A Randomized Open-Label Phase III Trial Evaluating the Addition of Denosumab to Standard First-Line Treatment in Advanced NSCLC: The European Thoracic Oncology Platform (ETOP) and European Organisation for Research and Treatment of Cancer (EORTC) SPLENDOUR Trial

Site-Specific Response and Resistance Patterns in Patients with Advanced Non-Small-Cell Lung Cancer Treated with First-Line Systemic Therapy

Patients with advanced NSCLC have heterogenous responses to immune checkpoint inhibitors (ICIs) with or without chemotherapy. In NSCLC, the impact of the distribution of metastatic sites and the response to systemic therapy combinations remain poorly understood. In a retrospective cohort study of patients with unresectable stage III/IV NSCLC who received first-line systemic therapy, we sought to assess the association between the site of metastases with patterns of response and progression. Data regarding demographics, tumour characteristics (including site, size, and volume of metastases), treatment, and outcomes were examined at two cancer care centres. The endpoints included organ site-specific response rate, objective response rate (ORR), progression-free survival (PFS), and overall survival (OS). Two-hundred and eighty-five patients were included in the analysis. In a multivariate analysis, patients with bone metastases had a reduced ORR, PFS, and OS. Primary resistance was also more likely in patients with bone metastases. Patients with bone or liver metastases had a shorter OS when receiving ICIs with or without chemotherapy, but not with chemotherapy alone, suggesting an immunological basis for therapeutic resistance. A directed assessment of the tumour microenvironment in these locations and a deeper understanding of the drivers of organ-specific resistance to immunotherapy are critical to optimise novel combination therapies and sequencing in these patients.

High bone tumor burden to identify advanced non-small cell lung cancer patients with survival benefit upon bone targeted agents and immune checkpoint inhibitors

BACKGROUND

Bone-targeted agents (BTA), such as denosumab (DN) and zoledronic acid (ZA), have historically reduced the risk of skeletal related events in cancer patients with bone metastases (BM), with no improvement in survival outcomes. In the immunotherapy era, BM have been associated with poor prognosis upon immune-checkpoint inhibitors (ICI). Currently, the impact of bone tumor burden on survival upon BTAs in advanced non-small cell lung cancer (aNSCLC) patients treated with ICI remains unknown.

METHODS

Data from ICI-treated aNSCLC patients with BM (4/2013-5/2022) in one institution were retrospectively collected. BTA-ICI concurrent treatment was defined as BTA administration at any time before or within 90 days from ICI start. High bone tumor burden (HBTB) was defined as ≥ 3 sites of BM. Median OS (mOS) was estimated with Kaplan-Meier. Aikaike's information criterion (AIC) was used to select the best model for data analysis adjusted for clinical variables.

RESULTS

Of 134 patients included, 51 (38 %) received BTA. At a mFU of 39.6 months (m), BTA-ICIs concurrent treatment did not significantly impact on mOS [8.3 m (95% CI 3.9-12.8) versus (vs) 6.8 m (95% CI 4.0-9.6) p = 0.36]; these results were confirmed after adjustment for clinical variables selected by AIC. A multivariate model showed a significant interaction between BTA use and HBTB or radiation therapy to BM. In subgroup analyses, only HBTB confirmed to be associated with significantly longer mOS [8.3 m (95% CI 2.4-14.2) vs 3.5 m (95% CI 2.9-4.1), p = 0.003] and mPFS [3.0 m (95% CI 1.6-4.4) vs 1.8 m (95% CI 1.6-2.0) p = 0.001] upon BTA-ICI concurrent treatment, with the most pronounced OS benefit observed for DN-ICI concurrent regimen [15.2 m (95% CI 0.1-30.7) vs 3.5 m (95% CI 2.9-4.1) p = 0.002].

CONCLUSIONS

In the immunotherapy era, HBTB can identify patients experiencing survival benefit with BTA, especially with DN-ICI combination. HBTB should be included as a stratification factor in the upcoming trials assessing BTA and ICI combinations in patients with aNSCLC and BM.

Optimal timing for local ablative treatment of bone oligometastases in non-small cell lung cancer

Oligometastases is a term commonly used to describe a disease state characterized by a limited number of distant metastases, and represents a transient phase between localized and widespread systemic diseases. This subgroup of stage IV cancer has increased in clinical importance due to the possibility of curative rather than palliative treatment. Among advanced lung cancer patients, 30-40% show bone metastases, and can show complications such as pathological fractures. Many prospective studies have shown efficacy of localized treatment in oligometastatic non-small cell lung cancer (NSCLC) in improving progression-free survival and overall survival. Compared to metastases in other organs, bone metastases are unique in terms of tumor microenvironment and clinical outcomes. Radiotherapy is the most frequently used treatment modality for local ablative treatment for both primary and metastatic lesions. Stereotactic body radiation therapy demonstrated more rapid and effective pain control compared to conventional 3D conformal radiotherapy. Radiotherapy improved outcomes in terms of time-to-skeletal related events skeletal-related events (SRE), hospitalization for SRE, pain relief, and overall survival in patients with bone metastases. Decision on timing of local ablative treatment depends on patient's overall clinical status, treatment goals, potential side effects of each approach, and expected initial responses to systemic anti-cancer treatment.

Bone-modifying agents for non-small-cell lung cancer patients with bone metastases during the era of immune checkpoint inhibitors: A narrative review

During the course of lung cancer progression, bone metastases occur in about 40% of patients. Common complications associated with bone metastases in lung cancer patients include musculoskeletal pain, pathologic fractures, spinal cord compression, and hypercalcemia. We discuss the efficacy of bone-modifying agents (BMAs) in reducing skeletal-related events (SREs) and improving cancer-related outcomes, particularly in patients with stage IV non-small-cell lung cancer with bone metastases. In addition, the combined effects of BMAs with radiotherapy or immunotherapy in reducing SREs in patients with lung cancer and bone metastases are explored.

RANKL and RANK in Cancer Therapy

Receptor activator of nuclear factor-κB (RANK) and its ligand (RANKL) are key regulators of mammalian physiology such as bone metabolism, immune tolerance and antitumor immunity, and mammary gland biology. Here, we explore the multiple functions of RANKL/RANK in physiology and pathophysiology and discuss underlying principles and strategies to modulate the RANKL/RANK pathway as a therapeutic target in immune-mediated cancer treatment.

