Consolidative Local Ablative Therapy Improves the Survival of Patients With Synchronous Oligometastatic NSCLC Harboring EGFR Activating Mutation Treated With First-Line EGFR-TKIs. J Thorac Oncol. 2018;13:1383-1392. [PMID: 29852232 DOI: 10.1016/j.jtho.2018.05.019]

The use of radiation therapy for oligoprogressive/oligopersistent oncogene-driven non small cell lung cancer: State of the art

Oncogene-driven non small cell lung cancer (NSCLC) is a distinct entity in thoracic oncology. The availability of effective target therapies, like EGFR inhibitors or ALK inhibitors, have revolutionized the prognosis of these patients. However, despite an initial response in the majority of patients, drug resistance ultimately occurs. In some cases, this resistance develops in few clonal cells (oligoprogression), so that a local ablation of these resistant deposits could allow to maintain the same systemic therapy and possibly to prolong patients' survival. For these purposes, stereotactic body radiation therapy (SBRT) is an ideal local ablative treatment, because it is effective, non invasive and with limited side effects. In this review, we aim to analyze available clinical data to verify whether SBRT can allow these patients to continue with existing target therapy longer, delay the switch to other systemic therapies and improve their outcome modifying the natural history of the disease.

Patient-Reported Outcomes of Oligometastatic Patients After Conventional or Stereotactic Radiation Therapy to Bone Metastases: An Analysis of the PRESENT Cohort

PURPOSE

Stereotactic body radiation therapy (SBRT) has become a widely adopted treatment for patients with oligometastatic disease, despite limited evidence of superiority. We compared pain response and quality of life (QoL) in patients with oligometastatic disease treated with conventionally fractionated 3-dimensional radiation therapy (3DCRT) or SBRT to bone metastases.

METHODS AND MATERIALS

We included patients with oligometastatic disease (≤5 lesions within ≤3 organs) treated within the prospective PRESENT cohort. Main outcomes were pain response, clinical local control, and QoL 2, 4, and 8 weeks and 3, 6, and 12 months after treatment. Pain response was assessed only in patients who reported pain at baseline and was defined according to international consensus criteria.

RESULTS

Of 131 patients with oligometastatic disease, 66 patients were treated with 3DCRT and 65 patients with SBRT. A pain response was achieved in 81% (3DCRT) versus 84% (SBRT) with a median duration of 23 weeks (range, 1-58) and 24 weeks (range, 0-50), respectively. Reirradiation was needed in 33% versus 5% of the patients, respectively. None of the QoL subscales were significantly different between both groups.

CONCLUSIONS

In patients with oligometastatic disease, SBRT to bone metastases did not improve pain response or QoL compared with 3DCRT. Reirradiation was less often needed in the SBRT group.

Pattern of Recurrence Analysis in Metastatic EGFR-Mutant NSCLC Treated with Osimertinib: Implications for Consolidative Stereotactic Body Radiation Therapy

PURPOSE

Despite the impressive response rate to osimertinib, acquired resistance remains an obstacle to achieving long-term tumor control in metastatic epidermal growth factor receptor-mutant non-small cell lung cancer. Stereotactic body radiation therapy (SBRT) plays a growing role in the management of oligometastatic disease. We investigated the patterns of residual disease and progression on osimertinib, as well as the predictors of candidates for consolidative SBRT.

METHODS AND MATERIALS

The serial scans of patients with metastatic epidermal growth factor receptor-mutant non-small cell lung cancer treated with osimertinib were retrospectively reviewed. Disease progression in residual sites, new sites, and both residual and new sites were classified as residual-site recurrence (RR), new-site recurrence (NR), and combined RR and NR (RNR), respectively. Logistic regression analysis was performed to identify predictors of candidates for consolidative SBRT.

