Oligomerization-driven avidity correlates with SARS-CoV-2 cellular binding and inhibition.

Cellular processes are controlled by the thermodynamics of the underlying biomolecular interactions. Frequently, structural investigations use one monomeric binding partner, while ensemble measurements of binding affinities generally yield one affinity representative of a 1:1 interaction, despite the majority of the proteome consisting of oligomeric proteins. For example, viral entry and inhibition in SARS-CoV-2 involve a trimeric spike surface protein, a dimeric angiotensin-converting enzyme 2 (ACE2) cell-surface receptor and dimeric antibodies. Here, we reveal that cooperativity correlates with infectivity and inhibition as opposed to 1:1 binding strength. We show that ACE2 oligomerizes spike more strongly for more infectious variants, while exhibiting weaker 1:1 affinity. Furthermore, we find that antibodies use induced oligomerization both as a primary inhibition mechanism and to enhance the effects of receptor-site blocking. Our results suggest that naive affinity measurements are poor predictors of potency, and introduce an antibody-based inhibition mechanism for oligomeric targets. More generally, they point toward a much broader role of induced oligomerization in controlling biomolecular interactions.

An ultra-stable gold-coordinated protein cage displaying reversible assembly.

Symmetrical protein cages have evolved to fulfil diverse roles in nature, including compartmentalization and cargo delivery1, and have inspired synthetic biologists to create novel protein assemblies via the precise manipulation of protein-protein interfaces. Despite the impressive array of protein cages produced in the laboratory, the design of inducible assemblies remains challenging2,3. Here we demonstrate an ultra-stable artificial protein cage, the assembly and disassembly of which can be controlled by metal coordination at the protein-protein interfaces. The addition of a gold (I)-triphenylphosphine compound to a cysteine-substituted, 11-mer protein ring triggers supramolecular self-assembly, which generates monodisperse cage structures with masses greater than 2 MDa. The geometry of these structures is based on the Archimedean snub cube and is, to our knowledge, unprecedented. Cryo-electron microscopy confirms that the assemblies are held together by 120 S-Aui-S staples between the protein oligomers, and exist in two chiral forms. The cage shows extreme chemical and thermal stability, yet it readily disassembles upon exposure to reducing agents. As well as gold, mercury(II) is also found to enable formation of the protein cage. This work establishes an approach for linking protein components into robust, higher-order structures, and expands the design space available for supramolecular assemblies to include previously unexplored geometries.

Validation and Optimisation of the ISGPS Risk Classification for Postoperative Pancreatic Fistula after Pancreatoduodenectomy for Periampullary Tumours.

OBJECTIVES: To externally validate the International Study Group of Pancreatic Surgery (ISGPS) classification and test its performance for predicting clinically relevant pancreatic fistula (CRPF) for periampullary tumours (P-amps). BACKGROUND: The ISGPS is a simple two-factor, four-tier classification of pancreas-related risk for CRPF after a pancreatoduodenectomy (PD). External validation and performance of the classification specific to P-amps are lacking. P-amps have different disease biology, lesser need for neoadjuvant therapy, softer pancreas, and a higher rate of CRPF, underscoring the importance of site-specific prediction. METHODS: Validation was performed in a cohort of 1422 patients, with CRPF as the primary outcome. Model performance was tested by plotting the receiver operating curve and calibration plots. After analysing the factors predicting CRPF, the model was optimised for P-amps. RESULTS: CRPF rate was 22.2% (315/1422), for P-amps being 25.8%. The ISGPS model performed moderately (AUC=0.632, 95% CI 0.598-0.666, P<0.001), with worse performance for P-amps (AUC=0.605, 95% CI 0.566-0.645, P<0.001). On multivariate analysis, soft pancreas (OR 1.689, 95% CI 1.136-2.512, P=0.010), body mass index ≥23 kg/m2 (OR 2.112, 95% CI 1.464-3.046, P<0.001) and pancreatic duct ≤3 mm (OR 2.113 95% CI 1.457-3.064, P<0.001), emerged as independent predictors and the model was optimised. The adjusted ISGPS for P-amps showed improved discrimination (AUC=0.672, P<0.001, 95% CI 0.637-0.707), with adequate performance on internal validation. CONCLUSION: The adjusted ISPGS performs better than the original ISGPS in predicting CRPF for P-amps. Large-scale multicenter data is needed to generate and validate site-specific predictive models.

