Intraperitoneal administration of carcinoembryonic antigen-directed chimeric antigen receptor T cells is a robust delivery route for effective treatment of peritoneal carcinomatosis from colorectal cancer in pre-clinical study.

BACKGROUND AIMS: Peritoneal carcinomatosis (PC) from colorectal cancer (CRC) is a highly challenging disease to treat. Systemic chimeric antigen receptor (CAR) T cells have shown impressive efficacy in hematologic malignancies but have been less effective in solid tumors. We explored whether intraperitoneal (i.p.) administration of CAR T cells could provide an effective and robust route of treatment for PC from CRC. METHODS: We generated second-generation carcinoembryonic antigen (CEA)-specific CAR T cells. Various animal models of PC with i.p. and extraperitoneal metastasis were treated by i.p. or intravenous (i.v.) administration of CEA CAR T cells. RESULTS: Intraperitoneally administered CAR T cells exhibited superior anti-tumor activity compared with systemic i.v. cell infusion in an animal model of PC. In addition, i.p. administration conferred a durable effect and protection against tumor recurrence and exerted strong anti-tumor activity in an animal model of PC with metastasis in i.p. or extraperitoneal organs. Moreover, compared with systemic delivery, i.p. transfer of CAR T cells provided increased anti-tumor activity in extraperitoneal tumors without PC. This phenomenon was further confirmed in an animal model of pancreatic carcinoma after i.p. administration of our newly constructed prostate stem cell antigen-directed CAR T cells. CONCLUSIONS: Taken together, our data suggest that i.p. administration of CAR T cells may be a robust delivery route for effective treatment of cancer.

Understanding CAR T cell therapy and its role in ovarian cancer and peritoneal carcinomatosis from ovarian cancer.

Ovarian cancer is the seventh most common cancer worldwide in women and the most lethal gynecologic malignancy due to the lack of accurate screening tools for early detection and late symptom onset. The absence of early-onset symptoms often delays diagnosis until the disease has progressed to advanced stages, frequently when there is peritoneal involvement. Although ovarian cancer is a heterogeneous malignancy with different histopathologic types, treatment for advanced tumors is usually based on chemotherapy and cytoreduction surgery. CAR T cells have shown promise for the treatment of hematological malignancies, though their role in treating solid tumors remains unclear. Outcomes are less favorable owing to the low capacity of CAR T cells to migrate to the tumor site, the influence of the protective tumor microenvironment, and the heterogeneity of surface antigens on tumor cells. Despite these results, CAR T cells have been proposed as a treatment approach for peritoneal carcinomatosis from colorectal and gastric origin. Local intraperitoneal administration of CAR T cells has been found to be superior to systemic administration, as this route is associated with increased tumor reduction, a more durable effect, protection against local relapse and distant metastases, and fewer systemic adverse effects. In this article we review the application of CAR T cells for the treatment of ovarian cancer and peritoneal carcinomatosis from ovarian cancer.

Under the Hood: Understanding the Features of Mucin in Pseudomyxoma Peritonei.

Pseudomyxoma peritonei (PMP) is a rare malignant growth characterized by the production of mucin and the potential for peritoneal relapse. This study aimed to investigate the immunohistochemical and biological characteristics of mucin in patients with cellular and acellular PMP. We prospectively analyzed mucin specimens obtained from our patient cohort and described the composition and type of mucin present in each sample. A metagenomic analysis of the samples was performed to investigate the bacterial composition of the PMP microbiome. Secreted mucins 2 and 5AC and membrane-associated mucin-1 were the primary components of mucin in both cellular and acellular tumor specimens. The metagenomic study revealed a predominance of the phylum Proteobacteria and the genus Pseudomonas. Notably, Pseudomonas plecoglossicida, a species not previously reported in the human microbiome, was found to be the most abundant organism in the mucin of pseudomyxoma peritonei. Our findings suggest that the presence of MUC-2 and mucin colonization by Pseudomonas are characteristic features of both cellular and acellular disease. These results may have significant implications for the diagnosis and treatment of this rare entity.

Study of the Effect of Wild-Type and Transiently Expressing CXCR4 and IL-10 Mesenchymal Stromal Cells in a Mouse Model of Peritonitis.

