VEGFR2 and CD34 expression associated with longer survival in patients with pleural mesothelioma in the IFCT-GFPC-0701 MAPS phase 3 trial.

OBJECTIVES: VEGF/VEGFR autocrine loop is a hallmark of pleural mesothelioma (PM). We thus assayed the prognostic and predictive values of VEGFR-2 [vascular endothelial growth factor receptor 2 or Flk-1] and CD34, a marker of endothelial cells, in samples from patients accrued in the Mesothelioma Avastin Cisplatin Pemetrexed Study ('MAPS', NCT00651456). MATERIALS AND METHODS: VEGFR2 and CD34 expression were assayed using immunohistochemistry in 333 MAPS patients (74.3%), and their prognostic value was evaluated in terms of overall survival (OS) and progression-free survival (PFS) in univariate and multivariate analyses, before validation by bootstrap methodology. RESULTS: Positive VEGFR2 or CD34 staining was observed in 234/333 (70.2%) and 322/323 (99.6%) of tested specimens, respectively. VEGFR2 and CD34 staining correlated weakly, yet significantly, with each other (r = 0.36, p < 0.001). High VEGFR2 expression or high CD34 levels were associated with longer OS in PM patients in multivariate analysis (VEGFR2: adjusted [adj.] hazard ratio [HR]: 0.91, 95% confidence interval [CI] [0.88; 0.95], p < 0.001; CD34: adj. HR: 0.86, 95 %CI [0.76; 0.96], p = 0.010), with only high VEGFR2 expression resulting in significantly longer PFS (VEGFR2: adj. HR: 0.96, 95 %CI [0.92; 0.996], p = 0.032). Stability of these results was confirmed using bootstrap procedure. Nevertheless, VEGFR2 expression failed to specifically predict longer survival in bevacizumab-chemotherapy combination trial arm, regardless of whether the VEGFR2 score was combined or not with serum VEGF concentrations. CONCLUSION: VEGFR2 overexpression independently correlated with longer OS or PFS in PM patients, such biomarker deserving prospective evaluation as stratification variable in future clinical trials.

Brief Report: Severe Sotorasib-Related Hepatotoxicity and Non-Liver Adverse Events Associated With Sequential Anti-Programmed Cell Death (Ligand)1 and Sotorasib Therapy in KRASG12C-Mutant Lung Cancer.

INTRODUCTION: Sequential anti-programmed cell death protein 1 (PD-1) or anti-programmed death-ligand 1 (PD-L1) followed by small targeted therapy use is associated with increased prevalence of adverse events (AEs) in NSCLC. KRASG12C inhibitor sotorasib may trigger severe immune-mediated hepatotoxicity when used in sequence or in combination with anti-PD-(L)1. This study was designed to address whether sequential anti-PD-(L)1 and sotorasib therapy increases the risk of hepatotoxicity and other AEs. METHODS: This is a multicenter, retrospective study of consecutive advanced KRASG12C-mutant NSCLC treated with sotorasib outside clinical trials in 16 French medical centers. Patient records were reviewed to identify sotorasib-related AEs (National Cancer Institute Common Classification Criteria for Adverse Events-Version 5.0). Grade 3 and higher AE was considered as severe. Sequence group was defined as patients who received an anti-PD-(L)1 as last line of treatment before sotorasib initiation and control group as patients who did not receive an anti-PD-(L)1 as last line of treatment before sotorasib initiation. RESULTS: We identified 102 patients who received sotorasib, including 48 (47%) in the sequence group and 54 (53%) in the control group. Patients in the control group received an anti-PD-(L)1 followed by at least one treatment regimen before sotorasib in 87% of the cases or did not receive an anti-PD-(L)1 at any time before sotorasib in 13% of the cases. Severe sotorasib-related AEs were significantly more frequent in the sequence group compared with those in the control group (50% versus 13%, p < 0.001). Severe sotorasib-related AEs occurred in 24 patients (24 of 48, 50%) in the sequence group, and among them 16 (67%) experienced a severe sotorasib-related hepatotoxicity. Severe sotorasib-related hepatotoxicity was threefold more frequent in the sequence group compared with that in the control group (33% versus 11%, p = 0.006). No fatal sotorasib-related hepatotoxicity was reported. Non-liver severe sotorasib-related AEs were significantly more frequent in the sequence group (27% versus 4%, p < 0.001). Severe sotorasib-related AEs typically occurred in patients who received last anti-PD-(L)1 infusion within 30 days before sotorasib initiation. CONCLUSIONS: Sequential anti-PD-(L)1 and sotorasib therapy are associated with a significantly increased risk of severe sotorasib-related hepatotoxicity and severe non-liver AEs. We suggest avoiding starting sotorasib within 30 days from the last anti-PD-(L)1 infusion.

