Gastrointestinal Sites Research Articles

Physical pressure resistance of gastrointestinal anastomotic site via plate of polyglycolic acid promoting fibrosis

Anastomotic-leakage incidence has been reported to be reduced on using polyglycolic acid (PGA) sheets as reinforcing materials; however, there is insufficient evidence regarding the reinforcement mechanism. Therefore, we investigated effects of PGA sheets on gastrointestinal anastomoses in rats. In the first approach, five rats underwent laparotomy; the PGA sheet was pasted onto the normal cecal wall. After five days, the cecum was removed and histologically evaluated. In the second approach, ten rats were randomly divided into two groups of five animals each. The rats underwent laparotomy; the cecal wall was sutured after a full-thickness incision. In the PGA group, a PGA sheet was used to cover the suture area. After 5 days, the cecum was removed, and the physical pressure resistance was evaluated. We confirmed the growth of a fibrous capsule measuring 855 (648–1048) µm outside the cecal serosa in the first approach. The median pressure resistance in the second approach was 57.0 (45.0–90.0) and 90.0 (82.5–94.5) mmHg in Control and PGA groups, respectively. The pressure resistance was significantly higher in the PGA group (p = 0.046). In summary, the PGA sheet may form a barrier of fibrosis on the intestinal wall and provide reinforcement to prevent anastomotic leakage.

Histology-Proven Gastrointestinal Metastasis from Nongastrointestinal Malignancies: Experience of This Rare Occurrence in a Single Center

Introduction Lymph nodes, lung, liver, bone, and brain are the commonest metastatic sites for malignancies arising in various body sites. Gastrointestinal (GI) tract is a very uncommon metastatic site and the present study describes the single-center experience of GI metastases from non-GI malignancies. Aims and Objectives To study the spectrum of metastatic tumors to GI tract and elucidate their clinicopathological characteristics. Materials and Methods This was a retrospective study done on cases diagnosed from 2015 to 2023 at our institute. All cases of non-GI malignancies metastatic to hollow GI tract were included. Cases with GI primary, hematological malignancies, cases with exclusive serosal deposits, and direct invasion of a GI organ from an adjacent primary tumor were excluded. Apart from hematoxylin & eosin (H&E)-stained slides, immunohistochemistry findings of these were reviewed. Results Thirty-six patients were histologically proven GI metastases from non-GI malignancies diagnosed during the study period. Most cases were seen in 5th to 7th decade with a significant female preponderance (M:F of 1:8). The commonest metastatic GI sites were small bowel (n = 11), sigmoid colon (n = 9), and rectum (n = 7), followed by stomach (n = 3), appendix (n = 3), gall bladder (n = 2), and ampulla (n = 1). Stricture, perforation, and nodular mucosa were the most common endoscopic findings. The most common primary malignancies in females were ovarian serous carcinoma (n =21) followed by squamous cell carcinoma (SCC) of cervix (n = 8). In males, there was no site preference, and the primary sites included prostate, lung, kidney, and oral mucosa. Conclusion The study highlights the rare occurrence of GI metastases from non-GI malignancies. Females are at greater risk of such metastases primarily from ovarian serous carcinoma and cervical SCCs.

Association between prophylactic closure of mucosal defect and delayed adverse events after endoscopic resection: a systematic review and meta-analysis

ObjectiveTo investigate the potential of prophylactic closure of mucosal defects to prevent adverse events following endoscopic resection of superficial layers of the gastrointestinal (GI) wall.DesignSystematic review and meta-analysis.Data sourcesWe searched...

Perspective: on the future of fecal microbiota transplantation.

Fecal Microbiota Transplantation (FMT) has shown to possess impressive potential benefit for a wide range of clinical indications. Due to its inherent safety issues and efficacy constraints, the use of personalized FMT analogs could be a promising avenue. The development of such analogs will require a detailed understanding of their functionality, encompassing not only microbe-host interactions of the microbial taxa that are involved, but also of the ecological dimensions of the analogs and an overview of the gastrointestinal sites where these relevant microbial interactions take place. Moreover, characterization of taxa that have been lost due to diminished exposure to beneficial microbes, as a consequence of Western lifestyle, may lead to creation of future FMT analogs with the capacity to restore functionalities that we have lost.