Sepsis due to peritonitis is a process associated with an inflammatory state. Mesenchymal stromal cells (MSCs) modulate the immune system due to the paracrine factors released and may be a therapeutic alternative. Three treatment groups were developed in a murine model of peritonitis to verify the effect of human adipose mesenchymal stem cell (hASCs). Additionally, a temporary modification was carried out on them to improve their arrival in inflamed tissues (CXCR4), as well as their anti-inflammatory activity (IL-10). The capacity to reduce systemic inflammation was studied using a local application (peritoneal injection) as a treatment route. Comparisons involving the therapeutic effect of wild-type ASCs and ASCs transiently expressing CXCR4 and IL-10 were carried out with the aim of generating an improved anti-inflammatory response for sepsis in addition to standard antibiotic treatment. However, under the experimental conditions used in these studies, no differences were found between both groups with ASCs. The peritoneal administration of hASCs or genetically modified hASCs constitutes an efficient and safe therapy in our model of mouse peritonitis.

An international consensus for mitigation of the detrimental effects of the COVID-19 pandemic on laparoscopic training.

AIM: Achieve an international consensus on how to recover lost training opportunities. The results of this study will help inform future EAES guidelines about the recovery of surgical training before and after the pandemic. BACKGROUND: A global survey conducted by our team demonstrated significant disruption in surgical training during the COVID-19 pandemic. This was wide-spread and affected all healthcare systems (whether insurance based or funded by public funds) in all participating countries. Thematic analysis revealed the factors perceived by trainees as barriers to training and gave birth to four-point framework of recovery. These are recommendations that can be easily achieved in any country, with minimal resources. Their implementation, however, relies heavily on the active participation and leadership by trainers. Based on the results of the global trainee survey, the authors would like to conduct a Delphi-style survey, addressed to trainers on this occasion, to establish a pragmatic step-by-step approach to improve training during and after the pandemic. METHODS: This will be a mixed qualitative and quantitative study. Semi-structured interviews will be performed with laparoscopic trainers. These will be transcribed and thematic analysis will be applied. A questionnaire will then be proposed; this will be based on both the results of the semi structured interviews and of the global trainee survey. The questionnaire will then be validated by the steering committee of this group (achieve consensus of >80%). After validation, the questionnaire will be disseminated to trainers across the globe. Participants will be asked to consent to participate in further cycles of the Delphi process until more than 80% agreement is achieved. RESULTS: This study will result in a pragmatic framework for continuation of surgical training during and after the pandemic (with special focus on minimally invasive surgery training).

Chemical Scalpel: An Experimental Collagenase-Based Treatment for Peritoneal Adhesions.

(1) Background: Abdominal adhesions are a common disease appearing after any type of abdominal surgery and may prolong surgical time and cause intestinal obstruction, infertility, or chronic pain. We propose the use of intraperitoneal collagenase to perform chemical adhesiolysis based on the pathophysiology and histology of adhesions. (2) Methods: We generated an adhesion model with intraperitoneal polypropylene meshes. Four months later, we evaluated the efficacy of the treatment in blinded form, i.e., 0.05% collagenase vs. placebo at 37 °C for 20 min. Protocol 1: Ten rats with ten mesh fragments, in which an attempt was made to remove the maximum number of meshes in a 5-min period. Protocol 2: Six rats with four mesh fragments in the sides of the abdominal cavity in which adhesiolysis was performed using a device that measures burst pressure. (3) Results: Protocol 1: 42% efficacy in the collagenase group versus 8% in the control group (p < 0.013). Protocol 2: 188.25 mmHg (SD 69.65) in the collagenase group vs. 325.76 mmHg (SD 50.25) in the control group (p < 0.001). (4) Conclusions: Collagenase allows for the safe and effective chemical adhesiolysis in this experimental model of adhesions.

Update for Advance CAR-T Therapy in Solid Tumors, Clinical Application in Peritoneal Carcinomatosis From Colorectal Cancer and Future Prospects.

Latest advances in the field of cancer immunotherapy have developed the (Chimeric Antigen Receptor) CAR-T cell therapy. This therapy was first used in hematological malignancies which obtained promising results; therefore, the use of CAR-T cells has become a popular approach for treating non-solid tumors. CAR-T cells consist of T-lymphocytes that are engineered to express an artificial receptor against any surface antigen of our choice giving us the capacity of offering precise and personalized treatment. This leaded to the development of CAR-T cells for treating solid tumors with the hope of obtaining the same result; however, their use in solid tumor and their efficacy have not achieved the expected results. The reason of these results is because solid tumors have some peculiarities that are not present in hematological malignancies. In this review we explain how CAR-T cells are made, their mechanism of action, adverse effect and how solid tumors can evade their action, and also we summarize their use in colorectal cancer and peritoneal carcinomatosis.

Analysis of Septin 9 Gene Hypermethylation as Follow-Up Biomarker of Colorectal Cancer Patients after Curative Surgery.