Histomolecular Resistance Mechanisms to First-Line Osimertinib in EGFR-Mutated Advanced Non-Small Cell Lung Cancer: A Multicentric Retrospective French Study.

BACKGROUND: Osimertinib is an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) used in first line for the treatment of advanced EGFR-mutated non-small cell lung cancer (NSCLC). OBJECTIVE: The identification of related histomolecular resistance mechanisms to first-line osimertinib is a critical step to define the optimal treatment strategy beyond progression. PATIENTS AND METHODS: All consecutive patients treated in the first line with osimertinib for advanced EGFR-mutated NSCLC at 10 hospitals in the Greater Paris area between April 2015 and January 2021 were included. Histomolecular data from plasma and tissue samples taken at progression under osimertinib were collected, and all samples were analyzed using DNA next-generation sequencing. Data on objective response rate (ORR), overall survival (OS), progression-free survival (PFS), and time to treatment discontinuation (TTD) were also collected. RESULTS: Overall, 104 patients were included. Most patients had adenocarcinoma (n = 102, 98%) with an exon 19 EGFR deletion (n = 54, 52%). Forty-two patients (50%) had central nervous system (CNS) metastasis at the time of osimertinib initiation. ORR was 76%, median PFS and OS were 12.6 months and 52 months, respectively, and TTD was 33 months. At the time of analysis, 44 patients (42%) had tumor progression, and among these patients, 27 (61%) contributive samples were available. The most frequent molecular alterations at progression were mesenchymal epithelial transition factor (MET) amplification (15%; n = 4) and EGFR C797S mutation (11%; n = 3). Histological transformation was found in one patient (4%). RNA next-generation sequencing was performed in eight patients and showed a CCDC6-RET fusion in one patient (12%). CONCLUSIONS: We confirmed the efficacy of osimertinib in patients with advanced EGFR mutation-positive NSCLC. At progression, the most frequent histomolecular alterations were MET amplification and EGFR C797S mutation.

Grade 3-4 Immune-Related Adverse Events Induced by Immune Checkpoint Inhibitors in Non-Small-Cell Lung Cancer (NSCLC) Patients Are Correlated with Better Outcome: A Real-Life Observational Study.

Background: Immune checkpoint inhibitors (ICIs) have been a major advance in treating non-small-cell lung cancer (NSCLC). Programmed cell death protein-1/programmed death-ligand 1 blockade enhances immune function, mediating anti-tumor activity, yet causing immune-related adverse events (irAEs). We investigated the prognostic role of Grade 3−4 irAEs on overall survival (OS). Methods: This observational study recruited advanced NSCLC patients who received ICIs at Bichat-Claude Bernard University Hospital and in a community hospital, Saint-Joseph Foundation (Paris), between 1 January 2016 and 31 December 2019. Immunotherapy as a single-agent or double-drug combination was applied in the first and later lines. Univariable and multivariable analyses were instrumental in evaluating the prognostic impact of irAEs. Results: Overall, 201 consecutive ICI-treated patients were enrolled. High-grade irAEs (Grades 3−4) occurred in 36 patients (17.9%), including 11 (30.5%) cases of pneumonitis, 8 (22.2%) of colitis, 4 (11.1%) hepatic, 3 (8.3%) dermatological, 2 (5.5%) neurological events, and 2 cases (5.5%) of poly-arthralgia. The median OS was 10.4 ± 1.36 months (95% CI:7.7−13.1), being significantly higher in patients with high-grade irAEs than those without, 27.8 months vs. 8.1 months, respectively (HR = 2.5; p < 0.0001). Multivariable analysis revealed an independent association between high-grade irAEs and longer OS (HR = 0.29, 95% CI: 0.2−0.6, p < 0.0001). Conclusions: Our real-life study confirms that high-grade irAEs predict longer OS in advanced NSCLC.

