Comparison of juvenile and adult myasthenia gravis in a French cohort with focus on thymic histology.

Myasthenia gravis (MG) is an autoimmune disease characterized by muscle fatigability due to acetylcholine receptor (AChR) autoantibodies. To better characterize juvenile MG (JMG), we analyzed 85 pre- and 132 post-pubescent JMG (with a cutoff age of 13) compared to 721 adult MG patients under 40 years old using a French database. Clinical data, anti-AChR antibody titers, thymectomy, and thymic histology were analyzed. The proportion of females was higher in each subgroup. No significant difference in the anti-AChR titers was observed. Interestingly, the proportion of AChR+ MG patients was notably lower among adult MG patients aged between 30 and 40 years, at 69.7%, compared to over 82.4% in the other subgroups. Thymic histological data were examined in patients who underwent thymectomy during the year of MG onset. Notably, in pre-JMG, the percentage of thymectomized patients was significantly lower (32.9% compared to more than 42.5% in other subgroups), and the delay to thymectomy was twice as long. We found a positive correlation between anti-AChR antibodies and germinal center grade across patient categories. Additionally, only females, particularly post-JMG patients, exhibited the highest rates of lymphofollicular hyperplasia (95% of cases) and germinal center grade. These findings reveal distinct patterns in JMG patients, particularly regarding thymic follicular hyperplasia, which appears to be exacerbated in females after puberty.

Real-world outcomes of lobectomy, segmentectomy, and wedge resection for the treatment of stage c-IA lung carcinoma.

OBJECTIVES: To determine safety and survival outcomes associated with lobectomy, segmentectomy, and wedge resection for early-stage lung cancer by quiring the French population-based registry EPITHOR. METHODS: Retrospective analysis of 19,452 patients with stage c IA lung carcinoma who underwent lobectomy, segmentectomy, or wedge resection between 2016 and 2022 with curative-intent. Main outcomes measures were 90-day mortality and 5-year overall survival estimates. Proportional hazards regression and propensity score matching were used to adjust outcomes for key patient, tumour, and practice environment factors. RESULTS: The treatment distribution was 72.2% for lobectomy, 21.5% for segmentectomy, and 6.3% for wedge. Unadjusted 90-day mortality rates were 1.6%, 1.2% and 1.1%, respectively (P = 0.10). Unadjusted 5-year overall survival estimates were 80%, 78% and 70%, with significant inter-group survival curves differences (P < 0.0001). Multivariable proportional hazards regression showed that wedge was associated with worse overall survival (adjusted hazard ratio [AHR], 1.23 [95% CI, 1.03-1.47]; P = 0.021) compared with lobectomy, while no significant difference was disclosed when comparing segmentectomy to lobectomy (1.08 [0.97-1.20]; P = 0.162). The three-way propensity score analyses confirmed similar 90-day mortality rate for wedge resection and segmentectomy compared with lobectomy (HR: 0.43; 95% CI: 0.16-1.11; P = 0.081 and 0.99; 0.48-2.10; P = 0.998, respectively), but poorer overall survival (1.45; 1.13-1.86; P = 0.003 and 1.31; 1-1.71; P = 0.048, respectively). CONCLUSIONS: Wedge resection was associated with comparable 90-day mortality but lower overall survival when compared to lobectomy. Overall, all types of sublobar resections may not offer equivalent oncologic effectiveness in real-world settings.

In silico evidence that substitution of glycine for valine (p.G8V) in a common variant of TMPRSS2 isoform 1 increases accessibility to an endocytic signal: Implication for SARS-cov-2 entry into host cells and susceptibility to COVID-19.

