Porphyrin Atropisomerism as a Molecular Engineering Tool in Medicinal Chemistry, Molecular Recognition, Supramolecular Assembly, and Catalysis.

Porphyrin atropisomerism, which arises from restricted σ-bond rotation between the macrocycle and a sufficiently bulky substituent, was identified in 1969 by Gottwald and Ullman in 5,10,15,20-tetrakis(o-hydroxyphenyl)porphyrins. Henceforth, an entirely new field has emerged utilizing this transformative tool. This review strives to explain the consequences of atropisomerism in porphyrins, the methods which have been developed for their separation and analysis and present the diverse array of applications. Porphyrins alone possess intriguing properties and a structure which can be easily decorated and molded for a specific function. Therefore, atropisomerism serves as a transformative tool, making it possible to obtain even a specific molecular shape. Atropisomerism has been thoroughly exploited in catalysis and molecular recognition yet presents both challenges and opportunities in medicinal chemistry.

Personalised exercise rehabilitation in cancer survivorship: the percs triage and referral system study protocol.

BACKGROUND: To effectively embed exercise rehabilitation in cancer survivorship care, a co-ordinated system of acute and community exercise rehabilitation services, forming a stepped model of care, is recommended. Patients can be directed to the exercise rehabilitation service which best meets their needs through a system of assessment, triage and referral. Triage and referral systems are not yet widely applied in cancer survivorship practice and need to be evaluated in real-world contexts. The PERCS (Personalised Exercise Rehabilitation in Cancer Survivorship) study aims to evaluate the real-world application of an exercise rehabilitation triage and referral system in cancer survivors treated during the COVID-19 pandemic. Secondary aims are to evaluate change in physical and psychosocial outcomes, and to qualitatively evaluate the impact of the system and patient experiences, at three months after application of the triage and referral system. METHODS: This study will assess the implementation of an exercise rehabilitation triage and referral system within the context of a physiotherapy-led cancer rehabilitation clinic for cancer survivors who received cancer treatment during the COVID-19 pandemic. The PERCS triage and referral system supports decision making in exercise rehabilitation referral by recommending one of three pathways: independent exercise; fitness professional referral; or health professional referral. Up to 100 adult cancer survivors treated during the COVID-19 pandemic who have completed treatment and have no signs of active disease will be recruited. We will assess participants' physical and psychosocial wellbeing and evaluate whether medical clearance for exercise is needed. Participants will then be triaged to a referral pathway and an exercise recommendation will be collaboratively decided. Reassessment will be after 12 weeks. Primary outcomes are implementation-related, guided by the RE-AIM framework. Secondary outcomes include physical function, psychosocial wellbeing and exercise levels. Qualitative analysis of semi-structured interviews guided by the Consolidated Framework for Implementation Research (CFIR) will provide insights on implementation and system impact. DISCUSSION: The PERCS study will investigate the real-world application of a cancer rehabilitation triage and referral system. This will provide proof of concept evidence for this triage approach and important insights on the implementation of a triage system in a specialist cancer centre. TRIAL REGISTRATION: This study is registered on ClinicalTrials.gov, registration number: NCT05615285, date registered: 21st October 2022.

Antitumor Immunity Mediated by Photodynamic Therapy Using Injectable Chitosan Hydrogels for Intratumoral and Sustained Drug Delivery.