Measuring Walking Speed Failed to Predict Early Death and Toxicity in Elderly Patients with Metastatic Non-Small-Cell Lung Cancer (NSCLC) Selected for Undergoing First-Line Systemic Treatment: An Observational Exploratory Study.

Walking speed (WS) has emerged as a potential predictor of mortality in elderly cancer patients, yet data involving non-small-cell lung cancer (NSCLC) patients are scarce. Our prospective exploratory study sought to determine whether WS would predict early death or toxicity in patients with advanced NSCLC receiving first-line systemic intravenous treatment. Overall, 145 patients of ≥70 years were diagnosed with NSCLC over 19 months, 91 of whom displayed locally-advanced or metastatic cancer. As first-line treatment, 21 (23%) patients received best supportive care, 13 (14%) targeted therapy, and 57 (63%) chemotherapy or immunotherapy. Among the latter, 38 consented to participate in the study (median age: 75 years). Median cumulative illness rating scale for geriatrics (CIRS-G) was 10 (IQR: 8−12), and median WS 1.09 (IQR: 0.9−1.31) m/s. Older age (p = 0.03) and comorbidities (p = 0.02) were associated with Grade 3−4 treatment-related adverse events or death within 6 months of accrual. Overall survival was 14.3 (IQR: 6.1-NR) months for patients with WS < 1 m/s versus 17.3 (IQR: 9.2−26.5) for those with WS ≥ 1 m/s (p = 0.78). This exploratory study revealed WS to be numerically, yet not significantly, associated with early mortality in older metastatic NSCLC patients. Following these hypothesis-generating results, a larger prospective, multicenter study appears to be required to further investigate this outcome.

A defect of amphiregulin release predicted longer survival independently of YAP expression in patients with pleural mesothelioma in the IFCT-0701 MAPS phase 3 trial.

The Hippo pathway effector YAP is dysregulated in malignant pleural mesothelioma (MPM). YAP's target genes include the secreted growth factor amphiregulin (AREG), which is overexpressed in a wide range of epithelial cancers and plays an elusive role in MPM. We assayed the expression of YAP and AREG in MPM pathology samples and that of AREG additionally in plasma samples of patients from the randomized phase 3 IFCT-0701 Mesothelioma Avastin Cisplatin Pemetrexed Study (MAPS) using immunohistochemistry and ELISA assays, respectively. MPM patients frequently presented high levels of tumor AREG (64.3%), a high cytosolic AREG expression being predictive of a better prognosis with longer median overall and progression-free survival. Surprisingly, tumor AREG cytosolic expression was not correlated with secreted plasma AREG. By investigating the AREG metabolism and function in MPM cell lines H2452, H2052, MSTO-211H and H28, in comparison with the T47D ER+ breast cancer cell line used as a positive control, we confirm that AREG is important for cell invasion, growth without anchorage, proliferation and apoptosis in mesothelioma cells. Yet, most of these MPM cell lines failed to correctly execute AREG posttranslational processing by metalloprotease ADAM17/tumor necrosis factor-alpha-converting enzyme (TACE) and extracell secretion. The favorable prognostic value of high cytosolic AREG expression in MPM patients could therefore be sustained by default AREG posttranslational processing and release. Thus, the determination of mesothelioma cell AREG content could be further investigated as a prognostic marker for MPM patients and used as a stratification factor in future clinical trials.

Transthoracic lung biopsy for pulmonary nodules ≤20†mm in routine clinical care.

