Radiotherapy in the management of synchronous metastatic lung cancer

Metastatic lung cancer classically portends a poor prognosis. The management of metastatic lung cancer has dramatically changed with the emergence of immune checkpoint inhibitors, targeted therapy and due to a better understanding of the oligometastatic process. In metastatic lung cancers, radiation therapy which was only used with palliative intent for decades, represents today a promising way to treat primary and oligometastatic sites with a curative intent. Herein we present through a literature review the role of radiotherapy in the management of synchronous metastatic lung cancers.

A prospective study of immune responses in patients with lung metastases treated with stereotactic body radiotherapy with or without concurrent systemic treatment

We prospectively evaluated the effects of stereotactic body radiotherapy (SBRT) on circulating immune cells. Patients with oligo-metastatic and oligo-progressive pulmonary lesions were treated with SBRT with (cSBRT) or without (SBRT group) concurrent systemic treatment (chemotherapy or immune checkpoint blockade) using different fractionation regimes. Immunoprofiling of peripheral blood cells was performed at baseline, during, at the end of SBRT, and at the first and second follow-ups. The study accrued 100 patients (80 with evaluable samples). The proportion of proliferating CD8+ T-cells significantly increased after treatment. This increase remained significant at follow-up in the SBRT group, but not in the cSBRT group and was not detected with doses of >10Gy per fraction indicating that lower doses are necessary to increase proliferating T-cells' frequency. We detected no favorable impact of concurrent systemic treatment on systemic immune responses. The optimal timing of systemic treatment may be post-SBRT to leverage the immune-modulating effects of SBRT.

Systemic immune modulation by stereotactic radiotherapy in early-stage lung cancer

We performed a prospective study of circulating immune cell changes after stereotactic body radiotherapy (SBRT) in 50 early-stage NSCLC patients. We found no significant increase in CD8⁺ cytotoxic T lymphocytes at first follow-up (the primary endpoint) but detected a significant increase in expanding Ki-67⁺CD8⁺ and Ki-67⁺CD4⁺ T-cell fractions in patients treated with 10 Gy or less per fraction. SBRT can induce significant expansion in circulating effector T-cells immediately post-treatment.

Changes in Blood Biomarkers of Angiogenesis and Immune Modulation after Radiation Therapy and Their Association with Outcomes in Thoracic Malignancies

The effects of radiotherapy on systemic immunity remain to be fully characterized in a disease-specific manner. The aim of the study was to examine potential biomarkers of systemic immunomodulation when using radiotherapy for thoracic malignancies. Serial blood samples were collected from 56 patients with thoracic malignancies prior (RTbaseline), during (RTduring) and at the end of radiotherapy (RTend), as well as at the first (FU1) and second follow-up (FU2). The changes in serum levels of IL-10, IFN-γ, IL-12p70, IL-13, IL-1β, IL-4, IL-6, IL-8, TNF-α, bFGF, sFlt-1, PlGF, VEGF, VEGF-C, VEGF-D and HGF were measured by multiplexed array and tested for associations with clinical outcomes. We observed an increase in the levels of IL-10, IFN-γ, PlGF and VEGF-D and a decrease in those of IL-8, VEGF, VEGF-C and sFlt-1 during and at the end of radiotherapy. Furthermore, baseline concentration of TNF-α significantly correlated with OS. IL-6 level at RTend and FU1,2 correlated with OS (RTend: p = 0.039, HR: 1.041, 95% CI: 1.002-1.082, FU1: p = 0.001, HR: 1.139, 95% CI: 1.056-1.228, FU2: p = 0.017, HR: 1.101 95% CI: 1.018-1.192), while IL-8 level correlated with OS at RTduring and RTend (RTduring: p = 0.017, HR: 1.014, 95% CI: 1.002-1.026, RTend: p = 0.004, HR: 1.007, 95% CI: 1.061-1.686). In conclusion, serum levels of TNF-α, IL-6 and IL-8 are potential biomarkers of response to radiotherapy. Given the recent implementation of immunotherapy in lung and esophageal cancer, these putative blood biomarkers should be further validated and evaluated in the combination or sequential therapy setting.

Low-Dose Radiation Potentiates the Propagation of Anti-Tumor Immunity against Melanoma Tumor in the Brain after In Situ Vaccination at a Tumor outside the Brain

