Immune checkpoint blockade for advanced non-small cell lung cancer: challenging clinical scenarios

Radiotherapy for unresectable locally advanced non-small cell lung cancer: a narrative review of the current landscape and future prospects in the era of immunotherapy

Significant recent advances have occurred in the use of radiation therapy for locally advanced non-small cell lung cancer (LA-NSCLC). In fact, the past few decades have seen both therapeutic gains and setbacks in the evolution of radiotherapy for LA-NSCLC. The PACIFIC trial has heralded a new era of immunotherapy and has raised important questions for future study, such as the future directions of radiation therapy for LA-NSCLC in the era of immunotherapy. Modern radiotherapy techniques such as three-dimensional (3D) conformal radiotherapy and intensity-modulated radiotherapy (IMRT) provide opportunities for improved target conformity and reduced normal-tissue exposure. However, the low-dose radiation volume brought by IMRT and its effects on the immune system deserve particular attention when combing radiotherapy and immunotherapy. Particle radiotherapy offers dosimetric advantages and exhibits great immunoregulatory potential. With the ongoing improvement in particle radiotherapy techniques and knowledge, the combination of immunotherapy and particle radiotherapy has tremendous potential to improve treatment outcomes. Of particular importance are questions on the optimal radiation schedule in the settings of radio-immunotherapy. Strategies for the reduction of the irradiated field such as involved-field irradiation (IFI) and omission of clinical target volume (CTV) hold promise for better preservation of immune function while not compromising locoregional and distant control. In addition, different dose-fractionation regimens can have diverse effects on the immune system. Thus, prospective trials are urgently needed to establish the optimal dose fractionation regimen. Moreover, personalized radiotherapy which allows the tailoring of radiation dose to each individual's genetic background and immune state is of critical importance in maximizing the benefit of radiation to patients with LA-NSCLC.

Adverse impact of bone metastases on clinical outcomes of patients with advanced non-small cell lung cancer treated with immune checkpoint inhibitors

Background

Bone metastasis (BoM) is common in patients with advanced non‐small cell lung cancer (NSCLC) and considered as one of the negative prognostic factors. However, the impact of BoM on clinical outcomes of patients with advanced NSCLC treated with immune checkpoint inhibitors (ICIs) remains unclear.

Methods

A total of 103 patients treated with ICI monotherapy and 101 patients treated with ICIs combined with chemotherapy or antiangiogenesis therapy were retrospectively analyzed. The differences in progression‐free survival (PFS), overall survival (OS) and objective response rate (ORR) between BoM+ and BoM− were investigated.

Results

Of those 101 patients who received combination therapy, no significant difference between BoM− and BoM+ in terms of both median PFS and median OS (median PFS, 10.1 vs. 12.1 months, P = 0.6; median OS, NR vs. 24.6 months, P = 0.713) was determined. In contrast, of the 103 patients who received ICI monotherapy, BoM+ patients had an inferior PFS (4.2 vs. 6.7 months, P = 0.0484) and OS (12.5 vs. 23.9 months, P = 0.0036) compared with BoM− patients. The univariate and multivariate analysis in the ICI monotherapy group also identified BoM as an independent factor attenuating the efficacy of ICI monotherapy. Of all BoM+ patients who received ICI monotherapy, neither palliative radiotherapy nor bisphosphonate drugs improved OS (palliative radiotherapy: 12.5 vs. 16.7 months, P = 0.487; bisphosphonate drugs: 12.5 vs. 9.7 months, P = 0.568).

Conclusions

BoM attenuated the efficacy of ICI monotherapy in patients with advanced NSCLC. Of BoM+ patients who received ICI monotherapy, neither palliative radiotherapy nor bisphosphonate drugs improved OS. Other therapeutic strategies are needed for patients with BoM.

NLCIPS: Non-Small Cell Lung Cancer Immunotherapy Prognosis Score

Introduction

Currently in China, many immune checkpoint inhibitors (ICIs) have been approved for the treatment of non-small cell lung cancer (NSCLC). Some patients can not benefit from ICIs, and approximately 50% of patients have immunotherapy-related toxicity. Therefore, it is necessary to monitor carefully the selection of immunotherapy population using biomarkers to maximize the benefit of patients with NSCLC.

