Hospital) were reviewed. The characteristics, treatment-related outcomes, and toxicities of the patients were analyzed. Univariable and multivariable Cox regression were performed to identify the factors associated with survival. A total of 50 patients with lung oligo-recurrence of NSCLC were enrolled. The median follow-up period was 23.6 months. The 3-year local progression-free survival (LPFS), progression-free survival (PFS) and overall survival (OS) after SBRT were 80.2%, 21.9% and 45.3%, respectively. Patients in the subgroup with LAT to all residual diseases showed significantly improved OS and PFS. No treatment-related death occurred after SBRT. SBRT is a feasible option to treat patients with lung oligo-recurrence of NSCLC, with high rates of local control and low toxicity. LAT to all residual diseases was associated with better survival outcomes. Future prospective randomized clinical trials should evaluate SBRT strategies for such patients.

Positron Emission Tomography-Derived Metrics Predict the Probability of Local Relapse After Oligometastasis-Directed Ablative Radiation Therapy

Purpose

Early positron emission tomography–derived metrics post–oligometastasis radioablation may predict impending local relapses (LRs), providing a basis for a timely ablation.

Methods and Materials

Positron emission tomography data of 623 lesions treated with either 24 Gy single-dose radiation therapy (SDRT) (n = 475) or 3 ×  9 Gy stereotactic body radiation therapy (SBRT) (n = 148) were analyzed in a training data set (n = 246) to obtain optimal cutoffs for pretreatment maximum standardized uptake value (SUV_max) and its 3-month posttreatment decline (ΔSUV_max) in predicting LR risk, validated in a data set unseen to testing (n = 377).

Results

At a median of 21.7 months, 91 lesions developed LRs: 39 of 475 (8.2%) after SDRT and 52 of 148 (35.1%) after SBRT. The optimal cutoff values were 12 for SUV_max and –75% for ΔSUV_max. Bivariate SUV_max/ΔSUV_max permutations rendered a 3-tiered LR risk stratification of dual-favorable (low risk), 1 adverse (intermediate risk) and dual-adverse (high risk). Actuarial 5-year local relapse-free survival rates were 93.9% versus 89.6% versus 57.1% (P < .0001) and 76.1% versus 48.3% versus 8.2% (P < .0001) for SDRT and SBRT, respectively. The SBRT area under the ROC curve was 0.71 (95% CI, 0.61-0.79) and the high-risk subgroup yielded a 76.5% true positive LR prediction rate.

Conclusions

The SBRT dual-adverse SUV_max/ΔSUV_max category LR prediction power provides a basis for prospective studies testing whether a timely ablation of impending LRs affects oligometastasis outcomes.

Treatment outcomes of re-irradiation using stereotactic ablative radiotherapy to lung: a propensity score matching analysis

BACKGROUND

The purpose of this study was to compare the treatment efficacy and safety of re-irradiation (re-RT) using stereotactic ablative radiotherapy (SABR) and initial SABR for primary, recurrent lung cancer or metastatic lung tumor.

METHODS

A retrospective review of the medical records of 336 patients who underwent lung SABR was performed. Re-RT was defined as the overlap of the 70% isodose line of second-course SABR with that of the initial radiotherapy, and 20 patients were classified as the re-RT group. The median dose of re-RT using SABR was 54 Gy (range 48-60 Gy), and the median fraction number was 4 (range 4-6). One-to-three case-matched analysis with propensity score matching was used, and 60 patients were included in the initial SABR group of the matched cohort.

RESULTS

The 1- and 2-year local control rates for the re-RT group were 73.9% and 63.3% and those for the initial SABR group in the matched cohort were 92.9% and 87.7%, respectively (P = 0.013). There was no difference in distant metastasis-free, progression-free, and overall survival rates. The crude grade ≥ 2 toxicity rates were 40.0% for the re-RT group and 25.0% for the initial SABR group (P = 0.318). Re-RT group had higher acute grade ≥ 2 toxicity rates (25.0% vs 5.0%, P = 0.031). One incident of grade 3 toxicity (pulmonary) was reported in the re-RT group; there was no grade 4‒5 toxicity.

CONCLUSIONS

The local control rate of the in-field re-RT SABR was lower than that of the initial SABR without compromising the survival rates. The toxicity of re-RT using SABR was acceptable.

Prognostic value of peripheral naive CD8+ T cells in oligometastatic non-small-cell lung cancer

Aim: This study aimed to investigate the prognostic value of peripheral naive and memory CD8⁺ and CD4⁺ T cells and other immune cells in patients with oligometastatic non-small-cell lung cancer (NSCLC) undergoing radiotherapy (RT). Methods: A total of 142 patients with oligometastatic NSCLC treated with RT were enrolled, and their blood samples were collected within 3 days before RT. Immune cells were identified by flow cytometry. Results: Patients with high levels of naive CD8⁺ T cells had longer overall survival (p = 0.004) and progression-free survival (p = 0.001) than those with low levels of naive CD8⁺ T cells. Multivariate analyses revealed that naive CD8⁺ T cells were independently correlated with overall survival (p = 0.019) and progression-free survival (p = 0.024). Conclusion: The results suggest that peripheral naive CD8⁺ T cells may be an independent prognostic indicator for patients with oligometastatic NSCLC undergoing RT.

Multicentre study of microwave ablation for pulmonary oligorecurrence after radical resection of non-small-cell lung cancer

BACKGROUND

Microwave ablation (MWA) is an effective minimally invasive technique for lung tumours. We aim to evaluate its role for pulmonary oligorecurrence after radical surgery of non-small-cell lung cancer (NSCLC).

METHODS

From June 2012 to Jan 2020, a total of 103 patients with pulmonary oligorecurrence after previous radical surgical resection of NSCLC were retrospectively analysed. The primary endpoint was postoperative progression-free survival (PFS). Secondary endpoints were postoperative overall survival (OS), patterns of failure, complications and predictive factors associated with prognosis.

RESULTS

Of the 103 patients identified, 135 pulmonary oligorecurrences developed at a median interval of 34.8 months. In total, 143 sessions of MWA were performed to ablate all the nodules. The median PFS and OS were 15.1 months and 40.6 months, respectively. After MWA, 15 (14.6%) patients had local recurrence as the first event, while intrathoracic oligorecurrence and distant metastases were observed in 45 (43.7%) and 20 (19.4%) patients, respectively. In the multivariate analysis, local recurrence and intrathoracic oligorecurrence were not significant predictors for OS (P = 0.23 and 0.26, respectively). However, distant metastasis was predictive of OS (HR = 5.37, 95% CI, 1.04-27.84, P = 0.04).

CONCLUSION

MWA should be considered to be an effective and safe treatment option for selected patients with pulmonary oligorecurrence after NSCLC radical surgical resection.

The Influence of Severe Radiation-Induced Lymphopenia on Overall Survival in Solid Tumors: A Systematic Review and Meta-Analysis

PURPOSE

Emerging evidence suggests a detrimental prognostic association between radiation-induced lymphopenia (RIL) and pathologic response, progression-free survival, and overall survival (OS) in patients who undergo radiation therapy for cancer. The aim of this study was to systematically review and meta-analyze the prognostic impact of RIL on OS in patients with solid tumors.

