Reconstruction Techniques and Associated Morbidity in Minimally Invasive Gastrectomy for Cancer - Insights from the GastroBenchmark and GASTRODATA databases.

OBJECTIVE/BACKGROUND: Various anastomotic and reconstruction techniques are used for minimally invasive total (miTG) and distal gastrectomy (miDG). Their effects on postoperative morbidity have not been extensively studied. METHODS: MiTG and miDG patients were selected from 9356 oncological gastrectomies performed 2017-2021 in 44 centers. Endpoints included anastomotic leakage (AL) rate and postoperative morbidity tested by multivariable analysis. RESULTS: Three major anastomotic techniques (circular stapled (CS); linear stapled (LS); hand sewn (HS)), and three major bowel reconstruction types (Roux (RX); Billroth I (BI); Billroth II (BII)) were identified in miTG (n=878) and miDG (n=3334). Postoperative complications including AL (5.2% vs. 1.1%), overall (28.7% vs. 16.3%) and major morbidity (15.7% vs. 8.2%), as well as 90-day mortality (1.6% vs. 0.5%) were higher after miTG compared with miDG. After miTG, AL rate was higher after CS (4.3%) and HS (7.9%) compared with LS (3.4%). Similarly, major complications (LS: 9.7%, CS: 16.2%, HS: 12.7%) were lowest after LS. Multivariate analysis confirmed anastomotic technique as predictive factor for AL, overall and major complications. In miDG, AL rate (BI: 1.4%, BII 0.8%, RX 1.2%), overall (BI: 14.5%, BII: 15.0%, RX: 18.7%,) and major morbidity (BI: 7.9%, BII: 9.1%, RX: 7.2%), and mortality (BI: 0%, BII: 0.1%, RY: 1.1%%) were not affected by bowel reconstruction. CONCLUSION: In oncologically suitable situations, miDG should be preferred to miTG, as postoperative morbidity is significantly lower. LS should be a preferred anastomotic technique for miTG in Western Centers. Conversely, bowel reconstruction in DG may be chosen according to surgeon's preference.

FOLFIRINOX or Gemcitabine-based Chemotherapy for Borderline Resectable and Locally Advanced Pancreatic Cancer: A Multi-institutional, Patient-Level, Meta-analysis and Systematic Review.

BACKGROUND: Pancreatic cancer often presents as locally advanced (LAPC) or borderline resectable (BRPC). Neoadjuvant systemic therapy is recommended as initial treatment. It is currently unclear what chemotherapy should be preferred for patients with BRPC or LAPC. METHODS: We performed a systematic review and multi-institutional meta-analysis of patient-level data regarding the use of initial systemic therapy for BRPC and LAPC. Outcomes were reported separately for tumor entity and by chemotherapy regimen including FOLFIRINOX (FIO) or gemcitabine-based. RESULTS: A total of 23 studies comprising 2930 patients were analyzed for overall survival (OS) calculated from the beginning of systemic treatment. OS for patients with BRPC was 22.0 months with FIO, 16.9 months with gemcitabine/nab-paclitaxel (Gem/nab), 21.6 months with gemcitabine/cisplatin or oxaliplatin or docetaxel or capecitabine (GemX), and 10 months with gemcitabine monotherapy (Gem-mono) (p < 0.0001). In patients with LAPC, OS also was higher with FIO (17.1 months) compared with Gem/nab (12.5 months), GemX (12.3 months), and Gem-mono (9.4 months; p < 0.0001). This difference was driven by the patients who did not undergo surgery, where FIO was superior to other regimens. The resection rates for patients with BRPC were 0.55 for gemcitabine-based chemotherapy and 0.53 with FIO. In patients with LAPC, resection rates were 0.19 with Gemcitabine and 0.28 with FIO. In resected patients, OS for patients with BRPC was 32.9 months with FIO and not different compared to Gem/nab, (28.6 months, p = 0.285), GemX (38.8 months, p = 0.1), or Gem-mono (23.1 months, p = 0.083). A similar trend was observed in resected patients converted from LAPC. CONCLUSIONS: In patients with BRPC or LAPC, primary treatment with FOLFIRINOX compared with Gemcitabine-based chemotherapy appears to provide a survival benefit for patients that are ultimately unresectable. For patients that undergo surgical resection, outcomes are similar between GEM+ and FOLFIRINOX when delivered in the neoadjuvant setting.