CA 19-9 Surveillance Detects Recurrences Early and Contributes to Improvement in Survival in Resected Ampullary Cancers: Analysis of 572 cases.

OBJECTIVE: To determine the clinical utility of serum CA 19-9 surveillance for detecting recurrences in resected ampullary carcinomas (ACs). INTRODUCTION: Although an established prognostic marker for pancreatic ductal adenocarcinoma, the value of CA 19-9 in resected ACs during follow-up is unknown. METHODS: Retrospective analysis of ACs undergoing pancreaticoduodenectomy at Tata Memorial Centre-Mumbai, from January 2012 to January 2020 was performed. Survival, recurrence patterns, factors associated with recurrences and the utility of CA 19-9 surveillance were assessed. RESULTS: The 5-year OS of 572 included patients with ACs, was 56.4%. There were 251(43.88%) recurrences, majority being distant (n=223). Higher 'T' & 'N' stage, margin involvement, perineural invasion, poor tumour differentiation and pancreatobiliary subtype were associated with poor outcomes. Optimal CA 19-9 level to predict recurrence was 77.85 U/mL (sensitivity-61.22%, specificity-76.67%, AUC-0.711); however, a serial rise was a more accurate predictor (sensitivity-71.05%, specificity-91.67%). The median duration between the first rise in CA 19-9 (>37 U/mL) and radiological evidence of recurrence was 4.04 months. The optimal level of relative rise in CA 19-9 in diagnosing a recurrence was established at 2.79x (sensitivity-46.26%, specificity-83.33%, AUC-0.614). A serial rise and absolute value of >200 U/mL was associated with recurrence in 87% & 92.9% of cases. Recurrence detection & treatment after serum CA 19-9 elevation was associated with superior median survival as compared to recurrence detection without elevation (12.8 mo vs. 7.6 mo, P=0.005). CONCLUSION: Serum CA 19-9 testing during follow-up evaluation detects recurrences early and improves survival in resected ACs, and therefore should be recommended as a routine surveillance test.

Mass photometry enables label-free tracking and mass measurement of single proteins on lipid bilayers.

The quantification of membrane-associated biomolecular interactions is crucial to our understanding of various cellular processes. State-of-the-art single-molecule approaches rely largely on the addition of fluorescent labels, which complicates the quantification of the involved stoichiometries and dynamics because of low temporal resolution and the inherent limitations associated with labeling efficiency, photoblinking and photobleaching. Here, we demonstrate dynamic mass photometry, a method for label-free imaging, tracking and mass measurement of individual membrane-associated proteins diffusing on supported lipid bilayers. Application of this method to the membrane remodeling GTPase, dynamin-1, reveals heterogeneous mixtures of dimer-based oligomers, oligomer-dependent mobilities, membrane affinities and (dis)association of individual complexes. These capabilities, together with assay-based advances for studying integral membrane proteins, will enable the elucidation of biomolecular mechanisms in and on lipid bilayers.

Robotic Pancreaticoduodenectomy with 'SMA-First Approach (Posterior and Right Medial)' and 'Triangle Operation'.