METHODS AND MATERIALS

PubMed/MEDLINE and Embase were systematically searched. The analysis included intervention and prognostic studies that reported on the prognostic relationship between RIL and survival in patients with solid tumors. An overall pooled adjusted hazard ratio (aHR) was calculated using a random-effects model. Subgroup analyses for different patient-, tumor-, treatment-, and study-related characteristics were performed using meta-regression.

RESULTS

Pooling of 21 cohorts within 20 eligible studies demonstrated a statistically significant association between OS and grade ≥3 versus grade 0-2 RIL (n = 16; pooled aHR, 1.65; 95% confidence interval [CI], 1.43-1.90) and grade 4 RIL versus grade 0-3 (n = 5; aHR, 1.53; 95% CI, 1.24-1.90). Moderate heterogeneity among aHRs was observed, mostly attributable to overestimated aHRs in 7 studies likely subject to model-overfitting. Subgroup analysis showed significant prognostic impact of grade ≥3 RIL in 4 brain tumor (aHR, 1.63; 95% CI, 1.06-2.51), 4 lung cancer (aHR, 1.52; 95% CI, 1.01-2.29), and 3 pancreatic cancer (aHR, 1.92; 95% CI, 1.10-3.36) cohorts.

CONCLUSIONS

This meta-analysis demonstrates a significant detrimental prognostic association between grade ≥3 lymphopenia and OS in patients receiving radiation therapy for solid tumors. This finding appears consistent for tumors of the brain, thorax, and upper abdomen and provides an imperative to further elucidate the potential survival benefit of lymphopenia-mitigating strategies.

Developments in radiation techniques for thoracic malignancies

Radiation therapy is a cornerstone of modern lung cancer treatment alongside surgery, chemotherapy, immunotherapy and targeted therapies. Advances in radiotherapy techniques have enhanced the accuracy of radiation delivery, which has contributed to the evolution of radiation therapy into a guideline-recommended treatment in both early-stage and locally advanced nonsmall cell lung cancer. Furthermore, although radiotherapy has long been used for palliation of disease in advanced lung cancer, it is increasingly having a role as a locally ablative treatment in patients with oligometastatic disease.This review provides an overview of recent developments in radiation techniques, particularly for non-radiation oncologists who are involved in the care of lung cancer patients. Technical advances are discussed, and findings of recent clinical trials are highlighted, all of which have led to a changing perception of the role of radiation therapy in multidisciplinary care.

Late Central Airway Toxicity after High-Dose Radiotherapy: Clinical Outcomes and a Proposed Bronchoscopic Classification

Simple Summary

High-dose radiotherapy is frequently used to treat lung cancer, however, it can cause serious central airway toxicity. Although radiation toxicity of the lung parenchyma has been studied extensively, relatively little has been published on bronchoscopic findings in the central airways and no standard classification/reporting system exists. With the growing use of high-dose (chemo)radiotherapy and high-dose hypo-fractionated radiotherapy in close proximity to central airways, as well as potential interactions with new systemic therapies, the risks and incidence of central airway toxicity may increase. In this retrospective study, we analyzed patient characteristics and clinical outcomes of 70 patients with central airway toxicity after high-dose radiotherapy. Furthermore, we analyzed the post-radiotherapy bronchoscopic images to identify main patterns of airway toxicity. We identified luminal stenosis and vascular changes as the two main patterns and have proposed a classification system. Preliminary analysis suggests that the pattern and severity of radiation toxicity may be of prognostic value.

Abstract

The study’s purpose was to identify the bronchoscopic patterns of central airway toxicity following high-dose radiotherapy or chemoradiotherapy, and to look at the consequences of these findings. Our institutional bronchoscopy database was accessed to identify main patterns of airway toxicity observed in a seven-year period. A total of 70 patients were identified with central airway toxicity, and the findings of bronchoscopy were used to derive a classification system. Patient characteristics, time from radiotherapy to toxicity, follow-up and survival were retrospectively analyzed. Results: The main bronchoscopic patterns of airway toxicity were vascular changes (telangiectasia, loss of vascularity, necrosis) and stenosis of the lumen (moderate, severe). Indications for bronchoscopy were airway symptoms (n = 28), assessment post-CRT/surgery (n = 12), (suspected) recurrence (n = 21) or assessment of radiological findings (n = 9). Stenosis was revealed by bronchoscopy at a median time of 10.0 months (IQR: 4–23.5) after radiotherapy and subsequent follow-up after identification was 23 months (IQR: 1.5–55). The corresponding findings for vascular changes were 29 months (IQR: 10.5–48.5), and follow-up after identification was nine months (IQR: 2.5–19.5). There was a statistically significant difference in survival rates between patients with necrosis and telangiectasia (p = 0.002) and loss of vascularity (p = 0.001). Eight out of 10 deceased patients with telangiectasia died of other causes and 4/8 patients with necrosis died of other causes. We identified two main patterns of central airway toxicity visualized with bronchoscopy after high-dose radiotherapy or chemoradiotherapy, and propose a bronchoscopic classification system based on these findings. Preliminary analysis suggests that the pattern and severity of radiation damage might be of prognostic value. Prospective data are required to confirm our findings.

Comparison of local therapy in patients with lung oligo-recurrence of non-small-cell lung cancer

BACKGROUND AND OBJECTIVES

The effectiveness of local therapy has been reported in non-small-cell lung cancer (NSCLC) patients with oligo-recurrence. However, there is still no clear consensus on the choice of local therapy. We aimed to examine the choice of local therapy in NSCLC patients with lung oligo-recurrence.

METHODS

Among 1760 consecutive NSCLC patients who underwent complete resection between 1990 and 2008, 535 patients developed recurrence. Lung oligo-recurrence was defined as 1-5 metachronous recurrences limited to the lungs only; such recurrence was found in 97 patients. We examined the differences in the prognosis of each therapy for these patients.

RESULTS

The 5-year postrecurrence survival (PRS) rates in patients who underwent local therapy (n = 54) and those who did not (n = 43) were 55.6% and 31.1%, respectively; it was significantly higher in patients who underwent local therapy (p = 0.004). Among 47 patients who underwent resection or radiation therapy, the 5-year PRS rates were 61.5% and 47.6% (p = 0.258), and the 5-year postrecurrence progression-free survival rates were 30.3% and 24.7% (p = 0.665), respectively, without any significant difference.

CONCLUSIONS

Patients with lung oligo-recurrence should consider local therapy individually, depending on their general condition.

Clinical Outcomes and Prognostic Factors of Salvage Stereotactic Body Radiotherapy for Post-Surgical Thoracic Oligo-Recurrence/Metastasis of Non-Small-Cell Lung Cancer

Purpose

The study aimed to assess the efficacy and safety of stereotactic body radiotherapy (SBRT) using CyberKnife (CK) in patients with postoperative thoracic oligo-recurrence/metastasis of non-small-cell lung cancer (NLCLC), and to analyze the prognostic factors affecting overall survival after SBRT.

Patients and Methods

A total of 44 patients with postoperative thoracic oligo-recurrence/metastatic of NLCLC treated with SBRT were reviewed. Thoracic oligo-recurrence/was defined as 1–3 loco-regional confined to lung lobe, hilar/mediastinal lymph nodes, bronchial stump, or chest wall. Primary endpoints included local control (LC), overall survival (OS), progression-free survival (PFS) and toxicity. Prognostic factors that affected these patients were analyzed by the univariate and multivariate analysis by Kaplan–Meier methods and Cox regression models, respectively.