Synthesis of coagulation factors during long-term ex situ liver perfusion.

Robust viability assessment of grafts during normothermic liver perfusion is a prerequisite for organ use. Coagulation parameters are used commonly for liver assessment in patients. However, they are not yet included in viability assessment during ex situ perfusion. In this study, we analysed coagulation parameters during one week ex situ perfusion at 34℃. Eight discarded human livers were perfused with blood-based, heparinised perfusate for one week; perfusions in a further four livers were terminated on day 4 due to massive ongoing cell death. Coagulation parameters were well below the physiologic range at perfusion start. Physiologic levels were achieved within the first two perfusion days for factor V (68.5 ± 35.5%), factor VII (83.5 ± 26.2%), fibrinogen (2.1 ± 0.4 g/L) and antithrombin (107 ± 26.5%) in the livers perfused for one week. Despite the increased production of coagulation factors, INR was detectable only at 24h of perfusion (2.1 ± 0.3) and prolonged thereafter (INR > 9). The prolongation of INR was related to the high heparin level in the perfusate (anti-FXa > 3 U/mL). Intriguingly, livers with ongoing massive cell death also disclosed synthesis of factor V and improved INR. In summary, perfused livers were able to produce coagulation factors at a physiological level ex situ. We propose that single coagulation factor analysis is more reliable for assessing the synthetic function of perfused livers as compared to INR when using a heparinised perfusate.

Trends in pancreatic surgery in Switzerland: a survey and nationwide analysis over two decades.

BACKGROUND: Centralisation of highly specialised medicine (HSM) has changed practice and outcome in pancreatic surgery (PS) also in Switzerland. Fewer hospitals are allowed to perform pancreatic surgery according to nationally defined cut-offs. OBJECTIVE: We aimed to examine trends in PS in Switzerland. First, to assess opinions and expected trends among Swiss pancreatic surgeons in regard of PS practice and second, to assess the evolution of PS performance in Switzerland by a nationwide retrospective analysis. METHODS: First, a 26-item survey among all surgeons who performed PS in 2016 in Switzerland was performed. Then, nationwide data from 1998 to 2018 from all hospitals performing PS was analysed including centre volume, perioperative morbidity and mortality, surgical indications and utilisation of minimally invasive pancreatic surgery (MIPS). The national cut-off for regulatory accredited volume centres (AVC) was ≥ 12. Additionally, an international benchmark definition for high volume (≥ 20 surgeries/year) was used. RESULTS: Among 25 surgeons from 15 centres (response rate 51%), the survey revealed agreement that centralisation is important to improve perioperative outcomes. Respondents agreed on a minimum case load per surgeon or centre. Within the nationwide database, 8534 pancreatic resections were identified. Most resections were performed for pancreatic ductal adenocarcinoma (58.9%). There was a significant trend towards centralisation of PS with fewer non-accredited volume centres (nAVC) (36 in 1998 and 17 in 2018, p < 0.001) and more AVC (2 in 1998 and 18 in 2018, p < 0.001). A significantly higher adjusted mortality after pancreatoduodenectomy (PD) was observed in low-volume compared to high-volume hospitals (OR 1.45 [95% CI 1.15-1.84], p = 0.002) and a similar trend compared among AVC and nAVC (OR 1.25 [95% CI 0.98-1.60], p = 0.072), while mortality after distal pancreatectomy (DP) was not influenced by centre volume. CONCLUSIONS: Over the last two decades, centralisation of PS towards higher-volume centres was observed in Switzerland with a decrease of mortality after PD and low mortality after DP. Further centralisation is supported by most pancreatic surgeons. However, the ideal metric and outcome measures for the allocation of highly specialised medicine need further discussion to allow a fair and outcome-focused allocation.

Inequalities in access to minimally invasive general surgery: a comprehensive nationwide analysis across 20 years.