RESULTS

Ninety-seven patients were enrolled. The median time to maximal osimertinib response was 2.6 months. Twenty-six patients (26.8%) with oligoresidual disease were identified as candidates for consolidative SBRT at time of maximal response. Stage T1-2 before initiation of osimertinib (P = .046) was the independent predictor of consolidative SBRT eligibility. During a median follow-up of 10.9 months, disease progression was documented in 50 (51.5%) patients, and 70% of them experienced oligoprogression. Twenty-five (50%) patients developed disease progression in originally involved sites, 11 (22%) had new metastases, and 14 (28%) experienced disease progression in both original and new metastatic sites. Forty-six patients had progressive disease after experiencing initial stable disease or objective response to osimertinib. RR occurred in 20 (43.5%) of these patients, NR in 14 (30.4%), and RNR in 12 (26.1%). Notably, within the subgroup of patients eligible for consolidative SBRT, RR was observed in 6 (54.5%) patients, RNR in 3 (27.3%), and NR in 2 (18.2%).

CONCLUSIONS

The majority of progressive disease on osimertinib was within residual lesions in initially involved sites. Consolidative SBRT may prolong time to progression in a selected subgroup of patients, which merits further investigation.

Is there an oligometastatic state in pancreatic cancer? Practical clinical considerations raise the question

OBJECTIVES

To evaluate the role of stereotactic body radiotherapy (SBRT) as a local ablative treatment (LAT) in oligometastatic pancreatic cancer.

METHODS

Patients affected by histologically confirmed stage IV pancreatic adenocarcinoma were included in this analysis. Endpoints are local control (LC), progression-free survival (PFS), and overall survival (OS).

RESULTS

From 2013 to 2017, a total of 41 patients were treated with SBRT on 64 metastases. Most common sites of disease were lung (29.3%) and liver (56.1%). LC at 1 and 2 years were 88.9% (95% CI 73.2-98.6) and 73.9% (95% CI 50-87.5), respectively. Median LC was 39.9 months (95% CI 23.3-not reached).PFS rates at 1 and 2 years were 21.9% (95% CI 10.8-35.4) and 10.9% (95% CI 3.4-23.4), respectively. Median PFS was 5.4 months (95%CI 3.1-11.3).OS rates at 1 and 2 years were 79.9% (95% CI 63.7-89.4) and 46.7% (95% CI 29.6-62.2). Median OS was 23 months (95%CI 14.1-31.8).

CONCLUSIONS

Our results, although based on a retrospective analysis of a small number of patients, show that patients with oligometastatic pancreatic cancer may benefit from local treatment with SBRT. Larger studies are warranted to confirm these results.

ADVANCES IN KNOWLEDGE

Selected patients affected by oligometastatic pancreatic adenocarcinoma can benefit from local ablative approaches, like SBRT.

Separating or combining immune checkpoint inhibitors (ICIs) and radiotherapy in the treatment of NSCLC brain metastases

With the advancement of imaging technology, systemic disease control rate and survival rate, the morbidity of brain metastases (BMs) from non-small cell lung cancer (NSCLC) has been riding on a steady upward trend (40%), but management of BMs from NSCLC remains obscure. Systemic therapy is anticipated to offer novel therapeutic avenues in the management of NSCLC BMs, and radiotherapy (RT) and immunotherapy have their own advantages. Recently, it was confirmed that immune checkpoint inhibitors (ICIs) and RT could mutually promote the efficacy in the treatment of BMs from NSCLC. In this paper, we provide a review on current understandings and practices of separating or combining ICIs and RT, which could provide a reference for the coming laboratory and clinical studies and contribute to the development of new approaches in NSCLC BMs.

Patterns and risks of postoperative recurrence in completely resected EGFR-mutant non-small cell lung cancer: prognostic significance of routine immunohistochemical markers

Background

Recent studies indicate that EGFR-mutant non-small cell lung cancer (NSCLC) is a heterogeneous disease with varying prognosis. In order to design an optimized surveillance strategy and identify potential candidates for adjuvant therapy, the patterns and risks of postoperative recurrence in completely resected EGFR-mutant NSCLC should be investigated, which are currently largely unknown.

Methods

Consecutive patients with curatively resected EGFR-positive NSCLC receiving standard adjuvant chemotherapy without EGFR tyrosine kinase inhibitors (TKI), with or without adjuvant radiotherapy, from January 2007 to December 2017 in our cancer center, were retrospectively reviewed. Prognostic significance of ten routine immunohistochemical (IHC) markers were examined.