Results

The median follow-up time after salvage SBRT was 48.5 months. Measuring from the date of salvage SBRT, the median OS of the 44 patients was 52.60 (95% CI: 29.59–75.60) months. 1-,3-and 5-year OS rates were 97.7%, 65.3% and 47.7%, respectively. The 1-,3-year and 5-year LC rates were 97.7%, 85.1% and 80.1%, respectively. At 1, 3 and 5 years, the PFS rates were 77.1%, 28.8% and 5.3%, respectively. Multivariate analysis demonstrated that pre-SBRT neutrophil-to-lymphocyte ratio (NLR) and Charlson comorbidity index (CCI) were independent prognostic factors (p < 0.05). The treatment-related side-effects were well tolerated. No patients developed grade 3 or greater pulmonary toxicity.

Conclusion

SBRT is a promising salvage therapeutic option for postoperative thoracic oligo-recurrence/metastasis of non-small-cell lung cancer with acceptable toxicity. Low pre-SBRT neutrophil-to-lymphocyte ratio (NLR) and low Charlson comorbidity index (CCI) were associated with a better prognosis and longer survival and might be considered as reliable and independent prognostic factors in these patients treated with SBRT.

Stereotactic ablative radiotherapy as single treatment for early stage non-small cell lung cancer: A single institution analysis

BACKGROUND

Stereotactic ablative radiotherapy (SABR) is the current standard-of-care in cases of inoperable early stage non-small cell lung cancer (ES-NSCLC). This study aimed to assess the survival outcomes and recurrence patterns after SABR for ES-NSCLC in a hospital setting.

METHODS

A single-institution retrospective study was performed which included 109 patients who had undergone SABR. The main study endpoints were overall survival (OS), cancer specific survival (CSS), local recurrence-free survival (LRFS), regional recurrence free survival (RRFS) and distant metastasis-free survival (DMFS). Univariate and multivariate analysis were conducted to explore the potential factors which might be related to patient survival.

RESULTS

A total of 109 patients were enrolled into the study. Median follow-up was 44 months (range: 2-93 months). (i) Recurrence results: Among 45 patients with recurrence, 30 patients (28%) had distant metastasis (DM), 17 patients (16%) had local recurrence (LR), 10 patients (9%) had regional recurrence (RR) of lymph nodes and two patients (2%) had second primary lung cancer (SPLC). (ii) Survival results: Median OS, CSS, PFS was 78 months, 78 and 40 months. Two-year OS, CSS, PFS, LRFS, RRFS and DMFS was 84.7%, 87.1%, 69.2%, 86.8%, 92.7% and 78.0%, respectively. Four-year OS, CSS, PFS, LRFS, RRFS and DMFS was 55.6%, 60.7%, 37.3%, 76.3%, 88.4% and 59.4%, respectively. (iii) Univariate and multivariate analyses indicated that age was a prognostic factor of CSS in patients aged <75 years (P = 0.04 HR 2.12 95% confidence interval [CI]: 1.04-4.33).

CONCLUSIONS

Although high survival rates can be achieved in ES-NSCLC patients treated with SABR, using SABR on its own may not be enough. Prolonged surveillance and adjuvant therapy is therefore needed.

Revisiting the formalism of equivalent uniform dose based on the linear-quadratic and universal survival curve models in high-dose stereotactic body radiotherapy

Purpose

To examine the equivalent uniform dose (EUD) formalism using the universal survival curve (USC) applicable to high-dose stereotactic body radiotherapy (SBRT).

Materials and methods

For nine non-small-cell carcinoma cell (NSCLC) lines, the linear-quadratic (LQ) and USC models were used to calculate the EUD of a set of hypothetical two-compartment tumor dose–volume histogram (DVH) models. The dose was varied by ±5%, ±10%, and ±20% about the prescription dose (60 Gy/3 fractions) to the first compartment, with fraction volume varying from 1% and 5% to 30%. Clinical DVHs of 21 SBRT treatments of NSCLC prescribed to the 70–83% isodose lines were also considered. The EUD of non-standard SBRT dose fractionation (EUD_SBRT) was further converted to standard fractionation of 2 Gy (EUD_CFRT) using the LQ and USC models to facilitate comparisons between different SBRT dose fractionations. Tumor control probability (TCP) was then estimated from the LQ- and USC-EUD_CFRT.

Results

For non-standard SBRT fractionation, the deviation of the USC- from the LQ-EUD_SBRT is largely limited to 5% in the presence of dose variation up to ±20% to fractional tumor volume up to 30% in all NSCLC cell lines. Linear regression with zero constant yielded USC-EUD_SBRT = 0.96 × LQ-EUD_SBRT (r² = 0.99) for the clinical DVHs. Converting EUD_SBRT into standard 2‑Gy fractions by the LQ formalism produced significantly larger EUD_CFRT than the USC formalism, particularly for low \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\alpha /\beta$$\end{document}α/β ratios and large fraction dose. Simplified two-compartment DVH models illustrated that both the LQ- and USC-EUD_CFRT values were sensitive to cold spot below the prescription dose with little volume dependence. Their deviations were almost constant for up to 30% dose increase above the prescription. Linear regression with zero constant yielded USC-EUD_CFRT = 1.56 × LQ-EUD_CFRT (r² = 0.99) for the clinical DVHs. The clinical LQ-EUD_CFRT resulted in median TCP of almost 100% vs. 93.8% with USC-EUD_CFRT.

Conclusion

A uniform formalism of EUD should be defined among the SBRT community in order to apply it as a single metric for dose reporting and dose–response modeling in high-dose-gradient SBRT because its value depends on the underlying cell survival model and the model parameters. Further investigations of the optimal formalism to derive the EUD through clinical correlations are warranted.

Electronic supplementary material

The online version of this article (10.1007/s00066-020-01713-w) contains supplementary material, which is available to authorized users.

Repeat Thoracic Stereotactic Body Radiation Therapy (SBRT) for Nonsmall Cell Lung Cancer: Long-Term Outcomes, Toxicity, and Dosimetric Considerations

Purpose

Lung reirradiation for nonsmall cell lung cancer (NSCLC) is common for either recurrent disease or new primary cancer. Dose volume tolerance of the lung after multiple courses of radiation therapy (RT) is unknown. We review our experience with lung reirradiation for patients with NSCLC in a single community setting using stereotactic body radiation therapy (SBRT) to report lung cumulative doses, survival, and toxicity.

Methods and Materials

Forty-four patients who received at least 2 curative courses of lung RT with the second course delivered between January 2012 and December 2017 were eligible. All patients had NSCLC and were treated with SBRT for reirradiation. Cumulative lung dose volume histograms for all courses were generated, summated, and converted into cumulative equivalent dose in 2 Gy fractions (EQD2). Actuarial overall survival (OS), local control, and toxicity is reported, including a subset of patients who received more than 2 courses of SBRT.