BACKGROUND: Minimally invasive surgery (MIS) has profoundly changed standards of care and lowered perioperative morbidity, but its temporal implementation and factors favoring MIS access remain elusive. We aimed to comprehensibly investigate MIS adoption across different surgical procedures over 20 years, identify predictors for MIS amenability and compare propensity score-matched outcomes among MIS and open surgery. METHODS: Nationwide retrospective analysis of all hospitalizations in Switzerland between 1998 and 2017. Appendectomies (n = 186,929), cholecystectomies (n = 57,788), oncological right (n = 9138) and left hemicolectomies (n = 21,580), rectal resections (n = 13,989) and gastrectomies for carcinoma (n = 6606) were included. Endpoints were assessment of temporal MIS implementation, identification of predictors for MIS access and comparison of propensity score-matched outcomes among MIS and open surgery. RESULTS: The rates of MIS increased for all procedures during the study period (p ≤ 0.001). While half of all appendectomies were performed laparoscopically by 2005, minimally invasive oncological colorectal resections reached 50% only by 2016. Multivariate analyses identified older age (p ≤ 0.02, except gastrectomy), higher comorbidities (p ≤ 0.001, except rectal resections), lack of private insurance (p ≤ 0.01) as well as rural residence (p ≤ 0.01) with impaired access to MIS. Rural residence correlated with low income regions (p ≤ 0.001), which themselves were associated with decreased MIS access. Geographical mapping confirmed strong disparities for rural and low-income areas in MIS access. Matched outcome analyses revealed benefits of MIS for length of stay, decreased surgical site infection rates for MIS appendectomies and cholecystectomies and higher mortality for open cholecystectomies. No consistent morbidity or mortality benefit for MIS compared to open colorectal resections was observed. CONCLUSION: Unequal access to MIS exists in disfavor of older and more comorbid patients and those lacking private insurance, living in rural areas, and having lower income. Efforts should be made to ensure equal MIS access regardless of socioeconomic or geographical factors.

Mutations of RAS/RAF Proto-oncogenes Impair Survival After Cytoreductive Surgery and HIPEC for Peritoneal Metastasis of Colorectal Origin.

BACKGROUND: Adequate selection of patients with peritoneal metastasis (PM) for cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) remains critical for successful long-term outcomes. Factors reflecting tumor biology are currently poorly represented in the selection process. The prognostic relevance of RAS/RAF mutations in patients with PM remains unclear. METHODS: Survival data of patients with colorectal PM operated in 6 European tertiary centers were retrospectively collected and predictive factors for survival identified by Cox regression analyses. A simple point-based risk score was developed to allow patient selection and outcome prediction. RESULTS: Data of 524 patients with a median age of 59 years and a median peritoneal cancer index of 7 (interquartile range: 3-12) were collected. A complete resection was possible in 505 patients; overall morbidity and 90-day mortality were 50.9% and 2.1%, respectively. PCI [hazard ratio (HR): 1.08], N1 stage (HR: 2.15), N2 stage (HR: 2.57), G3 stage (HR: 1.80) as well as KRAS (HR: 1.46) and BRAF (HR: 3.97) mutations were found to significantly impair survival after CRS/HIPEC on multivariate analyses. Mutations of RAS/RAF impaired survival independently of targeted treatment against EGFR. Consequently, a simple point-based risk score termed BIOSCOPE (BIOlogical Score of COlorectal PEritoneal metastasis) based on PCI, N-, G-, and RAS/RAF status was developed, which showed good discrimination [development area under the curve (AUC) = 0.72, validation AUC = 0.70], calibration (P = 0.401) and allowed categorization of patients into 4 groups with strongly divergent survival outcomes. CONCLUSION: RAS/RAF mutations impair survival after CRS/HIPEC. The novel BIOSCOPE score reflects tumor biology, adequately stratifies long-term outcomes, and improves patient assessment and selection.

Perfusion settings and additives in liver normothermic machine perfusion with red blood cells as oxygen carrier. A systematic review of human and porcine perfusion protocols.

