Early Circulating Tumour DNA Variations Predict Tumour Response in Melanoma Patients Treated with Immunotherapy.

Antibodies targeting immune checkpoints were recently approved for metastatic melanoma. However, not all patients will respond to the treatment and some will experience grade III-IV immune-related adverse events. Therefore, early identification of non-responder patients would greatly aid clinical practice. Detection of circulating tumour DNA (ctDNA) is a non-invasive approach to monitor tumour response. Digital droplet PCR was used to quantify BRAF and NRAS mutations in the plasma of patients with metastatic melanoma treated with immunotherapy. In 16 patients, ctDNA variations mirrored tumour response (p = 0.034) and ctDNA augmentation during follow-up detected tumour progression with 100% specificity. In 13 patients, early ctDNA variation was associated with clinician decision at first evaluation (p = 0.0046), and early ctDNA increase with shorter progression-free survival (median 21 vs. 145 days; p = 0.001). Monitoring ctDNA variations early during immunotherapy may help clinicians rapidly to discriminate non-responder patients, allow early adaptation of therapeutic strategies, and reduce exposure to ineffective, expensive treatment.

Immune-checkpoint inhibitors associated with interstitial lung disease in cancer patients.

Immunotherapy is becoming a standard of care for many cancers. Immune-checkpoint inhibitors (ICI) can generate immune-related adverse events. Interstitial lung disease (ILD) has been identified as a rare but potentially severe event.Between December 2015 and April 2016, we conducted a retrospective study in centres experienced in ICI use. We report the main features of ICI-ILD with a focus on clinical presentation, radiological patterns and therapeutic strategies.We identified 64 (3.5%) out of 1826 cancer patients with ICI-ILD. Patients mainly received programmed cell death-1 inhibitors. ILD usually occurred in males, and former or current smokers, with a median age of 59 years. We observed 65.6% grade 2/3 severity, 9.4% grade 4 severity and 9.4% fatal ILD. The median (range) time from initiation of immunotherapy to ILD was 2.3 (0.2-27.4) months. Onset tended to occur earlier in lung cancer versus melanoma: median 2.1 and 5.2 months, respectively (p=0.02). Ground-glass opacities (81.3%) were the predominant lesions, followed by consolidations (53.1%). Organising pneumonia (23.4%) and hypersensitivity pneumonitis (15.6%) were the most common patterns. Overall survival at 6 months was 58.1% (95% CI 37.7-73.8%).ICI-ILD often occurs early and displays suggestive radiological features. As there is no clearly identified risk factor, oncologists need to diagnose and adequately treat this adverse event.

ICU admission for solid cancer patients treated with immune checkpoint inhibitors.

BACKGROUND: Immune checkpoint inhibitors (ICI) have revolutionized the management of cancer. They can induce immune-related adverse events (irAE) leading to intensive care unit (ICU) admission. We aimed to describe irAEs for ICU admissions in solid cancer patients treated with ICIs. METHODS: This prospective multicenter study was conducted in France and Belgium. Adult patients with solid tumor and treated with systemic ICIs within the last 6 months, requiring non-programmed ICU admission were included. Patients admitted for microbiologically documented sepsis were excluded. Imputability of irAEs in ICU admissions was described according to the WHO-UMC classification system at ICU admission and at ICU discharge. The use of immunosuppressant treatment was reported. RESULTS: 115 patients were eligible. Solid tumor was mainly lung cancer (n = 76, 66%) and melanoma (n = 18, 16%). They were mainly treated with an anti-PD-(L)1 alone (n = 110, 96%). Main ICU admission reasons were acute respiratory failure (n = 66, 57%), colitis (n = 14, 13%), and cardiovascular disease (n = 13, 11%). ICU admission was considered "likely" associated with irAE for 48% (n = 55) of patients. Factors independently associated with irAE were a good ECOG performance status (PS) (ECOG-PS of 0 or 1 vs. ECOG-PS of 2-3, odds ratio [OR] = 6.34, 95% confidence interval [95% CI] 2.13-18.90, and OR = 3.66, 95% CI 1.33-10.03, respectively), and a history of irAE (OR = 3.28, 95% CI 1.19-9.01). Steroids were prescribed for 41/55 (75%) patients with ICU admission "likely" related to irAE. Three patients were subsequently treated with immunosuppressants. CONCLUSION: IrAEs accounted for half of ICU admissions in cancer patients receiving ICIs. They could be treated with steroids. Identifying the imputability of irAEs in ICU admissions remains a challenge.