Results

Median age of the group was 71 years (range, 51-87). Median survival of the entire group from diagnosis, first, and second courses of RT was 3.94, 3.03, and 2.03 years. Three-year actuarial OS for the entire group was 34.1% from second course of RT. The mean EQD2 Gy₃ mean lung dose for all courses was 12.35 Gy (range, 2.7-26.52). The mean EQD2 Gy₃ V5Gy, V10Gy, V20Gy, V30Gy, and V40Gy were 40.9%, 25.5%, 14.7%, 10.2%, and 7.7%. Six-year actuarial freedom from grade ≥3 complications was 86.3%. The rate of grade ≥3 lung toxicity was 4.5% (2 of 44). Other late toxicities included grade 3 recurrent laryngeal nerve damage (n = 1) and grade 3 chest wall pain/rib fracture (n = 1). Overall, 32% of patients had more than 2 courses of RT to the lung (range, 3-7).

Conclusions

Long-term OS is possible with multiple RT courses to the lung for NSCLC with low toxicity.

Evaluation of the prognostic value of derived neutrophil/lymphocyte ratio in early stage non-small cell lung cancer patients treated with stereotactic ablative radiotherapy

The derived neutrophil-lymphocyte ration (dNLR) is a systemic inflammatory marker.The present study focusing on the prognostic value of pre-treatment dNLR in patients of early stage non-small cell lung cancer (NSCLC).From 2012 to 2016, patients with newly diagnosed early stage NSCLC were investigated. Only these who treated with stereotactic ablative radiotherapy (SABR) were enrolled in this study. dNLR was calculated from complete blood count prior to SABR. The optimal cut-off value of dNLR was determined by receiver operating curve. Kaplan-Meier curves and Cox proportional models were used to analyze the impact of pre-treatment dNLR on disease free survival (DFS) and overall survival (OS).There were 69 patients eligible for analysis, the median follow-up period was 30.9 months. Calculated by receiver operating characteristic curves, the optimal cut off value of dNLR was 1.99. Kaplan-Meier curves demonstrated that a decreased dNLR was correlated with favorable DFS and OS. In univariate analysis, high dNLR was associated with decreased survival; moreover, multivariate analysis revealed that a decreased dNLR was an independent significant favorable prognostic factor for both DFS and OS.An elevated pre-treatment dNLR may be an independent prognostic biomarker for DFS and OS in patients with early stage NSCLC that are eligible for SABR. dNLR is a reliable, inexpensive, simple, and readily available tool for risk-stratification and should be considered in daily clinical practice.

Characteristics of surgically resected non-small cell lung cancer patients with post-recurrence cure

Background

The prognosis of postoperative recurrence in patients with non‐small cell lung cancer (NSCLC) is poor. However, depending on the recurrence patterns and treatment options, some patients can achieve long‐term survival following recurrence. In this study, we investigated the clinicopathological characteristics of NSCLC patients with curable disease who developed postoperative recurrence.

Methods

This retrospective study enrolled 535 patients who had developed recurrence from among 1760 consecutive patients with NSCLC who underwent curative resection from 1990 to 2008.

Post‐recurrence cure was defined as being cancer‐free for at least five years after treatment for recurrence in patients who had undergone radical local treatment or chemotherapy. The clinicopathological characteristics associated with post‐recurrence cure were analyzed.

Results

Among 535 patients who developed recurrence, 24 (4.5%) achieved post‐recurrence cure. The median post‐recurrence follow‐up duration was 151 (85–275) months for those who achieved post‐recurrence cure. The solitary recurrent lesions and local treatment for the initial recurrence site were significantly more for patients who could be cured after they developed recurrence. All patients with post‐recurrence cure received only radical local treatment for the recurrent lesions.

Conclusions

Some patients with solitary recurrent NSCLC lesions can be cured with only radical local treatment.

Key points

Significant findings of the study

The post‐recurrence cure patients maintained a cancer‐free status for five years after treatment for recurrence without a second recurrence. All patients with post‐recurrence cure received only radical local treatment for recurrence and had significantly higher number of solitary recurrent lesions.

What this study adds

Some patients with solitary recurrent NSCLC lesions after resection can be cured with only radical local treatment.

Survival Outcomes of Salvage Therapy for Local and Regionally Recurrent NSCLC

Introduction

The treatment of locally recurrent NSCLC after initial curative therapy is variable. We sought to perform a real-world analysis of curative and palliative therapeutic strategies used in locally recurrent NSCLC and explore the impact of baseline factors and the previous and recurrent treatment on outcomes.

Methods

A retrospective cohort study was done including all patients with stage I to III NSCLC who were referred to BC Cancer and received curative-intent therapy between 2005 and 2012. Patients were followed up to determine whether they developed locoregional recurrence. Two cohorts were created: curative-intent treatment at recurrence (surgery, radiotherapy with ≥50Gy ± chemotherapy, stereotactic radiosurgery) and palliative treatment. The primary outcome was overall survival (OS).

Results

A total of 1571 patients received curative-intent therapy during the study period. Of these, 179 (11%) developed a local and regional recurrence. A total of 51 patients (28%) were treated with curative intent at recurrence (12 surgery, 39 radiotherapy ± chemotherapy), and 128 (72%) received palliative treatment only. Patients receiving curative-intent therapy were more likely to have an Eastern Cooperative Oncology Group performance status of 0 to 1 (90% versus 58%), earlier stage at diagnosis (51% stage I) and receive more aggressive staging investigations at recurrence, pathologic confirmation (75% versus 27%) and positron emission tomography (77% versus 27%). OS was longer in the cohort receiving curative-intent therapy, with an OS of 34.3 months versus 9.8 months (p < 0.001) in palliative treatment.

Conclusions

In this real-world population, isolated locoregional recurrences occurred in 11% of patients. Curative-intent treatment at recurrence is associated with a reasonable chance of long-term survival, making aggressive therapy of locoregional recurrences an important treatment consideration.

What is the role of reirradiation in the management of locoregionally relapsed non small-cell lung cancer?

The prognosis of lung cancer patients has improved in the last few years. Despite definitive therapy, local recurrence or a second primary tumour can occur in many patients within previously irradiated areas. Recent developement of more accurate techniques in radiation oncology allows delivery of high radiation dose to the tumor with the aim of improving local control, delaying disease progression and in some cases even curing. Nevertheless, the use of high dose in the reirradiation setting is not without risks, especially when treatment volumes overlap with previously irradiated tissues. The risk of adverse effects must be balanced with the choice of an effective treatment by selecting suitable candidates and the best radiation technique. In this systemic review efficacy and toxicity of reirradiation in locoregionally recurrent non-small-cell lung cancer is extensively discussed. Results indicate that reirradiation might be beneficial in well-selected patients. Prospective and high quality studies are necessary in this field.

Long-term toxicity and survival outcomes after stereotactic ablative radiotherapy for patients with centrally located thoracic tumors

Background

Stereotactic ablative radiotherapy (SABR) is effective for thoracic cancer and metastases; however, adverse effects are greater for central tumors. We evaluated factors affecting outcomes and toxicities after SABR for patients with primary lung and oligometastatic tumors.

Patients and methods

We retrospectively identified consecutive patients with centrally located lung tumors that were treated at our hospital from 2009-2016. The effects of patient, disease, and treatment-related parameters on local control (LC), overall survival (OS), and toxicity-free survival (TFS) were evaluated with multivariate analyses.