Incidence of Bone Metastases and Skeletal-Related Events in Patients With EGFR-Mutated NSCLC Treated With Osimertinib

Introduction

Bone metastases are frequent in patients with EGFR-mutated (EGFR+) NSCLC. Skeletal-related events (SREs) are common in these patients; however, no data on SRE in osimertinib-treated patients are reported. We investigated the development of bone metastases and SREs in patients with EGFR+ NSCLC treated with osimertinib.

Methods

This is a retrospective multicenter cohort study that included patients with metastatic EGFR+ NSCLC who were treated with osimertinib between February 2016 and September 2021. Demographics, bone metastases-related outcomes, SREs, treatment efficacy, and overall survival (OS) were collected.

Results

In total, 250 patients treated with osimertinib (43% first line) were included. Of the patients, 51% had bone metastases at initiation of osimertinib. Furthermore, 16% of the patients with bone metastases used bone-targeted agents. Median follow-up from initiation of osimertinib was 23.4 months (95% confidence interval [CI]: 19.9-26.9 mo). During osimertinib treatment, 10% developed new bone metastases or bone progression. Of the patients with bone metastases, 39% had more than or equal to one SREs: 28% developed first SRE before osimertinib treatment, 1% after, and 11% during. Median OS post-bone metastasis was 30.8 months (95% CI: 21.9-39.7). Median OS after first SRE was 31.1 months (95% CI: 15.8-46.5).

Conclusions

Bone metastases and SREs are frequent before and during treatment with osimertinib in EGFR+ NSCLC. Because of these findings and the long OS post-bone metastases, we advocate prescription of bone-targeted agents in these patients and recommend adding bone-specific end points in clinical trials.

Current comprehensive understanding of denosumab (the RANKL neutralizing antibody) in the treatment of bone metastasis of malignant tumors, including pharmacological mechanism and clinical trials

Denosumab, a fully humanized monoclonal neutralizing antibody, inhibits activation of the RANK/RANKL/OPG signaling pathway through competitive binding with RANKL, thereby inhibiting osteoclast-mediated bone resorption. Denosumab inhibits bone loss; therefore, it is used to treat metabolic bone diseases (including postmenopausal osteoporosis, male osteoporosis, and glucocorticoid-induced osteoporosis), in clinical practice. Since then, multiple effects of denosumab have been discovered. A growing body of evidence suggests that denosumab has a variety of pharmacological activities and broad potential in clinical diseases such as osteoarthritis, bone tumors, and other autoimmune diseases. Currently, Denosumab is emerging as a treatment for patients with malignancy bone metastases, and it also shows direct or indirect anti-tumor effects in preclinical models and clinical applications. However, as an innovative drug, its clinical use for bone metastasis of malignant tumors is still insufficient, and its mechanism of action needs to be further investigated. This review systematically summarizes the pharmacological mechanism of action of denosumab and the current understanding and clinical practice of the use of denosumab for bone metastasis of malignant tumors to help clinicians and researchers deepen their understanding of denosumab.

Overall survival and role of programmed death ligand 1 expression in patients with metastatic non-small-cell lung cancer and immunotherapy: an observational study from central Switzerland

BACKGROUND

In clinical trials, therapy with immune checkpoint inhibitors has improved the survival of patients with metastatic non-small-cell lung cancer (NSCLC). These trials were important for drug approval and for defining new treatment standards but the effect of checkpoint inhibitors in patients treated outside of clinical trials is not well known. The goal of this study was to assess the effect of immunotherapy on the overall survival of patients with metastatic NSCLC in the region of central Switzerland.

MATERIALS AND METHODS

The study included 274 patients with histologically confirmed metastatic (stage IV) NSCLC in central Switzerland in the years 2015 to 2018. Patients with NSCLC and actionable driver mutations were excluded. Patients with checkpoint inhibitor treatment (immuno-oncology [IO] group, n = 122) were compared with patients without checkpoint inhibitor treatment (no-IO group, n = 152). Baseline demographics, disease characteristics and therapies applied were collected retrospectively. The primary endpoint was median overall survival calculated either from diagnosis or from the start of checkpoint inhibitor therapy to death or data cut-off (21 July 2021). We used the Kaplan-Meier method and an adjusted Cox proportional-hazards regression model. The expression of programmed-death ligand 1 (PD-L1) on tumour cells was used for exploratory analysis.

RESULTS

Patients had a median age of 68.4 years, most were male (61.7%) and more than half were current or former smokers (65%). A test for PD-L1 expression was available for 55.8% of the tumours. Patients in the IO group were younger than patients in the no-IO group. Among the 122 patients in the IO group, the median overall survival was 15 months (95% confidence interval [CI] 12-20). In the no-IO group, the median overall survival was 4 months (95% CI 3-7) with chemotherapy and 2 months (95% CI 1-2) with best supportive care. Patients with high (≥50%) PD-L1 expression and checkpoint inhibitor therapy had a slightly longer overall survival than patients with low PD-L1 and checkpoint inhibitor therapy.

CONCLUSION

These results suggest that treatment with checkpoint inhibitors improves overall survival in patients with metastatic NSCLC and that PD-L1 expression could have a predictive value in patients treated outside of clinical trials. Further studies are needed to study the magnitude of the benefit of checkpoint inhibitors according to molecular NSCLC subtype.

Assessment of RANK/RANK-L prevalence and clinical significance in NSCLC European Thoracic Oncology Platform Lungscape cohort and SPLENDOUR randomized clinical trial

BACKGROUND

The primary objective of this study is to evaluate the clinical significance of RANK/L expression, in both a retrospective cohort of surgically resected stage I-III NSCLC (Lungscape) and a randomized clinical trial-cohort (SPLENDOUR) of advanced NSCLC treated with chemotherapy alone or in combination with denosumab.

METHODS

RANK-L expression was assessed on tissue microarrays (TMAs) in Lungscape and whole sections in SPLENDOUR, using immunohistochemistry, with H-scores values > 0 indicating positivity. Prevalence of RANK positivity and its association with clinicopathological characteristics, and patient outcome was explored in a subset of the ETOP Lungscape cohort and in SPLENDOUR. Also investigated were the prevalence of RANK overexpression (proportion of positive cancer cells ≥ 50%) in the Lungscape cohort, and RANK-L in the SPLENDOUR trial.