The TMPRSS2 protease plays a key role in the entry of the SARS-CoV-2 into cells. The TMPRSS2 gene is highly polymorphic in humans, and some polymorphisms may affect the susceptibility to COVID-19 or disease severity. rs75603675 (c.23G > T) is a missense variant that causes the replacement of glycine with valine at position 8 (p.G8V) in the TMPRSS2 isoform 1. According to GnomAD v4.0.0 database, the allele frequency of the rs75603675 on a global scale is 38.10 %, and range from 0.92 % in East Asian to 40.77 % in non-Finnish European (NFE) population. We analyzed the occurrence of the rs75603675 in two cohorts of patients, the first with severe/critical COVID-19 enrolled in a French hospital (42 patients), and the second with predominantly asymptomatic/pauci-symptomatic/mild COVID-19 enrolled in an Italian hospital (69 patients). We found that the TMPRSS2-c.23T minor allele frequency was similar in the two cohorts, 46.43 % and 46.38 %, respectively, and higher than the frequency in the NFE population (40.77 %). Chi-square test provided significant results (p < 0.05) when the genotype data (TMPRSS2-c.23T/c.23T homozygotes + TMPRSS2-c.23G/c.23T heterozygotes vs. TMPRSS2-c.23G/c.23G homozygotes) of the two patient groups were pooled and compared to the expected data for the NFE population, suggesting a possible pathogenetic mechanism of the p.G8V substitution. We explored the possible effects of the p.G8V substitution and found that the N-terminal region of the TMPRSS2 isoform 1 contains a signal for clathrin/AP-2-dependent endocytosis. In silico analysis predicted that the p.G8V substitution may increase the accessibility to the endocytic signal, which could help SARS-CoV-2 enter cells.

Mitochondrial metabolism sustains CD8+ T cell migration for an efficient infiltration into solid tumors.

The ability of CD8+ T cells to infiltrate solid tumors and reach cancer cells is associated with improved patient survival and responses to immunotherapy. Thus, identifying the factors controlling T cell migration in tumors is critical, so that strategies to intervene on these targets can be developed. Although interstitial motility is a highly energy-demanding process, the metabolic requirements of CD8+ T cells migrating in a 3D environment remain unclear. Here, we demonstrate that the tricarboxylic acid (TCA) cycle is the main metabolic pathway sustaining human CD8+ T cell motility in 3D collagen gels and tumor slices while glycolysis plays a more minor role. Using pharmacological and genetic approaches, we report that CD8+ T cell migration depends on the mitochondrial oxidation of glucose and glutamine, but not fatty acids, and both ATP and ROS produced by mitochondria are required for T cells to migrate. Pharmacological interventions to increase mitochondrial activity improve CD8+ T cell intratumoral migration and CAR T cell recruitment into tumor islets leading to better control of tumor growth in human xenograft models. Our study highlights the rationale of targeting mitochondrial metabolism to enhance the migration and antitumor efficacy of CAR T cells in treating solid tumors.

Outcomes and costs with the introduction of robotic-assisted thoracic surgery in public hospitals.

Robotic-assisted thoracic surgery (RATS) is an effective treatment of non-small cell lung cancer (NSCLC) but the effects of its implementation in university hospital networks has not been described. We analyzed the early clinical outcomes, estimated costs, and revenues associated with three robotic systems implemented in the Paris Public Hospital network. A retrospective study included patients who underwent RATS for NSCLC in 2019 and 2020. Ninety-day morbidity, mortality, hospital costs, and hospital revenues were described. Economic analyses were conducted either from the hospital center or from the French health insurance system perspectives. Cost drivers were tested using univariate and multivariable analyses. Sensitivity analyses were performed to assess uncertainty over in-hospital length of stay (LOS), number of robotic surgeries per year, investment cost, operating room occupancy time, maintenance cost, and commercial discount. The study included 188 patients (65.8 ± 9.3 years; Charlson 4.1 ± 1.4; stage I 76.6%). Median in-hospital LOS was 6 days [5-9.5], 90-day mortality was 1.6%. Mean hospital expenses and revenues were €12,732 ± 4914 and €11,983 ± 5708 per patient, respectively. In multivariable analysis, factors associated with hospital costs were body mass index, DLCO, major complications, and transfer to intensive care unit. Sensitivity analyses showed that in-hospital LOS (€11,802-€15,010) and commercial discounts on the list price (€11,458-€12,732) had an important impact on costs. During the first 2 years following the installation of three robotic systems in Paris Public Hospitals, the clinical outcomes of RATS for NSCLC have been satisfactory. Without commercial discount, hospital expenses would have exceeded hospital revenues.Clinical registration number CNIL, N°2221601, CERC-SFCTCV-2021-07-20-Num17_MOPI_robolution.