Results

Among 65 consecutive patients identified with 70 centrally located tumors, 20 tumors (28%) were reirradiated. Median (range) total dose for all tumors was 55 (30–60) Gy in 5 (3–10) fractions. Radiographic complete response was obtained in 43 lesions (61%). None of the analyzed factors were correlated with complete response. After a median follow-up of 57 (95% CI, 48–65) months, 10 tumors (14%) relapsed and 37 patients (57%) died; the actuarial 2- and 5-year OS rates were 52% and 28%, respectively. Median OS was significantly lower in patients with grade 3 or higher toxicity vs. lower toxicity (5 vs. 39 months; P < 0.001). Among 17 severe toxicities, 5 were grade 5, and 3 of them were reirradiated to the same field. Grade 3 to 5 TFS was lower with vs. without reirradiation (2-year TFS, 63% vs. 96%; P = 0.02).

Conclusions

Our study showed that modern SABR is effective for central lung tumors, and toxicities are acceptable. SABR for reirradiated central lung lesions and possibly for lesions abutting the tracheobronchial tree may result in higher risk of serious toxicities.

Effectiveness and Safety of Reirradiation With Stereotactic Ablative Radiotherapy of Lung Cancer After a First Course of Thoracic Radiation: A Meta-analysis

OBJECTIVE

The effectiveness and safety of reirradiation with stereotactic ablative radiotherapy (re-SABR) in patients with recurrence after a previous course of radiation are limited to small series. We carried out a meta-analysis to summarize existing data and identify trends in overall survival (OS), local control (LC), and toxicity after re-SABR in patients with recurrence of lung cancer.

MATERIALS AND METHODS

Eligible studies were identified on Medline, Embase, the Cochrane Library, and the proceedings of annual meetings through June 2019. We followed the PRISMA and MOOSE guidelines. A meta-regression analysis was carried out to assess whether there is a relationship between moderator variables and outcomes. A P-value<0.05 was considered significant.

RESULTS

Twenty observational studies with a total of 595 patients treated were included. The 2-year OS and LC were 0.54 (95% confidence interval [CI]: 0.48-0.61) and 0.73 (95% CI: 0.66-0.80), respectively. The rate of any toxicity grade ≥3 was 0.098 (95% CI: 0.06-13.6), with 9 grade 5 toxicity (1.5%). In the meta-regression, the re-SABR dose (P=0.028), tumor size (P=0.031), and time to recurrence (P=0.018) showed an association with survival. For LC, the re-SABR dose (P=0.034) and tumor size (P=0.040) were statistically significant. Any toxicity grade ≥3 showed a relationship with the cumulative dose (P=0.024). Cumulative dose ≤145 versus >145 Gy2 had 3% versus 15% (P=0.013) of any grade ≥3 toxicity.

CONCLUSIONS

Re-SABR produces satisfactory LC and OS rates with an acceptable rate of toxicity. The balancing between the re-SABR dose and the tumor location has the potential to reduce severe and fatal toxicity.

Challenges in Re-Irradiation in the Thorax: Managing Patients with Locally Recurrent Non-Small Cell Lung Cancer

Treatment of locally recurrent non-small lung cancer (NSCLC) after definitive chemoradiation therapy is challenging as patients are often inoperable and systemic therapy alone frequently results in suboptimal outcomes. Re-irradiation of NSCLC may be the best strategy for treating locoregional failures with the goal of durable long-term control and potentially cure. Repeat irradiation is technically challenging for fear of life-threatening toxicities to previously irradiated organs at risk while also delivering definitive doses of radiation to recurrent disease. No standard guidelines exist with regards to re-irradiation technique and re-treatment dose constraints to organs at risks. We herein describe a case of locoregional recurrence after definitive chemoradiation therapy for NSCLC with expert opinions for subsequent management. As described and guided by our experts, we review the various techniques for repeat radiation therapy, treatment planning goals, and reported toxicities and outcomes in the re-irradiation setting.

Oncologic Outcomes of Surgery Versus SBRT for Non-Small-Cell Lung Carcinoma: A Systematic Review and Meta-analysis

BACKGROUND

The optimal treatment of stage I non-small-cell lung carcinoma is subject to debate. The aim of this study was to compare overall survival and oncologic outcomes of lobar resection (LR), sublobar resection (SR), and stereotactic body radiotherapy (SBRT).

METHODS

A systematic review and meta-analysis of oncologic outcomes of propensity matched comparative and noncomparative cohort studies was performed. Outcomes of interest were overall survival and disease-free survival. The inverse variance method and the random-effects method for meta-analysis were utilized to assess the pooled estimates.

RESULTS

A total of 100 studies with patients treated for clinical stage I non-small-cell lung carcinoma were included. Long-term overall and disease-free survival after LR was superior over SBRT in all comparisons, and for most comparisons, SR was superior to SBRT. Noncomparative studies showed superior long-term overall and disease-free survival for both LR and SR over SBRT. Although the papers were heterogeneous and of low quality, results remained essentially the same throughout a large number of stratifications and sensitivity analyses.

CONCLUSION

Results of this systematic review and meta-analysis showed that LR has superior outcomes compared to SBRT for cI non-small-cell lung carcinoma. New trials are underway evaluating long-term results of SBRT in potentially operable patients.

Salvage stereotactic body radiotherapy for post-operative oligo-recurrence of non-small cell lung cancer: A single-institution analysis of 59 patients

A standard treatment for patients with early-stage non-small cell lung cancer (NSCLC) who undergo surgery, and subsequently develop local failure or intrathoracic oligo-recurrence, has not yet been established. The present study aimed to assess the feasibility of stereotactic body radiotherapy (SBRT) for this subgroup of patients. Consequently, a retrospective analysis was conducted of patients with NSCLC recurrence who were treated with SBRT, and previously underwent curative surgical resection between October 2011 and October 2016. Post-SBRT survival [overall survival (OS); progression-free survival (PFS); and local control (LC)] and toxicity were analyzed. Prognostic factors for OS were identified using univariate and multivariate analysis. A total of 52 patients and 59 tumors were analyzed. The median follow-up time was 25 months (35 months for surviving patients), and median OS following salvage SBRT was 32 months. The 1- and 3-year OS rates were 84.4 and 67.8%, respectively. 1- and 3-year PFS rates were 80.8 and 58.7%, respectively. Only 4 patients (7.7%) developed local failure. Median LC was 71 months and 1- and 3-year LC rate were 97.9 and 94.9%, respectively. A total of 4 patients experienced grade 3 or higher adverse events (AEs) and two experienced grade 5 AEs (pneumonitis and hemoptysis). Central tumor location and the possibility of re-operation were independent prognostic factors for OS. The present study indicated that post-operative salvage SBRT is a promising therapeutic option for patients with NSCLC with locoregional or intrathoracic oligo-recurrence. We regard toxicity was also acceptable. However, further research is required on the appropriate selection of subjects, and stratification of the analysis by certain risk factors would increase the accuracy of the conclusions.