BACKGROUND: Notable improvements in pancreatic cancer surgery have been due to utilization of the superior mesenteric artery (SMA)-first approach1 and triangle operation (clearance of triangle tissue between origin of SMA and celiac artery).2 The SMA-first approach was originally defined to assess resectability before taking the irreversible surgical steps. However, in the present era, resectability is judged by the preoperative radiology, and the benefit of the SMA-first approach is by improving the R0 resection rate and reducing blood loss. The basic principle is to identify the SMA at its origin and in the distal part, to guide the plane of uncinate dissection. This video demonstrates the combination of the posterior and right medial SMA-first approach along with triangle clearance during robotic pancreaticoduodenectomy (RPD). METHODS: The technique consisted of early dissection of SMA from the posterior aspect, by performing a Kocher maneuver using the 'posterior SMA-first approach'. The origin of the celiac artery, along with the SMA, was defined early in the surgery. During uncinate process dissection, the 'right/medial uncinate approach' was used to approach the SMA. 'Level 3 systematic mesopancreatic dissection' was performed along the SMA,3 culminating in the 'triangle operation'.2 RESULTS: The procedure was performed within 600 min, with a blood loss of 150 mL and no intraoperative or postoperative complications. The final histopathology report showed a moderately differentiated adenocarcinoma (pT2, pN2), with all resection margins free. CONCLUSION: The standardized technique of the SMA-first approach and triangle clearance during RPD is demonstrated in the video. Prospective studies should further evaluate the benefits of this procedure.

1657 Resected Gastric Adenocarcinomas at a Single Institution: Outcomes and Trends over 17 Years.

BACKGROUND: Outside of clinical trials, real-world data of advanced gastric cancers (AGCs) managed with perioperative or adjuvant chemotherapy with a backbone of D2 lymphadenectomy is limited. PATIENTS AND METHODS: Curative resections for gastric adenocarcinoma between January 2003 and January 2020 at the Tata Memorial Centre were analyzed, comparing three time periods marking major increments in annual gastric resections (GRs). RESULTS: 1657 radical gastric resections were performed with a morbidity and mortality rate of 34.9% and 1.4%, respectively. Over three consecutive periods, the number of annual GRs increased from 56/year to 97/year to 156/year (P < 0.001) with a significant escalation in surgical magnitude and complexity. Improvement in surgical quality indicators (median lymph node yield from 15 to 25, P < 0.001 and margin negativity from 8.2 to 5.5%, P = 0.002) was observed with no corresponding increase in severe complications (6.9%) or mortality (1.4%). The proportion of distal and signet ring cancers was found to decrease over time, with an increase in proximal cancers and younger age at presentation. Overall, 90% of GRs were for AGCs with a median overall survival (OS) of 4.4 years (± 6 months), and 5-year OS rate of 47.6% (± 1.9%). CONCLUSIONS: Change in pattern of tumor characteristics was observed. Aggressive treatment options for AGC were employed progressively with excellent survival. With increase in volumes, improvements in surgical quality indicators, and a relative improvement in postoperative mortality was observed. These results provide a roadmap for developing dedicated gastric cancer centers.

Ovarian Cancer Ascites Inhibits Transcriptional Activation of NK Cells Partly through CA125.

Malignant ascites is a common clinical problem in ovarian cancer. NK cells are present in the ascites, but their antitumor activity is inhibited. The underlying mechanisms of the inhibition have yet to be fully elucidated. Using an Fcγ receptor-mediated NK cell activation assay, we show that ascites from ovarian cancer patients potently inhibits NK cell activation. Part of the inhibitory activity is mediated by CA125, a mucin 16 fragment shed from ovarian cancer tumors. Moreover, transcriptional analyses by RNA sequencing reveal upregulation of genes involved in multiple metabolic pathways but downregulation of genes involved in cytotoxicity and signaling pathways in NK cells purified from ovarian cancer patient ascites. Transcription of genes involved in cytotoxicity pathways are also downregulated in NK cells from healthy donors after in vitro treatment with ascites or with a CA125-enriched protein fraction. These results show that ascites and CA125 inhibit antitumor activity of NK cells at transcriptional levels by suppressing expression of genes involved in NK cell activation and cytotoxicity. Our findings shed light on the molecular mechanisms by which ascites inhibits the activity of NK cells and suggest possible approaches to reactivate NK cells for ovarian cancer immunotherapy.