Brain metastases develop in over 60% of advanced melanoma patients and negatively impact quality of life and prognosis. In a murine melanoma model, we previously showed that an in situ vaccination (ISV) regimen, combining radiation treatment and intratumoral (IT) injection of immunocytokine (IC: anti-GD2 antibody fused to IL2), along with the immune checkpoint inhibitor anti-CTLA-4, robustly eliminates peripheral flank tumors but only has modest effects on co-occurring intracranial tumors. In this study, we investigated the ability of low-dose radiation to the brain to potentiate anti-tumor immunity against a brain tumor when combined with ISV + anti-CTLA-4. B78 (GD2+, immunologically "cold") melanoma tumor cells were implanted into the flank and the right striatum of the brain in C57BL/6 mice. Flank tumors (50-150 mm3) were treated following a previously optimized ISV regimen [radiation (12 Gy × 1, treatment day 1), IT-IC (50 µg daily, treatment days 6-10), and anti-CTLA-4 (100 µg, treatment days 3, 6, 9)]. Mice that additionally received whole-brain radiation treatment (WBRT, 4 Gy × 1) on day 15 demonstrated significantly increased survival compared to animals that received ISV + anti-CTLA-4 alone, WBRT alone or no treatment (control) (P < 0.001, log-rank test). Timing of WBRT was critical, as WBRT administration on day 1 did not significantly enhance survival compared to ISV + anti-CTLA-4, suggesting that the effect of WBRT on survival might be mediated through immune modulation and not just direct tumor cell cytotoxicity. Modest increases in T cells (CD8+ and CD4+) and monocytes/macrophages (F4/80+) but no changes in FOXP3+ regulatory T cells (Tregs), were observed in brain melanoma tumors with addition of WBRT (on day 15) to ISV + anti-CTLA-4. Cytokine multiplex immunoassay revealed distinct changes in both intracranial melanoma and contralateral normal brain with addition of WBRT (day 15) to ISV + anti-CTLA-4, with notable significant changes in pro-inflammatory (e.g., IFNγ, TNFα and LIX/CXCL5) and suppressive (e.g., IL10, IL13) cytokines as well as chemokines (e.g., IP-10/CXCL10 and MIG/CXCL9). We tested the ability of the alkylphosphocholine analog, NM600, to deliver immunomodulatory radiation to melanoma brain tumors as a targeted radionuclide therapy (TRT). Yttrium-86 (86Y) chelated to NM600 was delivered intravenously by tail vein to mice harboring flank and brain melanoma tumors, and PET imaging demonstrated specific accumulation up to 72 h at each tumor site (∼12:1 brain tumor/brain and ∼8:1 flank tumor/muscle). When NM600 was chelated to therapeutic β-particle-emitting 90Y and administered on treatment day 13, T-cell infiltration and cytokine profiles were altered in melanoma brain tumor, like that observed for WBRT. Overall, our results demonstrate that addition of low-dose radiation, timed appropriately with ISV administration to tumors outside the brain, significantly increases survival in animals co-harboring melanoma brain tumors. This observation has potentially important translational implications as a treatment strategy for increasing the response of tumors in the brain to systemically administered immunotherapies.

Radiation therapy and immunotherapy in breast cancer treatment: preliminary data and perspectives

Introduction: The discovery of the major role of the immune system in the tumor process has led to the development of therapeutic strategies with immunotherapy. The potential systemic role of radiotherapy, (RT) used for a long time for its local action, based on its impact on immunity, is now better understood. The combination of immunotherapy and radiation therapy is currently a field of sustained research programs and has shown successful results, in non-small cell lung cancer, for example. Breast cancer (BC) was wrongly considered poorly immunogenic and put aside during accelerating progress in this new area of treatment.Areas covered: This review provides an overview of pre-clinical and clinical rationales to associate immunotherapy with radiation therapy in the management of breast cancer.Expert opinion: Immunotherapy has been used only recently in breast cancer, but clinical trials have yet to determine the place of this treatment. RT may be useful to enhance the response of breast tumors to immunotherapy. This new approach in breast cancer management is currently based on limited data but should be further investigated, especially in triple-negative breast cancer and in the neoadjuvant setting.

The changing landscape of stage III lung cancer: a literature review

INTRODUCTION

The treatment of stage III non-small cell lung cancer (NSCLC) remains challenging and associated with overall poor outcomes. Since seminal studies in the early 90s introduced concurrent chemo-radiotherapy as standard of care for treatment of this disease, no major advances have been introduced in this landscape. Both radiation dose escalation and neoadjuvant/adjuvant chemotherapy strategies were unsuccessful to improve the survival over standard of care radiation dose and chemotherapy schedule: five-year overall survival (OS) ranging from 15-20%. However, in 2017 the PACIFIC Trial demonstrated that the addition of consolidative immune checkpoint inhibitor durvalumab for 1 year led to superior progression-free survival (PFS) and 3-year overall survival with no significant increase in toxicity compared to placebo in patients who achieved disease control with concurrent chemo-RT.

AREAS COVERED

This article reviews the treatment evolution of stage III NSCLC over the past decades, discusses current standard of care strategies, and highlights potential future directions for the management of this condition.

EXPERT OPINION

Ongoing trials incorporating upfront checkpoint inhibitors with radiotherapy will answer whether adding checkpoint inhibitors to chemotherapy or substituting them for chemotherapy altogether will improve long-term outcome.

In situ vaccination at a peripheral tumor site augments response against melanoma brain metastases

BACKGROUND

Immune checkpoint inhibition (ICI) alone is not efficacious for a large number of patients with melanoma brain metastases. We previously established an in situ vaccination (ISV) regimen combining radiation and immunocytokine to enhance response to ICIs. Here, we tested whether ISV inhibits the development of brain metastases in a murine melanoma model.