RESULTS

In the Lungscape cohort, RANK expression was assessed at a median follow-up of 46 months (N = 488 patients; 4 centers); 35% were female, 44/49/6% adenocarcinomas (AC)/squamous cell carcinomas (SCC)/other, 48/27/25% with stage I/II/III. Median RFS/TTR/OS were 58/Not reached/74 months. Prevalence of RANK expression was 31% (95%CI:27%-35%); significantly higher in AC: 50% (95%CI:43%-57%) vs SCC: 12% (95%CI:8%-16%) (p < 0.001); more frequent in females (42% vs 25%, p < 0.001) and tumors ≤ 4 cm (35.3% vs 23.3%, p = 0.0065). No association with outcome was found. In the SPLENDOUR trial (463 patients), the prevalence of membranous and cytoplasmic RANK positivity was 34% (95%CI:30%-38%) and 9% (95%CI:7%-12%), respectively, while prevalence for RANK-L was 5% (95%CI:3%-7%) and 36% (95%CI:31%-40%), respectively. Cytoplasmic RANK-L positivity was more common among females (47% vs 31%, p = 0.001) and in non-SCC histology (45% vs 10%, p < 0.0001). At the pre-specified 1% significance level, no prognostic or predictive effect was found.

CONCLUSIONS

Both cohorts indicate that RANK expression is more common in adenocarcinoma/non-squamous NSCLC and in female patients. No prognostic effect is found, and in the clinical trial involving addition of denosumab to chemotherapy no predictive effect is detected.

Association of RANKL and EGFR gene expression with bone metastases in patients with metastatic non-small cell lung cancer

Introduction

Bone metastases are frequent in patients with non-small cell lung cancer (NSCLC). The receptor activator of Nuclear Factor κB (RANK)/RANK ligand (RANKL)/osteoprotegerin (OPG) pathway is important in bone metastases development. Furthermore, epidermal growth factor receptor (EGFR) signaling promotes osteoclast formation and stimulation. The understanding of the biological mechanism of bone metastases development might have implications for treatment strategies. Therefore, we studied whether there is an association between EGFR, RANKL, RANK and OPG gene expression in the tumor and presence of bone metastases in patients with NSCLC.

Methods

From an updated multicenter study, including patients with EGFR mutated (EGFR+), Kirsten rat sarcoma (KRAS+) and EGFR/KRAS wildtype metastatic NSCLC, all patients with available formalin-fixed paraffin-embedded (FFPE) tumor samples were selected. Ribonucleic Acid (RNA) was isolated from these samples and gene expressions of EGFR, RANKL, OPG and RANKL were determined via quantitative Polymerase Chain Reaction (qPCR). Data on demographics, histology and molecular subtyping, sample origin, presence of bone metastasis, SREs and bone progression were collected. Primary endpoint was relation between EGFR, RANK, RANKL, OPG gene expression, RANKL: OPG ratio and bone metastases.

Results

In 73/335 (32% EGFR+, 49% KRAS+, 19% EGFR/KRAS wildtype) samples from unique patients, gene expression analysis could be performed. Of these 73 patients, 46 (63%) had bone metastases at diagnosis or developed bone metastases during the disease course. No association was found between EGFR expression and presence of bone metastases. Patients with bone metastases had a significantly higher RANKL expression and RANKL: OPG ratio compared to those without. An increased RANKL: OPG ratio resulted in a 1.65x increased risk to develop bone metastases, especially in the first 450 days after diagnosis of metastatic NSCLC.

Conclusion

Increased RANKL gene expression and RANKL: OPG ratio, but not EGFR expression, was associated with presence of bone metastases. Additionally, an increased RANKL: OPG gene ratio was associated with a higher incidence of bone metastases development.

Biological and Clinical Aspects of Metastatic Spinal Tumors

Simple Summary

Spine metastases are a common life-threatening complication of advanced-stage malignancies and often result in poor prognosis. Symptomatic spine metastases develop in the course of about 10% of malignant neoplasms. Therefore, it is essential for contemporary medicine to understand metastatic processes in order to find appropriate, targeted therapeutic options. Our literature review aimed to describe the up-to-date knowledge about the molecular pathways and biomarkers engaged in the spine’s metastatic processes. Moreover, we described current data regarding bone-targeted treatment, the emerging targeted therapies, radiotherapy, and immunotherapy used for the treatment of spine metastases. We hope that knowledge comprehensively presented in our review will contribute to the development of novel drugs targeting specific biomarkers and pathways. The more we learn about the molecular aspects of cancer metastasis, the easier it will be to look for treatment methods that will allow us to precisely kill tumor cells.

Abstract

Spine metastases are a common life-threatening complication of advanced-stage malignancies and often result in poor prognosis. Symptomatic spine metastases develop in the course of about 10% of malignant neoplasms. Therefore, it is essential for contemporary medicine to understand metastatic processes in order to find appropriate, targeted therapeutic options. Thanks to continuous research, there appears more and more detailed knowledge about cancer and metastasis, but these transformations are extremely complicated, e.g., due to the complexity of reactions, the variety of places where they occur, or the participation of both tumor cells and host cells in these transitions. The right target points in tumor metastasis mechanisms are still being researched; that will help us in the proper diagnosis as well as in finding the right treatment. In this literature review, we described the current knowledge about the molecular pathways and biomarkers engaged in metastatic processes involving the spine. We also presented a current bone-targeted treatment for spine metastases and the emerging therapies targeting the discussed molecular mechanisms.

Efficacy and safety of concomitant immunotherapy and denosumab in patients with advanced non-small cell lung cancer carrying bone metastases: A retrospective chart review

Background

Synergistic anti-tumor effects were observed in vivo and in vitro when immune checkpoint inhibitors (ICIs) were combined with denosumab. However, the clinical benefit and safety of this synergy have not been adequately evaluated in non-small cell lung cancer (NSCLC).