BACKGROUND: Computed tomography (CT) screening has improved lung cancer survival, yet increasingly detects small lung lesions. Thus, the number of transthoracic lung biopsies (TTLB) for small nodules is expected to rise significantly. The aim of the present study was to evaluate the diagnostic accuracy and safety of CT-guided TTLB for nodules ≤20 mm versus nodules >20 mm. STUDY DESIGN AND METHODS: Data for CT-guided TTLBs from 474 consecutive patients were prospectively collected over a 3-year period (198 lesions ≤20 mm and 276 lesions >20 mm) in a teaching hospital and analysed in terms of diagnostic performance and complications. RESULTS: There were more conclusive biopsies in the >20 mm lesion group (n=236, 85.5%) than in ≤20 mm lesion group (n=140, 70.7%; p<0.001). The overall accuracy, sensitivity, specificity and negative predictive value for diagnosing malignant lesions after first TTLB were 88.4%, 84%, 100% and 70.1%, respectively, for ≤20 mm lesions, and 94.2%, 93%, 100% and 74.6%, respectively, for >20 mm lesions. Pneumothorax requiring drainage was significantly more common for ≤20 mm lesions, compared to TTLB of larger lesions (9.6% versus 4.3%; p=0.02). Prolonged hospital stay due to pneumothorax occurred in 27 (17.4%) TTLBs of ≤20 mm lesions and 15 (7%) TTLBs of >20 mm lesions (p=0.002). There were no deaths. The only variable significantly associated with diagnostic failure in the ≤20 mm lesion group was the radiologist's experience. INTERPRETATION: TTLBs for lesions ≤20 mm were associated with slightly lower diagnostic performance, whereas the higher rate of major complications was still inferior to that extrapolated from United States insurance databases.

Third dose of anti-SARS-CoV-2 vaccine for patients with cancer: Should humoral responses be monitored? A position article.

Taking into account higher risk of severe coronavirus disease 2019 or death among patients with cancer, as well as impaired immunogenicity after anti-SARS-CoV-2 vaccines, in addition to waning immunity, booster dosing appears mandatory in this patient population. This review sought to provide reasonable evidence so as to assist oncologists in their daily practice, helping them decide when an anti-SARS-Cov2 antibody (Ab) dosage should be scheduled after a full two-dose vaccination and, if necessary, propose an early third dose (D3). Such D3 could apply to non-responder patients with anti-Spike (S) Abs titres <40 binding Ab unit (BAU)/mL. For lowresponder patients with anti-S Ab titres between 40 BAU/mL and 100/260 BAU/mL (suggested area of uncertainty), an early D3 may similarly be proposed. Nevertheless, this D3 could be administered in a less urgent manner, taking into account associated comorbidities and regional epidemic incidence rates. This latter strategy may comprise a monthly dosage of anti-S titres so as to better assess the kinetics of waning immunity. For responder patients with anti-S titres above 260 BAU/mL, we suggest to follow the recommendations outlined for the general population. Given this context, patients with anti-S titres above 1000 BAU/mL should be given the possibility to undergo anti-S titre control after three months, designed to assess rapid humoral waning immunity. We strongly recommend that patients with cancer be included into observational serological monitoring studies or clinical trials that are dedicated to severe immunocompromised patients without any humoral seroconversion after D3.

Efficacy of Severe Acute Respiratory Syndrome Coronavirus-2 Vaccine in Patients With Thoracic Cancer: A Prospective Study Supporting a Third Dose in Patients With Minimal Serologic Response After Two Vaccine Doses.

INTRODUCTION: Coronavirus disease 2019 resulted in a 30% mortality rate in patients with thoracic cancer. Given that patients with cancer were excluded from serum antisevere acute respiratory syndrome coronavirus-2 (SARS-CoV-2) vaccine registration trials, it is still unknown whether they would develop a protective antispike antibody response after vaccination. This prospective vaccine monitoring study primarily aimed to assess humoral responses to the SARS-CoV-2 vaccine in patients with thoracic cancer. METHODS: SARS-CoV-2-spike antibodies were measured using the Abbot Architect SARS-CoV-2 immunoglobulin G immunoassay before the first injection of BNT162b2 mRNA vaccine, at week 4, and 2 to 16 weeks after the second vaccine dose administration. The factors associated with antibody response were analyzed. RESULTS: Overall, 306 patients, with a median age of 67.0 years (interquartile range: 58-74), were vaccinated. Of these, 283 patients received two vaccine doses at 28-day intervals. After a 6.7-month median follow-up, eight patients (2.6%) contracted proven symptomatic SARS-CoV-2 infection, with rapid favorable evolution. Of the 269 serologic results available beyond day 14 after the second vaccine dose administration, 17 patients (6.3%) were still negative (<50 arbitrary units/mL, whereas 34 (11%) were less than 300 arbitrary units/mL (12.5th percentile). In multivariate analysis, only age (p < 0.01) and long-term corticosteroid treatment (p = 0.01) were significantly associated with a lack of immunization. A total of 30 patients received a third vaccine dose, with only three patients showing persistently negative serology thereafter, whereas the others exhibited clear seroconversion. CONCLUSIONS: SARS-CoV2 vaccines were found to be efficient in patients with thoracic cancer, most of them being immunized after two doses. A third shot given to 1% of patients with persistent low antibody titers resulted in an 88% immunization rate.