Results

After a median follow-up of 32 (range, 5-122) months, disease recurrence occurred in 197 (37.1%) of the 531 enrolled patients. The frequencies of thoracic recurrence, brain recurrence, bone recurrence, abdominal recurrence and neck recurrence, were 69.0%, 20.8%, 20.8%, 7.1% and 6.6%, respectively. Using the Cox regression model, tumor size, Ki67, CK20, and N stage were identified as independent predictors of overall recurrence. A nomogram predicting the 1-, 2-, and 3-year cumulative rate of overall recurrence was then developed and internally validated, with a bias-corrected C-index of 0.723 (95% CI, 0.675 to 0.771) and a small extent of "over-fitting" (0.8%). Risk factors of site-specific recurrence were also discovered. Additionally, using competing risk analyses, N stage, lymphovascular invasion (LVI) and CK5/6 were found as independent predictors of loco-regional recurrence. Among patients with N2-positive disease (n=91), adjuvant radiotherapy tended to prolong disease free survival (DFS) (P=0.067), but not overall survival (OS) (P=0.271).

Conclusions

This study provides the proof of concept of using routine IHC markers, along with common clinical-pathological parameters, in predicting postoperative recurrence among completely resected EGFR-mutant NSCLC. Adjuvant radiotherapy may improve DFS, but hard to prolong OS in N2-positive EGFR-mutant NSCLC without further biomarker-guided patients' selection.

Management of oligometastatic non-small cell lung cancer patients: Current controversies and future directions

Oligometastatic non-small cell lung cancer (NSCLC) describes an intermediate stage of NSCLC between localized and widely-disseminated disease. This stage of NSCLC is characterized by a limited number of metastases and a more indolent tumor biology. Currently, the management of oligometastatic NSCLC involves radical treatment (radiotherapy or surgery) that targets the metastatic lesions and the primary tumor to achieve disease control. This approach offers the potential to achieve prolonged survival in patients who, in the past, would have only received palliative measures. The optimal therapeutic strategies for the different scenarios of oligometastatic disease (intracranial vs extracranial disease, synchronous vs metachronous) remain undefined. Given the lack of head-to-head studies comparing radiotherapy to surgery in these patients, the decision to apply surgery or radiotherapy (with or without systemic treatment) must be based on prognostic factors that allow us to classify patients. This classification will allow us to select the most appropriate therapeutic strategy on an individualized basis. In the future, the molecular or microRNA profiles will likely improve the treatment selection process. The objective of the present article is to review the most relevant scientific evidence on the management of patients with oligometastatic NSCLC, focusing on the role of radiotherapy and surgery. We also discuss areas of controversy and future directions.

Microwave ablation as local consolidative therapy for patients with extracranial oligometastatic EGFR-mutant non-small cell lung cancer without progression after first-line EGFR-TKIs treatment

OBJECTIVES

Evidence from multiple clinical trials showed that local consolidative therapy (LCT) improved survival in oligometastatic non-small cell lung cancer (NSCLC) patients. In the present study, we aim to explore the potential role of microwave ablation (MWA) as LCT for epidermal growth factor receptor (EGFR)-mutant advanced NSCLC patients with extracranial oligometastasis.

MATERIALS AND METHODS

From January 2015 to December 2018, a total of 86 EGFR-mutant stage IIIB or IV NSCLC patients with extracranial oligometastasis were enrolled for retrospective analysis. MWA was used as LCT for all oligometastatic lesions and/or primary tumors in 34 patients without progression after first-line EGFR-TKIs therapy (consolidation group), while the other 52 patients received only TKIs until disease progression (monotherapy group). We calculated and compared the progression-free survival (PFS) and overall survival (OS) of the two groups.