Liver machine perfusion (MP) at normothermic temperature (NMP) is a promising way to preserve and evaluate extended criteria donor livers. Currently, no consensus exists in methodology and perfusion protocols. Here, the authors performed a systematic literature search to identify human and porcine studies reporting on liver NMP with red blood cells. A qualitative synthesis was performed concerning technical aspects of MP, fluid composition, gas supply, and liver positioning. Thirty-seven publications including 11 human and 26 porcine studies were considered for qualitative synthesis. Control mode, pressure, flow, perfusate additives, and targeted blood gas parameters varied across human as well as porcine studies. For future analyses, it is advisable to report flow adjusted to liver weight and exact pressure parameters including mean, systolic, and diastolic pressure. Parenteral nutrition and insulin addition was common. Parenteral nutrition included amino acids and/or glucose without lipids. Taurocholic acid derivatives were used as bile flow promoters. However, short-term human NMP without taurocholic acid derivatives seems to be possible. This finding is relevant due to the lack of clinical grade bile salts. Near physiological oxygen tension in the perfusate is doable by adjusting gas flows, while blood gas parameters regulation needs more detailed description.

Insurance status does not affect short-term outcomes after oncological colorectal surgery in Europe, but influences the use of minimally invasive techniques: a propensity score-matched analysis.

BACKGROUND AND PURPOSE: Controversy exists whether surgical treatment is influenced by insurance status. American studies suggest higher morbidity and decreased survival in uninsured patients with colorectal cancer (CRC). It remains elusive, however, whether these findings apply to European countries with mandatory, government-driven insurance systems. We aimed to analyze whether operative techniques, quality of surgery, and complication rates differ among patients covered by statutory (SI) versus private (PI) healthcare insurance. METHODS: Based on a prospective national surgical quality database, patients undergoing elective resection for CRC during 2007-2015 were identified. A propensity score match of eligible patients with SI and PI yielded 765 patients per group. RESULTS: Hierarchical status of the operating surgeon differed substantially (p = 0.001): junior surgeons operated on > 50% of patients with SI, whereas over 80% of patients with PI were operated by senior surgeons. Minimally invasive techniques were used more frequently in patients with PI (p = 0.001) and patients with SI undergoing colonic resection showed an increased conversion rate (OR 2.44). Median duration of surgery (p = 0.001) and blood loss (p = 0.002) were higher in patients with SI; however, length of hospital stay was equal. Neither the rate of positive resection margins nor the number of resected lymph nodes differed among groups. Complications and mortality occurred with similar frequencies for patients undergoing colon (p = 0.140) and rectal (p = 0.335) resection. CONCLUSION: The use of minimally invasive techniques was favored in patients with PI; however, the quality of oncological resection was not affected by insurance status and only minor differences in perioperative complications observed.

Major Postoperative Complications Are a Risk Factor for Impaired Survival after CRS/HIPEC.

BACKGROUND: Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is a combined treatment option for well-selected patients with peritoneal carcinomatosis (PC). The study aimed to identify factors influencing cancer-specific survival (CSS) and disease-free survival (DFS). METHODS: Data of 113 patients with colorectal or appendicular carcinomatosis from a single center operated between 2009 and 2014 were retrospectively collected and analyzed. Patients with high-grade tumors received standard perioperative chemotherapy, and patients with low-grade appendix tumors were directly operated. HIPEC was performed after radical CRS. RESULTS: Patients had carcinomatosis from appendix neoplasms in 63% (71/113), including low-grade and high-grade tumors, and colorectal cancer in 37% (42/113). Complete cytoreduction and HIPEC were possible in 67% of patients. Major morbidity occurred in 10.6% of patients, and mean follow-up was 28 months. For colorectal PC, median CSS and DFS were 40 and 12 months, respectively. Median DFS was 19 months for high-grade appendix tumors, while median CSS has not been reached. All patients with diffuse peritoneal adenomucinosis were still alive at time of analysis; rate of DFS was 96% for these patients after 3 years. Major postoperative complications (Clavien-Dindo IIIB or higher) and positive nodal state were associated with impaired CSS and DFS, while a peritoneal cancer index score of >10 was independently associated with impaired CSS. CONCLUSIONS: CRS/HIPEC offers a survival benefit in well-selected patients with PC. Major postoperative complications affect long-term oncologic outcome of these patients.

Detection rate of colorectal cancer by routine colonoscopy is comparable in patients aged 45-49 and 50-54 years.