METHODS

B78 (GD2+) melanoma 'primary' tumors were engrafted on the right flank of C57BL/6 mice. After 3-4 weeks, primary tumors were treated with ISV (radiation (12 Gy, day 1), α-GD2 immunocytokine (hu14.18-IL2, days 6-10)) and ICI (α-CTLA-4, days 3, 6, 9). Complete response (CR) was defined as no residual tumor observed at treatment day 90. Mice with CR were tested for immune memory by re-engraftment with B78 in the left flank and then the brain. To test ISV efficacy against metastases, tumors were also engrafted in the left flank and brain of previously untreated mice. Tumors were analyzed by quantitative reverse transcription-PCR, immunohistochemistry, flow cytometry and multiplex cytokine assay.

RESULTS

ISV+α-CTLA-4 resulted in immune memory and rejection of B78 engraftment in the brain in 11 of 12 mice. When B78 was engrafted in brain prior to treatment, ISV+α-CTLA-4 increased survival compared with ICI alone. ISV+α-CTLA-4 eradicated left flank tumors but did not elicit CR at brain sites when tumor cells were engrafted in brain prior to ISV. ISV+α-CTLA-4 increased CD8+ and CD4+ T cells in flank and brain tumors compared with untreated mice. Among ISV + α-CTLA-4 treated mice, left flank tumors showed increased CD8+ infiltration and CD8+:FOXP3+ ratio compared with brain tumors. Flank and brain tumors showed minimal differences in expression of immune checkpoint receptors/ligands or Mhc-1. Cytokine productions were similar in left flank and brain tumors in untreated mice. Following ISV+α-CTLA-4, production of immune-stimulatory cytokines was greater in left flank compared with brain tumor grafts.

CONCLUSION

ISV augmented response to ICIs in murine melanoma at brain and extracranial tumor sites. Although baseline tumor-immune microenvironments were similar at brain and extracranial tumor sites, response to ISV+α-CTLA-4 was divergent with reduced infiltration and activation of immune cells in brain tumors. Additional therapies may be needed for effective antitumor immune response against melanoma brain metastases.

Abscopal effect in lung cancer: three case reports and a concise review

The abscopal effect describes the ability of locally administered radiotherapy to induce systemic antitumor effects. Over the past 40 years, reports on the abscopal effect following conventional radiation have been relatively rare, especially in less immunogenic tumors such as lung cancer. However, with the continued development and use of immunotherapy, reports on the abscopal effect have become increasingly frequent during the last decade. Here, we present three illustrative case reports from our own institution and previous published cases of the abscopal effect in patients with non-small cell lung cancer, treated with immune checkpoint inhibitors and radiotherapy. We also present a concise review of the clinical and experimental literature on the abscopal effect in non-small cell lung cancer.

A phase 2 clinical trial assessing the efficacy and safety of pembrolizumab and radiotherapy in patients with metastatic triple-negative breast cancer

BACKGROUND

The current study was conducted to evaluate the efficacy and safety of pembrolizumab-mediated programmed cell death protein 1 inhibition plus radiotherapy (RT) in patients with metastatic triple-negative breast cancer who were unselected for programmed death-ligand 1 expression.

METHODS

The current study was a single-arm, Simon 2-stage, phase 2 clinical trial that enrolled a total of 17 patients with a median age of 52 years (range, 37-73 years). An RT dose of 3000 centigrays (cGy) was delivered in 5 daily fractions. Pembrolizumab was administered intravenously at a dose of 200 mg within 3 days of the first RT fraction, and then every 3 weeks ± 3 days until disease progression. The median follow-up was 34.5 weeks (range, 2.1-108.3 weeks). The primary endpoint of the current study was the overall response rate (ORR) at week 13 in patients with unirradiated lesions measured using Response Evaluation Criteria in Solid Tumors (RECIST; version 1.1). Secondary endpoints included safety and progression-free survival. Exploratory objectives were to identify biomarkers predictive of ORR and progression-free survival.

RESULTS

The ORR for the entire cohort was 17.6% (3 of 17 patients; 95% CI, 4.7%-44.2%), with 3 complete responses (CRs), 1 case of stable disease, and 13 cases of progressive disease. Eight patients died prior to week 13 due to disease progression. Among the 9 women assessed using RECIST version 1.1 at week 13, 3 (33%) achieved a CR, with a 100% reduction in tumor volume outside of the irradiated portal. The CRs were durable for 18 weeks, 20 weeks, and 108 weeks, respectively. The most common grade 1 to 2 toxicity (assessed according to the National Cancer Institute Common Terminology Criteria for Adverse Events, version 4.0) was dermatitis (29%). Four grade 3 adverse events were attributed to pembrolizumab: fatigue, lymphopenia, and infection. No were no grade 4 adverse events or treatment-related deaths reported.

CONCLUSIONS

The combination of pembrolizumab and RT was found to be safe and demonstrated encouraging activity in patients with poor-prognosis, metastatic, triple-negative breast cancer who were unselected for programmed death-ligand 1 expression. Larger clinical trials of checkpoint blockade plus RT with predictive biomarkers of response are needed.