Immunotherapy, the promise for present and future of malignant pleural mesothelioma (MPM) treatment.

Due to occupational asbestosis exposure, the incidence of malignant pleural mesothelioma (MPM) has continuously increased over the last 30 years, with a plateau anticipated around the year 2030 in Western countries. Molecular MPM carcinogenesis involves alterations of NF2, RASSF1, LATS2WT1, p16, as well as BAP-1tumor-suppressor genes, which usually regulate apoptosis, cell invasion, motility, cell division, chromatin remodeling, as well as control of DNA repair. In few selected patients, debulking surgery consisting of pleurectomy-decortication is carried out, resulting in unsatisfactory long-term results. For about 15 years, first-line chemotherapy has been primarily based on a doublet of pemetrexed and cisplatin. Adding the monoclonal antibody bevacizumab (Avastin®), which targets vascular endothelial growth factor (VEGF), has been shown to improve overall survival (OS) by nearly 19 months. The emergence of immune check-point inhibitors (ICIs) in MPM treatment has recently been associated with substantial survival improvements in both second- and first-line settings. Similarly to non-small-cell lung cancer (NSCLC) patients, on-going trials are presently exploring the chemotherapy-ICI combination in MPM management, and depending on their results, this combination could represent a further major advance in this previously orphan disease. The current article reviews recent clinical trial results, as well as future clinical developments in this moving field.

NKX2.1 (TTF1) germline mutation associated with pulmonary fibrosis and lung cancer.

Germline surfactant-associated genes mutations are associated with ILD and increased risk of lung cancer https://bit.ly/3CkkXgD.

Poor performance status patient with long-lasting major response to pembrolizumab in advanced non-small-cell lung cancer with coexisting POLE mutation and deficient mismatch repair pathway.

Immunotherapy with immune checkpoint inhibitors (ICIs) represents a major breakthrough in lung cancer treatment. For patients with advanced non-small-cell lung cancer (NSCLC) and poor performance status (PS), the availability of sensitivity markers to immune-checkpoint inhibitors (ICI) would be useful for attending physicians and assist them in their decision-making process. Deficient mismatch repair (dMMR) can lead to high microsatellite instability (MSI-H) and coexist with mutations in polymerase proofreading (DNA polymerase Epsilon POLE and delta 1 POLD1) with a specific mutational signature. This would result in high tumor mutational burden and programmed cell death protein ligand 1 (PD-L1) overexpression. We report herein on a NSCLC case with MSI-H and POLE mutation in a patient with inaugural poor general condition, who exhibited prolonged response to anti-programmed cell death protein (PD-1) therapy. Additionally, there was a marked improvement of the patient's performance status, from PS 3 before ICI administration to PS 1 upon ICI therapy.

Clinicopathologic Features and Response to Therapy of NRG1 Fusion-Driven Lung Cancers: The eNRGy1 Global Multicenter Registry.