Immune Checkpoint Inhibitors Rechallenge Efficacy in Non-Small-Cell Lung Cancer Patients.

BACKGROUND: Immune checkpoint inhibitor (ICPi) rechallenge could represent an attractive option in non-small-cell lung cancer (NSCLC), yet no sufficient data supporting this strategy are available. This retrospective observational multicenter national study explored the efficacy of anti-programmed cell death 1 (PD-1)/programmed death ligand 1 (PD-L1) rechallenge in advanced NSCLC patients, looking for potential clinical features associated with greater outcomes. PATIENTS AND METHODS: We retrospectively collected data from 144 advanced NSCLC patients whose disease was rechallenged with ICPis after ≥ 12 weeks of discontinuation. The progression-free survival (PFS) and overall survival (OS) were calculated from first or second ICPi initiation to disease progression (PFS1 and PFSR, respectively), death, or last follow-up (OS1, OSR), respectively. RESULTS: The median (interquartile range) age was 63 (58-70) years. Most patients were male (67%) and smokers (87%). Most had adenocarcinomas (62%) and/or stage IV disease at diagnosis (66%). The best response at rechallenge was not associated with that under the first ICPi (P = 1.10-1). The median (95% confidence interval) PFS1 and PFSR were 13 (10-16.5) and 4.4 (3-6.5) months, respectively. The median (95% confidence interval) OS1 and OSR were 3.3 (2.9-3.9) and 1.5 (1.0-2.1) years, respectively. Longer PFSR and OSR were found in patients discontinuing first ICPi because of toxicity or clinical decision, those not receiving systemic treatment between the two ICPis, and those with good Eastern Cooperative Oncology Group performance status at rechallenge. Only performance status proved to affect outcomes at multivariate analysis. CONCLUSION: Patients discontinuing first ICPi because of toxicity or clinical decision, those able to maintain a treatment-free period, and those with good performance status may be potential candidates for rechallenge.

Management of pulmonary toxicity associated with immune checkpoint inhibitors.

Immunotherapy has become a standard of care in oncology, following the recent approvals of cytotoxic T-lymphocyte-associated protein-4 and programmed cell death-1 inhibitors in lung cancer, melanoma, renal cell carcinoma, Hodgkin's lymphoma, bladder, head and neck cancers. Besides their efficacy, these agents also generate specific immune-related adverse events. Due to the increasing prescription of immune-checkpoint inhibitors, the incidence of immune toxicity will continue to rise. The awareness of immune-related adverse events is key to ensuring both diagnosis and management of the possible serious adverse events. Although severe immune-related adverse events remain rare, they can lead to discontinued treatment or to death if they are not forecasted and managed properly. Even if lung toxicity is not the most frequent adverse event, it remains critical as it can be life-threatening. Herein, the main aspects of pulmonary toxicity are reviewed and guidelines are also proposed in order to manage the possible side-effects.

Targeted sequencing of plasma cell-free DNA to predict response to PD1 inhibitors in advanced non-small cell lung cancer.

OBJECTIVES: Tumor mutational burden is an emerging biomarker of response to immune checkpoint inhibitors (ICI), whose clinical adoption is challenging. We hypothesized that targeting limited but relevant genetic alterations in plasma cell-free DNA along with early monitoring may non-invasively predict response to ICI in advanced non-small cell lung cancer (NSCLC). MATERIAL AND METHODS: Plasma samples from patients with progressive NSCLC collected before ICI initiation and at 1 month were profiled from responders (R: PFS > 6 months) and non-responders (NR: progressive disease at first evaluation) using amplicon sequencing of hotspots and coding regions from 36 genes. The molecular profile of ctDNA, and its early kinetics were analyzed. RESULTS: 97 patients were analyzed, of which 86 (39 R, 47 NR) were evaluable. Alterations in ctDNA were detectable in 67/86 baseline samples (78%). The detection of a targetable oncogenic driver was associated with a 2 months PFS. The presence of a PTEN or STK11 mutation was correlated with early progression (HR 8.9, p = 0.09 for PTEN, HR 4.7, p = 0.003 for STK11), while transversion mutations (Tv) in KRAS and TP53 predicted better outcomes (HR 0.36, p = 0.011 for TP53 Tv; HR 0.46, p = 0.11 for KRAS Tv). Patients with a low "immune score" (driver and/or PTEN or STK11 mutation and/or without KRAS or TP53 Tv) derived poor outcomes (median PFS 2 months), compared with patients with a high immune score (no driver, no PTEN or STK11 and with KRAS or TP53 Tv (median PFS 14 months, p = 0.0001, HR 2.96). Early changes in the ctDNA allele fraction (AF) of 65 specimens were correlated with clinical outcomes (14 months PFS if AF decreases vs. 2 months if AF increases, p < 0.0001). CONCLUSION: Targeted sequencing of plasma ctDNA and monitoring its early variations can predict response to ICI.

