Dynamic magnetic resonance imaging in unilateral diaphragm eventration: knowledge improvement before and after plication.

BACKGROUND: The assessment before surgical plication for unilateral hemidiaphragm (HD) eventration is not clearly defined and no precise criteria exist to really understand which patient is operated with which results depending on the technique used. The goal of this study was to evaluate the place of dynamic magnetic resonance imaging (dMRI) before and after plication by developing measurement criteria. METHODS: Between 2006 and 2017, 18 patients (group1: Gp1) were operated for eventrations, 15 left-sided (Gp1L) and 3 right-sided (Gp1R). All had preoperative and postoperative evaluations including dMRI and pulmonary function tests. Five healthy volunteer subjects (group2: Gp2) had the same imaging protocol. For each HD, we measured the respiratory excursion at three fixed points (S1, S2, S3) and the height of curvature on sagittal plane. We also searched for upward paradoxical diaphragm movements. RESULTS: Before surgery, no excursion (n=13) or extremely reduced excursion (n=5) was detected on the injured HD (IHD) in Gp1. Upward paradoxical movements were identified only in Gp1L (n=6). Compared with Gp2 subjects, the healthy HD for Gp1L patients had significantly reduced excursion values at three sites S1 (P=0.038), S2 (P=0.006), and S3 (P=0.004). After plication, the decreasing height of curvature confirmed a tightening of the IHD in all patients (median value from 100 to 39.5 mm in Gp1L and 92 to 74 mm in Gp1R, P=0.0001). All upward paradoxical movements disappeared. Healthy HD excursions in Gp1L normalised their values. All those imaging improvements were correlated with postoperative improvements of dyspnoea score (P<0.0001) and vital capacity (P=0.002). CONCLUSIONS: dMRI and the standardised grid we developed not only improve the knowledge of unilateral diaphragm eventration but also permit to evaluate the quality of its surgical repair. It also demonstrates that a dysfunction of the healthy HD contralateral to eventration is possible and reversible after plication of the IHD.

NF1 mutations identify molecular and clinical subtypes of lung adenocarcinomas.

The tumor suppressor gene neurofibromin 1 (NF1) is a major regulator of the RAS-MAPK pathway. NF1 mutations occur in lung cancer but were not extensively explored. We hypothesized that NF1-mutated tumors could define a specific population with a distinct clinical and molecular profile. We performed NF1 sequencing using next generation sequencing (NGS) in 154 lung adenocarcinoma surgical specimens with known KRAS, EGFR, TP53, BRAF, HER2, and PIK3CA status, to evaluate the molecular and clinical specificities of NF1-mutated lung cancers. Clinical data were retrospectively collected, and their associations with molecular profiles assessed. In this series, 24 tumors were NF1 mutated (17.5%) and 11 were NF1 deleted (8%). There was no mutation hotspot. NF1 mutations were rarely associated with other RAS-MAPK pathway mutations. Most of patients with NF1 alterations were males (74.3%) and smokers (74.3%). Overall survival and disease-free survival were statistically better in patients with NF1 alterations (N = 34) than in patients with KRAS mutations (N = 30) in univariate analysis. Our results confirm that NF1 is frequently mutated and represents a distinct molecular and clinical subtype of lung adenocarcinoma.

Clinical and molecular characteristics of unicentric mediastinal Castleman disease.

BACKGROUND: Unicentric mediastinal Castleman disease (CD) is a rare condition, poorly characterized due to the small number of cases and the absence of genomic study. We analyzed clinical, radiological, histological and genomic patterns associated with mediastinal CD in a substantial case series.Methods: We retrospectively reviewed cases of unicentric mediastinal CD managed in 2 French thoracic surgery departments between 1988 and 2012. Clinical, radiological, surgical and pathological data were recorded. On available FFPE blocks we performed mutation screening by next-generation-sequencing, using AmpliSeq™ Cancer Hotspot v2 (Life Technologies) and immunohistochemistry (IHC) (AKT-mTOR pathway). RESULTS: Eleven patients were identified (mean age 41±15 years, sex-ratio 0.8, median follow-up 78 months). Surgical approach was thoracotomy (n=6), sternotomy (n=4), and VATS (n=1). Additional procedures included thymectomy in three cases, mediastinal lymphadenectomy in two cases, and bilobectomy in one case. One patient presented local relapse as a follicular dendritic cell sarcoma, leading to death 48 months after the first resection. Within 9 patients whose FFPE blocks were available, 2 mutations were found: VHL (p.F119L, 35%, n=1) and JAK3 (p.V718L, 53%, n=1). Phospho-AKT and phospho-mTOR stainings were negative in all cases, whereas phospho-S6RP staining was positive in eight cases, mainly in interfollicular cell cytoplasm. CONCLUSIONS: From this series of patients with unicentric mediastinal CD, we observed 2 cases of potential driver mutations and 8 cases of phospho-S6RP activation not related to AKT-mTOR. Larger studies are required to decipher more precisely the molecular abnormalities and potential therapeutic targets underlying this uncommon condition.