Central versus distal pancreatectomy for low-grade and benign pancreatic neck-body tumours.

PURPOSE: Central pancreatectomy (CP) offers parenchymal preservation compared to conventional distal pancreato-splenectomy for pancreatic neck and body tumours. However, it is associated with more morbidity. This study is aimed at evaluating the peri-operative and long-term functional outcomes, comparing central and distal pancreatectomies (DPs). METHODS: Retrospective analysis of patients undergoing pancreatic resections for low-grade malignant or benign tumours in pancreatic neck and body was performed (from January 2007 to December 2022). Preoperative imaging was reviewed for all cases, and only patients with uninvolved pancreatic tail, whereby a CP was feasible, were included. Peri-operative outcomes and long-term functional outcomes were compared between CP and DP. RESULTS: One hundred twenty-two (5.2%) patients, amongst the total of 2304 pancreatic resections, underwent central or distal pancreatectomy for low-grade malignant or benign tumours. CP was feasible in 55 cases, of which 23 (42%) actually underwent CP and the remaining 32 (58%) underwent DP. CP group had a significantly longer operative time [370 min (IQR 300-480) versus 300 min (IQR 240-360); p = 0.002]; however, the major morbidity (43.5% versus 37.5%; p = 0.655) and median hospital stay (10 versus 11 days; p = 0.312) were comparable. The long-term endocrine functional outcome was favourable for the CP group [endocrine insufficiency rate was 13.6% in central versus 42.8% in distal (p = 0.046)]. CONCLUSION: Central pancreatectomy offers better long-term endocrine function without any increased morbidity in low malignant potential or benign pancreatic tumours of neck and body region.

Arsenic Stress Mitigation Using a Novel Plant Growth-Promoting Bacterial Strain Bacillus mycoides NR5 in Spinach Plant (Spinacia oleracea L.).

Present study aimed to identify arsenic (As)-resistant bacterial strains that can be used to mitigate arsenic stress. A bacterium Bacillus mycoides NR5 having As tolerance limit of 1100 mg L-1 was isolated from Nag River, Maharashtra, India. It was also equipped with plant growth-promoting (PGP) attributes like phosphate solubilization, siderophores, ammonia, and nitrate reduction, with added antibiotic tolerance. Furthermore, scanning electron microscopy (SEM) and transmission electron micrograph (TEM) suggested biosorption as possible mechanisms of arsenic tolerance. A strong peak in FTIR spectra at 3379.0 corresponding to amine in As-treated NR5 also indicated metal interaction with cell surface protein. Amplification of arsenic reductase gene in NR5 further suggested intracellular transformation of As speciation. Moreover, As tolerance capability of NR5 was shown in spinach plants in which the bacterium effectively mitigated 25 ppm As by producing defense-related proline molecules. Evidence from SEM, TEM, and FTIR, concluded biosorption possibly the primary mechanism of As tolerance in NR5 along with the transformation of arsenic. B. mycoides NR5 with PGP attributes, high As tolerance, and antibiotic resistance mediated enhanced As tolerance in spinach plants advocated that the strain can be a better choice for As bioremediation in contaminated agricultural soil and water.

Differential impact of incrementally elevated CA 19-9 levels on prognosis of resected pancreatic ductal adenocarcinoma.