Methods

A prospective analysis was performed on patients with advanced NSCLC who were treated with ICIS at our hospital from March 2018 to June 2019, up to the follow-up deadline of December 31, 2019. The primary end points were overall survival (OS) and progression-free survival (PFS), and the secondary end points were objective response rate and disease control rate. A lasso regression was used for the univariate analysis, and Cox regression analysis was used for the multivariate analysis. An efficacy prediction line chart was developed.

Results

A total of 63 patients were included in the study. The median PFS was 7.0 months (95% CI, 5.0–11.0) and did not reach the median OS. According to the lasso regression, significant univariate factors were smoking index, PD-ligand 1 expression, and neutrophil to lymphocyte ratio (NLR). According to the multivariate analysis, the Cox proportional hazards model showed that smoking index and NLR are independent predictors of PFS in immunotherapy. A model comprised of independent predictors was developed based on a multivariate logical analysis of the main cohort—non-small cell lung cancer immunotherapy prognosis score. This model is shown as a nomogram with a C-index of 0.801 (95% CI, 0.744, 0.858), which has high prediction accuracy.

Conclusion

This predictive model, including NLR and smoking index, can achieve a 1-year PFS in immunotherapy of patients. PD-1 inhibitors have been demonstrated to be effective and safe in the clinical treatment of patients with NSCLC.

The Agnostic Role of Site of Metastasis in Predicting Outcomes in Cancer Patients Treated with Immunotherapy

Immune checkpoint inhibitors have revolutionized treatment and outcome of melanoma and many other solid malignancies including non-small cell lung cancer (NSCLC) and renal cell carcinoma (RCC). Unfortunately, only a minority of patients have a long-term benefit, while the remaining demonstrate primary or acquired resistance. Recently, it has been demonstrated that the prevalence of programmed death-ligand 1 (PD-L1) and tumor-infiltrating lymphocytes (TILs) varies based on the anatomical site of metastases. In particular, liver seems to have more immunosuppressive microenvironment while both the presence of lymph nodal disease and lung metastases seem to have the highest prevalence of PD-L1 and TILs. The aim of the present study is to investigate the possible role of site of metastases as a predictive factor for response or resistance to immunotherapy in several types of cancer. In this multicenter retrospective study, we enrolled patients with metastatic NSCLC, melanoma, RCC, urothelial, merkel carcinoma, and colon cancer who received immunotherapy from April 2015 to August 2019. Major clinicopathological parameters were retrieved and correlated with patients’ survival outcomes in order to assess their prognostic value and build a useful tool to assist in the decision-making process. A total of 291 patients were included in this study. One hundred eighty-seven (64%) patients were male and 104 (36%) female. The tumor histology was squamous NSCLC in 56 (19%) patients, non-squamous NSCLC in 99 (34%) patients, melanoma in 101 (35%) patients, RCC in 28 (10%) patients, and other tumors in the remaining 7 (2%) patients. The number of metastatic sites was 1 in 103 patients (35%), 2 in 104 patients (36%) and 3 in 84 patients (29%). Out of 183 valuable patients, the entity of response was complete response (CR), partial response (PR), stable disease (SD), and progression disease (PD) in 15, 53, 31, and 79 patients, respectively. Using an univariate analysis (UVA), tumor burden (p = 0.0004), the presence of liver (p = 0.0009), bone (p = 0.0016), brain metastases (p < 0.0001), the other metastatic sites (p = 0.0375), the number of metastatic sites (p = 0.0039), the histology (p = 0.0034), the upfront use of immunotherapy (p = 0.0032), and Eastern Cooperative Oncology Group (ECOG) Perfomance status (PS) ≥ 1 (p < 0.0001) were significantly associated with poor overall survival (OS). Using a multivariate analysis (MVA) the presence of liver (p = 0.0105) and brain (p = 0.0026) metastases, the NSCLC diagnosis (p < 0.0001) and the ECOG PS (p < 0.0001) resulted as significant prognostic factors of survival. Regarding the progression free survival (PFS), using a UVA of the tumor burden (p = 0.0004), bone (p = 0.0098) and brain (p = 0.0038) metastases, the presence of other metastatic sites (p = 0.0063), the number of metastatic sites (p = 0.0007), the histology (p = 0.0007), the use of immunotherapy as first line (p = 0.0031), and the ECOG PS ≥ 1 (p ≤ 0.0001) were associated with a lower PFS rate. Using an MVA, the presence of brain (p = 0.0088) and liver metastases (p = 0.024) and the ECOG PS (p < 0.0001) resulted as predictors of poor PFS. Our study suggests that the site of metastases could have a role as prognostic and predictive factor in patients treated with immunotherapy. Indeed, regardless of the histology, the presence of liver and brain metastases was associated with a shorter PFS and OS, but these results must be confirmed in further studies. In this context, a deep characterization of microenvironment could be crucial to prepare patients through novel strategies with combination or sequential immunotherapy in order to improve treatment response.