Development of an In Situ Cancer Vaccine via Combinational Radiation and Bacterial-Membrane-Coated Nanoparticles

Neoantigens induced by random mutations and specific to an individual's cancer are the most important tumor antigens recognized by T cells. Among immunologically "cold" tumors, limited recognition of tumor neoantigens results in the absence of a de novo antitumor immune response. These "cold" tumors present a clinical challenge as they are poorly responsive to most immunotherapies, including immune checkpoint inhibitors (ICIs). Radiation therapy (RT) can enhance immune recognition of "cold" tumors, resulting in a more diversified antitumor T-cell response, yet RT alone rarely results in a systemic antitumor immune response. Therefore, a multifunctional bacterial membrane-coated nanoparticle (BNP) composed of an immune activating PC7A/CpG polyplex core coated with bacterial membrane and imide groups to enhance antigen retrieval is developed. This BNP can capture cancer neoantigens following RT, enhance their uptake in dendritic cells (DCs), and facilitate their cross presentation to stimulate an antitumor T-cell response. In mice bearing syngeneic melanoma or neuroblastoma, treatment with BNP+RT results in activation of DCs and effector T cells, marked tumor regression, and tumor-specific antitumor immune memory. This BNP facilitates in situ immune recognition of a radiated tumor, enabling a novel personalized approach to cancer immunotherapy using off-the-shelf therapeutics.

When Should we Irradiate the Primary in Metastatic Lung Cancer?

Metastatic lung cancer encompasses a heterogenous group of patients in terms of burdens of disease, ranging from patients with extensive metastases to those with a limited number of metastatic lesions (oligometastatic disease). Histopathological heterogeneity also exists within two broad categories, non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC), portraying different patterns and evolution of disease. Local consolidative therapy to the primary tumour and metastatic sites, including surgery and/or radical dose radiotherapy, is increasingly being used to improve survival outcomes, particularly in the context of oligometastatic disease, with or without the use of molecular targeted therapy and immunotherapy. Recently, randomised studies in oligometastatic NSCLC have shown that local consolidative therapy may confer a survival advantage. This review explores whether treating just the primary tumour with radiotherapy may similarly produce improved clinical outcomes. Such a treatment strategy may carry less potential toxicity than treating multiple sites upfront. The biological rationale behind the potential benefits of treating just the primary in metastatic malignancy is discussed. The clinical evidence of such an approach across tumour sites, such as breast and prostate cancer, is also explored. Then the review focuses on treating the primary in NSCLC and SCLC with radiotherapy, by first exploring patterns of failure in metastatic NSCLC and second exploring evidence on survival outcomes from studies in metastatic NSCLC and SCLC. It is challenging to draw conclusions on the clinical benefit of treating the primary cancer in isolation from the evidence available. This highlights the need to collect data within the ongoing clinical trials on the clinical outcome and toxicity of radiotherapy delivery to primary thoracic disease specifically. This challenge also identifies the need to design future clinical trials to produce randomised evidence for such an approach.

Perspectives in melanoma: meeting report from the Melanoma Bridge (November 29th-1 December 1st, 2018, Naples, Italy)

Diagnosis of melanocytic lesions, correct prognostication of patients, selection of appropriate adjuvant and systemic therapies, and prediction of response to a given therapy remain very real challenges in melanoma. Recent studies have shown that immune checkpoint blockade that represents a forefront in cancer therapy, provide responses but they are not universal. Improved understanding of the tumor microenvironment, tumor immunity and response to therapy has prompted extensive translational and clinical research in melanoma. Development of novel biomarker platforms may help to improve diagnostics and predictive accuracy for selection of patients for specific treatment. There is a growing evidence that genomic and immune features of pre-treatment tumor biopsies may correlate with response in patients with melanoma and other cancers they have yet to be fully characterized and implemented clinically. For example, advancements in sequencing and the understanding of the tumor microenvironment in melanoma have led to the use of genome sequencing and gene expression for development of multi-marker assays that show association with inflammatory state of the tumor and potential to predict response to immunotherapy. As such, melanoma serves as a model system for understanding cancer immunity and patient response to immunotherapy, either alone or in combination with other treatment modalities. Overall, the aim for the translational and clinical studies is to achieve incremental improvements through the development and identification of optimal treatment regimens, which increasingly involve doublet as well as triplet combinations, as well as through development of biomarkers to improve immune response. These and other topics in the management of melanoma were the focus of discussions at the fourth Melanoma Bridge meeting (November 29th–December 1st, 2018, Naples, Italy), which is summarised in this report.

A Review of Ongoing Trials of Stereotactic Ablative Radiotherapy for Oligometastatic Cancers: Where Will the Evidence Lead?