Surgical resection of pulmonary inflammatory pseudotumors: long-term outcome.

Background Pulmonary inflammatory pseudotumors are rare lesions that remain problematic in several aspects, especially regarding the therapeutic strategy. The goal of this study was to evaluate long-term survival in a multicenter series of patients who required surgery for pulmonary inflammatory pseudotumors. Methods Thirty-six cases of pulmonary inflammatory pseudotumors, operated on in 3 French thoracic surgery departments between 1989 and 2015, were studied retrospectively. We recorded pre-, peri- and postoperative data for each patient, and long-term survival was analyzed. Results There were 22 men and 14 women. Mean age was 53.5 years (range 14-81 years). Three pneumonectomies, 1 bilobectomy, 19 lobectomies, 2 segmentectomies, 10 wedge resections, and 1 biopsy were performed. Complete resection was carried out in 32 (88.8%) patients. Median follow-up was 76 months. Five-year and 10-year survival rates were respectively 86.8% and 81.7% (96% and 90% for patients with R0 resection). Conclusions Long-term survival was excellent for patients with pulmonary inflammatory pseudotumors who benefited from surgery, especially when surgical resection was complete. These results confirm that surgical resection must be proposed as the first-line treatment for patients with pulmonary inflammatory pseudotumors.

Induction of resident memory T cells enhances the efficacy of cancer vaccine.

Tissue-resident memory T cells (Trm) represent a new subset of long-lived memory T cells that remain in tissue and do not recirculate. Although they are considered as early immune effectors in infectious diseases, their role in cancer immunosurveillance remains unknown. In a preclinical model of head and neck cancer, we show that intranasal vaccination with a mucosal vector, the B subunit of Shiga toxin, induces local Trm and inhibits tumour growth. As Trm do not recirculate, we demonstrate their crucial role in the efficacy of cancer vaccine with parabiosis experiments. Blockade of TFGß decreases the induction of Trm after mucosal vaccine immunization, resulting in the lower efficacy of cancer vaccine. In order to extrapolate this role of Trm in humans, we show that the number of Trm correlates with a better overall survival in lung cancer in multivariate analysis. The induction of Trm may represent a new surrogate biomarker for the efficacy of cancer vaccine. This study also argues for the development of vaccine strategies designed to elicit them.

Can mathematics replace anatomy to establish recommendations in lung cancer surgery?

The greater the number of lymph node (LN) sampled (NLNsS) during lung cancer surgery, the lower the risk of underestimating the pN-status and the better the outcome of the pN0-patients due to stage-migration. Thus, regarding LN sampling "to be or not to be", number is the question. Recent studies advocate removing 10 LNs. The most suitable NLNsS is unfortunately impossible to establish by mathematics. A too high NLNsS variability exists, based on anatomy, surgery and pathology. The methodology may vary according to Inter-institutional differences in the surgical approach regarding LN inspection and number sampling. The NLNsS increases with the type of resection: sublobar, lobectomy or pneumonectomy. Concerning pathology, one LN may be divided into several pieces, leading to number overestimation. The pathological examination is limited by the number of slices analyzed by LN. The examined LNs can arbitrarily depend on the probability of detecting nodal metastasis. In fact, the only way to ensure the best NLNsS and the best pN-staging is to remove all LNs from the ipsilateral mediastinal and hilar LN-stations as they are discovered by thoroughly dissecting their anatomical locations. In doing so, a deliberate lack of harvest of LNs is unlikely, number turns out not to be the question anymore and a low NLNsS no longer means incomplete surgery. This prevents from judging as incomplete a complete LN dissection in a patient with a small NLNsS and from considering as complete a true incomplete one in a patient with a great NLNsS. Precise information describing the course of the operation and furnished in the surgeon's reports is also advisable to further improve the quality of LN-dissection, which ultimately might be beneficial in the long-term to patients. However, that procedure is of limited interest in pN-staging if LNs are not thoroughly examined and also described by the pathologist.