RESULTS AND CONCLUSION

Patients with MWA consolidation therapy had significantly improved PFS (median 16.7 vs. 12.9 months, HR 0.44, 95% CI 0.22-0.88, P = 0.02) and OS (median: 34.8 vs. 22.7 months, HR 0.45, 95% CI 0.24-0.88, P = 0.04) than monotherapy group. MWA for LCT was identified as the independent predictive factor for better PFS (HR 0.46, 95% CI 0.37-0.82, P < 0.01) and OS (HR 0.57, 95% CI 0.33-0.91, P = 0.02). Most toxicities were mild and well tolerated. No patient had to discontinue EGFR-TKIs because of MWA complications. These findings suggest that MWA as local consolidative therapy after first-line EGFR-TKIs treatment leads to better disease control and survival than TKIs monotherapy in EGFR-mutant advanced NSCLC patients with extracranial oligometastasis. MWA as a novel option of LCT might be considered for clinical management of these patients.

Local ablative radiotherapy for oligometastatic non-small cell lung cancer

In metastatic non-small cell lung cancer (NSCLC), the role of radiotherapy (RT) has been limited to palliation to alleviate the symptoms. However, with the development of advanced RT techniques, recent advances in immuno-oncology therapy targeting programmed death 1 (PD-1) and programmed death ligand 1 (PD-L1) and targeted agents for epidermal growth factor receptor (EGFR) mutation or anaplastic lymphoma kinase (ALK) translocation allowed new roles of RT in these patients. Within this metastatic population, there is a subset of patients with a limited number of sites of metastatic disease, termed as oligometastasis that can achieve long-term survival from aggressive local management. There is no consensus on the definition of oligometastasis; however, most clinical trials define oligometastasis as having 3 to 5 metastatic lesions. Recent phase II randomized clinical trials have shown that ablative RT, including stereotactic ablative body radiotherapy (SABR) and hypofractionated RT, to primary and metastatic sites improved progression-free survival (PFS) and overall survival (OS) in patients with oligometastatic NSCLC. The PEMBRO-RT study, a randomized phase II study comparing SABR prior to pembrolizumab therapy and pembrolizumab therapy alone, revealed that the addition of SABR improved the overall response, PFS, and OS in patients with advanced NSCLC. The efficacy of RT in oligometastatic lung cancer has only been studied in phase II studies; therefore, large-scale phase III studies are needed to confirm the benefit of local ablative RT in patients with oligometastatic NSCLC. Local intensified RT to primary and metastatic lesions is expected to become an important treatment paradigm in the near future in patients with metastatic lung cancer.

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.

Improved Overall Survival With Comprehensive Local Consolidative Therapy in Synchronous Oligometastatic Non-Small-Cell Lung Cancer

BACKGROUND

Local consolidative therapy (LCT) to optimize disease control is an evolving management paradigm in non-small-cell lung cancer (NSCLC) patients who present with a limited metastatic disease burden. We hypothesized that LCT to all sites of disease would be associated with improved overall survival (OS) among patients with synchronous oligometastatic NSCLC.

PATIENTS AND METHODS

Patients presenting to a single institution (2000-2017) with stage IV NSCLC and ≤ 3 synchronous metastases were identified. Intrathoracic nodal disease was counted as one site. Landmark and propensity-adjusted Cox regression analyses were performed to identify factors associated with OS.

RESULTS

Of 194 patients, 143 (74%) had 2 or 3 sites of metastasis. LCT was delivered to all sites of disease in 121 patients (62%), to some but not all sites in 52 (27%), and were not used in 21 (11%). Comprehensive LCT was independently associated with improved OS (hazard ratio [HR] = 0.67; 95% confidence interval [CI], 0.46-0.97; P = .034), with the greatest therapeutic effect among patients without thoracic nodal disease, bone metastases, or > 1 metastatic site. Among patients who underwent comprehensive LCT, tumor histology (squamous: HR = 2.32; 95% CI, 1.28-4.22; P = .006), intrathoracic disease burden (T3-4: HR = 1.67; 95% CI, 0.97-2.86; P = .065; N3: HR = 1.90; 95% CI, 0.90-4.03; P = .093), and bone metastases (HR = 1.74; 95% CI, 1.02-3.00; P = .044) were associated with poor OS.

CONCLUSION

Comprehensive LCT was associated with improved OS in this large cohort of patients with synchronous oligometastatic NSCLC. These results support ongoing prospective efforts to characterize the therapeutic benefits associated with this management strategy.