OBJECTIVES: Colorectal carcinoma remains one of the most common malignancies worldwide. Colonoscopy screening is most effective for early detection and tumour prevention and is currently recommended in Europe for adults aged over 50 years. However, given that an increasing proportion of patients are diagnosed before the age of 50, we set out to determine the detection rate of colorectal carcinoma in patients younger than 50 years and to determine the best threshold for starting colonoscopy screening. METHODS: Single-centre, retrospective cohort study of all colonoscopies performed, regardless of indication, in our department at a tertiary Swiss university hospital in patients aged ≥18 and <60 years between 2016 and 2021. Colorectal cancer detection rate was calculated per 5-year age group and analysed separately by sex. RESULTS: The current analysis included 2846 colonoscopies performed for any indication. Colorectal carcinoma was found in 5/366 (1.4%) patients aged 45-49 years (3/210 or 1.4% of males and 2/156 or 1.3% of females) and in 9/819 (1.1%) patients aged 50-54 years (5/495 or 1.0% of males and 4/324 or 1.2% of females). Adenomas with high-grade dysplasia were found in 5/366 (1.4%) patients aged 45-49 years and in 11/819 (1.3%) aged 50-54 years; by sex, in 4/210 or 1.9% of males and 1/156 or 0.6% of females aged 45-49 years, and in 6/495 or 1.2% of males and 5/324 or 1.5% of females aged 50-54 years. Detection of adenoma with low-grade dysplasia increased from 14.6% (21/144) at age <30 years to 41% (150/366) at 45-49 years and 43.5% (356/819) at 50-54 years. A similar increasing trend was also seen if we analysed these groups by sex. CONCLUSIONS: The detection rate of colorectal carcinoma, but also adenomas, in our patients aged 45-49 years was similar to that in patients aged over 50, in both sexes. Thus our data are in line with the assumption that lowering the screening age to 45 years might be reasonable from a medical point of view for achieving a reduction in disease-specific mortality by improved screening strategies.

Quality of Life and Independent Factors Associated with Poor Digestive Function after Ivor Lewis Esophagectomy.

Transthoracic esophagectomy results in a radical change in foregut anatomy with multiple consequences for digestive physiology. The aim of this study was to identify factors associated with poor functional outcomes by assessing multiple dimensions of digestive performance and health-related quality of life (HRQL). Patients with cancer-free survival after Ivor Lewis esophagectomy were included. Four functional syndromes (dysphagia, gastroesophageal reflux disease (GERD), delayed gastric conduit emptying (DGCE), and dumping syndrome (DS)) and HRQL were assessed using specifically designed questionnaires. Patient outcomes were compared with healthy controls. Independent factors associated with poor digestive performance were identified through multivariable analysis. Sixty-five postoperative patients and 50 healthy volunteers participated in this study. Compared with controls, patients had worse outcomes for dysphagia, GERD, DS, and HRQL, but not for DGCE. A multivariate analysis showed a significant correlation of reduced digestive performance with ASA score, squamous cell carcinoma, open or hybrid surgical approach, and (neo)adjuvant therapy. In contrast, no individual patient factor was found to be associated with dumping syndrome. Digestive function and HRQL are substantially impaired after Ivor Lewis esophagectomy for cancer. Comorbid patients undergoing multimodal treatment and open access surgery for squamous cell carcinoma have the highest risk of poor functional outcome.

The Role of Pancreatic Stone Protein (PSP) as a Biomarker of Pregnancy-Related Diseases.