Medical and Economic Evaluation of FOREseal Bioabsorbable Reinforcement Sleeves Compared With Current Standard of Care for Reducing Air Leakage Duration After Lung Resection for Malignancy: A Randomized Trial.

OBJECTIVE: The objective of this study was to determine the efficacy of alginate staple-line reinforcement of fissure openings as compared with stapling alone, with or without tissue sealant or glue, in reducing the incidence and duration of air leakage after pulmonary lobectomy for malignancy. SUMMARY BACKGROUND DATA: No randomized trial evaluating alginate staple-line reinforcement has been performed to date. METHODS: The Staple-line Reinforcement for Prevention of Pulmonary Air Leakage study was a multicenter randomized trial, with blinded evaluation of endpoints. Patients over 18 years of age scheduled for elective open lobectomy or bilobectomy for malignancy were eligible for enrollment. At thoracotomy, patients were deemed ineligible if an unanticipated pneumonectomy was indicated, or if air leakage occurred after the liberation of pleural adhesions. Otherwise, if the fissure was incomplete or the lung had an emphysematous appearance, patients were randomized to either standard management or interventional procedure consisting of fissure opening with linear cutting staplers buttressed with paired alginate sleeves (FOREseal). The number of eligible patients necessary in each randomization arm was estimated to be 190, and an outcomes analysis was performed on an intention-to-treat basis. RESULTS: Of the 611 patients consented to study enrollment, 380 met the inclusion criteria and were randomized. Based on an intention-to-treat analysis, the primary endpoint of air leak duration was not different between the 2 groups: 1 day (range: 0-2 d) in the FOREseal group and 1 day (range: 0-3 d) in the control group (P = 0.8357). In addition, the 2 groups were similar in terms of the proportion of patients presenting with prolonged air leakage (7.8% in the FOREseal group vs 11.3% in the control group, P = 0.264) and the average duration of chest drainage (P = 0.107). Procedure costs were comparable for both groups. CONCLUSIONS: FOREseal did not demonstrate a significant advantage over standard treatment alone.

Different prognostic impact of STK11 mutations in non-squamous non-small-cell lung cancer.

STK11 is commonly mutated in lung cancer. In light of recent experimental data showing that specific STK11 mutants could acquire oncogenic activities due to the synthesis of a short STK11 isoform, we investigated whether this new classification of STK11 mutants could help refine its role as a prognostic marker. We conducted a retrospective high-throughput genotyping study in 567 resected non-squamous non-small-cell lung cancer (NSCLC) patients. STK11 exons 1 or 2 mutations (STK11ex1-2) with potential oncogenic activity were analyzed separately from exons 3 to 9 (STK11ex3-9). STK11ex1-2 and STK11ex3-9 mutations occurred in 5% and 14% of NSCLC. STK11 mutated patients were younger (P = .01) and smokers (P< .0001). STK11 mutations were significantly associated with KRAS and inversely with EGFR mutations. After a median follow-up of 7.2 years (95%CI 6.8-.4), patients with STK11ex1-2 mutation had a median OS of 24 months (95%CI 15-57) as compared to 69 months (95%CI 56-93) for wild-type (log-rank, P = .005) and to 91 months (95%CI 57-unreached) for STK11ex3-9 mutations (P = .003). In multivariate analysis, STK11ex1-2 mutations remained associated with a poor prognosis (P = .002). Results were validated in two public datasets. Western blots showed that STK11ex1-2 mutatedtumors expressed short STK11 isoforms. Finally using mRNAseq data from the TCGA cohort, we showed that a stroma-derived poor prognosis signature was enriched in STK11ex1-2 mutated tumors. All together our results show that STK11ex1-2 mutations delineate an aggressive subtype of lung cancer for which a targeted treatment through STK11 inhibition might offer new opportunities.