EPSILoN: A Prognostic Score Using Clinical and Blood Biomarkers in Advanced Non-Small-cell Lung Cancer Treated With Immunotherapy

BACKGROUND

Second-line immunotherapy (IO) has shown an overall survival benefit. However, only 18% to 20% of patients with advanced non-small-cell lung cancer (aNSCLC) will respond, with a median progression-free survival (PFS) of 2 to 4 months. Thus, biomarkers to select those patients most likely to benefit from IO are greatly needed.

PATIENTS AND METHODS

We conducted a retrospective analysis of 154 patients with aNSCLC who had received anti-programmed cell death 1 therapy as second line or further treatment. We assessed the absolute neutrophil, lymphocyte, monocyte, and eosinophil counts at baseline (T0) and the second (T1) and third (T2) cycles. The neutrophil/lymphocyte ratio (NLR), derived-NLR (dNLR), lymphocyte/monocyte ratio (LMR), and their percentage of change at T1 and T2 compared with T0 were evaluated. The clinical characteristics and lactate dehydrogenase (LDH) level were also considered. Univariate and multivariate analyses were performed. Significant biomarkers for PFS on multivariate analysis were combined in a prognostic score.

RESULTS

For overall survival, the negative prognostic biomarkers were Eastern Cooperative Oncology Group (ECOG) performance status (PS) 2, NLR at T0, and dNLR at T1; the LMR at T0, T1, and T2 was identified as a positive prognostic biomarker. For PFS, the negative prognostic biomarkers were ECOG PS 2, liver metastases, NLR at T0, dNLR at T1 and T2, and ≥ 30% increase of NLR from T0 to T1; the positive prognostic biomarkers were heavy smoking, LDH, and LMR at T2. The ≥ 30% increase of LMR from T0 to T1 and T0 to T2 correlated with the overall response rate. A prognostic score (EPSILoN score; smoking, ECOG PS, liver metastases, LDH, NLR) identified 3 prognostic groups (median PFS, 10.2, 4.9, and 1.7 months, respectively; P < .001).

CONCLUSIONS

The EPSILoN score combines 5 baseline clinical and blood biomarkers and can help to identify patients with aNSCLC who will most likely benefit from second-line IO. Further studies are warranted.

An Exceptional Responder to Nivolumab in Metastatic Non-Small-Cell Lung Cancer: A Case Report and Literature Review of Long-Term Survivors

Background

Exceptional responders to immune checkpoint inhibitors in metastatic non-small-cell lung cancer (NSCLC) are rare. Furthermore, the optimal duration of immunotherapy in patients who achieve complete remission and the benefit of rechallenge after recurrence remain unknown. Studying the clinical course of exceptional responders can help identify potential predictors of response to immunotherapy and further fine-tune our management algorithms in the absence of standard of care in challenging scenarios.

Case Presentation

We highlight the case of a 73-year-old Vietnam War Veteran with active tobacco dependence who achieved complete response with nivolumab for metastatic NSCLC after four prior lines of chemotherapy. Nivolumab was discontinued after 10 cycles due to immune-mediated hepatitis that resolved with steroids. He remained in complete remission for 14 months while off therapy. Then, his tumor recurred twice locally in the mediastinum and he again achieved complete and durable responses after each recurrence with radiotherapy. Due to recurrence in both lungs one year later, he was rechallenged with nivolumab and achieved partial response after two months of therapy. He continues to do well five and a half years since his initial diagnosis of de novo metastatic NSCLC.