Purpose: The oligometastatic state is a proposed entity between localized cancer and widely metastatic disease, comprising an intermediate subset of metastatic cancer patients. Most data to support locally-directed treatment, such as stereotactic ablative radiotherapy (SABR), for oligometastases are from retrospective institutional reports. Following the success of a recently completed and reported phase II trial demonstrating important clinical outcomes, herein we review the current landscape of ongoing clinical trials in this context. Materials and methods: A review of currently activated and registered clinical trials was performed using the clinicaltrials.gov database from inception to February 2019. A search of actively recruiting trials, using the key words oligometastases, SABR, and various related terms was performed. Search results were independently reviewed by two investigators, with discrepancies settled by a third. Data abstracted from identified studies included study type, primary disease site, oncologic endpoints, and inclusion/exclusion criteria. Results: Of the initial 216 entries identified, 64 met our review eligibility criteria after full-text review. The most common study type was a phase II clinical trial (n = 35, 55%) with other study designs ranging from observational registry trials to phase III randomized controlled trials (RCTs). A minority of trials were randomized in design (n = 17, 27%). While most studies allowed for metastases from multiple primary disease sites (n = 22, 34%), the most common was prostate (n = 13, 15%), followed by breast, gastrointestinal, non-small cell lung cancer (NSCLC), and renal (n = 6, 9% each). In studies with a solitary target site, the most common was liver (n = 6, 9%) followed by lung (n = 3, 5%). The most common primary endpoints were progression-free survival (PFS) (n = 20, 31%) and toxicity (n = 10, 16%). A combined strategy of systemic therapy and SABR was an emerging theme (n = 23, 36%), with more recent studies specifically evaluating SABR and immunotherapy (n = 9, 14%). Conclusion: The safety and efficacy of SABR as oligometastasis-directed treatment is increasingly being evaluated within prospective clinical trials. These data are awaited to compliment the abundance of existing observational studies and to guide clinical decision-making.

Stereotactic Ablative Radiotherapy Combined with Immune Checkpoint Inhibitors Reboots the Immune Response Assisted by Immunotherapy in Metastatic Lung Cancer: A Systematic Review

Background: Immune checkpoint inhibitors (ICI) have represented a revolution in the treatment of non-small-cell lung cancer (NSCLC). To improve these results, combined approaches are being tested. The addition of stereotactic ablative radiotherapy (SABR) to ICI seems promising. A systematic review was performed in order to assess the safety and efficacy of SABR-ICI combination. Material and Methods: MEDLINE databases from 2009 to March 3, 2019 were reviewed to obtain English language studies reporting clinical outcomes of the combination of ICI-SABR in NSCLC. 18 out of the 429 initial results fulfilled the inclusion criteria and were selected for review. Results: Eighteen articles, including six prospective studies, describing 1736 patients treated with an ICI-SABR combination fulfilled the selection criteria. The reported mean rates for local control and distant/abscopal response rates were 71% and 41%, respectively. Eleven studies reported progression-free survival and overall survival, with a mean of 4.6 and 12.4 months, respectively. Toxicity rates were consistent with the ones attributable to ICI treatment alone. Conclusions: The ICI-SABR combination has a good safety profile and achieves high rates of local control and greater chances of obtaining abscopal responses than SABR alone, with a relevant impact on PFS. More studies are needed to improve patient selection for an optimal benefit from this approach.

The Abscopal Effect of Stereotactic Radiotherapy and Immunotherapy: Fool's Gold or El Dorado?

An 'abscopal' effect if often used to refer to distant tumour regression after localised irradiation. Since the first report of the abscopal effect in the 1950s, well-documented cases with radiotherapy alone are very rare. It is widely accepted that the immune response plays an important role in the abscopal effect, although the mechanism is still unclear. With the recent success of cancer immunotherapy, there is growing interest in combining immunotherapy with radiotherapy to boost abscopal response rates. Compared with conventional radiotherapy, stereotactic ablative radiotherapy (SABR) not only delivers ablative dose to the tumour, but may also induce robust immune responses. In this review we examine studies that combine SABR and immunotherapy. We review the preclinical rationale for SABR and immunotherapy combinations, the case for and against abscopal effects, and the current landscape of clinical trials.

Long term efficacy and toxicity after stereotactic ablative reirradiation in locally relapsed stage III non-small cell lung cancer

BACKGROUND

In stage III non-small cell lung cancer (NSCLC) treated with concomitant chemoradiotherapy, there is a high rate of relapse. Some of these relapses are only local and can be treated by stereotactic ablative radiation therapy (SABR). Previous studies reporting outcome after SABR reirradiation of the thorax consisted of a heterogeneous population of various lung cancer stages or even different types of cancer. The purpose of study is to evaluate toxicity and outcome of this strategy in locally relapsed stage III NSCLC only.

METHODS

From February 2007 to November 2015, 46 Stage III NSCLC patients treated with SABR, for lung recurrence following conventionally fractionated radiation therapy (CFRT), were retrospectively analyzed.

RESULTS

Median follow-up was 47.3 months (1-76.9). The 2 and 4-year progression-free survival (PFS), and overall survival (OS) were of 25.5%/8.6 and 48.9%/30.8%, respectively. Highest presenting toxicity in patients (grade 1 through 5) was: 13 (28.3%), 7 (15.2%), 1 (2.2%), 0 and 2 (4.4%), with deaths due to hemoptysis (n = 1) and alveolitis (n = 1). Although the Biological Effective Dose (at Planning Tumor Volume isocenter) was lower for central tumors treated for an in-field relapse (n = 21, 116 Gy versus 168 Gy, p = 0.005), they had no significant difference in OS than the remaining cohort, but with a higher rate of grade 2-5 toxicities (OR = 0.22, [0.06-0.8], p = 0.02).