Methods

Consecutive charts of NSCLC patients with bone metastases between December 2020 and December 2021 in the Chinese National Cancer Center were reviewed. The entire cohort was divided into one experimental group (denosumab + ICIs [DI]) and three control groups (denosumab + non-ICIs [DnI], phosphates + ICIs [PI], phosphates + non-ICIs [PnI]). Real-world objective response rates (ORRs), median progression-free survival (mPFS), skeletal-related events (SREs), and adverse events (AEs) were compared between groups.

Results

A total of 171/410 (41.7%) patients with advanced or recurrent NSCLC carrying bone metastases who received bone-targeted therapy were eligible for analysis. Although the DI group showed a better benefit trend, differences were not statistically significant concerning the therapeutic efficacy among the DI group (n = 40), PI group (n = 74), DnI group (n = 15), and PnI group (n = 42) (ORRs: 47.5%, 43.2%, 33.3%, and 40.5%, respectively, p = 0.799; and mPFS: 378, 190, 170, and 172 days, respectively, p = 0.115; SREs: 5%, 10.8%, 13.3%, and 11.9%, respectively, p = 0.733). Nevertheless, further analysis in the NON-DRIVER cohort revealed a greater benefit for the DI group (p = 0.045). Additionally, the AEs of the DI group were not significantly different from those of the PI, DnI, and PnI groups (AEs: 27.5%, 39.2%, 26.7%, and 28.6%, respectively, p = 0.742). Furthermore, the multivariate analysis revealed the independent prognostic role of DI treatment for PFS in the overall cohort. Within the DI group, we did not observe differences in benefit among different mutational subgroups (p = 0.814), but patients with single-site bone metastasis (p = 0.319) and high PD-L1 expression (p = 0.100) appeared to benefit more, though no significant differences were observed.

Conclusions

Denosumab exhibited synergistic antitumor efficacy without increasing toxicity when used concomitantly with ICIs in patients with advanced non-small cell lung cancer carrying bone metastases.

Bone-Targeted Agents and Metastasis Prevention

The use of bone-targeted treatments has transformed the clinical care of many patients with metastatic breast cancer. In addition, due to the profound effects of bisphosphonates and denosumab on bone physiology and the bone microenvironment, the potential of bone-targeted agents to modify the process of metastasis has been studied extensively. Many adjuvant trials with bisphosphonates in early breast cancer have been performed. Variable outcomes in terms of disease recurrence have been reported, with any treatment benefits apparently influenced by the age and menopausal status of the patients. The Early Breast Cancer Trialists' Collaborative Group (EBCTCG) conducted a meta-analysis of individual patient data from all available randomised trials to investigate this observation further. This meta-analysis failed to show any benefits of adjuvant bisphosphonates in premenopausal women, but highly significant improvements in bone recurrence (RR = 0.72; 95%CI 0.60-0.86, 2p = 0.0002) and breast cancer mortality (RR = 0.82; 95%CI 0.73-0.93, 2p = 0.002) were seen in the 11,767 postmenopausal women included in the meta-analysis. As a result, clinical guidelines recommend the incorporation of adjuvant bisphosphonates that inhibit osteoclast activity into routine clinical care. Denosumab, which has similar effects on bone cell physiology, appears not to consistently influence disease outcomes, perhaps suggesting that it is the "off target" effects of bisphosphonates on immune function and the biological processes involved in metastasis that are important. Predictive biomarkers beyond menopause are being sought and assessment of the transcription factor MAF (mesenchymal aponeurotic fibrosarcoma gene) appears to identify patients able to benefit from the addition of a bisphosphonate to standard adjuvant anticancer therapies.

Overall Survival Improvement in Patients with Epidermal Growth Factor Receptor-Mutated Non-Small Cell Lung Cancer and Bone Metastasis Treated with Denosumab

The impact of an initial skeletal-related event (SRE) and denosumab adjuvant treatment on the survival outcome of epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC) patients with bone metastasis remains unclear. This retrospective study included 400 metastatic EGFR-mutated NSCLC patients. Among 190 bone metastasis patients, 61 had initial SREs and 73 received denosumab. We analyzed patient characteristics, SRE-free survival (SRE-FS), and overall survival (OS). In metastatic EGFR-mutated NSCLC, bone metastasis was associated with a poorer OS (21.7 vs. 33.0 months; p < 0.001). Bone metastasis patients with initial SREs at diagnosis had an even shorter OS, compared with those without initial SRE (15.4 vs. 23.6 months; p = 0.026). Denosumab reduced SRE incidence (hazard ratio (HR) 0.57 (95% confidence interval (CI) 0.34−0.94; p = 0.027) and was associated with improved OS (26.6 vs. 20.1 months; p = 0.015). A multivariate analysis demonstrated that denosumab treatment was correlated with a lower incidence of SRE (HR 0.61 (95% CI 0.37−0.98); p = 0.042) and better OS (HR 0.60 (95% CI 0.41−0.88); p = 0.008). In subgroup analyses, denosumab prolonged SRE-FS (HR 0.36 (95% CI 0.19−0.79); p = 0.009) in patients without initial SREs and was related to a better OS (25.3 vs. 12.9 months; p = 0.016) in patients with initial or pre-existing SREs. Osteonecrosis of the jaw was diagnosed in two patients (2.74%) receiving denosumab. Our study confirmed the association between initial SREs and a worse outcome and provided novel evidence of the survival benefit of denosumab for EGFR-mutated NSCLC patients with bone metastasis.

Oligometastatic Disease in Non-Small-Cell Lung Cancer: An Update

Simple Summary

Approximately 7–50% of patients with non-small-cell lung cancer (NSCLC) develop oligometastases, which are new tumors found in another part of the body, arising from cancer cells of the original tumor that have travelled through the body. In recent years, these patients have been increasingly regarded as a distinct group that could benefit from treatment that intends to cure the disease, rather than palliative care, to achieve a better clinical outcome. Various treatment procedures have been developed for treating NSCLC patients with different oligometastatic sites. In addition, the newly proposed uniform definition for oligometastases as well as ongoing trials may lead to increased appropriate patient selection and evaluation of treatment effectiveness. The aim of this review article is to summarize the latest evidence regarding optimal management strategies for NSCLC patients with oligometastases.