Treatment modes for EGFR mutations in patients with brain metastases from non-small cell lung cancer: controversy, causes, and solutions

Brain metastasis from non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutations is a hot research topic, but also a difficulty in targeted NSCLC therapy, and is also the focus of controversy in the field of lung cancer treatment. According to medical oncology, asymptomatic patients were initially treated with targeted therapy, followed by local radiotherapy when symptoms present or disease progresses. However, from the perspective of the discipline of radiotherapy, brain metastases need to be treated before drug resistance, as it may affect survival. Controversies between disciplines have brought much confusion to the treatment choices of clinicians. We summarized and discussed relevant literatures in this article to seek the truth in providing reference in clinical practice for treating diseases and solving problems.

Synchronous Oligometastatic Non-small Cell Lung Cancer Managed With Curative-Intent Chemoradiation Therapy: Long-term Outcomes From a Single Institution

Purpose

We examined long-term clinical outcomes among patients with synchronous oligometastatic non-small cell lung cancer (NSCLC) treated at our institution with definitive thoracic chemoradiation therapy (CRT) and local therapy to all oligometastatic lesions.

Methods and Materials

A retrospective review identified 38 patients with synchronous oligometastatic NSCLC (≤3 metastatic lesions) who were treated with definitive CRT to the primary tumor and regional lymph nodes between 1999 and 2017 at our institution. Of the 38 patients, 27 patients (71%) received induction chemotherapy, all of whom responded or stabilized with initial systemic therapy before consideration of CRT. Most patients received chemotherapy concurrently with radiation therapy (n = 32; 84%) and local therapy to the metastatic disease site(s) (n = 34; 89%). We assessed patterns of progression or failure, overall survival (OS), progression-free survival (PFS), and toxicities.

Results

The median follow-up duration was 54.9 months. Most patients (84%) presented with N2 to N3 disease. The brain or central nervous system was the most common site of disease progression and occurred in 16 of 28 patients (57%) experiencing any progression and 10 of 16 patients (63%) who initially presented with brain oligometastases. Median OS was 21.1 months (95% confidence interval [CI], 15.6-49.0 months), and median PFS 9.7 months (95% CI, 8.2-14.4 months). The 1-, 2-, and 4-year OS rates were 75.7%, 45.0%, and 33.7%, respectively. On multivariate analysis, both locoregional progression (hazard ratio: 5.8; 95% CI, 2.2-15.0; P = .0003) and distant progression (hazard ratio: 6.0; 95% CI, 2.3-15.4; P = .0002), when treated as time-dependent covariates, were associated with inferior OS. Grade ≥3 esophagitis occurred in 9% and grade ≥3 pneumonitis in 5% of patients with evaluable data.

Conclusions

Patients with synchronous oligometastatic NSCLC and a high regional nodal burden treated with definitive thoracic CRT experienced favorable survival outcomes and low toxicity. At our institution, treating oligometastatic disease with CRT after systemic therapy is incorporated into the treatment plan from the onset of therapy, and we monitor the neuraxis closely for progression during and after treatment. Future research should focus on novel treatment combinations, such as immunotherapy or targeted systemic therapy as appropriate to further improve tumor control and survival.

Combination of Whole-Brain Radiotherapy with Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors Improves Overall Survival in EGFR-Mutated Non-Small Cell Lung Cancer Patients with Brain Metastases

Brain metastases (BM) cause morbidity and mortality in patients with non-small cell lung cancer (NSCLC). The use of upfront epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) and withholding of whole-brain radiation therapy (WBRT) is controversial. We aim to investigate the impact of WBRT on overall survival (OS). After screening 1384 patients, a total of 141 EGFR-mutated patients with NSCLC and BM were enrolled. All patients received EGFR-TKIs between 2011 and 2015. Ninety-four patients (66.7 %) were treated with WBRT (TKI + WBRT group). With a median follow-up of 20.3 months (95% confidence interval (CI), 16.9-23.7), the median OS after the diagnosis of BM was 14.3 months (95% CI, 9.5 to 18.3) in the TKI + WBRT group and 2.3 months (95% CI, 2 to 2.6) in the TKI alone group. On multivariate analysis, WBRT (p < 0.001), female, surgery to primary lung tumor, and surgery to BM were associated with improved OS. The 1-year OS rate was longer in the TKI+WBRT group than that in the TKI alone group (81.9% vs 59.6%, p = 0.002). In conclusion, this is the first study to demonstrate the negative survival impact from the omission of WBRT in patients with EGFR-mutant NSCLC.