CONCLUSION

Reirradiation with SABR for local relapse in patients previously treated for stage III NSCLC, is feasible and associated with good outcome. This is also true for central tumors treated for an in-field relapse, but should be radiated with caution to mitigate toxicity.

Real-world evidenceand clinical observations of the treatment of advanced non-small cell lung cancer with PD-1/PD-L1 inhibitors

To summarize the therapeutic effects of PD-1/PD-L1 inhibitors on patients with advanced non-small cell lung cancer (NSCLC) in a real-world setting, we attempted to identify potential molecular biomarkers or clinical factors that reflected the therapeutic effect. The medical records of patients with non-small cell lung cancer who were treated with PD-1/PD-L1 inhibitors were obtained from the outpatient department or inpatient department of Peking Union Medical College Hospital from August 1, 2015, to January 1, 2018. Our follow-up continued until May 1,2018. We chose overall survival (OS) as the primary observation endpoint and progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR), and safety as the secondary observation endpoints. Efficacy was evaluated according to the Response Evaluation Criteria in Solid Tumors (RECIST) 1.1. The Kaplan-Meier method was used to generate survival curves, and we compared the influence of different factors on PFS and OS by the log-rank test. The median follow-up time was 11 months. At the end of the follow-up, 24 patients (61.5%) were still undergoing immunotherapy, and 7 patients (17.9%) had died. Twenty-six cases (66.7%) employed PD-1/PD-L1 inhibitors as first-line treatment, and 7 cases (17.9%) employed PD-1/PD-L1 inhibitors as second-line treatment. Only 6 cases (15.4%) employed PD-1/PD-L1 inhibitors as third-line treatment. Therapeutic effect evaluation: Complete response (CR): 1 case (2.6%). Partial response (PR): 10 cases (25.6%). Stable disease (SD): 16 cases (41.0%). Progressive disease (PD): 12 cases (30.8%). The ORR was 28.2%, and DCR was 69.2%. The median PFS was 25.5 months (95% CI 6.8–44.1 months), which failed to reach the median OS. PD-1/PD-L1 inhibitor treatment is more effective for advanced non-small cell lung cancer patients in a real-world setting than in clinical trials; PD-1/PD-L1 inhibitor treatment is more effective for people who are over 70 than for people who are under 70. Additionally, patients who are over 75 years old have a higher response rate, suggesting that elderly patients may receive more benefits from immunotherapy; Patients who have an epidermal growth factor receptor (EGFR) mutation (+) may benefit from immunotherapy after treatment with a tyrosine kinase inhibitor (TKI). It is essential to identify these potential patients from the entire patient pool; PD-1 may have a certain curative effect on brain metastases from NSCLC. Local radiotherapy may help to improve PD-1 intracranial efficacy.

Nivolumab and stereotactic radiation therapy for the treatment of patients with Stage IV non-small-cell lung cancer

Background

Radiation therapy might modify the cancer immune environment to enhance the antitumor effect of immune checkpoint inhibitors. We performed a feasibility study of nivolumab following stereotactic radiation therapy for chemotherapy pretreated advanced non-small-cell lung cancer.

Patients and methods

Pretreated advanced/recurrent non-small-cell lung cancer patients received stereotactic radiation therapy to one of the disease sites. Nivolumab at a dose of 3 mg/kg was given within 2 weeks after the completion of stereotactic radiation therapy and continued every 2 weeks thereafter until disease progression or unacceptable toxicities. The primary endpoint was the occurrence rate of Grade 3 pneumonitis (within 12 weeks) or other non-hematological toxicity (within 8 weeks).

Results

From September 2016 to September 2017, six patients were enrolled. Five received stereotactic radiation therapy to their primary lesions. All patients received nivolumab on the following day after stereotactic radiation therapy completion. Grade 3 pneumonitis occurred in one patient, but no other serious adverse events were reported for the other patients. One complete response and two partial responses were achieved. Four patients had measurable lesions outside the irradiated area, of whom three patients responded to the treatment. The initial progression sites were mainly outside the irradiated field, including one brain metastasis.

Conclusions

Nivolumab therapy immediately following stereotactic radiation therapy was well tolerated. This sequential combination warrants further study.

Phase Ib evaluation of a self-adjuvanted protamine formulated mRNA-based active cancer immunotherapy, BI1361849 (CV9202), combined with local radiation treatment in patients with stage IV non-small cell lung cancer

BACKGROUND

Preclinical studies demonstrate synergism between cancer immunotherapy and local radiation, enhancing anti-tumor effects and promoting immune responses. BI1361849 (CV9202) is an active cancer immunotherapeutic comprising protamine-formulated, sequence-optimized mRNA encoding six non-small cell lung cancer (NSCLC)-associated antigens (NY-ESO-1, MAGE-C1, MAGE-C2, survivin, 5T4, and MUC-1), intended to induce targeted immune responses.