ERAS and Gastrointestinal Site Infections: Insights from a Comprehensive Systematic Review and Meta-Analysis.

Background: Enhanced recovery after surgery (ERAS) protocols are proposed to enhance perioperative care, but their impact on various surgical outcomes requires further insight. Objective: This extensive meta-analysis aimed to systematically estimate the effectiveness of ERAS in reducing postoperative complications and improving recovery metrics. Materials and Methods: We meticulously searched multiple databases and rigorously screened studies, ultimately including 16 high-quality research articles in our meta-analysis. We carefully assessed heterogeneity using the Cochran Q test and I2 index. Results were visualized using forest plots, displaying effect sizes and 95% confidence intervals (CIs). Results: The current meta-analysis reveals compelling evidence of ERAS protocols' impact on postoperative effects. Lung infection rates were significantly reduced, with an odds ratio (OR) of 0.4393 (95% CI: 0.2674; 0.7216, p = 0.0012), highlighting the protocols' effectiveness. Although the reduction in surgical site infections (SSIs) was not significant, with an OR of 0.8003 (95% CI: 0.3908; 1.6389, p = 0.5425), the data suggests a trend toward benefit. Urinary tract infections (UTI) also showed a promising decrease, with an OR of 0.4754 (95% CI: 0.2028; 1.1143, p = 0.0871), revealing ERAS protocols may mitigate UTI risks. No significant effects were observed on postoperative anastomotic leakage or ileus, with ORs indicating neutrality. The incidence of readmission was similarly unaffected, with an OR of 1.4018 (95% CI: 0.6860; 2.8647, p = 0.3543). These outcomes underscore the selective efficacy of ERAS protocols, advocating for their strategic implementation to optimize surgical recovery. Conclusions: This meta-analysis offers compelling evidence supporting the implementation of ERAS in mitigating specific post-surgical conditions. It underscores the potential of ERAS to enhance recovery experiences and improve healthcare efficiency. Further targeted research is warranted to fully understand the impact of ERAS on SSI, anastomotic leakage, ileus, and readmissions and to optimize its benefits across diverse surgical populations.

Modulations in gastrointestinal microbiota during postpartum period fulfill energy requirements and maintain health of lactating Tibetan cattle.

Postpartum period of dairy cattle is an important phase of their life mainly associated with the changes in physiology, rumen function, and energy metabolism. Studies have shown that gut microbial composition undergoes drastic changes during the postpartum period. However, little is known about the temporal variations in digestive tract microbiota in postpartum Tibetan cattle. The aim of this study was to investigate the temporal variations in blood metabolites, ruminal fermentation, and microbial community of oral, rumen, and gut in lactating Tibetan cattle during postpartum. We collected blood, saliva, rumen fluid, and fecal samples from lactating Tibetan cattle during 1st week (1 W), the 2nd week (2 W), the 1st month (1 M), and the 2nd month (2 M) of the postpartum period. The microbiota of saliva, rumen fluid, and fecal samples were assessed using 16S rRNA sequencing. The rumen volatile fatty acid and blood parameters were also quantified. The content of volatile fatty acids (VFAs) and blood parameters showed opposite tendency to each other and reached to stability at 2 M. Rumen microbiota showed the highest alpha diversity compared to other two sites. At phylum level, the oral cavity was dominated by Proteobacteria, while most dominant phylum in rumen and feces were Firmicutes and Bacteroidetes, respectively. The dominant genera in oral cavity were Moraxella and Bibersteinia, while genera Prevotella 1 and Ruminococcaceae UCG-005 were dominant in rumen and fecal samples, respectively. Microbial network analysis revealed that most of the active genera in all networks belonged to phylum Firmicutes, indicating the importance of this phyla during postpartum period of lactating cattle. The functional analysis revealed distinct division of labor among three gastrointestinal sites associated with defense, fatty acid synthesis, and maintaining health of host. All in all, our findings provide insights into the metabolic and microbial changes of lactating Tibetan cattle and help to the improvement of the management strategies.