Abstract

Oligometastatic non-small-cell lung cancer (NSCLC) is a distinct entity that is different from localized and disseminated diseases. The definition of oligometastatic NSCLC varies across studies in past decades owing to the use of different imaging modalities; however, a uniform definition of oligometastatic NSCLC has been proposed, and this may facilitate trial design and evaluation of certain interventions. Patients with oligometastatic NSCLC are candidates for curative-intent management, in which local ablative treatment, such as surgery or stereotactic radiosurgery, should be instituted to improve clinical outcomes. Although current guidelines recommend that local therapy for thoracic and metastatic lesions should be considered for patients with oligometastatic NSCLC with stable disease after systemic therapy, optimal management strategies for different oligometastatic sites have not been established. Additionally, the development of personalized therapies for individual patients with oligometastatic NSCLC to improve their quality of life and overall survival should also be addressed. Here, we review relevant articles on the management of patients with oligometastatic NSCLC and categorize the disease according to the site of metastases. Ongoing trials are also summarized to determine future directions and expectations for new treatment modalities to improve patient management.

Immune Checkpoint Inhibitors With or Without Bone-Targeted Therapy in NSCLC Patients With Bone Metastases and Prognostic Significance of Neutrophil-to-Lymphocyte Ratio

Introduction

Bone metastases (BMs) are a negative prognostic factor in patients with non-small cell lung cancer (NSCLC). Although immune-checkpoint inhibitors (ICIs) have dramatically changed the therapeutic landscape of NSCLC, little information is available on BMs from NSCLC treated with ICIs alone or in association with bone-targeted therapy (BTT) such as zoledronate or denosumab.

Methods

From 2014 to 2020, 111 of the 142 patients with BMs secondary to NSCLC extrapolated from the prospective multicenter Italian BM Database were eligible for analysis. Information on blood count, comorbidities, and toxicity was retrospectively collected. The neutrophil-to-lymphocyte ratio (NLR) pre- and post-treatment was calculated. Survival was analyzed using the Kaplan-Meier method, with statistical significance of survival differences assessed using the log-rank test.

Results

Median age was 66 (range, 42-84) years. Performance status (PS) Eastern Cooperative Oncology Group (ECOG) was 0-1 in 79/111 patients. The majority of patients (89.2%) had adenocarcinoma histology. At a median follow-up of 47.4 months, median progression-free (mPFS) and overall survival (mOS) was 4.9 (95%CI, 2.8-10.0) and 11.9 (95%CI, 8.2-14.4) months, respectively. Forty-six (43.4%) patients with BM NSCLC underwent first- or further-line therapy with ICIs: 28 (60.8%) received nivolumab, 9 (19.6%) pembrolizumab, and 9 (19.6%) atezolizumab. Of the 46 patients treated with ICIs, 30 (65.2%) underwent BTT: 24 (80.0%) with zoledronate and 6 (20.0%) with denosumab. The ICI-alone group had an mOS of 15.8 months [95%CI, 8.2-not evaluable (NE)] vs. 21.8 months (95%CI, 14.5-not evaluable) for the ICI plus BTT group and 7.5 (95%CI, 6.1-10.9) months for the group receiving other treatments (p < 0.001). NLR ≤5 had a positive impact on OS.

Conclusion

BTT appears to have a synergistic effect when used in combination with ICIs, improving patient survival.

NF-κB signaling in inflammation and cancer

Since nuclear factor of κ-light chain of enhancer-activated B cells (NF-κB) was discovered in 1986, extraordinary efforts have been made to understand the function and regulating mechanism of NF-κB for 35 years, which lead to significant progress. Meanwhile, the molecular mechanisms regulating NF-κB activation have also been illuminated, the cascades of signaling events leading to NF-κB activity and key components of the NF-κB pathway are also identified. It has been suggested NF-κB plays an important role in human diseases, especially inflammation-related diseases. These studies make the NF-κB an attractive target for disease treatment. This review aims to summarize the knowledge of the family members of NF-κB, as well as the basic mechanisms of NF-κB signaling pathway activation. We will also review the effects of dysregulated NF-κB on inflammation, tumorigenesis, and tumor microenvironment. The progression of the translational study and drug development targeting NF-κB for inflammatory diseases and cancer treatment and the potential obstacles will be discussed. Further investigations on the precise functions of NF-κB in the physiological and pathological settings and underlying mechanisms are in the urgent need to develop drugs targeting NF-κB for inflammatory diseases and cancer treatment, with minimal side effects.

Predictive and Prognostic Biomarkers for Lung Cancer Bone Metastasis and Their Therapeutic Value

Lung cancer is the leading cause of cancer-related death worldwide. Bone metastasis, which usually accompanies severe skeletal-related events, is the most common site for tumor distant dissemination and detected in more than one-third of patients with advanced lung cancer. Biopsy and imaging play critical roles in the diagnosis of bone metastasis; however, these approaches are characterized by evident limitations. Recently, studies regarding potential biomarkers in the serum, urine, and tumor tissue, were performed to predict the bone metastases and prognosis in patients with lung cancer. In this review, we summarize the findings of recent clinical research studies on biomarkers detected in samples obtained from patients with lung cancer bone metastasis. These markers include the following: (1) bone resorption-associated markers, such as N-terminal telopeptide (NTx)/C-terminal telopeptide (CTx), C-terminal telopeptide of type I collagen (CTx-I), tartrate-resistant acid phosphatase isoform 5b (TRACP-5b), pyridinoline (PYD), and parathyroid hormone related peptide (PTHrP); (2) bone formation-associated markers, including total serum alkaline phosphatase (ALP)/bone specific alkaline phosphatase(BAP), osteopontin (OP), osteocalcin (OS), amino-terminal extension propeptide of type I procollagen/carboxy-terminal extension propeptide of type I procollagen (PICP/PINP); (3) signaling markers, including epidermal growth factor receptor/Kirsten rat sarcoma/anaplastic lymphoma kinase (EGFR/KRAS/ALK), receptor activator of nuclear factor κB ligand/receptor activator of nuclear factor κB/osteoprotegerin (RANKL/RANK/OPG), C-X-C motif chemokine ligand 12/C-X-C motif chemokine receptor 4 (CXCL12/CXCR4), complement component 5a receptor (C5AR); and (4) other potential markers, such as calcium sensing receptor (CASR), bone sialoprotein (BSP), bone morphogenetic protein 2 (BMP2), cytokeratin 19 fragment/carcinoembryonic antigen (CYFRA/CEA), tissue factor, cell-free DNA, long non-coding RNA, and microRNA. The prognostic value of these markers is also investigated. Furthermore, we listed some clinical trials targeting hotspot biomarkers in advanced lung cancer referring for their therapeutic effects.