Stereotactic body radiotherapy improves the survival of patients with oligometastatic non-small cell lung cancer

Purpose

The aim of the study was to evaluate the efficacy and safety of stereotactic body radiotherapy (SBRT) for pulmonary lesions in oligometastatic non‐small cell lung cancer (NSCLC) patients, to explore prognostic factors of progression‐free survival (PFS) and overall survival (OS), to validate improved survival contributed by SBRT in oligometastatic NSCLC patients.

Patients and methods

A total of 71 oligometastatic NSCLC patients with 86 pulmonary lesions treated with SBRT in our institute between 2012 and 2018 were included. Local control (LC), progression‐free survival (PFS), and overall survival (OS) were calculated using Kaplan‐Meier method. Prognostic factors of PFS and OS were analyzed using univariate and multivariate Cox analyses. Subgroup analyses were performed to investigate the impact of SBRT on PFS and OS during first line systemic treatment.

Results

After a median follow‐up of 17.6 months, 2‐year LC and OS rates were 82.6% and 55.3%, respectively. No grade 4 or more toxicities were observed. Multivariate analysis showed systemic treatment regimen before SBRT was an independent prognostic factor of PFS, but not for OS. Among this cohort, patients receiving first line target therapy could show a better PFS and OS than those undergoing first line chemotherapy (target therapy vs chemotherapy, PFS, 26.4 m vs 6.9 m; OS, 34.8 m vs 15.5 m).

Conclusions

SBRT for pulmonary lesions was a feasible and tolerable option for oligometastatic NSCLC patients. Delivery of SBRT for pulmonary lesions improved outcomes of oligometastatic NSCLC patients. Finally, SBRT combined with first line target therapy might have optimal outcomes.

Local Consolidative Therapy Vs. Maintenance Therapy or Observation for Patients With Oligometastatic Non-Small-Cell Lung Cancer: Long-Term Results of a Multi-Institutional, Phase II, Randomized Study

PURPOSE

Our previously published findings reported that local consolidative therapy (LCT) with radiotherapy or surgery improved progression-free survival (PFS) and delayed new disease in patients with oligometastatic non-small-cell lung cancer (NSCLC) that did not progress after front-line systemic therapy. Herein, we present the longer-term overall survival (OS) results accompanied by additional secondary end points.

PATIENTS AND METHODS

This multicenter, randomized, phase II trial enrolled patients with stage IV NSCLC, three or fewer metastases, and no progression at 3 or more months after front-line systemic therapy. Patients were randomly assigned (1:1) to maintenance therapy or observation (MT/O) or to LCT to all active disease sites. The primary end point was PFS; secondary end points were OS, toxicity, and the appearance of new lesions. All analyses were two sided, and P values less than .10 were deemed significant.

RESULTS

The Data Safety and Monitoring Board recommended early trial closure after 49 patients were randomly assigned because of a significant PFS benefit in the LCT arm. With an updated median follow-up time of 38.8 months (range, 28.3 to 61.4 months), the PFS benefit was durable (median, 14.2 months [95% CI, 7.4 to 23.1 months] with LCT v 4.4 months [95% CI, 2.2 to 8.3 months] with MT/O; P = .022). We also found an OS benefit in the LCT arm (median, 41.2 months [95% CI, 18.9 months to not reached] with LCT v 17.0 months [95% CI, 10.1 to 39.8 months] with MT/O; P = .017). No additional grade 3 or greater toxicities were observed. Survival after progression was longer in the LCT group (37.6 months with LCT v 9.4 months with MT/O; P = .034). Of the 20 patients who experienced progression in the MT/O arm, nine received LCT to all lesions after progression, and the median OS was 17 months (95% CI, 7.8 months to not reached).