Photodynamic therapy (PDT) is an anticancer therapy with proven efficacy; however, its application is often limited by prolonged skin photosensitivity and solubility issues associated with the phototherapeutic agents. Injectable hydrogels which can effectively provide intratumoral delivery of photosensitizers with sustained release are attracting increased interest for photodynamic cancer therapies. However, most of the hydrogels for PDT applications are based on systems with high complexity, and often, preclinical validation is not provided. Herein, we provide a simple and reliable pH-sensitive hydrogel formulation that presents appropriate rheological properties for intratumoral injection. For this, Temoporfin (m-THPC), which is one of the most potent clinical photosensitizers, was chemically modified to introduce functional groups that act as cross-linkers in the formation of chitosan-based hydrogels. The introduction of -COOH groups resulted in a water-soluble derivative, named PS2, that was the most promising candidate. Although PS2 was not internalized by the target cells, its extracellular activation caused effective damage to the cancer cells, which was likely mediated by lipid peroxidation. The injection of the hydrogel containing PS2 in the tumors was monitored by high-frequency ultrasounds and in vivo fluorescence imaging which confirmed the sustained release of PS2 for at least 72 h. Following local administration, light exposure was conducted one (single irradiation protocol) or three (multiple irradiation protocols) times. The latter delivered the best therapeutic outcomes, which included complete tumor regression and systemic anticancer immune responses. Immunological memory was induced as ∼75% of the mice cured with our strategy rejected a second rechallenge with live cancer cells. Additionally, the failure of PDT to treat immunocompromised mice bearing tumors reinforces the relevance of the host immune system. Finally, our strategy promotes anticancer immune responses that lead to the abscopal protection against distant metastases.

International consensus on the management of metastatic gastric cancer: step by step in the foggy landscape : Bertinoro Workshop, November 2022.

BACKGROUND: Many gastric cancer patients in Western countries are diagnosed as metastatic with a median overall survival of less than twelve months using standard chemotherapy. Innovative treatments, like targeted therapy or immunotherapy, have recently proved to ameliorate prognosis, but a general agreement on managing oligometastatic disease has yet to be achieved. An international multi-disciplinary workshop was held in Bertinoro, Italy, in November 2022 to verify whether achieving a consensus on at least some topics was possible. METHODS: A two-round Delphi process was carried out, where participants were asked to answer 32 multiple-choice questions about CT, laparoscopic staging and biomarkers, systemic treatment for different localization, role and indication of palliative care. Consensus was established with at least a 67% agreement. RESULTS: The assembly agreed to define oligometastases as a "dynamic" disease which either regresses or remains stable in response to systemic treatment. In addition, the definition of oligometastases was restricted to the following sites: para-aortic nodal stations, liver, lung, and peritoneum, excluding bones. In detail, the following conditions should be considered as oligometastases: involvement of para-aortic stations, in particular 16a2 or 16b1; up to three technically resectable liver metastases; three unilateral or two bilateral lung metastases; peritoneal carcinomatosis with PCI ≤ 6. No consensus was achieved on how to classify positive cytology, which was considered as oligometastatic by 55% of participants only if converted to negative after chemotherapy. CONCLUSION: As assessed at the time of diagnosis, surgical treatment of oligometastases should aim at R0 curativity on the entire disease volume, including both the primary tumor and its metastases. Conversion surgery was defined as surgery on the residual volume of disease, which was initially not resectable for technical and/or oncological reasons but nevertheless responded to first-line treatment.

MicroRNA dysregulation and therapeutic opportunities in esophageal diseases.

MicroRNAs (miRNAs) are a class of small endogenous RNA molecules between 18 and 25 nucleotides long. The primary function of miRNAs is in the posttranscriptional regulation of mRNA targets through RNA interference culminating in mRNA degradation or translational repression. MiRNAs are fundamental in physiological and pathological processes such as cell proliferation, differentiation, apoptosis, and inflammation. Among this includes the uncovered potential of miRNAs in overall esophageal disease with a focus on the clinicopathologic allergic disease eosinophilic esophagitis (EoE), gastroesophageal reflux disease (GERD), and the tumorigenic continuum from Barrett's esophagus (BE) toward esophageal adenocarcinoma (EAC). Although these pathologies are distinct from one another, they share pathophysiological elements such as an intense inflammatory milieu, esophageal dysfunction, and as presented in this review, an overlap in miRNA expression which contributes to overall esophageal disease. The overlap in the dysregulated miRNA transcriptome of these pathologies highlights the key role miRNAs play in contributing to esophageal disease progression. Owing to this notable dysregulation, there is an attractive utility for miRNAs as diagnostic and prognostic biomarkers in esophageal diseases that already require invasive endoscopies and biopsy retrieval. In this review miRNAs within EoE, GERD, BE, EAC, and esophageal achalasia are discussed, as well as reviewing a core set of miRNAs shared in the disease progression among some of these pathologies, along with the potential utility of targeting miRNAs as therapeutic options in overall esophageal disease.