A surgical series on endometriosis-related diaphragmatic hernia.

BACKGROUND: Thoracic endometriosis syndrome gives rise to various clinical and radiological manifestations. We reviewed the records of patients operated for intrathoracic migration of abdominal viscera through a diaphragmatic hernia secondary to thoracic endometriosis. METHODS: We retrospectively reviewed the single-center prospective collected database of all patients operated for thoracic endometriosis during the twenty years. All cases in which an abdominal organ was found to be herniated into the thoracic cavity were retrieved. Clinical and pathological data are presented and analyzed. RESULTS: Twenty women of median age 36 (range 25-58) years were operated for endometriosis-related diaphragmatic hernia. The hernia was diagnosed concomitantly with endometriosis-related pneumothorax in 13 cases and during the exploration of catamenial thoracic pain in seven cases. There were 18 cases on the right side and two cases on the left side. The median diameter of the hernia was 8 cm (2.5-20 cm). In seventeen cases, the hernia was repaired by direct suture, and in three cases a heterologous prosthesis was positioned. At follow-up, two patients had an episode of recurrent pneumothorax. CONCLUSIONS: Diaphragmatic hernia should be ruled out in the presence of endometriosis-related pneumothorax or catamenial thoracic pain. Surgery is indicated to make a pathological diagnosis, restore anatomy, and prevent recurrence in patients presenting with pneumothorax.

Protective effect of height on long-term survival of resectable lung cancer: a new feature of the lung cancer paradox.

INTRODUCTION: Unlike most malignancies, higher body mass index (BMI) is associated with a reduced risk of lung cancer and improved prognosis after surgery. However, it remains controversial whether height, one of determinants of BMI, is associated with survival independently of BMI and other confounders. METHODS: We extracted data on all consecutive patients with resectable non-small cell lung cancer included in Epithor, the French Society of Thoracic and Cardiovascular Surgery database, over a 16-year period. Height was analysed as a continuous variable, and then categorised into four or three categories, according to sex-specific quantiles. Cox proportional hazards regression was used to estimate the association of height with survival, adjusted for age, tobacco consumption, forced expiratory volume in one second (FEV1), WHO performance status (WHO PS), American Society of Anesthesiologists (ASA) score, extent of resection, histological type, stage of disease and centre as a random effect, as well as BMI in a further analysis. RESULTS: The study included 61 379 patients. Higher height was significantly associated with better long-term survival after adjustment for other variables (adjusted HR 0.97 per 10 cm higher height, 95% CI 0.95 to 0.99); additional adjustment for BMI resulted in an identical HR. The prognostic impact of height was further confirmed by stratifying by age, ASA class, WHO PS and histological type. When stratifying by BMI class, there was no evidence of a differential association (p=0.93). When stratifying by stage of disease, the prognostic significance of height was maintained for all stages except IIIB-IV. CONCLUSIONS: Our study shows that height is an independent prognostic factor of resectable lung cancer.

The dual role of citrate in cancer.

Citrate is a key metabolite of the Krebs cycle that can also be exported in the cytosol, where it performs several functions. In normal cells, citrate sustains protein acetylation, lipid synthesis, gluconeogenesis, insulin secretion, bone tissues formation, spermatozoid mobility, and immune response. Dysregulation of citrate metabolism is implicated in several pathologies, including cancer. Here we discuss how cancer cells use citrate to sustain their proliferation, survival, and metastatic progression. Also, we propose two paradoxically opposite strategies to reduce tumour growth by targeting citrate metabolism in preclinical models. In the first strategy, we propose to administer in the tumor microenvironment a high amount of citrate, which can then act as a glycolysis inhibitor and apoptosis inducer, whereas the other strategy targets citrate transporters to starve cancer cells from citrate. These strategies, effective in several preclinical in vitro and in vivo cancer models, could be exploited in clinics, particularly to increase sensibility to current anti-cancer agents.