BACKGROUND: The Septin 9 test analyzes the methylation status of the SEPT9 gene, which appears to be hypermethylated in patients with colorectal cancer (CRC). This has been validated as a colorectal cancer screening test. Due to the high sensitivity and specificity found, the justification was to use it as a biomarker tool for monitoring minimal residual disease after radical surgery and recurrence. METHODS: A prospective study was carried out at the Fundación Jiménez Díaz University Hospital extracting peripheral blood from 28 patients and 4 healthy donors. Free circulating DNA was obtained and subsequently a PCR reaction to quantify the number of methylated genes. Samples were obtained preoperatively and postoperatively at five to seven days, one and three months after surgery. RESULTS: A total of 32 preoperative samples were analyzed. The sensitivity of the test to detect CRC was 55.6% and specificity was 100%. There were 22 postsurgical samples obtained at 5-7 days after surgery, the sensitivity to detect tumor recurrences was 100% and specificity was 75%. There were 21 samples analyzed 1 month after surgery exhibiting a sensitivity and specificity of 100% and 94.7%, respectively. At 3 months, 31 postsurgical samples were analyzed and the sensitivity and specificity were 66.7% and 80%. CONCLUSIONS: Detection of methylation of Septin 9 gene in circulating plasma DNA, obtained from a peripheral blood sample, may be a useful, non-invasive and effective method for detecting minimal residual disease and could therefore predict CRC tumor recurrences. The optimal time in our series to obtain the best prediction results based on Septin 9 methylation levels was one month after surgery. Despite these considerable findings, a study with more patients is necessary to obtain more robust conclusions.

Stem cell therapy applied for digestive anastomosis: Current state and future perspectives.

BACKGROUND: Digestive tract resections are usually followed by an anastomosis. Anastomotic leakage, normally due to failed healing, is the most feared complication in digestive surgery because it is associated with high morbidity and mortality. Despite technical and technological advances and focused research, its rates have remained almost unchanged the last decades. In the last two decades, stem cells (SCs) have been shown to enhance healing in animal and human studies; hence, SCs have emerged since 2008 as an alternative to improve anastomoses outcomes. AIM: To summarise the published knowledge of SC utilisation as a preventative tool for hollow digestive viscera anastomotic or suture leaks. METHODS: PubMed, Science Direct, Scopus and Cochrane searches were performed using the key words "anastomosis", "colorectal/colonic anastomoses", "anastomotic leak", "stem cells", "progenitor cells", "cellular therapy" and "cell therapy" in order to identify relevant articles published in English and Spanish during the years of 2000 to 2021. Studies employing SCs, performing digestive anastomoses in hollow viscera or digestive perforation sutures and monitoring healing were finally included. Reference lists from the selected articles were reviewed to identify additional pertinent articles.Given the great variability in the study designs, anastomotic models, interventions (SCs, doses and vehicles) and outcome measures, performing a reliable meta-analysis was considered impossible, so we present the studies, their results and limitations. RESULTS: Eighteen preclinical studies and three review papers were identified; no clinical studies have been published and there are no registered clinical trials. Experimental studies, mainly in rat and porcine models and occasionally in very adverse conditions such as ischaemia or colitis, have been demonstrated SCs as safe and have shown some encouraging morphological, functional and even clinical results. Mesenchymal SCs are mostly employed, and delivery routes are mainly local injections and cell sheets followed by biosutures (sutures coated by SCs) or purely topical. As potential weaknesses, animal models need to be improved to make them more comparable and equivalent to clinical practice, and the SC isolation processes need to be standardised. There is notable heterogeneity in the studies, making them difficult to compare. Further investigations are needed to establish the indications, the administration system, potential adjuvants, the final efficacy and to confirm safety and exclude definitively oncological concerns. CONCLUSION: The future role of SC therapy to induce healing processes in digestive anastomoses/sutures still needs to be determined and seems to be currently far from clinical use.

Upfront surgery versus self-expanding metallic stent as bridge to surgery in left-sided colonic cancer obstruction: A multicenter observational study.