Acidosis significantly alters immune checkpoint expression profiles of T cells from oesophageal adenocarcinoma patients.

Tumour acidosis contributes to cancer progression by inhibiting anti-tumour immunity. However, the effect of acidosis on anti-tumour T cell phenotypes in oesophageal adenocarcinoma (OAC) is unknown. Therefore, this study investigated the effect of acidosis on anti-tumour T cell profiles and if immune checkpoint blockade (ICB) could enhance anti-tumour T cell immunity under acidosis. Acidic conditions substantially altered immune checkpoint expression profiles of OAC patient-derived T cells, upregulating TIM-3, LAG-3 and CTLA-4. Severe acidosis (pH 5.5) significantly decreased the percentage of central memory CD4+ T cells, an effect that was attenuated by ICB treatment. ICB increased T cell production of IFN-γ under moderate acidosis (pH 6.6) but not severe acidosis (pH 5.5) and decreased IL-10 production by T cells under severe acidic conditions only. A link between lactate and metastasis was also depicted; patients with nodal metastasis had higher serum lactate levels (p = 0.07) which also positively correlated with circulating levels of pro-angiogenic factor Tie-2. Our findings establish that acidosis-induced upregulation of immune checkpoints on T cells may potentially contribute to immune evasion and disease progression in OAC. However, acidic conditions curtailed ICB efficacy, supporting a rationale for utilizing systemic oral buffers to neutralize tumour acidity to improve ICB efficacy. Study schematic-PBMCs were isolated from OAC patients (A) and expanded ex vivo for 7 days using anti-CD3/28 +IL-2 T cell activation protocol (B) and further cultured for 48 h under increasing acidic conditions in the absence or presence of immune checkpoint blockade (nivolumab, ipilimumab or dual nivolumab + ipilimumab) (C). Immunophenotyping was then carried out to assess immune checkpoint expression profiles and anti-tumour T cell phenotypes (D). Serum lactate was assessed in OAC patients (E-F) and levels were correlated with patient demographics (G) and the levels of circulating immune/pro-angiogenic cytokines that were determined by multiplex ELISA (H). Key Findings-severe acidic conditions upregulated multiple immune checkpoints on T cells (I). Efficacy of ICB was curtailed under severe acidic conditions (J). Circulating lactate levels positively correlated with circulating levels of pro-angiogenic factor tie-2 and higher serum lactate levels were found in patients who had nodal metastasis (K).

Translating evidence in a priority setting partnership: knowledge gaps between healthcare providers and oesophageal cancer patients.

INTRODUCTION: Despite the fact that health information is now more accessible than ever, knowledge gaps remain between patients and healthcare providers (HCPs). To date, the patients' need for information following a diagnosis of oesophageal cancer has not been adequately met. PURPOSE: The purpose of this study was to identify why knowledge gaps exist between oesophageal cancer patients and HCPs and how to address them. METHODS: Purposive sampling of a group of people living with and after oesophageal cancer who had participated in a priority-setting partnership where 45% of questions from patients had existing evidence-based answers. A 7-set question series was developed for use in a patient/HCP focus group in addition to 11 individual phone interviews with survivors of oesophageal cancer. Qualitative semistructured interviews were conducted to explore oesophageal cancer patients' access to information. The data was analysed thematically, which involved coding all patient transcripts before identifying and reviewing key themes. RESULTS: The three primary themes that emerged were as follows: opportunity (HCP team factors and relationship development), ability (patient factors) and priority (pacing of information delivery). CONCLUSION: Effective communication between patients and HCPs was identified as an integral component of the enhancement of patient knowledge. HCPs should continue to refine and improve methods of information delivery and encourage conversations regarding information preferences.

Single-center experience in implementation of endoscopic surveillance protocol after esophagectomy.