Conclusion

Optimal management of exceptional responders to immune checkpoint inhibitors in metastatic NSCLC is largely unknown. Our case report adds to the limited data supporting the use of localized therapy for oligometastatic recurrences and rechallenge with immunotherapy for widespread disease in achieving disease control and long-term survival.

EPSILoN: A Prognostic Score for Immunotherapy in Advanced Non-Small-Cell Lung Cancer: A Validation Cohort

BACKGROUND

Beyond programmed death ligand 1 (PD-L1), no other biomarkers for immunotherapy are used in daily practice. We previously created EPSILoN (Eastern Cooperative Oncology Group performance status (ECOG PS), smoking, liver metastases, lactate dehydrogenase (LDH), neutrophil-to-lymphocyte ratio (NLR)) score, a clinical/biochemical prognostic score, in 154 patients treated with second/further-line immunotherapy. This study's aim was to validate EPSILoN score in a different population group.

METHODS

193 patients were included at National Cancer Institute of Milan (second-line immunotherapy, 61%; further-line immunotherapy, 39%). Clinical/laboratory parameters such as neutrophil-to-lymphocyte ratio and lactate dehydrogenase levels were collected. Kaplan-Meier and Cox hazard methods were used for survival analysis.

RESULTS

Overall median progression-free survival and median overall survival were 2.3 and 7.6 months, respectively. Multivariate analyses for Progression-Free Survival (PFS) identified heavy smokers (hazard ratio (HR) 0.71, p = 0.036) and baseline LDH < 400 mg/dL (HR 0.66, p = 0.026) as independent positive factors and liver metastases (HR 1.48, p = 0.04) and NLR ≥ 4 (HR 1.49, p = 0.029) as negative prognostic factors. These five factors were included in the EPSILoN score which was able to stratify patients in three different prognostic groups, high, intermediate and low, with PFS of 6.0, 3.8 and 1.9 months, respectively (HR 1.94, p < 0.001); high, intermediate and low prognostic groups had overall survival (OS) of 24.5, 8.9 and 3.4 months, respectively (HR 2.40, p < 0.001).

CONCLUSIONS

EPSILoN, combining five baseline clinical/blood parameters (ECOG PS, smoking, liver metastases, LDH, NLR), may help to identify advanced non-small-cell lung cancer (aNSCLC) patients who most likely benefit from immune checkpoint inhibitors (ICIs).

Sites of metastasis and association with clinical outcome in advanced stage cancer patients treated with immunotherapy

Background

Selecting the appropriate patients to receive immunotherapy (IO) remains a challenge due to the lack of optimal biomarkers. The presence of liver metastases has been implicated as a poor prognostic factor in patients with metastatic cancer. We investigated the association between sites of metastatic disease and clinical outcomes in patients receiving IO.

Methods

We conducted a retrospective review of 90 patients treated on IO-based phase 1 clinical trials at Winship Cancer Institute of Emory University between 2009 and 2017. Overall survival (OS) and progression-free survival (PFS) were measured from the first dose of IO to date of death or hospice referral and clinical or radiographic progression, respectively. Clinical benefit (CB) was defined as a best response of complete response (CR), partial response (PR), or stable disease (SD). Univariate analysis (UVA) and Multivariate analysis (MVA) were carried out using Cox proportional hazard model or logistic regression model. Covariates included age, whether IO is indicated for the patient’s histology, ECOG performance status, Royal Marsden Hospital (RMH) risk group, number of metastatic sites, and histology.

Results

The median age was 63 years and 53% of patients were men. The most common histologies were melanoma (33%) and gastrointestinal cancers (22%). Most patients (73.3%) had more than one site of distant metastasis. Sites of metastasis collected were lymph node (n = 58), liver (n = 40), lung (n = 37), bone (n = 24), and brain (n = 8). Most patients (80.7%) were RMH good risk. Most patients (n = 62) had received 2+ prior lines of systemic treatment before receiving IO on trial; 27 patients (30.0%) received prior ICB. Liver metastases were associated with significantly shorter OS (HR: 0.38, CI: 0.17–0.84, p = 0.017). Patients with liver metastasis also trended towards having shorter PFS (HR: 0.70, CI: 0.41–1.19, p = 0.188). The median OS was substantially longer for patients without liver metastases (21.9 vs. 8.1 months, p = 0.0048).