Combined, patient-level, analysis of two randomised trials evaluating the addition of denosumab to standard first-line chemotherapy in advanced NSCLC - The ETOP/EORTC SPLENDOUR and AMGEN-249 trials

INTRODUCTION

The efficacy of adding denosumab to standard first-line chemotherapy for advanced NSCLC patients has been evaluated in two separate randomised trials (SPLENDOUR and AMGEN-249). In this pooled analysis, we will assess the combination-treatment effect in the largest available population, in order to conclude about the potential impact of denosumab in NSCLC.

METHODS

Both trials included in this combined analysis, were randomised (SPLENDOUR 1:1, AMGEN-249 2:1) multi-centre trials stratified by histology, bone metastasis, geographical region and for SPLENDOUR only, ECOG PS. Cox proportional hazards models, were used to assess the treatment effect with respect to overall survival (OS; primary endpoint) and progression-free survival (PFS; secondary endpoint). Heterogeneity between trials was assessed, and subgroup analyses were performed.

RESULTS

The pooled analysis was based on 740 randomised patients (SPLENDOUR:514; AMGEN-249:226), with 407 patients in the chemotherapy-denosumab arm and 333 in the chemotherapy-alone arm. In the chemotherapy-denosumab arm, at a median follow-up of 22.0 months, 277 (68.1%) deaths were reported with median OS 9.2 months (95%CI:[8.0-10.7]), while in the chemotherapy-alone arm, with similar median follow-up of 20.3 months, 230 (69.1%) deaths with median OS 9.9 months (95%CI:[8.2-11.2]). No significant denosumab effect was found (HR = 0.98; 95%CI:[0.82-1.18]; P = 0.85). Among subgroups, interaction was found between treatment and histology subtypes (P = 0.020), with a statistically significant benefit in the squamous group (HR = 0.70; 95%CI:[0.49-0.98]; P = 0.038), from 7.6 to 9.0 months median OS. With respect to PFS, 363 (89.2%) and 298 (89.5%) events were reported in the chemotherapy-denosumab and chemotherapy-alone arms, respectively, with corresponding medians 4.8 months (95%CI:[4.4-5.3]) and 4.9 months (95%CI:[4.3-5.4]). HR for PFS was 0.97(95%CI:[0.83-1.15]; P = 0.76), indicating that no significant denosumab benefit existed for PFS.

CONCLUSION

In this pooled analysis, no statistically significant improvement was shown in PFS/OS with the combination of denosumab and chemotherapy for advanced NSCLC and no meaningful benefit in any of the subgroups.

Does denosumab offer survival benefits? -Our experience with denosumab in metastatic non-small cell lung cancer patients treated with immune-checkpoint inhibitors

Background

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of non-small-cell lung cancer (NSCLC). Denosumab is a humanized monoclonal antibody to RANK ligand used to prevent skeletal-related events of bone metastases in solid tumors. We are reporting the clinical outcomes in our NSCLC patients who received RANKL inhibitor in combination with ICIs.

Methods

This observational study used retrospective data from a tertiary cancer center from 2015–2020. Stage IV non-small cell lung cancer patients who received denosumab within 30 days of ICIs (pembrolizumab, nivolumab, atezolizumab, ipilimumab) were included. Kaplan-Meier curves were obtained for survival analysis.

Results

We identified 69 patients and all had skeletal metastases, and 37.7% had brain metastases. Median OS was 6.3 months and median PFS was 2.8 months, with overall response rate (ORR) of 18.8% and disease control rate (DCR) of 40.6%. Median OS in patients with concomitant denosumab and ICIs more than 3 months was 11.5 months, comparing to 3.6 months in patients with <3 months of concomitant therapy (P=0.0005). OS and PFS did not differ with respect to brain metastases or number of skeletal metastases. However, the duration of ICIs and denosumab overlap was associated with improved OS and PFS. Among the 18.8% of patients who achieved complete response (CR) and partial response (PR), six-month survival rate was 100% and one-year survival rate was 69.2%. Most of the patients tolerated denosumab well, and hypocalcemia was the most commonly reported side effect.

Conclusions

Patients receiving combination therapy did not perform poorly comparing to published studies despite of poor prognostic features such as brain metastases and numerous skeletal metastases. Although we did notice potential benefit of the longer duration of concomitant use of ICI and denosumab, future prospective clinical trials are needed to evaluate the synergistic effect of RANKL inhibitors/ICI and if duration of RANKL inhibitors matters.

Prognostic Factors in Lung Adenocarcinoma with Bone Metastasis Treated with EGFR-TKIs

Background and Objectives: Patients who have advanced lung cancer and bone metastasis (BM) often suffer from skeletal-related events (SREs) that lead to poor quality of life and poor prognosis. Our study aimed to investigate the prognostic factors in patients with BM from epidermal growth factor receptor (EGFR) mutation-positive lung adenocarcinoma. Materials and Methods: This retrospective study included 77 lung adenocarcinoma patients with synchronous BM. These patients had first-line EGFR tyrosine kinase inhibitors (EGFR-TKIs) between January 2017 and December 2019. Among them, 42 patients were treated with 120 mg of subcutaneous denosumab monthly. We investigated their baseline characteristics, cancer management, SREs, progression-free survival (PFS), and overall survival (OS). Results: The PFS in the patients treated with or without denosumab were 10.1 vs. 12.5 months (p = 0.971). The median OS was 26.9 vs. 29.5 months (p = 0.967) in no denosumab and denosumab groups, respectively. Univariate analyses showed benefit of afatinib in PFS and good performance status in OS. Conclusion: Those patients that took afatinib as first-line EGFR-TKIs had significantly longer PFS than those treated with other TKIs. Denosumab had no prognostic effect on PFS or OS.