Background: Pancreatic stone protein (PSP) is a biochemical serum marker that contains levels that are elevated in various inflammatory and infectious diseases. The role of PSP in the diagnosis of these diseases seems to be more important compared to clinically established biochemical serum markers in discriminating the severity of the same diseases. Standard values for PSP in pregnant women in relation to gestational age have been reported recently. Additionally, increased PSP levels have been observed to be associated with renal dysfunction in pregnant women. The aim of this study is to evaluate the diagnostic role of PSP in pregnancy-related diseases, such as pre-eclampsia (PE), hemolysis-elevated liver enzymes, and low platelet (HELLP) syndrome. In addition, the study aims to assess its diagnostic role in inflammation-triggered diseases as preterm premature rupture of membranes (PPROM) or COVID-19-positive pregnant women. Materials and Methods: In this single-centred prospective study performed at a tertiary university hospital between 2013 and 2021, we included 152 pregnant women who were diagnosed with either PE, HELLP syndrome, or PPROM. In December 2020, in the context of the COVID-19 pandemic, the Independent Ethics Committee (IEC) approved an amendment to the study protocol. Depending on the underlying disease, single or serial-serum PSP measurements were assessed. These PSP values were compared to PSP levels of women with normal pregnancies. Results: Pregnant women diagnosed with pre-eclampsia or HELLP syndrome had significantly increased PSP values (mean 9.8 ng/mL, SD 2.6) compared to healthy singleton pregnant women (mean 7.9 ng/mL, SD 2.6, p ≤ 0.001). There was no difference in serum PSP in pregnant women with PPROM compared to women with uncomplicated singleton pregnancies (mean in PPROM: 7.9 ng/mL; SD 2.9 versus mean in healthy pregnancies: 7.9 ng/mL; SD 2.6, p = 0.98). Furthermore, no difference in the PSP values in women with or without intra-amniotic infection was observed (infection: mean 7.9 ng/mL; SD 2.8 versus no infection: mean 7.8 ng/mL; SD 3, p = 0.85). The mean value of PSP in COVID-19-infected women during pregnancy (8.5 ng/mL, SD 2.3) was comparable to healthy singleton pregnancies (mean 7.9 ng/mL, SD 2.6), p = 0.24. Conclusions: The novel serum biomarker PSP is significantly upregulated in pregnant women with pre-eclampsia and HELLP syndrome. Our observations call for the further evaluation of PSP in randomized controlled clinical trials to demonstrate the actual role of PSP in pregnancy-related diseases and whether it may provide new approaches for the management and discrimination of the severity of these gestational conditions.

Serum Pancreatic Stone Protein Reference Values in Healthy Pregnant Women: A Prospective Cohort Study.

BACKGROUND: In non-pregnant populations, pancreatic stone protein (PSP) has been reported to have a higher diagnostic performance for identifying severe inflammatory and infectious disease than other established biomarkers. OBJECTIVE: To generate reference values for serum PSP in pregnancy and compare them to the values of the general healthy population. DESIGN: A prospective cohort study. SETTING: A single center. POPULATION: Healthy women with singleton and multiple pregnancies. METHODS: This is a prospective single-center cohort study. Between 2013 and 2021, samples of 5 mL peripheral blood were drawn from 440 healthy pregnant women. Therein, 393 cases were singletons and 47 were multiple pregnancies. Serum PSP levels were measured by specific enzyme-linked immunosorbent assay. The main outcome measures were serum PSP level (ng/mL) reference values in healthy pregnant women. RESULTS: The mean PSP reference values in women with singleton pregnancies were 7.9 ± 2.6 ng/mL (95% CI; 2.69-13.03 ng/mL). The PSP values in women with multiple pregnancies (9.17 ± 3.06 ng/mL (95% CI; 3.05-15.28 ng/mL)) were significantly higher (p = 0.001). The PSP values in the first trimester (6.94 ± 2.53 ng/mL) were lower compared to the second (7.42 ± 2.21 ng/mL) and third trimesters (8.33 ± 2.68 ng/mL, p = 0.0001). Subgroup analyses in singletons revealed no correlations between PSP values, maternal characteristics, and pre-existing medical conditions. CONCLUSION: The PSP values in healthy pregnant women (4-12 ng/mL) were in the range of the reference values of the general healthy population (8-16 ng/mL). This insight blazes a trail for further clinical studies on the use of PSP as a potential novel biomarker for the early detection of pregnancy-related diseases such as chorioamnionitis.

First-in-human Use of a Microsurgical Robotic System for Central Lymphatic Reconstruction.

Advances in the development of robotic systems have recently enabled the use of robotic technology in reconstructive lymphatic surgery. Although the advantages of microsurgical robots must be weighed carefully against the costs, their use may allow for smaller surgical approaches and easier access to anatomically deeper structures or even smaller vessels. We report on a case of a patient with central lymphatic dilation causing abdominal pain and severely reduced physical capacity. Sonography-assisted intranodal injection of indocyanine green allowed for localization of the lymphatic cyst and anastomosis with the left ovarian vein, applying robotic-assisted microsurgery for the first time on the central lymphatic system. Following the successful reconstruction of lymphatic drainage and decompression of the cyst, the patient reported a complete regression of her preoperative symptoms. From a surgical point of view, the Symani Surgical System improved precision and allowed significantly smaller surgical access. Considering the high morbidity and rarity of pathologies of the central lymphatic system, central lymphatic surgery is to date rarely performed. With improved precision and significantly smaller surgical access, robotic-assisted microsurgery has great potential to expand the treatment options for central lymphatic lesions.