CONCLUSION

In patients with oligometastatic NSCLC that did not progress after front-line systemic therapy, LCT prolonged PFS and OS relative to MT/O.

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.

Concurrent EGFR-TKI and Thoracic Radiotherapy as First-Line Treatment for Stage IV Non-Small Cell Lung Cancer Harboring EGFR Active Mutations

LESSONS LEARNED

This single-arm, phase II study shows that concurrent EGFR-tyrosine kinase inhibitor plus thoracic radiotherapy as the first-line treatment for stage IV non-small cell lung cancer harboring EGFR active mutations provides long-term control for the primary lung lesion, and 1-year progression-free survival (PFS) rate and median PFS are numerically higher than those of the erlotinib monotherapy.Serious adverse events are acceptable, although grade >3 radiation pneumonitis occurred in 20% of patients.

BACKGROUND

Studies show effective local control by EGFR-tyrosine kinase inhibitor (TKI) combined with radiotherapy at metastatic sites in advanced lung cancer harboring EGFR active mutations. Salvage local radiotherapy is associated with prolonged progression-free survival (PFS) in local disease during EGFR-TKI treatment. However, no prospective study has been reported on concurrent EGFR-TKI and radiotherapy for primary lung lesions. This study investigated the efficacy and safety of first-line EGFR-TKI combined with thoracic radiotherapy in treating stage IV non-small cell lung cancer (NSCLC) harboring EGFR active mutations.

METHODS

We conducted a single-arm, phase II clinical trial. Each patient received EGFR-TKI (erlotinib 150 mg or gefitinib 250 mg per day) plus thoracic radiotherapy (54-60 Gy/27-30 F/5.5-6 w) within 2 weeks of beginning EGFR-TKI therapy until either disease progression or intolerable adverse events (AEs) appeared.

RESULTS

From January 2015 to March 2018, 401 patients were screened, and 10 patients (5 male and 5 female) were eligible. These patients had a median age of 55 years (40-75) and median follow-up of 19.8 months (5.8-34). The 1-year PFS rate was 57.1%, median PFS was 13 months, and median time to progression of irradiated lesion (iTTP) was 20.5 months. Objective response rate (ORR), was 50% and disease control rate (DCR) was 100%. The most common grade ≥3 AEs were radiation pneumonitis (20%) and rash (10%). One patient died after rejecting treatment for pneumonitis. The others received a full, systematic course of glucocorticoid therapy. Pneumonitis was all well controlled and did not relapse.

CONCLUSION

Concurrent EGFR-TKI plus thoracic radiotherapy as the first-line treatment for stage IV NSCLC harboring EGFR active mutations shows a long-term control of primary lung lesion. The 1-year PFS rate and median PFS of this combined therapy are numerically higher than those of the erlotinib monotherapy. The risk of serious adverse events is acceptable.

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.

Larger tumors are associated with inferior progression-free survival of first-line EGFR-tyrosine kinase inhibitors and a lower abundance of EGFR mutation in patients with advanced non-small cell lung cancer

BACKGROUND

The impact of primary tumor size on the therapeutic outcomes of EGFR-tyrosine kinase inhibitors (TKIs) in advanced non-small cell lung cancer (NSCLC) with EGFR mutation remains unclear.

METHODS

A total of 291 consecutive patients with advanced EGFR-mutant NSCLC administered first-line EGFR-TKIs were enrolled. Computed tomography was used to assess primary tumor diameter. The amplification refractory mutation system plus was used to quantitatively evaluate the abundance of EGFR mutations. Associations between depth of response, abundance of EGFR mutations, and tumor size was investigated.

RESULTS

Patients were divided into three groups according to T classification: ≤ 3 cm (n = 109), 3-5 cm (n = 121), and > 5 cm (n = 61). Median progression-free survival (PFS) was significantly longer in the ≤ 3 cm and 3-5 cm groups compared to the > 5 cm group (10.8 vs. 10.5 vs. 7.1 months; P < 0.001). Subgroup analysis revealed a consistent result in patients with exon 19 deletion and 21 L858R mutation. Multivariate analysis revealed that tumor size was an independent predictive factor for PFS (hazard ratio 1.528, 95% confidence interval 1.104-2.115; P = 0.010). Larger tumors (> 5 cm) were marginally significantly less EGFR-mutant abundant than smaller tumors (≤ 5 cm) (mean ± standard deviation 30.5 ± 29.5% vs. 45.8 ± 43.1%; P = 0.08).