METHODS

We describe a phase Ib clinical trial evaluating treatment with BI1361849 combined with local radiation in 26 stage IV NSCLC patients with partial response (PR)/stable disease (SD) after standard first-line therapy. Patients were stratified into three strata (1: non-squamous NSCLC, no epidermal growth factor receptor (EGFR) mutation, PR/SD after ≥4 cycles of platinum- and pemetrexed-based treatment [n = 16]; 2: squamous NSCLC, PR/SD after ≥4 cycles of platinum-based and non-platinum compound treatment [n = 8]; 3: non-squamous NSCLC, EGFR mutation, PR/SD after ≥3 and ≤ 6 months EGFR-tyrosine kinase inhibitor (TKI) treatment [n = 2]). Patients received intradermal BI1361849, local radiation (4 × 5 Gy), then BI1361849 until disease progression. Strata 1 and 3 also had maintenance pemetrexed or continued EGFR-TKI therapy, respectively. The primary endpoint was evaluation of safety; secondary objectives included assessment of clinical efficacy (every 6 weeks during treatment) and of immune response (on Days 1 [baseline], 19 and 61).

RESULTS

Study treatment was well tolerated; injection site reactions and flu-like symptoms were the most common BI1361849-related adverse events. Three patients had grade 3 BI1361849-related adverse events (fatigue, pyrexia); there was one grade 3 radiation-related event (dysphagia). In comparison to baseline, immunomonitoring revealed increased BI1361849 antigen-specific immune responses in the majority of patients (84%), whereby antigen-specific antibody levels were increased in 80% and functional T cells in 40% of patients, and involvement of multiple antigen specificities was evident in 52% of patients. One patient had a partial response in combination with pemetrexed maintenance, and 46.2% achieved stable disease as best overall response. Best overall response was SD in 57.7% for target lesions.

CONCLUSION

The results support further investigation of mRNA-based immunotherapy in NSCLC including combinations with immune checkpoint inhibitors.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01915524 .

Overall survival according to immunotherapy and radiation treatment for metastatic non-small-cell lung cancer: a National Cancer Database analysis

Background

Preclinical studies suggest enhanced anti-tumor activity with combined radioimmunotherapy. We hypothesized that radiation (RT) + immunotherapy would associate with improved overall survival (OS) compared to immunotherapy or chemotherapy alone for patients with newly diagnosed metastatic non-small-cell lung cancer (NSCLC).

Methods

The National Cancer Database was queried for patients with stage IV NSCLC receiving chemotherapy or immunotherapy from 2013 to 2014. RT modality was classified as stereotactic radiotherapy (SRT) to intra- and/or extracranial sites or non-SRT external beam RT (EBRT). OS was analyzed using the Kaplan-Meier method and Cox proportional hazards models.

Results

In total, 44,498 patients were included (13% immunotherapy, 46.8% EBRT, and 4.7% SRT). On multivariate analysis, immunotherapy (hazard ratio [HR]:0.81, 95% confidence interval [CI]:0.78–0.83) and SRT (HR:0.78, 95%CI:0.70–0.78) independently associated with improved OS; however, the interaction term for SRT + immunotherapy was insignificant (p = 0.89). For immunotherapy patients, the median OS for no RT, EBRT, and SRT was 14.5, 10.9, and 18.2 months, respectively (p < 0.0001), and EBRT (HR:1.37, 95%CI:1.29–1.46) and SRT (HR:0.78, 95%CI:0.66–0.93) associated with OS on multivariate analysis. In the SRT subset, median OS for immunotherapy and chemotherapy was 18.2 and 14.3 months, respectively (p = 0.004), with immunotherapy (HR:0.82, 95%CI:0.69–0.98) associating with OS on multivariate analysis. Furthermore, for patients receiving SRT, biologically effective dose (BED) > 60 Gy was independently associated with improved OS (HR:0.79, 95%CI:0.70–0.90, p < 0.0001) on multivariate analysis with a significant interaction between BED and systemic treatment (p = 0.008).

Conclusions

Treatment with SRT associated with improved OS for patients with metastatic NSCLC irrespective of systemic treatment. The high survival for patients receiving SRT + immunotherapy strongly argues for evaluation in randomized trials.

Radiation Therapy and Immune Modulation

Radiotherapy has known immunomodulatory effects and there exists a strong preclinical rationale for combining radiotherapy with immunotherapies. Broadly, the concurrent administration of immunotherapies and radiotherapy does not seem to result in undue toxicity, even when radiotherapy is administered to definitive doses. Recently reported results from prospective clinical trials evaluating radiotherapy/ICB combinations, such as the PACIFIC trial, provide important information on safety and efficacy in the definitive setting and identify potential abscopal effects. This review details the preclinical foundation for the combination of radiotherapy and immunotherapies, summarizes the most recent clinical data available, and highlights active and future areas of study.

Combining Radiotherapy With Anti-angiogenic Therapy and Immunotherapy; A Therapeutic Triad for Cancer?