Esophageal cancer has a notably high recurrence rate with a paucity of robust evidence in defining the optimal surveillance strategy. The surveillance protocol at our institution comprises of annual esophagogastroduodenoscopy (OGD) from years 1 to 5 postoperatively. This study aims to evaluate the implementation of the endoscopic surveillance at our center and ascertain the value of endoscopy in detecting local recurrence after esophagectomy. A retrospective cohort review of all patients (320 patients) who underwent esophagectomy between 2013 and 2018 was conducted. The local esophageal cancer database and corresponding OGD reports were accessed to obtain data on demographics, operation details, local recurrence, and endoscopy performed. 1086 OGDs were performed between 2014 and 2020, broadly categorized to surveillance and symptomatic OGDs; 555 and 531, respectively. Surveillance OGDs detected four asymptomatic local recurrences, of which only one was treated with curative intent. Symptomatic OGDs resulted in a higher yield for the detection of local recurrence compared with surveillance endoscopy; 5% versus 0.7%, with overall median time-to-recurrence of 11.5 months (95% confidence interval 9-17). Of local recurrences, 85.7% occurred within the first 2 years postoperatively. The proportion of endoscopic findings differed between intensive and ad hoc surveillance cohorts for strictures, esophagitis, Barrett's esophagus, and sloughing. Thirteen patients were diagnosed with histologically confirmed Barrett's with no subsequent local recurrences. Surveillance endoscopy had a low positive yield rate with subsequent minimal survival benefits. Therefore, it is prudent to consider an alternative protocol that focuses on the period with the highest risk of recurrence and symptom presentation.

What works best in hiatus hernia repair, sutures alone, absorbable mesh or non-absorbable mesh? A systematic review and network meta-analysis of randomized clinical trials.

Laparoscopic hiatal hernia repair (HHR) and fundoplication is a common low risk procedure providing excellent control of gastro-oesophageal reflux disease and restoring of normal anatomy at the hiatus. HHR may fail, however, resulting in hiatus hernia (HH) recurrence, and the use of tension-free mesh-augmented hernioplasty has been proposed to reduce recurrence. Previous research on this topic has been heterogeneous, including study methods, mesh type used and technique performed. A systematic review and network meta-analysis were carried out. An electronic systematic research was carried out using 'PUBMED', 'EMBASE', 'Medline (OVID)' and 'Web of Science', of articles identifying HHR with suture cruroplasty, non-absorbable mesh (NAM) and absorbable mesh (AM) reinforcement. Eight RCTs with 766 patients were evaluated. NAM had significantly (P < 0.05) lower early recurrence rates (OR: 0.225, 95% CI 0.0342, 0.871) compared with suture repair alone; however, no differences in late recurrences were evident. For AM, no difference in early (0.508, 95% CI 0.0605, 4.81) or late (1.07. 95% CI 0.116, 11.4) recurrence rates were evident compared with the suture only group. Major complication rates were similar in all groups. NAM reinforcement significantly reduced early HH recurrence when compared with sutured cruroplasty alone; however, late recurrence rates were similar with all techniques. Given the limited data in comparing AM with NAM, this study was unable to conclude which composition was significant. We emphasize caution when interpreting small sample size RCTs, and recommend more research with larger randomized studies.

Unraveling the Pivotal Role of Atropisomerism for Cellular Internalization.

The intrinsic challenge of large molecules to cross the cell membrane and reach intracellular targets is a major obstacle for the development of new medicines. We report how rotation along a single C-C bond, between atropisomers of a drug in clinical trials, improves cell uptake and therapeutic efficacy. The atropisomers of redaporfin (a fluorinated sulfonamide bacteriochlorin photosensitizer of 1135 Da) are separable and display orders of magnitude differences in photodynamic efficacy that are directly related to their differential cellular uptake. We show that redaporfin atropisomer uptake is passive and only marginally affected by ATP depletion, plasma proteins, or formulation in micelles. The α4 atropisomer, where meso-phenyl sulfonamide substituents are on the same side of the tetrapyrrole macrocycle, exhibits the highest cellular uptake and phototoxicity. This is the most amphipathic atropisomer with a conformation that optimizes hydrogen bonding (H-bonding) with polar head groups of membrane phospholipids. Consequently, α4 binds to the phospholipids on the surface of the membrane, flips into the membrane to adopt the orientation of a surfactant, and eventually diffuses to the interior of the cell (bind-flip mechanism). We observed increased α4 internalization by cells of the tumor microenvironment in vivo and correlated this to the response of photodynamic therapy when tumor illumination was performed 24 h after α4 administration. These results show that properly orientated aryl sulfonamide groups can be incorporated into drug design as efficient cell-penetrating motifs in vivo and reveal the unexpected biological consequences of atropisomerism.