Salvage Therapy for Locoregional Recurrence After Stereotactic Ablative Radiotherapy for Early-Stage NSCLC

Although isolated local (LRs) and regional recurrences (RRs) constitute a minority of post-stereotactic ablative radiotherapy (SABR) relapses, their management is becoming increasingly important as the use of SABR continues to expand. However, few evidence-based strategies are available to guide treatment of these potentially curable recurrences. On behalf of the Advanced Radiation Technology Committee of the International Association for the Study of Lung Cancer, this article was written to address management of recurrent disease. Topics discussed include diagnosis and workup, including the roles of volumetric and functional imaging as well as histopathologic methods; clinical outcomes after salvage therapy; patterns of recurrence after salvage therapy; and management options. Our main conclusions are that survival for patients with adequately salvaged LRs is similar to that for patients after primary SABR without recurrence, and survival for those with salvaged RRs (regardless of nodal burden or location) is similar to that of patients with de novo stage III disease. Although more than half of patients who undergo salvage do not develop a second relapse, the predominant pattern of second failure is distant, especially for RRs. Management requires rigorous multidisciplinary coordination. Isolated LRs can be managed with resection and nodal dissection, repeat SABR, thermal ablation, or systemic therapies. RRs can be treated with combined chemoradiotherapy, radiation or chemotherapy alone, or supportive services. Finally, regular and structured follow-up is recommended after post-SABR salvage therapy.

Management of local recurrences and regional failure in early stage non-small cell lung cancer after stereotactic body radiation therapy

Stereotactic body radiation therapy (SBRT) is a very effective way to treat early stage non-small cell lung cancer (NSCLC) and small oligometastatic lung lesions with consistently high rates of local control, but both local and regional/distant recurrences still occur. The management of recurrences remains unsettled and may entail repeat SBRT, conventionally fractionated external beam RT (EF-EBRT), chemotherapy or surgery. Most patients with local recurrences [within the initial planning target volume (PTV)] can be salvaged successfully with good cancer specific survival. Nonetheless, proximity of the initial SBRT delivery to organs at risk (ribs, blood vessels, airways) may make retreatment more difficult. With attention to detail and careful patient selection, both surgery and reirradiation can be performed safely and effectively. Strategies for management of regional (nodal) recurrences may require conventional therapies tailored to the patterns of failure. The role of immunotherapy in salvage has not been elucidated as yet. We review here data on the available literature concerning salvage of SBRT lung patients.

Stereotactic Ablative Radiation Therapy for Pulmonary Recurrence-Based Oligometastatic Non-Small Cell Lung Cancer: Survival and Prognostic Value of Regulatory T Cells

PURPOSE

We evaluated survival of patients with pulmonary recurrence-based oligometastatic non-small cell lung cancer (NSCLC) whose lesions were all treated with stereotactic ablative radiation therapy (SABR) and the prognostic value of peripheral immune cells.

METHODS AND MATERIALS

In this prospective observational cohort study, we prospectively enrolled 63 patients with oligometastatic NSCLC, for whom all metastases were treated with SABR. Peripheral blood samples were collected 3 days before treatment began, and flow cytometry was used to identify proportions of regulatory T cells (Tregs; CD4+CD25+CD127^low), B cells, NK cells, γδT cells, CD8+CD28+ T cells, and CD8+CD28- T cells. Overall survival (OS) and progression-free survival (PFS) was estimated by the Kaplan-Meier method, and the potential prognostic value of clinicopathologic factors was evaluated by Cox proportional hazards regression.

RESULTS

At a median follow-up time of 19.1 months, estimated OS rates were 84.3% at 1 year, 63.4% at 2 years, and 44.0% at 3 years; corresponding PFS rates were 55.2%, 30.9%, and 25.7%. Estimated local control rates were 96.7% at 1 year and 92.7% at both 2 years and 3 years. Patients with high numbers of Tregs had poorer OS and PFS than did those with low numbers of Tregs (OS: 16.1 months vs not reached, P = .006; PFS: 11.0 vs 21.7 months, P = .013). Treg level was found to be an independent predictor of both OS and PFS in multivariate analyses (OS: hazard ratio 2.68, P = .038; PFS: hazard ratio 2.35, P = .011).

CONCLUSIONS

Our results revealed the independent prognostic value of Tregs in patients treated with SABR for pulmonary recurrence-based oligometastatic NSCLC. Additional treatments may be needed for patients with oligometastatic NSCLC and poor outcomes.

Peripheral memory and naïve T cells in non-small cell lung cancer patients with lung metastases undergoing stereotactic body radiotherapy: predictors of early tumor response

Background

Further analysis of phase I trial of the KEYNOTE-001 has shown that previous radiotherapy improves the outcomes of patients with advanced non-small cell lung cancer (NSCLC) who received pembrolizumab treatment, possibly explained by the radiation-induced specific anti-cancer immunity with a memory effect. In this study, we aimed to investigate the peripheral memory and naïve T cells as predictors of early response in lung metastases post-stereotactic body radiotherapy (SBRT).

Methods

Sixty-six lung metastases patients with NSCLC who received SBRT were enrolled in this study. Analyses of peripheral memory CD4+ T, memory CD8+ T, naive CD4+ T, and naive CD8+ T in NSCLC patients were performed by flow cytometry. Evaluations of the link between immune cells and early radiation response a month after SBRT were carried out via logistic regression analyses.

Results

Higher levels of memory CD4+ T, memory CD8+ T, and lower levels of naïve CD4+ T, CD4+ naïve/memory ratio, and CD8+ naïve/memory ratio were shown in responders compared with non-responders (all P < 0.05). Logistic regression analyses of univariate and multivariate revealed that peripheral memory CD4+ T (OR: 0.14, 95% CI 0.04–0.50, P = 0.003; OR: 0.17, 95% CI 0.05–0.66, P = 0.010), memory CD8+ T (OR: 0.11, 95% CI 0.01–0.87, P = 0.037; OR: 0.11, 95% CI 0.01–0.97, P = 0.047), naïve CD4+ T (OR: 16.25, 95% CI 3.17–83.13, P = 0.001; OR: 12.67, 95% CI 2.26–71.18, P = 0.004) and CD4+ naïve/memory ratio (OR: 11.27, 95% CI 2.67–47.58, P = 0.001; OR: 8.50, 95% CI 1.90–38.14, P = 0.005) were independent predictors for tumor response to SBRT in the lung metastases of NSCLC patients.

Conclusions

The tumor response of lung metastases a month after SBRT independently correlated with peripheral memory CD4+ T, memory CD8+ T, naïve CD4+ T, and CD4+ naïve/memory ratio. These findings could be helpful in incorporating additional treatments to improve clinical outcomes in the case of poor responders.

Electronic supplementary material

The online version of this article (10.1186/s12935-019-0839-5) contains supplementary material, which is available to authorized users.

Increased CD8+CD28+ T cells independently predict better early response to stereotactic ablative radiotherapy in patients with lung metastases from non-small cell lung cancer

Background

Stereotactic ablative radiotherapy (SABR) shows a remarkable local control of non-small cell lung cancer (NSCLC) metastases, partially as a result of host immune status. However, the predictors of immune cells for tumor response after SABR are unknown. To that effect, we investigated the ability of pre-SABR immune cells in peripheral blood to predict early tumor response to SABR in patients with lung metastases from NSCLC.