PCSK2 can be Useful in a Panel Approach to Distinguish Foregut and Midgut Neuroendocrine Tumors.

A number of immunohistochemical stains have been examined for utility in establishing the site of origin for metastatic well-differentiated neuroendocrine tumors (NETs). In the gastrointestinal (GI) tract, distinguishing metastatic duodenal NETs from jejunoileal and other GI NETs is important for clinical work-up, prognosis, and therapy. A recent study indicated that prohormone convertase 2 (PCSK2 or PC2) had broad expression in small intestine and appendiceal NETs. Because the study did not include duodenal NETs, we examined PCSK2 expression in duodenal and other GI NETs. GI NETs (n = 69) and 13 corresponding lymph node metastases from stomach, duodenum, pancreas, ileum, appendix, and rectum were evaluated for the expression of PCSK2, along with ISL1, NKX2.2, CDX2, SATB2, and PAX8. Expression of each stain was evaluated using the H-score system, and differences in expression by site were evaluated by the chi square test. PCSK2 was expressed at similar frequency in duodenal (50%), pancreatic (59%), and ileal NETs (40%). PCSK2 was infrequently expressed in stomach (0%), appendiceal (8%), and rectal (25%) NETs. However, incorporating PCSK2 into a panel including ISL1, NKX2.2, CDX2, and SATB2 allowed development of an algorithm which had 87% sensitivity and 93% specificity for classification of ileal NETs; and 68% sensitivity and 98% specificity for pancreaticoduodenal NETs. In contrast to previous findings, PCSK2 does not show specificity for any particular GI site. An algorithmic approach incorporating the expression of PCSK2 with that of ISL1, NKX2.2, CDX2, and SATB2 is useful in discriminating pancreatic, duodenal, ileal, appendiceal, and rectal NETs.

A review of Radiological Imaging Features to ameliorate radiologists’ knowledge of Krukenberg Tumor (KT)

Object: Aim is to delineate the major radiological findings with US, CT and MR of the Krukenberg tumor. Method: Revision of the literature. Introduction: A Krukenberg tumor refers tipically to a gastrointestinal cancer that metastasizes to the ovaries; this tumor was named after Krukenberg, who originally described this pathologic condition of the ovaries in 1896. The prognosis of this tumor is uniformly poor.[1] Discussion: Krukenburg tumor (KT)is a metastatic malignancy of the ovary characterized by mucin-rich signet-ring adenocarcinoma that primarily arises from a gastrointestinal site in most cases and less commonly from other sites. Often these tumors are bilateral (over 80%), given their metastatic nature. The images of a Krukenberg tumor highlight that the masses are mostly: bilateral, lobulated, solid/mixed solid and cystic. Conclusion: On imaging, Krukenberg tumor should be suspected when bilateral solid, mixed solid and cystic, or predominantly cystic ovarian masses are seen in the presence of a known or suspected gastrointestinal primary malignancy. Krukenberg tumors should also be considered when a ovarian mass shows the so-called “lead vessel sign”[1-12-15].

A review of Radiological Imaging Features to ameliorate radiologists’ knowledge of Krukenberg Tumor (KT)

Object: Aim is to delineate the major radiological findings with US, CT and MR of the Krukenberg Tumor. Method: Revision of the literature. Introduction: A Krukenberg Tumor refers tipically to a gastrointestinal cancer that metastasizes to the ovaries; this tumor was named after Krukenberg, who originally described this pathologic condition of the ovaries in 1896. The prognosis of this tumor is uniformly poor.[1] Discussion: Krukenburg tumor (KT)is a metastatic malignancy of the ovary characterized by mucin-rich signet-ring adenocarcinoma that primarily arises from a gastrointestinal site in most cases and less commonly from other sites. Often these tumors are bilateral (over 80%), given their metastatic nature. The images of a Krukenberg Tumor highlight that the masses are mostly: bilateral, lobulated, solid/mixed solid and cystic. Conclusion: On imaging, Krukenberg Tumor should be suspected when bilateral solid, mixed solid and cystic, or predominantly cystic ovarian masses are seen in the presence of a known or suspected gastrointestinal primary malignancy. Krukenberg Tumors should also be considered when a ovarian mass shows the so-called “lead vessel sign”[1-12-15].