The Roadmap of RANKL/RANK Pathway in Cancer

The receptor activator of the nuclear factor-κB ligand (RANKL)/RANK signaling pathway was identified in the late 1990s and is the key mediator of bone remodeling. Targeting RANKL with the antibody denosumab is part of the standard of care for bone loss diseases, including bone metastases (BM). Over the last decade, evidence has implicated RANKL/RANK pathway in hormone and HER2-driven breast carcinogenesis and in the acquisition of molecular and phenotypic traits associated with breast cancer (BCa) aggressiveness and poor prognosis. This marked a new era in the research of the therapeutic use of RANKL inhibition in BCa. RANKL/RANK pathway is also an important immune mediator, with anti-RANKL therapy recently linked to improved response to immunotherapy in melanoma, non-small cell lung cancer (NSCLC), and renal cell carcinoma (RCC). This review summarizes and discusses the pre-clinical and clinical evidence of the relevance of the RANKL/RANK pathway in cancer biology and therapeutics, focusing on bone metastatic disease, BCa onset and progression, and immune modulation.

Updates in Management of Bone Metastatic Disease in Primary Solid Tumors with Systemic Therapies

PURPOSE OF REVIEW

The purpose of this review is to highlight novel and impactful discoveries in systemic treatment of bone metastatic disease in solid tumors published within the past 5 years.

RECENT FINDINGS

Major developments in systemic treatment of bone metastatic disease in solid tumors include evidence that decreasing frequency of dosing zoledronic acid in metastatic breast and prostate cancer maintains efficacy in preventing skeletal-related events while decreasing costs. The landmark findings on the use of Radium-223 to treat metastatic prostate cancer were reported in 2013. Recently, it has been found that not all systemic therapy combinations with Radium-223 are necessarily safe or effective unless bone-targeted therapy is also included in the regimen. More cost-effective dosing intervals of zoledronic acid and efficacy and safety nuances of combination radiopharmaceutical and chemotherapy treatment have been better delineated.

Advances in radiotherapy in bone metastases in the context of new target therapies and ablative alternatives: A critical review

In patients with bone metastases (BM), radiotherapy (RT) is used to alleviate symptoms, reduce the risk of fracture, and improve quality of life (QoL). However, with the emergence of concepts like oligometastases, minimal invasive surgery, ablative therapies such as stereotactic ablative RT (SABR), radiosurgery (SRS), thermal ablation, and new systemic anticancer therapies, there have been a paradigm shift in the multidisciplinary approach to BM with the aim of preserving mobility and function survival. Despite guidelines on using single-dose RT in uncomplicated BM, its use remains relatively low. In uncomplicated BM, single-fraction RT produces similar overall and complete response rates to RT with multiple fractions, although it is associated with a higher retreatment rate of 20% versus 8%. Complicated BM can be characterised as the presence of impending or existing pathologic fracture, a major soft tissue component, existing spinal cord or cauda equina compression and neuropathic pain. The rate of complicated BM is around 35%. Unfortunately, there is a lack of prospective trials on RT in complicated BM and the best dose/fractionation regimen is not yet established. There are contradictory outcomes in studies reporting BM pain control rates and time to pain reduction when comparing SABR with Conventional RT. While some studies showed that SABR produces a faster reduction in pain and higher pain control rates than conventional RT, other studies did not show differences. Moreover, the local control rate for BM treated with SABR is higher than 80% in most studies, and the rate of grade 3 or 4 toxicity is very low. The use of SABR may be preferred in three circumstances: reirradiation, oligometastatic disease, and radioresistant tumours. Local ablative therapies like SABR can delay change or use of systemic therapy, preserve patients' Qol, and improve disease-free survival, progression-free survival and overall survival. Moreover, despite the potential benefit of SABR in oligometastatic disease, there is a need to establish the optial indication, RT dose fractionation, prognostic factors and optimal timing in combination with systemic therapies for SABR. This review evaluates the role of RT in BM considering these recent treatment advances. We consider the definition of complicated BM, use of single and multiple fractions RT for both complicated and uncomplicated BM, reirradiation, new treatment paradigms including local ablative treatments, oligometastatic disease, systemic therapy, physical activity and rehabilitation.

Reporting of Incidence and Outcome of Bone Metastases in Clinical Trials Enrolling Patients with Epidermal Growth Factor Receptor Mutated Lung Adenocarcinoma-A Systematic Review

Bone metastases, occurring in 30-60% of patients with non-small cell lung cancer (NSCLC), are associated with decreased survival, cancer-induced bone pain, and skeletal-related events (SREs). Those with an activating epidermal growth factor mutation (EGFR+) seem to be more prone to develop bone metastases. To gain more insight into bone metastases-related outcomes in EGFR+ NSCLC, we performed a systematic review on Pubmed (2006-2021). Main inclusion criteria: prospective, phase II/III trials evaluating EGFR-tyrosine kinase inhibitors, ≥10 EGFR+ patients included, data on bone metastases and/or bone-related outcomes available. Out of 663 articles, 21 (3176 EGFR+ patients) met the eligibility criteria; 4 phase III (one double blind), 17 phase II trials (three randomized) were included. In seven trials dedicated bone imaging was performed at baseline. Mean incidence of bone metastases at diagnosis was 42%; 3-33% had progression in the bone upon progression. Except for one trial, it was not specified whether the use of bone target agents was permitted, and in none of the trials, occurrence of SREs was reported. Despite the high incidence of bone metastases in EGFR+ adenocarcinoma, there is a lack of screening for, and reporting on bone metastases in clinical trials, as well as permitted bone-targeted agents and SREs.

Second-line therapy improves overall survival in primary refractory non-small cell lung cancer (NSCLC) patients

Background

The effect of palliative chemotherapy for non-small cell lung cancer (NSCLC) is well established. Recently, immune checkpoint inhibitors have shown promising efficacy in NSCLC patients. However, little is known about the efficacy of cytotoxic chemotherapy in patients whose tumors are refractory to first-line chemotherapy. We investigated the outcome of all consecutive and unselected patients receiving palliative chemotherapy in a single institution to assess the efficacy of second-line chemotherapy in primary refractory NSCLC.