BACKGROUND: CA 19-9 is an extremely useful biomarker for pancreatic ductal adenocarcinomas (PDACs). However, the optimal cut-off and prognostic significance at higher cut-offs are yet to be determined. METHODS: Retrospective analysis included patients with PDAC who underwent curative resection from January 2010 to May 2020 at Tata Memorial Centre, Mumbai. The pretherapy CA 19-9 was dichotomized using various cut-off levels and analysed. RESULTS: In 244 included patients, the median overall survival (OS) for those with CA19-9 level (IU/ml) < or >78, 200, 500, 1000, and 2000 was 27, 24, 23, 22, 21 months versus 18, 16, 15, 14, 13 months; respectively, and was statistically significant (p-value- 0.002, 0.001, 0.002, 0.002 and 0.004, respectively). The number of recurrences and mortality had significant correlation with CA 19-9 cut-offs. On multivariate analysis, adjuvant treatment completion (p-0.004) and decreasing or stable CA19-9 after Neoadjuvant therapy (NAT) (p- 0.031) were associated with improved OS. CONCLUSION: The prognostic significance of CA 19-9 was observed at all the cut-off levels examined, beyond mere elevated value as per the standard cut-off level. In patients with high CA19-9 level, surgery should be offered if technically and conditionally feasible, only when a response in CA19-9 level to NAT is achieved.

6-Plex mdSUGAR Isobaric-Labeling Guide Fingerprint Embedding for Glycomics Analysis.

Glycans are vital biomolecules with diverse functions in biological processes. Mass spectrometry (MS) has become the most widely employed technology for glycomics studies. However, in the traditional data-dependent acquisition mode, only a subset of the abundant ions during MS1 scans are isolated and fragmented in subsequent MS2 events, which reduces reproducibility and prevents the measurement of low-abundance glycan species. Here, we reported a new method termed 6-plex mdSUGAR isobaric-labeling guide fingerprint embedding (MAGNI), to achieve multiplexed, quantitative, and targeted glycan analysis. The glycan peak signature was embedded by a triplicate-labeling strategy with a 6-plex mdSUGAR tag, and using ultrahigh-resolution mass spectrometers, the low-abundance glycans that carry the mass fingerprints can be recognized on the MS1 spectra through an in-house developed software tool, MAGNIFinder. These embedded unique fingerprints can guide the selection and fragmentation of targeted precursor ions and further provide rich information on glycan structures. Quantitative analysis of two standard glycoproteins demonstrated the accuracy and precision of MAGNI. Using this approach, we identified 304 N-glycans in two ovarian cancer cell lines. Among them, 65 unique N-glycans were found differentially expressed, which indicates a distinct glycosylation pattern for each cell line. Remarkably, 31 N-glycans can be quantified in only 1 × 103 cells, demonstrating the high sensitivity of our method. Taken together, our MAGNI method offers a useful tool for low-abundance N-glycan characterization and is capable of determining small quantitative differences in N-glycan profiling. Therefore, it will be beneficial to the field of glycobiology and will expand our understanding of glycosylation.

Pancreaticoduodenectomy in the Portal Annular Pancreas-Mesopancreas Triangle Approach (with Video).

BACKGROUND: Portal Annular Pancreas (PAP) is a relatively uncommon entity with 4% reported incidence. Pancreaticoduodenectomy is challenging in cases with PAP and is associated with higher postoperative pancreatic fistula rate and overall morbidity. PAP is classified according to the pattern and location of fusion around the portal vein as-supra-splenic, infra-splenic & mixed fusion type. Also, the ductal anatomy can vary as pancreatic duct present only in the ante-portal portion or only in the retro-portal portion or ducts in both ante and retro-portal portion. At present, ideal surgical strategy is not defined as per the PAP types. METHODS: The case demonstrated in the video presented with a localized, large duodenal mass with type IIA PAP (supra-splenic fusion with both ante and retro-portal ducts) detected on the preoperative triphasic CT scan. To achieve a single pancreatic cut surface with a single pancreatic duct for anastomosis, an extended pancreatic resection was performed using meso-pancreas triangle approach. RESULTS: Patient had a smooth intraoperative course & the postoperative recovery was also uneventful. Pathology reported pT3 duodenal cancer with negative margins and uninvolved lymph nodes. CONCLUSION: A preoperative knowledge of PAP and its various types is extremely important in order to tailor intraoperative management, specially of the retro-portal portion. In patients with retro-portal duct or both ante and retro-portal ducts (as the case presented in the video), an extended resection is recommended to mitigate postoperative pancreatic fistula.