Clinicopathologic Features of Gastrointestinal Tract Langerhans Cell Histiocytosis

Gastrointestinal (GI) tract involvement by Langerhans cell histiocytosis (LCH) is rare and its clinicopathologic characteristics have only been described in case reports and small series. We reviewed hematoxylin and eosin and CD1a, S100, and Langerin immunohistochemical–stained slides from 47 patients with well-documented demographic and clinical findings. Our cases included 8 children and 39 adults, with a mean follow-up of 63 months. All pediatric patients had concurrent multisystem LCH, presented with GI symptoms, and showed nonpolypoid lesions. Seven (88%) showed multifocal GI disease, including 5 with multiple GI organ involvement. All sampled lesions from children exhibited infiltrative growth. More than half had died of the disease or manifested persistent LCH at last follow-up. Twenty-five of 39 (64%) adults had LCH involving only the GI tract (single system), with the remaining 14 (36%) exhibiting multisystem disease. Adult single-system GI LCH was typically encountered incidentally on screening/surveillance endoscopy (72%). Most exhibited isolated colorectal involvement (88%) as a solitary polyp (92%), with a well-demarcated/noninfiltrative growth pattern (70%), and excellent prognosis (100%). In comparison, adult patients with multisystem LCH more frequently presented with GI symptoms (92%, P < .001), noncolorectal GI site involvement (50%, P = .02), multifocal GI lesions (43%, P = .005), nonpolypoid lesions (71%, P < .001), infiltrative histologic growth pattern (78%, P = .04), and persistent disease (57%, P < .001). Adult patients with multisystem LCH appear to exhibit similar clinicopathologic features to those of pediatric patients. These results demonstrated that adults with single-system LCH involving the GI tract have an excellent prognosis, whereas multisystem LCH occurring at any age carries an unfavorable prognosis. High-risk features of GI LCH include pediatric age, GI symptomatology, noncolorectal GI involvement, multifocal GI disease, nonpolypoid lesions, and infiltrative growth pattern.

Emerging Technologies in Endocrine Drug Delivery: Innovations for Improved Patient Care.

Recent advancements in drug delivery systems for endocrine disorders have significantly improved patient outcomes by addressing the limitations of traditional methods such as oral tablets and injections. These innovations include non-invasive alternatives like inhaled insulin, which provides rapid absorption and better patient compliance, and robotic pills that deliver drugs directly to specific gastrointestinal sites, enhancing absorption and reducing side effects. Wearable artificial pancreas systems have revolutionized diabetes management by integrating continuous glucose monitoring with insulin pumps to automate blood glucose control. These systems demonstrate superior glycemic control and reduce hypoglycemic events. Additionally, smart insulin pens enhance diabetes care through dose tracking and real-time data sharing, improving accuracy and adherence. Microneedle patches offer a minimally invasive method for transdermal drug delivery, effectively administering hormones and therapeutic peptides without the pain and inconvenience of injections. These patches dissolve after use, eliminating biohazardous waste. Implantable devices provide long-term, controlled release of medications, significantly improving adherence and glycemic control of patients with diabetes. Hydrogels also offer new drug delivery options. This review examines these technologies' clinical efficacy, safety, advantages, and limitations, highlighting their potential to transform endocrine disorder management. Integrating advanced delivery systems marks a significant step towards personalized medicine, tailoring treatments to individual patient needs for better health outcomes.

A Case of Polyserositis, Chylous Ascites and Hepatitis Induced by Immune Checkpoint Inhibitors.

Oncological therapy with immune checkpoint inhibitors (ICPIs) is frequently associated with immune-related adverse events (irAEs) most involving cutaneous, gastrointestinal and pulmonary sites.