The potential for citrate to reinforce epigenetic therapy by promoting apoptosis.

Epigenetic drugs induce ATP depletion, promoting a glycolysis-to-oxidative phosphorylation (OXPHOS) shift which sometimes favors tumor growth by promoting necroptosis over apoptosis. To restore effective apoptosis in tumors, we propose that the administration of citrate could inhibit ATP production, activate caspase-8 (a key necroptosis inhibitor), and downregulate key anti-apoptotic proteins (Bcl-xL and MCL1).

Impact of sarcopenia indexes on survival and severe immune acute toxicity in metastatic non-small cell lung cancer patients treated with PD-1 immune checkpoint inhibitors.

BACKGROUND & AIMS: Sarcopenia has long been associated with higher toxicity induced by anti-cancer treatments and shorter survival in patients with solid tumors. The creatinine-to-cystatin ratio (CC ratio, serum creatinine/cystatin C × 100) and the sarcopenia index (SI, serum creatinine × cystatin C (CysC)-based glomerular filtration rate (eGFRCysC)) are have been reported to be correlated with skeletal muscle mass. The aim of this study is to assess primarily whether the CC ratio and the SI could predict mortality in metastatic non-small cell lung cancer (NSCLC) patients treated with PD-1 inhibitors, and secondarily their impact on severe immune-related adverse effects (irAEs). METHODS: From the prospective CERTIM cohort, we analyzed retrospectively stage IV NSCLC patients, who received PD-1 inhibitors between June 2015 and November 2020 in Cochin Hospital (Paris, France). We assessed sarcopenia measuring skeletal muscle area (SMA) by computed tomography and handgrip strength (HGS) by a hand dynamometer. RESULTS: In total, 200 patients were analyzed. The CC ratio and the IS were significantly correlated with SMA and HGS: rCC/SMA = 0.360, rSI/SMA = 0.407, rCC/HGS = 0.331, rSI/HGS = 0.370. In multivariate analysis of overall survival, a lower CC ratio (HR 1.73, P = 0.033) and a lower SI (HR 1.89, P = 0.019) were independent predictors of poor prognosis. In univariate analysis of severe irAEs, CC ratio (OR 1.01, P = 0.628) and SI (OR 0.99, P = 0.595) were not associated with a higher risk of severe irAEs. CONCLUSIONS: In metastatic NSCLC patients treated with PD-1 inhibitors, a lower CC ratio and a lower SI are independent predictors of mortality. However, they are not associated with severe irAEs.

Anatomic lung resection after immune checkpoint inhibitors for initially unresectable advanced-staged non-small cell lung cancer: a retrospective cohort analysis.

Background: Patients with initially unresectable advanced non-small cell lung cancer (NSCLC) might experience prolonged responses under immune checkpoint inhibitors (ICIs). In this setting, Multidisciplinary Tumor Board (MTB) seldomly suggest surgical resection of the primary tumor with the ultimate goal to eradicate macroscopic residual disease. Our objective was to report the perioperative outcomes of patients who underwent anatomic lung resection in these infrequent circumstances. Methods: We set a retrospective multicentric single arm study, including all patients with advanced-staged initially unresectable NSCLC (stage IIIB to IVB) who received systemic therapy including ICIs and eventually anatomical resection of the primary tumor in 10 French thoracic surgery units from January 2016 to December 2020. Coprimary endpoints were in-hospital mortality and morbidity. Secondary endpoints were the rate of complete resection of the pulmonary disease, major pathologic response, risk factors associated with post-operative complications, and overall survival. Results: Twenty-one patients (median age 64, female 62%) were included. Eighteen patients (86%) progressed after first line chemotherapy and received second line ICI. The median time between diagnosis and surgery was 22 months [interquartile range (IQR) 18-35 months]. Minimally-invasive approach was used in 10 cases (48%), with half of these requiring conversion to open thoracotomy. Nine patients (43%) presented early post-operative complications, and one patient died from broncho-pleural fistula one month after surgery. Rates of complete resection of the pulmonary disease and major pathologic response were 100% and 43%, respectively. In univariable analysis, diffusing capacity for carbon monoxide (DLCO) was the only factor associated with the occurrence of postoperative complications (P=0.027). After a median follow-up of 16.0 months after surgery (IQR, 12.0-30.0 months), 19 patients (90%) were still alive. Conclusions: Anatomic lung resections appear to be a reasonable option for initially unresectable advanced NSCLC experiencing prolonged response under ICIs. Nonetheless, minimally invasive techniques have a low applicability and post-operative complications remains higher in patients who had lower DLCO values. The late timing of surgery may also contribute to complications.