Oxidative phosphorylation inhibitors inhibit proliferation of endometriosis cells.

In brief: Developing novel therapies to cure and manage endometriosis is a major unmet need that will benefit over 180 million women worldwide. Results from the current study suggest that inhibitors of oxidative phosphorylation may serve as novel agents for the treatment of endometriosis. Abstract: Current therapeutic strategies for endometriosis focus on symptom management and are not curative. Here, we provide evidence supporting the inhibition of oxidative phosphorylation (OXPHOS) as a novel treatment strategy for endometriosis. Additionally, we report an organotypic organ-on-a-chip luminal model for endometriosis. The OXPHOS inhibitors, curcumin, plumbagin, and the FDA-approved anti-malarial agent, atovaquone, were tested against the endometriosis cell line, 12Z, in conventional as well as the new organotypic model. The results suggest that all three compounds inhibit proliferation and cause cell death of the endometriotic cells by inhibiting OXPHOS and causing an increase in intracellular oxygen radicals. The oxidative stress mediated by curcumin, plumbagin, and atovaquone causes DNA double-strand breaks as indicated by the elevation of phospho-γH2Ax. Mitochondrial energetics shows a significant decrease in oxygen consumption in 12Z cells. These experiments also highlight differences in the mechanism of action as curcumin and plumbagin inhibit complex I whereas atovaquone blocks complexes I, II, and III. Real-time assessment of cells in the lumen model showed inhibition of migration in response to the test compounds. Additionally, using two-photon lifetime imaging, we demonstrate that the 12Z cells in the lumen show decreased redox ratio (NAD(P)H/FAD) and lower fluorescence lifetime of NAD(P)H in the treated cells confirming major metabolic changes in response to inhibition of mitochondrial electron transport. The robust chemotoxic responses observed with atovaquone suggest that this anti-malarial agent may be repurposed for the effective treatment of endometriosis.

Big data and RCT's in surgical oncology: Impact on improving hepatopancreatobiliary cancer surgical care on the global stage.

Randomized controlled clinical trials (RCTs) are at the heart of "evidence-based" medicine. Conducting well-designed RCTs for surgical procedures is often challenged by inadequate recruitment accrual, blinding, or standardization of the surgical procedure, as well as lack of funding and evolution of the treatment strategy during the many years over which such trials are conducted. In addition, most clinical trials are performed in academic high-volume centers with highly selected patients, which may not necessarily reflect a "real-world" practice setting. Large databases provide easy and inexpensive access to data on a large and diverse patient population at a variety of treatment centers. Furthermore, large database studies provide the opportunity to answer questions that would be impossible or very arduous to answer using RCTs, including questions regarding health policy efficacy, trends in surgical practice, access to health care, the impact of hospital volume, and adherence to practice guidelines, as well as research questions regarding rare disease, infrequent surgical outcomes, and specific subpopulations. Prospective data registries may also allow for quality benchmarking and auditing. There are several high-quality RCTs providing evidence to support current practices in hepatopancreatobiliary (HPB) oncology. Evidence from big data bridges the gap in several instances where RCTs are lacking. In this article, we review the evidence from RCTs and big data in HPB oncology identify the existing lacunae, and discuss the future directions of research in HPB oncology.

Prognostic predictors for recurrence following curative resection in grade I/II pancreatic neuroendocrine tumours.