Advances in the curative management of oesophageal cancer.

The incidence of oesophageal cancer, in particular adenocarcinoma, has markedly increased over the last four decades with adenocarcinoma becoming the dominant subtype in the West, and mortality rates are high. Nevertheless, overall survival of patients with oesophageal cancer has doubled in the past 20 years, with earlier diagnosis and improved treatments benefiting those patients who can be treated with curative intent. Advances in endotherapy, surgical approaches, and multimodal and other combination therapies have been reported. New vistas have emerged in targeted therapies and immunotherapy, informed by new knowledge in genomics and molecular biology, which present opportunities for personalised cancer therapy and novel clinical trials. This review focuses exclusively on the curative intent treatment pathway, and highlights emerging advances.

The Complexity of Defining Postoperative Pneumonia After Esophageal Cancer Surgery: A Spectrum of Lung Injury Rather Than a Simple Infective Complication?

OBJECTIVE: To analyze the spectrum of Centers for Disease Control and Prevention (CDC)-defined pneumonia after esophageal cancer surgery. SUMMARY BACKGROUND DATA: Pneumonia is commonly documented after esophageal cancer surgery, and reducing its incidence is central to both ERAS development and to the evidence-base for minimally invasive approaches. The existing definitions of pneumonia based on hospital acquired pneumonia classifications may be suboptimal in this context and merits strict academic scrutiny. METHODS: Patients (2013-2018) treated with curative intent by open surgery were studied. Pneumonia was defined per the CDC definition. Risk factors and associations were analyzed, as was the implications of positive cultures. Multivariable logistic regression examined independently predictive factors of pneumonia and oncologic outcomes. RESULTS: Of 343 patients, 56 (16%) had defined pneumonia, 22 (39%) with positive cultures. Preoperative respiratory disease predicted pneumonia ( P = 0.043). Neoadjuvant therapy was significantly ( P = 0.004) associated with culture negative pneumonia, and age ( P = 0.001) with culture positive pneumonia. In multivariable analysis, pneumonia was associated ( P < 0.05) with respiratory comorbidity, tumor site, and neoadjuvant chemoradiation. Pneumonia did not impact on overall survival (P = 0.807). DISCUSSION: CDC-defined pneumonia occurred in 16% of cases. Culture-negative pneumonia accounted for 61% of cases and was significantly associated with neoadjuvant chemoradiation. Pneumonia as currently defined seems to represent a spectrum of etiology and severity in the post-esoph-agectomy patient, with infection per se rarely proven, suggesting a need to reevaluate its definition, severity classification, and preventive and treatment strategies.

CROSS Versus FLOT Regimens in Esophageal and Esophagogastric Junction Adenocarcinoma: A Propensity-Matched Comparison.

BACKGROUND: The FLOT protocol and the CROSS trimodality regimen represent current standards in the management of locally advanced esophageal adenocarcinoma. In the absence of published Randomised Controlled Trial data, this propensity-matched comparison evaluated tolerance, toxicity, impact on sarcopenia and pulmonary physiology, operative complications, and oncologic metrics. METHODS: Two hundred and twenty-two patients, 111 in each arm, were included from 2 high-volume centers. Computed tomography-measured sarcopenia, and pulmonary function (forced expiratory volume in first second/forced vital capacity/diffusion capacity for carbon monoxide) were compared pretherapy and posttherapy. Operative complications were defined as per the Esophageal Complications Consensus Group (ECCG) criteria, and severity per Clavien-Dindo. Tumor regression grade and R status were measured, and survival estimated per Kaplan-Meier. RESULTS: A total of 83% were male, cT3/cN+ was 92%/68% for FLOT, and 86%/60% for CROSS. The full prescribed regimen was tolerated in 40% of FLOT patients versus 92% for CROSS. Sarcopenia increased from 16% to 33% for FLOT, and 14% to 30% in CROSS ( P <0.01 between arms). Median decrease in diffusion capacity for carbon monoxide was -8.25% (-34 to 25) for FLOT, compared with -13.8%(-38 to 29), for CROSS ( P =0.01 between arms). Major pathologic response was 27% versus 44% for FLOT and CROSS, respectively ( P =0.03). In-hospital mortality, respectively, was 1% versus 2% ( P =0.9), and Clavien Dindo >III 22% versus 27% ( P =0.59), however, respiratory failure was increased by CROSS, at 13% versus 3% ( P <0.001). Three-year survival was similar at 63% (FLOT) and 60% (CROSS) ( P =0.42). CONCLUSIONS: Both CROSS and FLOT resulted in equivalent survival. Operative outcomes were similar, however, the CROSS regimen increased postoperative respiratory failure and atrial fibrillation. Less than half of patients received the prescribed FLOT regimen, although toxicity rates were acceptable. These data support clinical equipoise, caution, however, may be advised with CROSS in patients with greatest respiratory risk.