Systemic Inflammation and Lung Cancer: Is It a Real Paradigm? Prognostic Value of Inflammatory Indexes in Patients with Resected Non-Small-Cell Lung Cancer.

Background (1): Our goal was to investigate if and how pre-operative inflammatory status can influence the long-term prognosis of patients undergoing lung surgery for cancer. Materials and Methods (2): This prospective observational study includes the agreement of all operable patients to the study, who were referred to our department between 1 January 2017 and 30 December 2018. The inflammatory pre-operative status of the patients was investigated by calculating albumin, CPR (c-protein reactive), complete blood count (neutrophils, lymphocytes, platelets, hemoglobin), and some other indexes referring to inflammatory status, namely the HALP amalgamated index, platelet-to-lymphocyte ratio (PLR), neutrophil-to-lymphocytes ratio (NLR), systemic immune-inflammation index (SII), and advanced lung cancer inflammation Index (ALI). The follow-up ended in November 2021. Patient overall survival was assessed using the Kaplan-Meier method. The log-rank test was used to compare survival rates. Variables significantly associated with survival at univariate analysis were entered int Cox multivariate analysis (stepwise mode) to assess their independent character. Hazard ratios and their 95% confidence intervals were calculated. Variables associated with p < 0.05 were considered significative. Results (3): We enrolled 257 patients in our study. The overall survival of the cohort was as follows: 1 year, 96.1%; 3 year, 81.3%; and 4 year, 74.2%. Univariate analysis showed risk factors for overall survival as follows: Thoracoscore ≥ 2 (p = 0.002); histology (p = 0.002); HALP < 32.2 (p = 0.0002); SII ≥ 808.9 (p = 0.0004); ALI < 34.86 (p = 0.0005); NLr ≥ 2.29 (p = 0.01); hemoglobin < 13 g/dl (p = 0.01); PLR ≥ 196.1 (p = 0.005); pN+ (p < 0.0001); pleural invasion (p = 0.0002); and presence of vascular or lymphatic tumor emboli (p = 0.0002). Multivariate Cox analysis (stepwise model) identified Thoracoscore ≥ 2 (p = 0.02); histology, HALP < 32.2 (p = 0.004), and pN (p < 0.0001) as independent predictors of death. Conclusion (4): Pre-operative inflammatory status strongly influences long-term prognosis in patients affected by NSCLC and undergoing surgery.

Acute Influenza Infection Promotes Lung Tumor Growth by Reprogramming the Tumor Microenvironment.

One billion people worldwide get flu every year, including patients with non-small cell lung cancer (NSCLC). However, the impact of acute influenza A virus (IAV) infection on the composition of the tumor microenvironment (TME) and the clinical outcome of patients with NSCLC is largely unknown. We set out to understand how IAV load impacts cancer growth and modifies cellular and molecular players in the TME. Herein, we report that IAV can infect both tumor and immune cells, resulting in a long-term protumoral effect in tumor-bearing mice. Mechanistically, IAV impaired tumor-specific T-cell responses, led to the exhaustion of memory CD8+ T cells and induced PD-L1 expression on tumor cells. IAV infection modulated the transcriptomic profile of the TME, fine-tuning it toward immunosuppression, carcinogenesis, and lipid and drug metabolism. Consistent with these data, the transcriptional module induced by IAV infection in tumor cells in tumor-bearing mice was also found in human patients with lung adenocarcinoma and correlated with poor overall survival. In conclusion, we found that IAV infection worsened lung tumor progression by reprogramming the TME toward a more aggressive state.