Radiotherapy has been used for the treatment of cancer for over a century. Throughout this period, the therapeutic benefit of radiotherapy has continuously progressed due to technical developments and increased insight in the biological mechanisms underlying the cellular responses to irradiation. In order to further improve radiotherapy efficacy, there is a mounting interest in combining radiotherapy with other forms of therapy such as anti-angiogenic therapy or immunotherapy. These strategies provide different opportunities and challenges, especially with regard to dose scheduling and timing. Addressing these issues requires insight in the interaction between the different treatment modalities. In the current review, we describe the basic principles of the effects of radiotherapy on tumor vascularization and tumor immunity and vice versa. We discuss the main strategies to combine these treatment modalities and the hurdles that have to be overcome in order to maximize therapeutic effectivity. Finally, we evaluate the outstanding questions and present future prospects of a therapeutic triad for cancer.

Organ-specific response to nivolumab in patients with non-small cell lung cancer (NSCLC)

BACKGROUND

Response to immune checkpoint inhibitors depends on tumor intrinsic properties and also on host factors in the tumour microenvironment including the presence of immune cells (IC). We hypothesized that nivolumab efficacy varies across different metastatic sites.

METHODS

We retrospectively analyzed computed tomography scans of patients with metastatic non-small cell lung carcinoma (NSCLC) receiving nivolumab. RECIST 1.1 criteria were applied to assess the overall response rate (ORR) and organ-specific response rate (OSRR).

RESULTS

We analyzed 52 patients including 44% females, 58% adenocarcinoma and 8% never smokers. Involved organs had target-lesions in the lung (42%), liver (25%), lymph nodes (56%) and soft tissue (13%) and non-target lesions in the bones (23%). ORR and disease control rate (DCR) were 20% and 45%, respectively. Median overall survival, progression-free survival and duration of response were 11.9, 2.3 and 10.3 months. OSRR and organ-specific DCR (OSDCR) were 28% and 90% in lymph nodes, 8% and 54 in the liver, and 9% and 55% in lung metastases. Nine out of 12 patients with bone metastases had progressive lesions. The cumulative incidence probability of organ-specific progression at 6 months was 14% in lymph nodes, 42% in the liver, 36% in lung metastases and 26% in the primary tumor, 29% in soft tissue and 33% in adrenal metastases.

CONCLUSION

In conclusion, the efficacy of immunotherapy is dependent on the metastatic location. Treatment appears more active in lymph nodes compared to other organ sites such as liver, adrenals and bone. Future strategies may include additional local treatment in case of oligoprogression in these organs in patients with otherwise sustained treatment benefit.

Checkpoint Inhibition: Will Combination with Radiotherapy and Nanoparticle-Mediated Delivery Improve Efficacy?

Checkpoint inhibition (CPI) has been a rare success story in the field of cancer immunotherapy. Knowledge gleaned from preclinical studies and patients that do not respond to these therapies suggest that the presence of tumor-infiltrating lymphocytes and establishment of immunostimulatory conditions, prior to CPI treatment, are required for efficacy of CPI. To this end, radiation therapy (RT) has been shown to promote immunogenic cell-death-mediated tumor-antigen release, increase infiltration and cross-priming of T cells, and decreasing immunosuppressive milieu in the tumor microenvironment, hence allowing CPI to take effect. Preclinical and clinical studies evaluating the combination of RT with CPI have been shown to overcome the resistance to either therapy alone. Additionally, nanoparticle and liposome-mediated delivery of checkpoint inhibitors has been shown to overcome toxicities and improve therapeutic efficacy, providing a rationale for clinical investigations of nanoparticle, microparticle, and liposomal delivery of checkpoint inhibitors. In this review, we summarize the preclinical and clinical studies of combined RT and CPI therapies in various cancers, and review findings from studies that evaluated nanoparticle and liposomal delivery of checkpoint inhibitors for cancer treatments.

ASCO 2018 NSCLC highlights-combination therapy is key

Non-small cell lung cancer (NSCLC) treatment was booming at this year's ASCO 2018 meeting as several well-performed phase III trials with practice-changing potential were presented. Thereby immune checkpoint blockade (ICB) consolidated its major role in the treatment of NSCLC patients without genetic alterations and extended its use by showing impressive data on ICB combination therapies (mainly combined with chemotherapy). Furthermore the role of predictive biomarkers for ICB therapy (Programmed death-ligand 1 [PD-L1] expression, tumor mutational burden [TMB] testing and others) have been further developed and blood-based tests were presented with promising data revealing the potential of this minimally invasive method for treatment monitoring and guidance in the future. Nevertheless the best biomarker is still elusive and future research is ongoing and might be a multimodal approach combining different modalities. No major studies concerning new genetic alterations or innovative targets were presented and the focus in genetic driven NSCLC was the evaluation of combinational approaches (e.g. in epidermal growth factor receptor [EGFR] mutation positve patients, EGFR tyrosine kinase inhibitor [TKI] plus anti-angiogenic agent or chemotherapy backbone). The presented results showed some benefit for the combinational approach; however toxicity might be an issue and further validation is necessary. Summarizing, ASCO 2018 showed that combinational approaches will be the future standard treatment in NSCLC and that biomarker identification is more heterogeneous and complex than anticipated, but presented next generation techniques may pave the way to a more personalized cancer therapy.