PURPOSE: Although NRG1 fusions are oncogenic drivers across multiple tumor types including lung cancers, these are difficult to study because of their rarity. The global eNRGy1 registry was thus established to characterize NRG1 fusion-positive lung cancers in the largest and most diverse series to date. METHODS: From June 2018 to February 2020, a consortium of 22 centers from nine countries in Europe, Asia, and the United States contributed data from patients with pathologically confirmed NRG1 fusion-positive lung cancers. Profiling included DNA-based and/or RNA-based next-generation sequencing and fluorescence in situ hybridization. Anonymized clinical, pathologic, molecular, and response (RECIST v1.1) data were centrally curated and analyzed. RESULTS: Although the typified never smoking (57%), mucinous adenocarcinoma (57%), and nonmetastatic (71%) phenotype predominated in 110 patients with NRG1 fusion-positive lung cancer, further diversity, including in smoking history (43%) and histology (43% nonmucinous and 6% nonadenocarcinoma), was elucidated. RNA-based testing identified most fusions (74%). Molecularly, six (of 18) novel 5' partners, 20 unique epidermal growth factor domain-inclusive chimeric events, and heterogeneous 5'/3' breakpoints were found. Platinum-doublet and taxane-based (post-platinum-doublet) chemotherapy achieved low objective response rates (ORRs 13% and 14%, respectively) and modest progression-free survival medians (PFS 5.8 and 4.0 months, respectively). Consistent with a low programmed death ligand-1 expressing (28%) and low tumor mutational burden (median: 0.9 mutations/megabase) immunophenotype, the activity of chemoimmunotherapy and single-agent immunotherapy was poor (ORR 0%/PFS 3.3 months and ORR 20%/PFS 3.6 months, respectively). Afatinib achieved an ORR of 25%, not contingent on fusion type, and a 2.8-month median PFS. CONCLUSION: NRG1 fusion-positive lung cancers were molecularly, pathologically, and clinically more heterogeneous than previously recognized. The activity of cytotoxic, immune, and targeted therapies was disappointing. Further research examining NRG1-rearranged tumor biology is needed to develop new therapeutic strategies.

A new KIF5B-ERBB4 gene fusion in a lung adenocarcinoma patient.

ERBB4 fusion is a rare, novel oncogenic event involved in the development of lung adenocarcinoma that is not routinely looked for, although ERBB4 fusion is a potential target for existing pan-ErbB tyrosine kinase and must be implemented in the laboratory https://bit.ly/3nYmGQ9.

Does Very Poor Performance Status Systematically Preclude Single Agent Anti-PD-1 Immunotherapy? A Multicenter Study of 35 Consecutive Patients.

Anti-PD-1 antibodies prolong survival of performance status (PS) 0-1 advanced non-small-cell lung cancer (aNSCLC) patients. Their efficacy in PS 3-4 patients is unknown. Conse- cutive PS 3-4 aNSCLC patients receiving compassionate nivolumab were accrued by 12 French thoracic oncology departments, over 24 months. Overall survival (OS) was calculated using the Kaplan-Meier method. Prognostic variables were assessed using Cox proportional hazards models. Overall, 35 PS 3-4 aNSCLC patients (median age 65 years) received a median of 4 nivolumab infusions (interquartile range [IQR], 1-7) as first- (n = 6) or second-line (n = 29) therapy. At a median of 52-month follow-up (95%CI, 41-63), 32 (91%) patients had died. Median progression-free survival was 2.1 months (95%CI, 1.1-3.2). Median OS was 4.4 months (95%CI, 0.5-8.2). Overall, 20% of patients were alive at 1 year, and 14% at 2 years. Treatment-related adverse events occurred in 8/35 patients (23%), mostly of low-grade. After adjustment, brain metastases (HR = 5.2; 95%CI, 9-14.3, p = 0.001) and <20 pack-years (HR = 4.8; 95%CI, 1.7-13.8, p = 0.003) predicted worse survival. PS improvement from 3-4 to 0-1 (n = 9) led to a median 43-month (95%CI, 0-102) OS. Certain patients with very poor general condition could derive long-term benefit from nivolumab salvage therapy.

Intergroupe francophone de cancérologie thoracique, Société de pneumologie de langue française, and Société d'imagerie thoracique statement paper on lung cancer screening.