Reaching multidisciplinary consensus on the management of non-bulky/non-infiltrative stage IIIA N2 non-small cell lung cancer.

INTRODUCTION: The optimal management of patients with non-bulky/non-infiltrative stage IIIA N2 non-small cell lung cancer (NSCLC) remains controversial. In this modified Delphi study from France, we aimed to generate agreement through multidisciplinary decision-making on the clinical management of patients with non-bulky/non-infiltrative N2 NSCLC. METHODS: An expert panel of 30 physicians from different specialities completed two Delphi rounds of a 76-item questionnaire, pertaining to: pathological confirmation of N2 disease; initial treatment approach; treatment approach in case of disease progression/stability following neoadjuvant chemotherapy; treatment approach taking into account various patient and tumour characteristics. Each questionnaire item was scored using a 9-point Likert scale. Consensus in agreement was achieved if ≥ 80 % of responses to a questionnaire item were scored between 7 and 9 and if the median value of the score to the item was ≥ 7. RESULTS: Regarding the pathologic confirmation of N2 disease, agreement (up to 100 %) was reached on endobronchial ultrasound/endoscopic ultrasound as the preferred method of initial mediastinal staging for paratracheal lymph nodes. There was also panellist agreement (up to 93 %) on the adoption as first-line treatment of surgery and (neo)adjuvant chemotherapy in patients with single-station disease, and of concurrent chemoradiotherapy followed by adjuvant immunotherapy in those with multi-station N2 disease. Panellists further agreed on the use of a non-surgical strategy, i.e., concurrent chemoradiotherapy with adjuvant immunotherapy, in patients with single-station N2 disease in case of: involvement of ≥ 2 mediastinal lymph nodes; disease progression following neoadjuvant chemotherapy; compromised cardiopulmonary function if compatible with radiotherapy; anticipated right pneumonectomy. CONCLUSIONS: This Delphi study reinforces the importance of multidisciplinary discussions leading to the best individual approach to the clinical management of patients with non-bulky/non-infiltrative N2 NSCLC, a challenging heterogeneous population.

Blocking interleukin-23 ameliorates neuromuscular and thymic defects in myasthenia gravis.

Acetylcholine receptor (AChR) myasthenia gravis (MG) is a chronic autoimmune disease characterized by muscle weakness. The AChR+ autoantibodies are produced by B-cells located in thymic ectopic germinal centers (eGC). No therapeutic approach is curative. The inflammatory IL-23/Th17 pathway is activated in the thymus as well as in the blood and the muscle, contributing to the MG pathogenic events. We aimed to study a potential new therapeutic approach that targets IL-23p19 (IL-23) in the two complementary preclinical MG models: the classical experimental MG mouse model (EAMG) based on active immunization and the humanized mouse model featuring human MG thymuses engrafted in NSG mice (NSG-MG). In both preclinical models, the anti-IL-23 treatment ameliorated MG clinical symptoms. In the EAMG, the treatment reduced IL-17 related inflammation, anti-AChR IgG2b antibody production, activated transduction pathway involved in muscle regeneration and ameliorated the signal transduction at the neuromuscular junction. In the NSG-MG model, the treatment reduced pathogenic Th17 cell population and expression of genes involved in eGC stabilization and B-cell development in human MG thymus biopsies. Altogether, these data suggest that a therapy targeting IL-23p19 may promote significant clinical ameliorations in AChR+ MG disease due to concomitant beneficial effects on the thymus and skeletal muscle defects.

Prognostic score and sex-specific nomograms to predict survival in resectable lung cancer: A French nationwide study from the Epithor cohort database.