PD-L1 expression in circulating tumor cells of advanced non-small cell lung cancer patients treated with nivolumab.

BACKGROUND: Inhibitors of the PD-1/PD-L1 immune checkpoint have become a standard of care in non-small cell lung cancer (NSCLC). Patient selection, currently based on PD-L1 expression on tumor tissue, is limited by its temporal and spatial heterogeneity. We hypothesized that liquid biopsy with PD-L1 analysis on circulating tumor cells (CTCs) might overcome this limitation. METHODS: Blood samples were prospectively collected from patients with advanced NSCLC before nivolumab treatment and at the time of progression. CTCs were isolated using a cell size-based technology. PD-L1 expression was assessed by immunofluorescence on CTCs and immunohistochemistry on tissue biopsies. RESULTS: 113 specimens from 96 patients were collected. Baseline PD-L1 expression could be assessed on 72% and 93% of tissue and CTC, respectively. CTCs were more frequently found to be PD-L1 positive than tissue (83% vs. 41%) and no correlation was observed between tissue and CTC PD-L1 expression (r = 0.04, p = 0.77). Pre-treatment high CTC number was associated with increased risk of death and progression (HR1.06, p = 0.03 for OS; HR1.05, p = 0.02 for PFS). The presence of pre-treatment PD-L1+CTC was not significantly correlated with outcomes but a higher baseline PD-L1+ CTC number (≥1%) was observed in the "non-responders" group (PFS <6 months) (p = 0.04) and PD-L1+CTC were seen in all patients at progression. CONCLUSION: Assessment of PD-L1 expression in CTCs is feasible and CTCs are more often positive than in tissue. Pre-treatment PD-L1+CTCs are associated with bad prognosis in patients treated with PD-1 inhibitors.

Monitoring of KRAS-mutated ctDNA to discriminate pseudo-progression from true progression during anti-PD-1 treatment of lung adenocarcinoma.

OBJECTIVES: Pseudo-progression is a rare but worrying situation for both clinicians and patients during immunotherapy. Dedicated ir-RECIST criteria have been established to improve this situation. However, this can be sometimes considered inadequate and patients experiencing true progression may then receive inefficient treatments. Additional reliable tools to discriminate pseudo from true progression are thus needed. So far, no biomarker has been identified to distinguish pseudo from true progression. We hypothesize that biomarkers associated with the molecular characteristics of the tumor may be of interest. To avoid a tumor re-biopsy, circulating markers appear to be a less invasive and reproducible procedure. As ctDNA kinetics correlate with the response to treatment in KRAS-mutated adenocarcinoma, we anticipated that this analysis could be of interest. MATERIALS AND METHODS: We monitored the level of KRAS-mutated ctDNA by digital droplet PCR in serial plasma samples from two patients who had experienced pseudo-progression and compared the variations with those from of a patient that had true progression. RESULTS: ctDNA showed rapid and dramatic decreases in pseudo-progressive patients, whereas it was strongly increased in the progressive patient. CONCLUSIONS: ddPCR of ctDNA may thus be an additional tool to discriminate pseudo-progression from true progression for tumors that harbor an oncogenic addiction.

Targeting the immune system to treat lung cancer: rationale and clinical experience.

The use of immunotherapy that harnesses and enhances the innate powers of the immune system to fight cancer cells represents the most promising new cancer treatment approach since the development of the first chemotherapies and, more recently, targeted therapies. Unexpectedly, lung cancer has recently emerged as an exciting new target for immune-based therapies. Several approaches to immunotherapy for lung cancer have shown promise in early clinical trials and in late-phase development. The most advanced strategies can be split into two main categories: therapeutic vaccines and checkpoint inhibitors. At this time of great expectations, this review provides the reader with an update on the immunotherapies used to treat lung cancer with a focus on the rationale of targeting the immune system. It reports the results from recent major clinical trials, describes new toxicity profiles associated with such drugs, and particularly the role of the pulmonologists in their management. This review provides an overview of the main perspectives within this field.