Patients and methods

Patients with metastatic NSCLC diagnosed between 1990 and 2016 were assessed. Outcome parameters were collected and patients were characterized as either having primary progressive disease or clinical benefit [CB; defined as complete/partial remission (CR, PR) or stable disease (SD)]. Probabilities of survival were calculated using the Kaplan–Meier estimator. The log-rank test was used for comparing groups. Cox models were used to explore the prognostic value of covariables.

Results

The analysis included 576 patients. Median overall survival (OS) was 9.5 months [95% confidence interval (CI) 8.47-10.47]; 62.7% of patients were treated with a platinum-based first-line therapy. Two hundred twenty-two patients (38.5%) were primary refractory to first-line therapy. Median OS was significantly shorter for those patients [7.4 versus 11.5 months, hazard ratio (HR) 1.61 (95% CI 1.34-1.93), P < 0.0001]. Poorer initial performance status was significantly associated with primary refractory disease (P = 0.015). Eighty-one (36.5%) primary refractory patients received a second-line therapy. Median OS was significantly longer for refractory patients receiving second-line therapy versus best supportive care [10.1 versus 5.0 months, HR 0.53 (95% CI 0.40-0.72), P < 0.0001].

Conclusions

Nearly 40% of patients are primary refractory to palliative first-line therapy and have a poor prognosis. Active second-line therapy can significantly improve the outcome. Therefore, patients with primary refractory NSCLC should be offered further active therapy. These real-life data for primary refractory patients form the basis for further research in sequencing of current palliative treatment options.

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Unselected patients with metastatic NSCLC have a poor outcome despite recent therapeutic advances.

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A substantial number of NSCLC patients in a real-world setting is refractory to primary treatment.

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Primary refractory patients have a poor prognosis.

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It is unclear whether patients with primary refractory NSCLC should receive further active systemic treatment.

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Our work shows that further treatment of primary refractory patients can lead to an improvement of the prognosis.

Risk factors for skeletal-related events in non-small cell lung cancer patients treated with bone-modifying agents

PURPOSE

The risk factors for skeletal-related events (SREs) among non-small cell lung cancer (NSCLC) patients during treatment with bone-modifying agents (BMAs) are not yet well-understood.

METHODS

The medical records of 238 consecutive NSCLC patients treated with BMAs, including zoledronic acid and denosumab, at the Chiba University Hospital from 2012 to 2016 were reviewed in the present study. SREs were defined as either pathologic fractures, spinal cord compression, the need for bone irradiation or surgery, or hypercalcemia. The risk factors for earlier occurrence of the first SRE from the time of the first bone metastasis diagnosis after the initiation of BMA treatment were identified.

RESULTS

Of the 238 included patients, 92% (n = 220) had a performance status (PS) of 0-2 at diagnosis of bone metastasis. Forty-eight (20%) patients developed at least one SRE. The most common first SRE was the need for bone irradiation surgery (n = 27, 56%). Significant risk factors included poor PS (hazard ratio [HR]: 4.36; p = .024), male sex (HR: 2.17; p = .022), and the use of zoledronic acid (HR: 1.91; p = .032). The overall survival (OS) from the first bone metastasis diagnosis was 394 days (95% confidence interval [CI]: 331-465). The OS of patients with PS 3 and 4 at the diagnosis of bone metastasis (median: 36 days; 95% CI: 13-50) was significantly (p < 0.0001) shorter than that of patients with PS 0-2 (median: 411 days; 95% CI: 354-558) (HR: 4.53; 95% CI: 2.62-7.35).

CONCLUSIONS

Careful observation is needed for patients with the identified risk factors, which include poor PS and male sex, despite the BMA treatment.

Role of RANKL in cancer development and metastasis

Bone metastasis involves tumor-induced osteoclast activation, resulting in skeletal tumor progression as well as skeletal disorders. Aberrant expression of receptor activator of NF-κB ligand (RANKL), an essential cytokine for osteoclast differentiation, induced by the metastatic tumor cells is responsible for the pathological bone resorption in bone metastasis. A fully human anti-RANKL neutralizing antibody has been developed to block osteoclast activation and is now used for the treatment of patients with bone metastasis and multiple myeloma. On the other hand, numerous studies have revealed that the RANKL/RANK system also contributes to primary tumorigenesis as well as metastasis through osteoclast-independent processes. Furthermore, emerging clinical and preclinical evidence has suggested anti-tumor immune effects of RANKL blockade when added to immune checkpoint inhibitor therapies. Study on the pleiotropic functions of RANKL in tumorigenesis and metastasis is now expanding beyond the bone field and has been established as one of the most important areas of "RANKL biology".

Non-Radiation Based Early Pain Relief Treatment Options for Patients With Non-Small Cell Lung Cancer and Cancer Induced Bone Pain: A Systematic Review

INTRODUCTION

Cancer induced bone pain (CIBP) is frequent in patients with non-small cell lung cancer (NSCLC). Radiation therapy continues to be the gold standard for treatment of painful bone metastases, however only a limited number of metastases can be irradiated. We evaluated non-radiation based early CIBP relief options in NSCLC through a systematic review.

METHODS

Systematic review including all prospective articles published between 01-1994 and 06-2020 on Pubmed, Cochrane Library and ClinicalTrials.gov database. Inclusion: non-radiation based trials evaluating CIBP early pain relief options (initially defined as pain score evaluated within two weeks, because of no randomized trials, later inclusion broadened to pain score evaluated within six weeks) in ≥10 NSCLC patients. Radioisotope trials were excluded as these treatments have interactions with systemic anticancer therapy.

RESULTS

188 articles were found; 10 articles (6 randomized controlled (4 double blinded), 1 phase II single-arm, and 3 prospective trials) fulfilled the inclusion criteria. Six of these trials consisted of ≥2 treatment arms, whereas the others were single-arm studies. In total, 554 NSCLC patients were evaluated in these trials. The included trials were very heterogeneous regarding evaluated treatment options, methods of pain measuring, and endpoints. No high-level evidence for specific early pain relief treatment options was found.

DISCUSSION

Non-radiation based studies evaluating treatment options to rapidly reduce CIBP in NSCLC are scarce. This systematic review shows that there is no high-level evidence to recommend a specific treatment for early pain relief. Future research should focus on early pain relief treatment options for CIBP in NSCLC.