Background: Prognostic assessment in patients undergoing cancer treatments is of paramount importance to plan subsequent management. In resectable lung cancer availability of an easy-to use nomogram to predict long-term outcome would be extremely useful to identify high-risk patients in the era of perioperative targeted and immune therapies. Methods: We retrieved clinical, surgical and pathological data of all consecutive patients included in Epithor, the database of French Society of Thoracic and Cardiovascular Surgery, and operated on between 2003 and 2020 for non-small cell lung cancer in a curative intent. The primary endpoint was overall survival up to 5 years. We assessed prognostic significance of available variables using Cox modelling, in the whole dataset, and in men and in women separately, and performed temporal validation. Finally, we constructed two sex-specific nomograms. Survivals by fifths of score were assessed in the development and temporal validation sets. Findings: The study included 62,633 patients (43,551 men and 19,082 women). Median survival time was 9.2 years. Nine factors had strong prognostic impact and were used to construct nomograms. The optimism-corrected c statistic for the prognostic score was 0.689 in the development sample, and 0.726 (95% CI 0.718-0.735) in the temporal validation sample. All differences between adjacent fifths of score were significant (P < 0.0001). Figures of 3-year OS by fifths of score were 92.2%, 83.0%, 74.3%, 64.0%, and 43.4%, respectively, in the development set and 93.3%, 88.4%, 81.0%, 73.7%, 55.7% in the temporal validation set. Performance of score was maintained when stratifying by stage of diseases. Interpretation: In the present work, we report evidence that long-term overall survival after resection of NSCLC can be predicted by an easy to construct and use composite score taking into account both host and tumour related factors. Funding: Epithor is funded by FSTCVS.

Bariatric surgery reduces the risk of pancreatic cancer in individuals with obesity before the age of 50 years: A nationwide administrative data study in France.

BACKGROUND: Obesity is a well-established risk factor for pancreatic cancer. Bariatric surgery has demonstrated superior results in terms of weight loss and obesity-related comorbidities compared to medical and behavioral treatments. The aim of this study is to evaluate the effect of bariatric surgery on pancreatic cancer incidence in individuals with obesity. METHOD: Individuals with a diagnosis of obesity were retrieved from the French national hospital discharge database. We conducted a cohort study comparing the risk to develop pancreatic cancer in individuals with obesity with and without history of bariatric surgery; the inverse probability of treatment weighting (IPTW) method was performed to assess the uncertainty around the results. Moreover, a subgroup analysis according to age at the time of bariatric surgery was performed to study its impact on the risk of pancreatic cancer. Finally, possible differences depending on the type of bariatric procedure (sleeve gastrectomy vs Roux-en-Y gastric bypass) were also explored. RESULTS: 160,129 (Bariatric Surgery group) and 1,263,804 (control group) patients with 5.2 ± 1.9 and 6.0 ± 1.9 years of follow-up respectively were included. A significant reduced risk to develop pancreatic cancer during follow-up was identified for the bariatric surgery group in the overall population (HR: 0.567). However, this reduced risk was only observed in the 18-50 years group. These results were furtherly confirmed after IPTW analysis. No difference was found between different bariatric procedures. CONCLUSION: Bariatric surgery has a protective effect against pancreatic cancer in the 18-50 years population. High-quality prospective studies are needed to confirm these results.

Regulatory T cells infiltrate the tumor-induced tertiary lymphoïd structures and are associated with poor clinical outcome in NSCLC.

On one hand, regulatory T cells (Tregs) play an immunosuppressive activity in most solid tumors but not all. On the other hand, the organization of tumor-infiltrating immune cells into tertiary lymphoid structures (TLS) is associated with long-term survival in most cancers. Here, we investigated the role of Tregs in the context of Non-Small Cell Lung Cancer (NSCLC)-associated TLS. We observed that Tregs show a similar immune profile in TLS and non-TLS areas. Autologous tumor-infiltrating Tregs inhibit the proliferation and cytokine secretion of CD4+ conventional T cells, a capacity which is recovered by antibodies against Cytotoxic T-Lymphocyte-Associated protein-4 (CTLA-4) and Glucocorticoid-Induced TNFR-Related protein (GITR) but not against other immune checkpoint (ICP) molecules. Tregs in the whole tumor, including in TLS, are associated with a poor outcome of NSCLC patients, and combination with TLS-dendritic cells (DCs) and CD8+ T cells allows higher overall survival discrimination. Thus, Targeting Tregs especially in TLS may represent a major challenge in order to boost anti-tumor immune responses initiated in TLS.