Following the American National Lung Screening Trial results in 2011 a consortium of French experts met to edit a statement. Recent results of other randomized trials gave the opportunity for our group to meet again in order to edit updated guidelines. After literature review, we provide here a new update on lung cancer screening in France. Notably, in accordance with all international guidelines, the experts renew their recommendation in favor of individual screening for lung cancer in France as per the conditions laid out in this document. In addition, the experts recommend the very rapid organization and funding of prospective studies, which, if conclusive, will enable the deployment of lung cancer screening organized at the national level.

Treatment strategies and safety of rechallenge in the setting of immune checkpoint inhibitors-related myositis: a national multicentre study.

OBJECTIVES: The occurrence of immune-related myositis (irM) is increasing, yet there are no therapeutic guidelines. We sought to analyse the current therapeutic strategies of irM and evaluate the outcomes of immune checkpoint inhibitors (ICIs) rechallenge. METHODS: We conducted a nationwide retrospective study between April 2018 and March 2020 including irM without myocardial involvement. Depending on the presence of cutaneous signs or unusual histopathological features, patients were classified into two groups: typical or atypical irM. Therapeutic strategies were analysed in both groups. The modalities and outcomes of ICI rechallenge were reviewed. RESULTS: Among the 20 patients, 16 presented typical irM. Regardless of severity, most typical irM were treated with steroid monotherapy (n = 14/16) and all had a complete response within ≤3 weeks. The efficacy of oral steroids for non-severe typical irM (n = 10) was the same with low-dose (≤0.5 mg/kg/day) or high-dose (1 mg/kg/day). Severe typical irM were successfully treated with intravenous methylprednisolone. Atypical irM (n = 4) had a less favourable evolution, including one irM-related death, and required heavy immunosuppression. ICIs were safely reintroduced in nine patients presenting a moderate (n = 6) or a severe (n = 3) irM. CONCLUSION: Our data highlight that steroid monotherapy is an effective treatment for typical irM, either with prednisone or with intravenous methylprednisone pulses depending on the severity. The identification of unusual features is important in determining the initial therapeutic strategy. The outcomes of rechallenged patients are in favour of a safe reintroduction of ICI following symptom resolution and creatin kinase (CK) normalization in moderate and severe forms of irM.

Biomarkers of Response to Etoposide-Platinum Chemotherapy in Patients with Grade 3 Neuroendocrine Neoplasms.

Etoposide-platinum (EP) chemotherapy has long been the reference treatment for grade 3 neuroendocrine neoplasms (G3 NEN). However, G3 NEN are heterogeneous, including well-differentiated tumors (NET) and poorly differentiated large (LCNEC) or small (SCNEC) cell carcinomas, whose response to EP chemotherapy varies considerably. Our aim was to evaluate predictive biomarkers for the response to EP chemotherapy in G3 NEN. We retrospectively studied 89 patients with lung (42%) and digestive (58%) G3 NEN treated by EP chemotherapy between 2006 and 2020. All cases were centrally reviewed for cytomorphology/Ki-67 and immunohistochemistry of retinoblastoma protein (Rb)/p53/p16, analyzed using a semi-quantitative score. The absence of Rb staining (Rbinap) or the absence of very intense p53 staining (p53inap) were considered inappropriate. Rb staining was also studied as a quantitative marker, the best threshold being determined by ROC curve. Intense p16 staining (p16high) also suggested cell cycle dysregulation. Our primary endpoint was the objective response rate (ORR). We included 10 G3 NET, 31 LCNEC and 48 SCNEC, which showed ORR of 20%, 32% and 75%, respectively (NET vs. NEC, p = 0.040; LCNEC vs. SCNEC, p < 0.001). The ORR was significantly higher in NEN presenting with Rbinap (63% vs. 42%, p = 0.025) and p16high (66% vs. 35%, p = 0.006). Rb < 150 optimally identified responders (AUC = 0.657, p < 0.001). The ORR was 67% in Rb < 150 (vs. 25%, p = 0.005). On multivariate analysis, only Rb < 150 was independently associated with ORR (OR 4.16, 95% CI 1.11-15.53, p = 0.034). We confirm the heterogeneity of the response to EP treatment in G3 NEN. Rb < 150 was the best predictive biomarker for the response to EP, and p53 immunostaining had no additional value.