INTRODUCTION: Pancreatic neuroendocrine tumours (pNETs) have an excellent long-term survival after resection, but are associated with a high recurrence rate. Identification of prognostic factors affecting recurrences would enable identifying subgroup of patients at higher risk of recurrences, who may benefit from more aggressive treatment. METHODS: A retrospective analysis of prospectively maintained database of patients undergoing pancreatectomy with curative intent for grade I and II pNETs between July 2007 and June 2021 was performed. Perioperative and long-term outcomes were analysed. RESULTS: A total of 68 resected patients of pNETs were included in this analysis. Fifty-two patients (76.47%) underwent pancreaticoduodenectomy, 10 (14.7%) patients had distal pancreatectomy, and 2 (2.9%) patients underwent median pancreatectomy, while enucleation was performed in 4 patients (5.8%). The overall major morbidity (Clavien-Dindo III/IV) and mortality rates were 33.82% and 2.94%, respectively. At a median follow-up period of 48 months, 22 (32.35%) patients had disease recurrence. The 5-year overall survival and 5-year recurrence-free survival (RFS) rates were 90.2% and 60.8%, respectively. While OS was unaffected by different prognostic factors, multivariate analysis showed that lymph node involvement, Ki-67 index ≥5%, and presence of perineural invasion (PNI) were independently associated with recurrence. CONCLUSIONS: While surgical resection gives excellent overall survival in grade I/II pNETs, lymph node positivity, higher Ki-67 index, and PNI are associated with a high risk for recurrence. Patients with these characteristics should be stratified as high risk and evaluated for more intensive follow-up and aggressive treatment strategies in future prospective studies.

Pathological N3 Stage (pN3/ypN3) Gastric Cancer: Outcomes, Prognostic Factors and Pattern of Recurrences After Curative Treatment.

BACKGROUND: pN3 or ypN3 stage gastric cancers (GCs) are known to have aggressive clinical behaviour. This study aimed to investigate factors affecting survival and pattern of recurrences of N3 stage GCs, treated with curative intent. METHODS: A total of 196 GC patients, operated on at the Tata Memorial Centre from 2003 to 2017 and reported as pN3 or ypN3 status on histopathology after D2 gastrectomy were included in this retrospective analysis. RESULTS: On multivariate analysis, use of NACT (neoadjuvant chemotherapy) and LN ratio (≤ 0.5/> 0.5) emerged as significant predictors for long-term survival. Patients who received NACT but were still harbouring N3 nodes (ypN3; n = 102) had a worse prognosis than those operated on upfront (pN3; n = 94), with a median survival of 19 months versus 24 months respectively (p = 0.003). The 5-year overall survival of the entire cohort was 16.3% (95% CI 12.8-19.8%), while 5-year disease-free survival (DFS) was 14.6% (95% CI 12.6-20%). Adjuvant chemoradiotherapy, though offered in a small number of patients (n = 38) resulted in improvement in DFS. Median DFS of adjuvant CT versus adjuvant CRT was 13 months versus 23 months (p = 0.020). The commonest site of relapse was the peritoneum (49.18%) and incidence of isolated loco-regional failure was 10.7%. CONCLUSION: In GCs with N3 stage determined after radical D2 gastrectomy, LN ratio of > 0.5 and ypN3 status are predictors of poor prognosis. Considering the high incidence of peritoneal and loco-regional relapse in these patients, the role of more radical surgery, adjuvant chemoradiotherapy after upfront resection and intraperitoneal chemotherapy should be evaluated in prospective randomized clinical trials.

Organ preserving pancreatic resections offer better long-term conservation of pancreatic function at the expense of high perioperative major morbidity: a fair trade-off for benign or low malignant potential pancreatic neoplasms-a single-center experience.