Self-reported exhaustion and a 4-item physical frailty index to predict the incidence of major complications after onco-geriatric surgery

BackgroundThe aim of this study was to analyze four pre-operative physical frailty indicators from a geriatric assessment (GA) independently and combined in a physical frailty index, in their ability to predict postoperative 30 d-complications. Materials and methodsIn this secondary analysis of data from the published PERATECS study (ClinicalTrials.gov: NCT01278537), the predictive value of four physical frailty indicators from a defined GA battery was examined with univariable and multivariate logistic regression models in a sample of 493 onco-geriatric surgical patients. The primary endpoint was incidence of major (Clavien–Dindo ≥ grade 2 [CD ≥ 2]) complications within 30 postoperative days.Predictors of the first model included self-reported exhaustion (SRE), body mass index (BMI), Timed Up-and-Go (TUG) and handgrip strength (HGS) independently, and a second model combined these four items as a Physical Frailty Index (4i-PFI). Both regression models were adjusted for age, gender, American Society of Anesthesiologists (ASA) status, tumor sites, duration of surgery time and Mini Nutritional Assessment (MNA) score. ResultsA total of 233 patients (47 %) developed CD ≥ 2 complications. In addition to ASA score, length of surgery, and gynecological and upper gastrointestinal tumor sites, the first model showed that SRE (OR 1.866) predicted CD ≥ 2 complications, but not TUG, BMI and HGS. In the second model, the 4i-PFI predicted CD ≥ 2 complications (OR pre-frail = 1.808, frail = 3.787). ConclusionsPhysical frailty indicators as SRE revealed a better ability to predict CD ≥ 2 complications than BMI, TUG and HGS. However, prediction of CD ≥ 2 complications was enhanced when these parameters were combined in a novel 4i-PFI.

Diversity and host interaction of the gut microbiota in specific pathogen-free pigs.

Pigs are widely used as animal models in various studies related to humans. The interaction between the gut microbiota and the host has significant effects on the host's health and disease status. However, although there have been many studies investigating the pig gut microbiota, the findings have been inconsistent due to variations in rearing conditions. Interactions between the gut microbiota and host have not been fully explored in pigs. Specific pathogen-free (SPF) pigs are ideal non-primate large animals to study the interactions between the gut microbiota and the host. In this study, we performed high-throughput sequencing analysis of the gut microbiota and the gut tissue transcriptome of six SPF pigs to provide a systematic understanding of the composition, function, and spatial distribution of gut microbiota in SPF pigs. We identified significant differences in microbial diversity and functionality among different gastrointestinal tract sites. Metagenomics data analysis revealed significant differences in alpha diversity and beta diversity of microbiota in different gastrointestinal sites of SPF pigs. Additionally, transcriptomic data indicated significant differences in gene expression as well as KEGG and GO functional enrichment between the small intestine and large intestine. Furthermore, by combining microbial metagenomics and host transcriptomics analyses, specific correlations were found between gut microbiota and host genes. These included a negative correlation between the TCN1 gene and Prevotella dentalis, possibly related to bacterial metabolic pathways involving vitamin B12, and a positive correlation between the BDH1 gene and Roseburia hominis, possibly because both are involved in fatty acid metabolism. These findings lay the groundwork for further exploration of the co-evolution between the microbiota and the host, specifically in relation to nutrition, metabolism, and immunity. In conclusion, we have elucidated the diversity of the gut microbiota in SPF pigs and conducted a detailed investigation into the interactions between the gut microbiota and host gene expression. These results contribute to our understanding of the intricate dynamics between the gut microbiota and the host, offering important references for advancements in life science research, bioproduct production, and sustainable development in animal husbandry.

Low rumen degradable starch reduces diarrhea and colonic inflammation by influencing the whole gastrointestinal microbiota and metabolite flow in dairy goats