Acute Kidney Injury After Esophageal Cancer Surgery: Incidence, Risk Factors, and Impact on Oncologic Outcomes.

OBJECTIVE: To determine the incidence, risk factors, and consequences of AKI in patients undergoing surgery for esophageal cancer. SUMMARY OF BACKGROUND DATA: Esophageal cancer surgery is an exemplar of major operative trauma, with well-defined risks of respiratory, cardiac, anastomotic, and septic complications. However, there is a paucity of literature regarding AKI. METHODS: consecutive patients undergoing curative-intent surgery for esophageal cancer from 2011 to 2017 in 3 high-volume centers were studied. AKI was defined according to the AKI Network criteria. AKI occurred if, within 48 hours postoperatively, serum creatinine rose by 50% or by 0.3 mg/dL (26.5 µmol/L) from preoperative baseline. Complications were recorded prospectively. Multivariable logistic regression determined factors independently predictive of AKI. RESULTS: A total of 1135 patients (24.7%:75.3% female:male, with a mean age of 64, a baseline BMI of 27 kg m-2, and dyslipidemia in 10.2%), underwent esophageal cancer surgery, 85% having an open thoracotomy. Overall in-hospital mortality was 2.1%. Postoperative AKI was observed in 208 (18.3%) patients, with AKI Network 1, 2, and 3 in 173 (15.2%), 28 (2.5%), and 7 (0.6%), respectively. Of these, 70.3% experienced improved renal function within 48 hours. Preoperative factors independently predictive of AKI were age [P = 0.027, odds ratio (OR) 1.02 (1.00-1.04)], male sex [P = 0.015, OR 1.77 (1.10-2.81)], BMI at diagnosis [P < 0.001, OR 1.10 (1.07-1.14)], and dyslipidemia [P = 0.002, OR 2.14 (1.34-3.44)]. Postoperatively, AKI was associated with atrial fibrillation (P = 0.013) and pneumonia (P = 0.005). Postoperative AKI did not impact survival outcomes. CONCLUSION: AKI is common but mostly self-limiting after esophageal cancer surgery. It is associated with age, male sex, increased BMI, dyslipidemia, and postoperative morbidity.

C-Reactive Protein and C-Reactive Protein-Based Scores to Predict Survival in Esophageal and Junctional Adenocarcinoma: Systematic Review and Meta-Analysis.