Colorectal cancer of the young displays distinct features of aggressive tumor biology: A single-center cohort study.

BACKGROUND: In recent years, a decrease in incidence and mortality of colorectal cancer (CRC) has been observed in developed nations, presumably through public disease awareness and increased screening efforts. However, a rising incidence of CRC in young patients below the age of 50 years has been reported in several studies. AIM: To study tumor biology in CRC patients below 50 years of age. METHODS: All patients with CRC were prospectively enrolled in our single-center oncologic database from January 2013 to December 2018 and were grouped and analyzed according to age (≥ 50 and < 50 years). Clinical as well as histopathological features were analyzed and compared. The study was approved by the local Ethics Committee. Fisher's exact test or t-test was used to test for differences between the groups, as appropriate. All statistical analysis was performed with IBM SPSS software Version 25 (SPSS Inc, Armonk, NY, United States) and with R-Studio using R Version 3.4.1 (RStudio, Boston, MA, United States). RESULTS: Seventeen percent of the 411 patients were younger than 50 years. Young patients were more often diagnosed with locally advanced T4-tumors and lymph node metastases (36.6% and 62% vs 17.7% and 42%; P < 0.01). In addition, a higher frequency of poorly differentiated (G3) tumors (40% vs 22.4% P < 0.05) was observed. More than every second patient below 40 years of age (51.8%) had distant metastases at diagnosis with a significant higher rate ring of signet cell differentiation compared to patients ≥ 50 years (14.8%, P < 0.05). Mutational status (KRAS, NRAS, BRAF, MSI) as well as selected behavioral risk factors showed no significant differences. CONCLUSION: Distinct histopathologic features of increased biologic aggressiveness are found in patients with CRC of young-onset. Those patients present more frequently with more advanced tumor stages compared to older patients. Features of aggressive tumor biology underscore the need for earlier uptake of routine screening measures.

Attenuation of peripheral serotonin inhibits tumor growth and enhances immune checkpoint blockade therapy in murine tumor models.

Platelet-derived peripheral serotonin has pleiotropic effects on coagulation, metabolism, tissue regeneration, and cancer growth; however, the effect of serotonin on the tumor microenvironment remains understudied. Peripheral serotonin­deficient (Tph1−/−) mice displayed reduced growth of subcutaneous and orthotopically injected syngeneic murine pancreatic and colorectal cancers with enhanced accumulation of functional CD8+ T cells compared to control C57BL/6 mice, resulting in extended overall survival. Subcutaneous and orthotopic syngeneic tumors from Tph1−/− mice expressed less programmed cell death 1 ligand 1 (PD-L1), suggesting serotonin-mediated regulation. Serotonin enhanced expression of PD-L1 on mouse and human cancer cells in vitro via serotonylation, which is the formation of covalent bonds between glutamine residues and serotonin, resulting in activation of small G proteins. Serotonin concentrations in metastases of patients with abdominal tumors negatively correlated to the number of CD8+ tumor-infiltrating T cells. Depletion of serotonin cargo or inhibition of serotonin release from thrombocytes decreased growth of syngeneic pancreatic and colorectal tumors in wild-type mice, increased CD8+ T cell influx, and decreased PD-L1 expression. Pharmacological serotonin depletion with oral fluoxetine or intraperitoneal injection of the TPH1 inhibitor telotristat augmented the effects of programmed cell death protein 1 (PD-1) checkpoint blockade and triggered long-term tumor control in mice subcutaneously inoculated with syngeneic colorectal and pancreatic tumors. Overall, peripheral serotonin weakens effector functions of CD8+ T cells within tumors. Clinically approved serotonin targeting agents alone or in combination with PD-1 blockade provided long-term control of established tumors in murine models, warranting further investigation of the clinical translatability of these findings.