Postruminal intestinal inflammation and hindgut acidosis caused by increased dietary starch supply and thereby increased quantities of ruminal degradable starch (RDS) in ruminants have been widely studied. Although the roles of the microbiota in mediating hindgut health that are focused on the hindgut have been widely studied, the absence of whole gastrointestinal insight may influence the depth of research. We integrated the microbiome, metabolome, and host transcriptome changes in the rumen, jejunum, ileum, and colon to investigate the contributions of foregut changes to hindgut gene expression driven by gastrointestinal microbiota and metabolite flow. Forty goats were randomly assigned to receive either a low rumen degradable starch diet (LRDS, RDS=13.85%, n=20) or a high rumen degradable starch diet (HRDS, RDS=20.74%, n=20). Compared with the high RDS (HRDS) group, the low RDS (LRDS) group significantly decreased the diarrheal rate. Based on the mean values of the fecal scores, 6 represented goats of LRDS group (fecal scores=4.58±0.120) and 6 represented goats of HRDS group (fecal scores=3.53±0.343) were selected for sampling and subsequent analysis. LRDS had significantly decreased the colonic pathologic scores. Transcriptomic analysis revealed that LRDS reduced jejunal, ileal, and colonic inflammatory responses. An increase in beneficial commensals and a decreased abundance of pathogenic genera in the small intestine and hindgut were found in goats fed the LRDS diet using 16S rRNA gene sequencing. To identify microbial transmission as well as the transmission of microbial metabolites, 8 genera were identified as core genera according to their calculated niche width. Metabolomics analysis revealed that a total of 554 metabolites were identified among different gastrointestinal sites. Then, metabolites were incorporated into 3 modules: metabolites increased in the current site (ICS), unchanged inflow metabolites in the current site (UICS), and metabolites decreased in the current site (DCS). The results indicated that the UICS metabolites contributed more than 10% to host gene expression in the jejunum, ileum, and colon. When we further focused on the effects of colonic UICS metabolites on the colonic immune-related differentially expressed genes, the results indicated that 1-palmitoylglycerol and deoxycholic acid contributed 60.74% and 11.5% to the colonic immune-related differentially expressed genes, respectively. Our findings provide a preliminary framework of microbial effects that includes the microbiota and their metabolite changes, especially reduced 1-palmitoylglycerol and deoxycholic acid, in the former gastrointestinal tract that could be involved in the alleviation of colonic inflammation in goats fed LRDS diets.

Genomic characteristics of clinical non-toxigenic Vibrio cholerae isolates in Switzerland: a cross-sectional study.

Although non-toxigenicVibrio choleraelack thectxABgenes encoding cholera toxin, they can cause diarrhoeal disease and outbreaks in humans. In Switzerland,V. choleraeis a notifiable pathogen and all clinical isolates are analysed at the National Reference Laboratory for Enteropathogenic Bacteria and Listeria. Up to 20 infections are reported annually. In this study, we investigated the population structure and genetic characteristics of non-toxigenicV. choleraeisolates collected over five years. V. choleraeisolates were serotyped and non-toxigenic isolates identified using actxA-specific PCR. Following Illumina whole-genome sequencing, genome assemblies were screened for virulence and antibiotic resistance genes. Phylogenetic analyses were performed in the context of 965 publicly availableV. choleraegenomes. Out of 33V. choleraeinfections reported between January 2017 and January 2022 in Switzerland, 31 were caused byctxA-negative isolates. These non-toxigenic isolates originated from gastrointestinal (n = 29) or extraintestinal (n = 2) sites. They were phylogenetically diverse and belonged to 29 distinct sequence types. Two isolates were allocated to the lineage L3b, actxAB-negative buttcpA-positive clade previously associated with regional outbreaks. The remaining 29 isolates were placed in lineage L4, which is associated with environmental strains. Genes or mutations associated with reduced susceptibility to the first-line antibiotics fluoroquinolones and tetracyclines were identified in 11 and 3 isolates, respectively. One isolate was predicted to be multidrug resistant. V. choleraeinfections in Switzerland are rare and predominantly caused by lowly virulentctxAB-negative andtcpA-negative strains. AsV. choleraeis not endemic in Switzerland, cases are assumed to be acquired predominantly during travel. This assumption was supported by the phylogenetic diversity of the analysed isolates.

Gastrointestinal release site for delayed release and gelatin capsules in healthy dogs.