Conclusions

Liver metastases may be a poor prognostic factor in patients receiving IO on phase 1 clinical trials. The presence of liver metastases may warrant consideration in updated prognostic models if these findings are validated in a larger prospective cohort.

Immune-related adverse events associated with programmed cell death protein-1 and programmed cell death ligand 1 inhibitors for non-small cell lung cancer: a PRISMA systematic review and meta-analysis

Background

Programmed cell death protein-1 (PD-1) and programmed cell death ligand 1 (PD-L1) inhibitors have remarkable clinical efficacy in the treatment of non-small cell lung cancer (NSCLC); however, the breakdown of immune escape causes a variety of immune-related adverse events (irAEs). With the increasing use of PD-1/PD-L1 inhibitors alone or in combination with other therapies, awareness and management of irAEs have become more important. We aimed to assess the incidence and nature of irAEs associated with PD-1 and PD-L1 inhibitors for NSCLC.

Methods

Articles from the MEDLINE, EMBASE, and Cochrane databases were searched through December 2017. The incidence of overall and organ-specific irAEs was investigated in all clinical trials with nivolumab, pembrolizumab, atezolimumab, durvalumab, and avelumab as single agents for treatment of NSCLC. We calculated the pooled incidence using R software with package Meta.

Results

Sixteen trials were included in the meta-analysis: 10 trials with PD-1 inhibitors (3734 patients) and 6 trials with PD-L1 inhibitors (2474 patients). The overall incidence of irAEs was 22% (95% confidence interval [CI], 17–28) for all grades and 4% (95% CI, 2–6) for high-grade irAEs. The frequency of irAEs varied based on drug type and organ, and patients treated with PD-1 inhibitors had an increased rate of any grade and high-grade irAEs compared with patients who received PD-L1 inhibitors. Organ-specific irAEs were most frequently observed in, in decreasing order, the endocrine system, skin, pulmonary tract, and gastrointestinal tract. The total number of patients whose death was attributed to irAEs was 14 (0.34%), and most (79%) of these patients died because of pneumonitis. The median time to the onset of irAEs after the initiation of treatment was 10 weeks (interquartile range, 6–19.5 weeks) and varied depending on the organ system involved.

Conclusions

The specificity of irAEs was closely associated with the mechanism of PD-1/PD-L1 antibodies involved in restarting anticancer immune attacks. Comprehensive understanding, timely detection, and effective management could improve the compliance of patients and guide the interruption of treatment.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5701-6) contains supplementary material, which is available to authorized users.

Combining Radiotherapy and Immunotherapy in Lung Cancer: Can We Expect Limitations Due to Altered Normal Tissue Toxicity?

In recent decades, technical advances in surgery and radiotherapy, as well as breakthroughs in the knowledge on cancer biology, have helped to substantially improve the standard of cancer care with respect to overall response rates, progression-free survival, and the quality of life of cancer patients. In this context, immunotherapy is thought to have revolutionized the standard of care for cancer patients in the long term. For example, immunotherapy approaches such as immune checkpoint blockade are currently increasingly being used in cancer treatment, either alone or in combination with chemotherapy or radiotherapy, and there is hope from the first clinical trials that the appropriate integration of immunotherapy into standard care will raise the success rates of cancer therapy to a new level. Nevertheless, successful cancer therapy remains a major challenge, particularly in tumors with either pronounced resistance to chemotherapy and radiation treatment, a high risk of normal tissue complications, or both, as in lung cancer. Chemotherapy, radiotherapy and immunotherapy have the capacity to evoke adverse effects in normal tissues when administered alone. However, therapy concepts are usually highly complex, and it is still not clear if combining immunotherapy with radio(chemo)therapy will increase the risk of normal tissue complications, in particular since normal tissue toxicity induced by chemotherapy and radiotherapy can involve immunologic processes. Unfortunately, no reliable biomarkers are available so far that are suited to predict the unique normal tissue sensitivity of a given patient to a given treatment. Consequently, clinical trials combining radiotherapy and immunotherapy are attracting major attention, not only regarding efficacy, but also with regard to safety. In the present review, we summarize the current knowledge of radiation-induced and immunotherapy-induced effects in tumor and normal tissue of the lung, and discuss the potential limitations of combined radio-immunotherapy in lung cancer with a focus on the suspected risk for enhanced acute and chronic normal tissue toxicity.