BACKGROUND: Oncological outcomes of self-expanding metallic stent used as a bridge to surgery in potential curative patients with left-sided colonic cancer obstruction remain unclear. The aim of this study was to investigate perioperative and mid-term oncological outcomes of 2 of the currently most commonly performed treatments in left-sided colonic cancer obstruction. METHODS: This is a retrospective multicenter study including patients with left-sided colonic cancer obstruction treated with curative intent between 2013 and 2017. The presence of metastasis at diagnosis was an exclusion criterion. The primary outcome was to evaluate the noninferiority, in terms of overall survival, of bridge to surgery strategy compared with emergency colonic resection. The secondary outcomes were perioperative morbimortality, disease free survival, local recurrence, and distant recurrence. RESULTS: A total of 564 patients were included, 320 in the emergency colonic resection group and 244 in the bridge to surgery group. Twenty-seven patients of the bridge-to-surgery group needed urgent operation. Postoperative morbidity rates were statistically higher in the emergency colonic resection group (odds ratio [95% confidence interval] 0.37 [0.24-0.55], P < .001). There was no difference in 90-day mortality between groups (odds ratio [95% confidence interval] 0.85 [0.36-1.99], P = .702). The median follow-up was 3.80 years (2.29-4.92). The results show the noninferiority of bridge to surgery versus emergency colonic resection in terms of overall survival (hazard ratio [95% confidence interval) 0.78 [0.56-1.07], P = .127). There were no differences in disease free survival, distant recurrence, and local recurrence rates between bridge to surgery and emergency colonic resection groups. CONCLUSION: Self-expanding metallic stent as bridge to surgery might not lead to a negative impact on the long-term prognosis of the tumor compared with emergency colonic resection in expert hands and selected patients.

The Role of Shared Decision-Making in Personalised Medicine: Opening the Debate.

Surgeons and cancer patients are starting to open the debate on how personalised medicine could use shared decision-making (SDM) to balance the personal and clinical components and thus improve the quality and value of care. Personalised precision medicine (PPM) has traditionally focused on the use of genomic information when prescribing treatments, which are usually pharmaceutical. However, the knowledge base is considerably scarcer in terms of how clinicians can individualise the information they provide patients about the consequences of different treatments, and in doing so involve them in the decision-making process. To achieve this, the ethical implications of SDM must be addressed from both sides. This paper explores the medical characteristics, the SDM implications in severe and fragile patients, potential risks, and observed benefits within this healthcare approach through four clinical cases. Findings shed light on current needs for clinician and patient training and tools related to SDM in PPM, and also remarks on the way in which this shift in healthcare settings is taking place to include the human component together with the biological and technological advances when designing care processes in colorectal cancer.

Towards an Open Medical School without Checkerboards during the COVID-19 Pandemic: How to Flexibly Self-Manage General Surgery Practices in Hospitals?

BACKGROUND: Can we create a technological solution to flexibly self-manage undergraduate General Surgery practices within hospitals? Before the pandemic, the management of clerkships was starting to depend less on checkerboards. This study aims to explore undergraduates' perceptions of doing rotations in teaching hospitals using different teaching styles and elicit their views regarding the options of managing practices to design a mobile app that substitutes for checkerboards. METHODS: In this sequential exploratory mixed methods study, 38 semi-structured interviews at a teaching hospital were conducted. The data was used to survey 124 students doing their rotations in four teaching hospitals during the first wave of COVID-19. RESULTS: 21 themes highlighted concerns related to the practices, the teacher involvement in the students' education, and the students' adaptation to clinical culture. The students reported positive perceptions concerning self-managing and organizing practices via a mobile application. However, problems emerged regarding transparency, the lack of feedback, and the need for new tools. Regarding the teaching styles, the facilitator and personal models were perceived as optimal, but the personal style had no effect on using or not using a tool. CONCLUSIONS: A mobile-learning application designed like an educational opportunities' manager tool can probably promote self-directed learning, flexible teaching, and bidirectional assessments. However, teachers who employ a personal teaching style may not need either checkerboards or a tool. This solution supports teaching at hospitals in pandemic times without checkerboards.

Implementation barriers for Enhanced Recovery After Surgery (ERAS) in rectal cancer surgery: a comparative analysis of compliance with colon cancer surgeries.

We aim to analyze differences in compliance between colon and rectal cancer surgeries under Enhanced Recovery After Surgery (ERAS) for colorectal procedures, and to detect implementation barriers for rectal cancer surgeries. Patients who underwent elective rectal cancer surgeries under ERAS were case-matched based on gender, age, and P-POSSUM with an equal number of patients who underwent colonic surgeries. Achievements of ≥ 70% of ERAS items were considered an acceptable level of compliance. A multivariate analysis was carried out to identify independent risk factors for lower compliance. A total of 434 patients were included over a 5-year period. After matching, there were 111 patients in each group. Overall compliance was significantly lower in the rectal surgery group (73% vs 82%, p = 0.001). A good compliance rate differed from 55% in rectal vs 77.5% in colonic procedures (p = 0.000). We identified three independent risk factors for lower compliance rates: open surgical approach, the use of epidural catheter, and the presence of postoperative ileus. Our data showed that rectal cancer surgeries are more exigent to success on ERAS interventions when compared to colonic resections. There is a need to introduce specific modifications on the protocols for colorectal surgeries when applied to these particular procedures.