BACKGROUND: Esophageal adenocarcinoma (EAC) has a poor prognosis; predictive markers of prognosis would facilitate advances in personalized therapy. C-reactive protein (CRP) and CRP-based scores are increasingly recommended across oncology; however, their role and value in EAC is unclear. This systematic review and meta-analysis examined CRP cut-point and scores and how they may best be applied in predicting survival in EAC. METHODS: A systematic literature search was conducted in EMBASE, Medline, Web of Science, Cochrane, Scopus and CINAHL databases, from inception to 1st October 2020. Studies reporting data from adults with EAC including adenocarcinoma of the gastro-esophageal junction (AEG), pre-treatment CRP or CRP-based score and Hazard Ratio (HR) for survival were included. QUIPS tool assessed risk of bias. Meta-analysis was undertaken. RESULTS: A total of 819 records were screened. Eight papers were included, with data for 1475 people. CRP cut-points ranged from 2.8 to 10 mg/L. The Glasgow Prognostic Score (GPS) and modified GPS were the most commonly reported scores. On meta-analysis, elevated preoperative GPS/mGPS was significantly associated with worse overall survival (hazards ratio [HR] 1.81, 95% confidence interval [CI] 1.25-2.62, p = 0.002); results were similar in subgroup analyses of multimodal treatment, M0 disease, and R0 resection. CONCLUSIONS: This is the first review to evaluate comprehensively the evidence for CRP and CRP-based scores in EAC. Meta-analysis demonstrated that elevated preoperative GPS or mGPS was significantly associated with reduced overall survival in EAC, including AEG. There is insufficient evidence to support use of CRP alone. Future studies should examine GPS/mGPS in EAC prospectively, alone and combined with other prognostic markers.

Steric Repulsion Induced Conformational Switch in Supramolecular Structures.

Inspired by the rigidified architecture of 'picket-fence' systems, we propose a strategy utilizing strain to impose intramolecular tension in already peripherally overcrowded structures leading to selective atropisomeric conversion. Employing this approach, tuneable shape-persistent porphyrin conformations were acquired exhibiting distinctive supramolecular nanostructures based on the orientation of the peripheral groups. The intrinsic assemblies driven by non-covalent bonding interactions form supramolecular polymers while encapsulating small molecules in parallel channels or solvent-accessible voids. The developed molecular strain engineering methodologies combined with synthetic approaches have allowed the introduction of the pivalate units creating a highly strained molecular skeleton. Changes in the absorption spectrum indicated the presence of severe steric repulsions between the peripheral groups which were confirmed by single crystal X-ray analysis. To release the steric strain introduced by the peripheral units, thermal equilibration strategies were used to selectively convert the most abundant atropisomer to the desirable minor one.

Interventions targeting postoperative pulmonary complications (PPCs) in patients undergoing esophageal cancer surgery: a systematic review of randomized clinical trials and narrative discussion.

Postoperative pulmonary complications (PPCs) represent the most common complications after esophageal cancer surgery. The lack of a uniform reporting nomenclature and a severity classification has hampered consistency of research in this area, including the study of interventions targeting prevention and treatment of PPCs. This systematic review focused on RCTs of clinical interventions used to minimize the impact of PPCs. Searches were conducted up to 08/02/2021 on MEDLINE (OVID), CINAHL, Embase, Web of Science, and the COCHRANE library for RCTs and reported in accordance with PRISMA guidelines. A total of 339 citations, with a pooled dataset of 1,369 patients and 14 RCTs, were included. Heterogeneity of study design and outcomes prevented meta-analysis. PPCs are multi-faceted and not fully understood with respect to etiology. The review highlights the paucity of high-quality evidence for best practice in the management of PPCs. Further research in the area of intraoperative interventions and early postoperative ERAS standards is required. A consistent uniform for definition of pneumonia after esophagectomy and the development of a severity scale appears warranted to inform further RCTs and guidelines.

Visceral obesity with and without metabolic syndrome: incidence and clinical impact in esophageal adenocarcinoma treated with curative intent.

Visceral obesity (VO) and metabolic syndrome (MetS) are risk factors for esophageal adenocarcinoma (EAC); however, their impact on operative and oncological outcomes is unclear. The aim of this study was to determine the incidence of VO and MetS among patients with EAC, and to assess their independent impact on operative and oncological outcomes. A total of 454 consecutive patients undergoing treatment with curative intent were studied. Total, subcutaneous, visceral fat area (VFA), and lean body mass (LBM) were measured by computed tomography pretreatment, with VO defined as VFA >163.8cm2 for men and 80.1cm2 for women. MetS was defined per the ATPIII definition. Multivariable logistic and Cox proportional hazards regression were utilized to determine independent predictors of oncologic and operative outcomes. A total of 227 patients (50.0%) had VO. A total of 134 (30%) overall had MetS, 44% in the VO cohort. VO was associated with Barrett's esophagus (P = 0.002) and lower cT (P = 0.006) and cN stage (P = 0.011), and improved disease-specific (P = 0.021) and overall survival (P = 0.012). No survival benefit existed for patients with VO who also had MetS. For operative complications, neither VO nor MetS increased the severity of complications, or mortality. However, VO was significantly (P = 0.035) associated with anastomotic leak and pneumonia (P = 0.037). MetS alone did not increase complication risk. VO increases specific major operative complications with no increase in mortality. VO improved survival, mainly relating to earlier stage disease; however, co-existent MetS abrogated this benefit. These seemingly paradoxical outcomes highlight manageable and potentially targetable perioperative challenges in the context of an overall favorable oncologic vista.