BACKGROUND: Standard pancreatic resections (SPRs) might have long-term deleterious effects on pancreatic function, without added oncological advantage in low malignant potential (LMP) or benign neoplasms. This study aimed to evaluate outcomes following organ-preserving pancreatic resections (OPPARs) and SPRs. METHOD: Post hoc analysis of patients undergoing OPPAR or SPR for benign or LMP pancreatic tumors from January 2011 to January 2020 at Tata Memorial Hospital, Mumbai. RESULTS: Thirty-six and 114 patients were identified in OPPAR and SPR groups respectively. The overall morbidity (58.3% vs 43.9%, p-0.129) was comparable. Major morbidity (41.7% vs 21.9%, p-0.020), post-operative pancreatic fistula (POPF) (63.9% vs 35.1%, p-0.002), and clinically relevant POPF (41.7% vs 20.2%, p-0.010) were significantly higher with OPPAR. Post-operative endocrine insufficiency (14.9% vs 11.1%, p-0.567), exocrine insufficiency (19.3% vs 0%, p-0.004), and requirement of long-term pancreatic enzyme replacement (17.5% vs 0%, p-0.007) were higher in SPRs. Comparing left-sided and right-sided resections in the entire cohort, incidence of endocrine insufficiency was 17.1% vs 11.2% (p-0.299) and that of exocrine insufficiency was 8.6% vs 20% (p-0.048) respectively. CONCLUSION: OPPAR is associated with high post-operative major morbidity and pancreatic fistula rate but offers long-term benefit due to better preservation of pancreatic function than SPR. The incidence of exocrine insufficiency is higher in right sided as compared to left-sided pancreatic resections.

Smoking Cessation.

Tobacco smoking is the leading cause of preventable death in the United States, and its harms are well established. Physicians have more evidence-based resources than ever before to effectively treat smoking, including new uses and combinations of U.S. Food and Drug Administration-approved pharmacotherapies and expanded community programs. In addition, electronic nicotine delivery systems are potential treatment tools, but their safety and efficacy need to be established. Finally, high-priority groups, such as persons with cancer diagnoses or hospitalized patients, may benefit from particular attention to their tobacco use.

Capecitabine-Temozolomide in Advanced Grade 2 and Grade 3 Neuroendocrine Neoplasms: Benefits of Chemotherapy in Neuroendocrine Neoplasms with Significant 18FDG Uptake.

INTRODUCTION: Capecitabine-temozolomide (CAPTEM) chemotherapy, alone or with concurrent peptide receptor radionuclide therapy (PRRT), has activity in advanced WHO grade 2 and grade 3 neuroendocrine neoplasms (NENs). The objective of this study was to evaluate the activity of the CAPTEM in patients with grade 2 and grade 3 NENs and identify prognostic factors. MATERIALS AND METHODS: A retrospective analysis of patients with metastatic grade 2 and grade 3 NENs, who were having baseline significant dual uptake on 68Ga-DOTATATE/18F-fluorodeoxyglucose (FDG)-PET-CT scan and treated with CAPTEM chemotherapy between January 2014 and December 2019 at Tata Memorial Hospital, was conducted. The clinical variables and survival data were collected. Progression-free survival (PFS) was estimated using the Kaplan-Meier method. RESULTS: A total of 68 patients received the CAPTEM regimen, of whom 29 patients (43%) received CAPTEM alone and 39 patients (57%) received concurrent PRRT. The primary sites were pancreas in 32 (47%) and small intestine in 12 (18%) patients. Mean Ki-67 index was 12.6% (range: 3-50). Forty-five patients (65%) were treatment naïve. There were no significant differences in baseline clinical variables between patients treated with CAPTEM alone or with CAPTEM-PRRT. Both regimens were well tolerated. With a median follow-up of 22.1 months, the median PFS for the entire cohort was 27.5 months. There was no statistical difference in the median PFS between patients receiving CAPTEM alone or CAPTEM-PRRT (33.7 vs. 22 months; p = 0.199). A Ki-67 index of >5% predicted for inferior PFS on multivariate analysis (24 versus 73.8 months; p = 0.04; hazard ratio -3.77; 95% confidence interval: 1.07-13.26). CONCLUSION: CAPTEM, alone or concurrent with PRRT, has a significant activity in grade 2 and grade 3 NENs with dual SSTR and 18FDG expression. A Ki-67 index >5% predicts strongly for inferior outcomes and should be further explored as a prognostic cutoff in grade 2 NENs. Early initiation of CAPTEM should be considered in this group of tumors with significant baseline 18FDG expression.