Methods

This study included 70 patients with lung metastases from NSCLC who were undergoing SABR. We evaluated the early tumor response 1 month and 6 months after SABR in these patients following RECIST 1.1 guidelines. Pre-SABR peripheral CD8+ T cell count, CD8+CD28+ T-cell count, CD8+CD28− T-cell count, CD4+ T-cell count, and Treg-cell count were measured using flow cytometry.

Results

Increased CD8+CD28+ T-cell counts (14.43 ± 0.65 vs. 10.21 ± 0.66; P = 0.001) and CD4/Treg ratio (16.96 ± 1.76 vs. 11.91 ± 0.74; P = 0.011) were noted in 1-month responsive patients, compared with non-responsive patients. In univariate logistic analyses, high CD8+CD28+ T-cell counts (OR 0.12, 95% CI 0.03–0.48; P = 0.003), CD4/Treg ratio (OR 0.24, 95% CI 0.06–0.90; P = 0.035), and BED₁₀ (OR 0.91, 95% CI 0.84–0.99; P = 0.032) predicted a 1-month tumor response to SABR. According to multivariate logistic analyses, the CD8+CD28+ T-cell count predicted a 1-month tumor response to SABR (OR 0.19, 95% CI 0.04–0.90; P = 0.037) independently. Furthermore, we confirmed the independent predictive value of the CD8+CD28+ T-cell count in predicting tumor response to SABR in 41 patients 6 months after treatment (OR 0.08, 95% CI 0.01–0.85; P = 0.039).

Conclusions

A pre-SABR CD8+CD28+ T-cell count could predict early tumor response to SABR in patients with lung metastases from NSCLC. Larger, independently prospective analyses are warranted to verify our findings.

Electronic supplementary material

The online version of this article (10.1186/s12967-019-1872-9) contains supplementary material, which is available to authorized users.

Stereotactic body radiotherapy in patients with chronic obstructive pulmonary disease and interstitial pneumonia: a review

Stereotactic body radiation therapy (SBRT) can yield excellent local tumor control, as well as survival benefit comparable to that of surgery for early-stage lung cancer. However, in terms of toxicity, SBRT might lead to fatal radiation pneumonitis. Lung diseases, such as chronic obstructive pulmonary disease (COPD) and interstitial lung disease (ILD), are major risk factors for lung cancer. However, these patients are typically not candidates for the gold-standard treatment option, lobectomy, because of the perioperative risks. In addition, patients with poor respiratory function can be excluded in prospective clinical trials. Thus, SBRT for patients with pulmonary diseases is still challenging, but there appears to be a clinical role for this modality as an alternative treatment. However, there are few well-documented review articles on SBRT for patients with pulmonary diseases. Therefore, we aimed to review SBRT in the context of important patient-related factors, including COPD and ILD. SBRT is an acceptable alternative treatment option for patients with lung cancer who also have COPD with an equivalent risk of radiation pneumonitis to normal lung. However, latent ILD should be detected prior to treatment. The indication for SBRT should be decided by carefully considering the risks and benefit for patients with ILD.

Chest Wall Toxicity After Stereotactic Body Radiation Therapy: A Pooled Analysis of 57 Studies

PURPOSE

The significance of clinical and dosimetric risk factors in relation to chest wall (CW) injury after stereotactic body radiation therapy (SBRT) for lung tumors were analyzed through a meta-analysis of 57 published studies.

METHODS AND MATERIALS

Studies related to CW injury after lung SBRT were obtained through searching PubMed, Embase, and Cochrane electronic databases. An estimate of the incidence of CW pain (CWP) or rib fracture (RF) was derived using a Bayesian hierarchical model. Linear regression analysis was performed to assess the relationship between CWP or RF and clinical or dosimetric factors.

RESULTS

A total of 57 studies incorporating 5985 cases reporting clinical data on CW injury after SBRT were analyzed. The overall CWP and RF rates by Bayesian hierarchical modeling were 11.0% (95% confidence interval [CI], 8.0-14.4) and 6.3% (95% CI, 3.7-9.7), respectively. The rates of grade ≥2 and grade ≥3 CWP were 6.2% (95% CI, 3.88-8.93) and 1.2% (95% CI, 0.48-2.12), respectively. Sex was significantly correlated with RF (P < .001), with female patients having a greater risk of RF than male patients (hazard ratio = 0.59; 95% CI, 0.46-0.76). No correlation was found between RF, grade ≥2 CWP, or grade ≥3 CWP, with the clinical and dosimetric factors of age, tumor size, origin of lung tumor, gross tumor volume, planning target volume, fractional dose, number of fractions, or biologically effective dose. However, tumor to CW distance (<16-25 mm), body mass index, maximum dose (Dmax) of 0.5 to 5 cm³, and the volume of CW or ribs receiving >30 Gy were significantly associated with CWP and RF.

CONCLUSIONS

The overall rates of RF and grade ≥2 CWP after thoracic SBRT are relatively low. Sex, tumor to CW distance, maximum dose, and the radiation exposure of the CW or ribs are factors associated with the risk of CW toxicity after SBRT.

Lobectomy vs. segmentectomy. A propensity score matched comparison of outcomes

BACKGROUND

Segmentectomy has emerged as a lung parenchymal sparring alternative to the gold standard lobectomy in non-small cell lung cancer (NSCLC) patients. We hypothesized that there is parity between functional, local recurrence and survival outcomes.

PATIENTS AND METHODS

Parenchymal sparring procedures including anatomical segmentectomies were propensity score matched 1:1 with lobectomies (n = 64). The primary outcomes included survival, functional and oncological outcomes. The oncological outcomes were: post-operative histology, clear margins and local recurrence rates. Kaplan Meier survival curves were used to compare the survival. Oncological and functional variables were assessed by Fischer exact test and t-test.

RESULTS

The pre-operative performance status, ASA grade, lung function, risk factors, surgical approach and tumour histology were similar between the groups. The tumour size was significantly higher for lobectomies (32.4 ± 17 vs. 24.6 ± 12 mm, p = 0.01). The tumour staging in the segmentectomy group was similar to the lobectomy group (Ia; 50 vs. 34%; Ib: 29 vs. 37%; IIa 11 vs. 9.3%; IIb 5 vs. 14%; IIIa 5 vs. 4.6%, p = 0.83). The loco-regional recurrence was lower in the segmentectomy group (1.5 vs. 3.1%, p = 0.69). The up-staging and down-staging post-surgery was similar in both groups, while neo-adjuvant therapy was used in 5 lobectomy and 3 segmentectomy cases. The survival was similar at 1 year between the groups (88 vs. 92%, p = 0.65). Between 4 and 5 years, the survival reduced in the parenchymal sparing group to 39% vs. 68% in the lobectomy group (p = 0.04).

CONCLUSION

Surgical selection bias could be an important confounder in the selection of patients undergoing segmentectomy. Similar up and down staging were demonstrated in the two groups. This is one of the first studies to investigate the results of segmentectomy versus lobectomy in stage II/IIIa NSCLC tumours. No significant differences were found in functional outcomes, but the survival decreased after 4 years in the segmentectomy group, which could be explained by lower survival in the stage II/IIIa tumours treated with segmentectomy.