FLOT-regimen Chemotherapy and Transthoracic en bloc Resection for Esophageal and Junctional Adenocarcinoma.

BACKGROUND AND AIMS: The FLOT4-AIO trial established the FLOT regimen as a compelling option for gastric, junctional and esophageal adenocarcinoma. Data on FLOT with en-bloc transthoracic esophagectomy (TTE) are limited. This study explored operative complications, tolerance, toxicity, physiological impact, and oncologic outcomes. STUDY DESIGN: An observational cohort study on consecutive patients at 3 tertiary centers undergoing FLOT and TTE. Toxicity, operative complications (per ECCG definitions), tumor regression grade (TRG), recurrences and survival were documented, as well as pre and post FLOT assessment of sarcopenia and pulmonary physiology. RESULTS: 175 patients (cT2-4a, Nany) commenced treatment, 84% male, median age 65, 94% cT3/T4a, 73% cN+. 89% completed 4 preoperative cycles, and 35% all cycles. Grade 3/4 toxicities included neutropenia (12%), diarrhoea (13%), and infection (15%). Sarcopenia increased from 18% to 37% (P = 0.020), and diffusion capacity (DLCO) decreased by 8% (-34% + 25%; P < 0.010). On pathology, ypT3/4 was 59%, and ypN+54%, with 10% TRG 1, 14% TRG 2, and 76% TRG3-5, and R0 95%. 161 underwent TTE, with an in-hospital mortality of 0.6%, 24%-pneumonia, 11%-anastomotic leak, and Clavien Dindo ≥III in 27%. At a median follow up of 12 months (1-85), 33 relapsed, 8 (5%) locally, and 3yr survival was 60%. CONCLUSION: FLOT and en bloc TTE was safe, with no discernible impact on operative complications, with 24% having a major pathologic response. Caveats include a limited pathologic response in the majority, and negative impact on muscle mass and lung physiology, and low use of adjuvant cycles. These data may provide a real-world benchmark for this complex care pathway.

Management of chyle leaks following esophageal resection: a systematic review.

BACKGROUND: Chyle leakage is an uncommon but potentially life-threatening complication following esophageal resections. The optimal management strategy is not clear, with a limited evidence base. METHODS: Searches were conducted up to 31 December 2020 on MEDLINE, Embase, and Web of Science for randomized trials or retrospective studies that evaluated the management of chyle leakage following esophageal resection. Two authors independently screened studies, extracted data, and assessed for bias. The protocol was prospectively registered on PROSPERO (CRD: 42021224895) and reported in accordance with preferred reporting items for systematic reviews and meta-analyses guidelines. RESULTS: A total of 530 citations were reviewed. Twenty-five studies, totaling 1016 patients met the inclusion criteria, including two low-quality clinical trials and 23 retrospective case series. Heterogeneity of study design and outcomes prevented meta-analysis. The overall incidence of chyle leak/fistula was 3.2%. Eighteen studies describe management of chyle leaks conservatively, 17 by surgical ligation of the thoracic duct, 5 by pleurodesis, and 6 described percutaneous lymphangiography with thoracic duct embolization or disruption. CONCLUSIONS: The evidence base for optimal management of chyle leakage postesophagectomy is lacking, which may be related to its low incidence. There is a paucity of high-quality prospective studies directly comparing treatment modalities, but there is some low-certainty evidence that percutaneous approaches have reduced morbidity but lower efficacy compared with surgery. Further high-quality, prospective studies that compare interventions at different levels of severity are needed to determine the optimal approach to treatment.