CONCLUSION

Larger tumors (> 5 cm) were associated with inferior PFS of first-line EGFR-TKI therapy in advanced NSCLC patients with activating EGFR mutations. A potential explaination might be that EGFR mutations are less abundant in larger tumors.

Predictive Factors for Response and Survival in a Cohort of Oligometastatic Patients Treated With Stereotactic Body Radiation Therapy

PURPOSE

This study evaluated patients, treatment, or disease characteristics that could predict response to stereotactic body radiation therapy (SBRT) and survival in a database of patients with oligometastatic disease from different solid tumors.

METHODS AND MATERIALS

Patients treated with SBRT for oligometastatic disease between 2014 and 2015 were included. Patients were defined as oligometastatic if they were affected by a maximum of 5 active lesions in 3 different sites. They had to be treated with SBRT with radical intent.

RESULTS

The study included 358 patients. With a median follow-up of 31.83 months, local control at 6 and 24 months was 94.6% and 78.9%, respectively. Distant progression was recorded in 279 patients (77.9%). Progression-free survival at 6 and 24 months was 66.1% and 18.4%, respectively. At last follow-up, 195 patients (54.5%) were still alive in 59 cases with no evidence of disease. The median overall survival (OS) was 34.7 months (95% confidence interval, 29.66-43.83). OS at 6 and 24 months was 96.07% and 63.57%, respectively. On multivariable analysis, the presence of lung metastases (hazard ratio [HR], 0.50 [0.33-0.75]; P = .001) and nodal metastases (HR, 0.44 [0.24-0.78]; P = .005) was related to longer OS. Primary lung cancer (HR, 1.89 [1.14-3.13]; P = .013), increasing age (HR, 1.02 [1.01-1.04]; P = .002), and the presence of metastatic sites other than the irradiated ones (HR, 2.19 [1.39-3.43]; P = .001) were all independent predictors of shorter OS. Local response was associated with OS.

CONCLUSIONS

SBRT for patients with oligometastatic disease is effective. Local response is strongly correlated with patients'' prognosis, also underlying its relevance in a metastatic setting.

Addition of radiotherapy to the primary tumour in oligometastatic NSCLC: A systematic review and meta-analysis

Oligometastatic non-small cell lung cancer (NSCLC) has a discrete number of distant lesions (<5) that can be amenable to radical treatment. The treatment of the primary lung tumour in such stage IV cases is still debated. We conducted a systematic review and meta-analysis to evaluate the outcome of these patients and the added benefit in terms of overall survival (OS) and progression-free survival (PFS) when radical treatment of the primary tumour with radiotherapy (RT) was delivered. PubMed, EMBASE and Cochrane Library were systematically searched to identify relevant studies published up to July 2018. Prospective trials and retrospective series comparing RT vs no RT to the primary NSCLC in the presence of oligometastases were included. Hazard ratios (HRs) for OS and PFS were aggregated according to a fixed or random effect model. Twenty-one studies for a total of 924 synchronous oligometastatic NSCLC were analysed. Median OS and PFS were 20.4 and 12 months. Pooled 1-2-3 and 5-year OS were 70.3%, 43.5%, 29.3% and 20.2% respectively. Overall survival was improved with the addition of thoracic RT (HR = 0.44, 95%CI 0.32-0.6; P < 0.001). Similarly, RT added to the primary tumour increased PFS (HR = 0.42, 95%CI 0.33-0.55; P < 0.001). The only variable associated with the median OS was the year of publication with most recent series associated with a better outcome. In patients with oligometastatic NSCLC and disease controlled with ablative therapy of distant metastases, a consolidation with radical RT to the primary tumour is associated with better survival and could be considered as a treatment modality in selected cases.