Association of Long-term Outcomes and Survival With Multidisciplinary Salvage Treatment for Local and Regional Recurrence After Stereotactic Ablative Radiotherapy for Early-Stage Lung Cancer

Importance

Stereotactic ablative radiotherapy (SABR) is first-line treatment for patients with early-stage non-small cell lung cancer (NSCLC) who cannot undergo surgery. However, up to 1 in 6 such patients will develop isolated local recurrence (iLR) or isolated regional recurrence (iRR). Little is known about outcomes when disease recurs after SABR, or about optimal management strategies for such recurrences.

Objective

To characterize long-term outcomes for patients with iLR or iRR after SABR for early-stage NSCLC with the aim of informing treatment decision making for these patients with potentially curable disease.

Design, Setting, and Participants

In this cohort study, a retrospective review was conducted of 912 patients prospectively enrolled in an institutional database at a tertiary cancer center from January 1, 2004, through December 31, 2014.

Main Outcomes and Measures

Overall survival, progression-free survival, recurrence patterns, demographics, salvage techniques, patterns of salvage failure, and toxic effects.

Results

Of the 912 patients in the study (456 women and 456 men; median age, 72 years [range, 46-91 years]), 756 (82.9%) had T1 tumors at initial diagnosis; 502 tumors (55.0%) were adenocarcinomas and 309 tumors (33.9%) were squamous cell carcinomas. Of 912 patients with early-stage I to II NSCLC who received definitive SABR (50 Gy in 4 fractions or 70 Gy in 10 fractions), 102 developed isolated recurrence (49 with iLR and 53 with iRR), and 658 had no recurrence. Median times to recurrence after SABR were 14.5 months (range, 1.5-60.8 months) for iLR and 9.0 months (range, 1.9-70.7 months) for iRR; 39 of 49 patients (79.6%) with iLR and 48 of 53 patients (90.6%) with iRR underwent salvage with reirradiation, surgery, thermal ablation, or chemotherapy. Median follow-up times for patients with iLR or iRR were 57.2 months (interquartile range, 37.7-87.6 months) from initial SABR and 38.5 months (interquartile range, 19.9-69.3 months) from recurrence. Rates of overall survival at 5 years from initial SABR were no different between patients with iLR and salvage treatment (57.9%) and patients with no recurrence (54.9%; hazard ratio, 0.89; 95% CI, 0.56-1.43; P = .65) but were lower for patients with iRR and salvage treatment (31.1%; hazard ratio, 1.43; 95% CI, 1.00-2.34; P = .049). Patients receiving salvage treatment had longer overall survival than patients who did not (median, 37 vs 7 months after recurrence; hazard ratio, 0.40; 95% CI, 0.09-0.66; P = .006). Twenty-four of 87 patients (27.6%) who received salvage treatment for iLR or iRR subsequently developed distant metastases. No patient experienced grade 5 toxic effects after salvage treatment.

Conclusions and Relevance

Life expectancy after salvage treatment for iLR was similar to that for patients without recurrence, but survival after salvage treatment for iRR was similar to that of patients with stage III NSCLC. Patients who received salvage treatment had significantly improved survival. Because salvage treatment for iLR or iRR was based on a consistent multidisciplinary approach, this may help in clinical decision making.

Stereotactic body radiotherapy (SBRT) for Stage I lung cancer

Stereotactic body radiation therapy (SBRT) is a newly developed technique currently in clinical use. SBRT originated from stereotactic radiosurgery (SRS) for intracranial tumors. Since the 1990s, SBRT has been widely used in clinical settings for the treatment of lung cancer. We review the history and current standard techniques. Previous clinical studies of lung cancer showed high local control rates with acceptable toxicities. Past and on-going clinical trials are also reviewed.

Stereotactic Body Radiotherapy for Early-Stage Non-Small-Cell Lung Cancer: American Society of Clinical Oncology Endorsement of the American Society for Radiation Oncology Evidence-Based Guideline

Purpose The American Society for Radiation Oncology (ASTRO) produced an evidence-based guideline on treatment with stereotactic body radiotherapy (SBRT) for patients with early-stage non-small-cell lung cancer. ASCO has a policy and set of procedures for endorsing and/or adapting clinical practice guidelines that have been developed by other professional organizations. Methods The ASTRO Evidence-Based Guideline for Stereotactic Body Radiotherapy for Early-Stage Non-Small-Cell Lung Cancer was reviewed for developmental rigor by methodologists. An ASCO Expert Panel updated the literature search and reviewed the guideline content and recommendations. Results The ASCO Expert Panel determined that the recommendations from the ASTRO guideline, published in 2017, are clear, thorough, and based on the most relevant scientific evidence. ASCO statements and minor modifications were added to enhance the applicability of the ASTRO guideline for the broader ASCO audience. Recommendations For standard operative risk patients with stage I NSCLC, SBRT is not recommended outside of a clinical trial. Lobectomy with systematic lymph node evaluation remains the recommended treatment, although a sublobar resection may be considered in select clinical scenarios. Recommendations are provided regarding the use of SBRT in high operative risk patients and for inoperative patients, including in challenging scenarios where tumors are: centrally located, > 5 cm in diameter, lacking tissue diagnosis, synchronous primary or multifocal, second primary after pneumonectomy, proximal to or involved with mediastinal structures, abutting the chest wall, or recurring after previous treatment. Qualifying statements are included to provide further guidance for implementation, and the importance of a discussion of treatment options among members of the multidisciplinary cancer care team is emphasized. Additional information is available at: www.asco.org/thoracic-cancer-guidelines and www.asco.org/guidelineswiki .

Stereotactic body radiotherapy as salvage treatment for recurrence of non-small cell lung cancer after prior surgery or radiotherapy

Treatment options for thoracic recurrences of non-small cell lung cancer (NSCLC) are limited. Stereotactic body radiation therapy (SBRT) is an emerging, potentially effective technology to manage recurrent NSCLC, although with limited prospective studies. This work reviews the outcomes of patients undergoing salvage SBRT for pulmonary recurrences after prior resection or prior radiotherapy for NSCLC. Following salvage SBRT, after prior external beam radiation (SBRT or conventionally fractionated), the 2-year overall survival (OS) ranged from 37% to 79% in 11 of the studies (397 patients) reviewed here, while the 2-year local control (LC) ranged from 37% to 90% in 6 studies that reported that outcome. Toxicity risks are acceptable albeit with appreciable risks of severe to potentially fatal toxicity, necessitating the need to weigh risks vs. benefits in the re-irradiation setting. There were fewer studies on the use of SBRT after prior resection. Following salvage SBRT, after prior resection, the 2-year OS ranged from 56% to 68% in 4 studies (131 patients) reviewed here, while the 2-year LC ranged from 83% to 100% in 3 of these studies. SBRT in the salvage setting after prior resection appeared to be well-tolerated, with toxicity risks comparable to historical patients treated with SBRT alone (i.e., SBRT without prior resection, which is not reviewed here). The data are limited due to the retrospective nature of published studies (all but 4 with <40 patients), with various clinical scenarios (i.e., original NSCLC stage, prior treatment, location of target amenable to salvage SBRT) and a range of SBRT dosing and techniques. More studies are needed to better understand the tumor control, survival and toxicity of SBRT for salvage therapy of NSCLC patients, as well as the potentially prognostic factors that could affect these outcomes.