Gelatin capsules deliver their contents to the stomach, while delayed-release (DR) capsules are designed to allow delivery to the small intestine. This study evaluated the gastrointestinal release site of DR capsules in six healthy adult dogs compared to gelatin capsules. Both gelatin and DR capsules were filled with barium-impregnated polyethylene spheres (BIPS™), and following enteral administration, release site was assessed using abdominal radiographs at baseline, immediately after ingestion, 15 min post-ingestion, 30 min post-ingestion, and then every 30 min thereafter. The evaluated phases included fasted conditions (phase 1, n = 6), increased meal size (phase 2, n = 2), double encapsulation (phase 3, n = 2), and altered capsule size (phase 4, n = 1). The released site was the stomach in all phases for both capsule types. In phase 1, DR capsules had a significantly prolonged time (median 60 min, range 60-90) to release BIPS™ compared to gelatin capsules (15 min, range 15-30; p = .03). In phase 2 (full meal size), 3 (double encapsulation), and 4 (smaller capsule size) pilot studies, release time was prolonged but still occurred in the stomach. This is similar to the release site for gelatin capsules but differs from the release site for DR capsules in people. This has implications for pharmacologic outcomes for products that are affected by gastric physiology (e.g. fecal microbiota transplantation). Based on this pilot data, clinicians and researchers should not assume DR capsules will allow for intestinal delivery of contents in dogs. Future studies should be conducted on larger and varied populations of dogs.

The Royal College of Radiologists National Vulvar Cancer Audit

AimsThis audit examined UK vulvar cancer practice from March 2018 to January 2019 and compared it to standards from national and international recommendations. Follow-up data collection in 2020 examined patient outcomes and toxicity. Materials and methodsAudit standards were based on Royal College of Radiologists (RCR) guidance and published literature. A web-based questionnaire was sent to the audit leads at all cancer centres in the UK. Prospective data collection included patient demographics, tumour characteristics, radiotherapy indications, dosimetry, timelines, and follow-up data. The audit targets were 95% compliance with the RCR dose/fractionation schemes in definitive and adjuvant patients, 40% use of intensity modulated radiotherapy (IMRT), 100% of radical patients treated as category 1, and 95% use of gap compensation for category 1 patients. Results34/54 UK radiotherapy centres (63%) completed data entry for 152 patients. 23 out of 34 (68%) centres submitted follow-up data for 94 patients. One indicator exceeded the audit target: 98% of radical patients received IMRT. The indicators of RCR dose/fractionation compliance for adjuvant/definitive radiotherapy were achieved by 80%/43% for the primary, 80%/86% for elective lymph nodes, and 21%/21% for pathological lymph nodes. The use of concomitant chemotherapy with radical radiotherapy in suitable patients was achieved by 71%. Other indicators demonstrated that 78% were treated as category 1 and 27% used gap compensation. Acute toxicity was mostly related to skin, gastrointestinal, and genitourinary sites. Grade 3 and Grade 4 toxicities were seen at acceptable rates within the radical and adjuvant groups. Late toxicity was mostly grade 0. ConclusionThis audit provides a comprehensive picture of UK practice. IMRT is widely used in the UK, and treatment-related toxicity is moderate. The dose fractionation was very heterogeneous. The designation of vulvar cancer as category 1 was not regularly followed for radical/adjuvant patients, and there was minimal gap compensation during treatment.

Optimizing Gantry Breakpoint Angles in Proton Therapy: Enhancing Efficiency and Patient Experience

PurposeThe breakpoint for a 360° radiotherapy gantry is typically positioned at 180°. This arbitrary setting has not been systematically evaluated for efficiency and may cause redundant gantry rotation and extended setup times. Our study aimed to identify an optimal gantry breakpoint angle for a full-gantry proton therapy system, with the goal of minimizing gantry movement. Materials and MethodsWe analyzed 70 months of clinically delivered proton therapy plans (9152 plans, 131 883 fractions), categorizing them by treatment site and mapping the fields from a partial-gantry to full-gantry orientation. For each delivered fraction, we computed the minimum total gantry rotation angle as a function of gantry breakpoint position, which was varied between 0° and 360° in 1° steps. This analysis was performed separately within the entire plan cohort and individual treatment sites, both with and without the capability of over-rotating 10° past the breakpoint from either direction (20° overlap). The optimal gantry breakpoint was identified as one which resulted in a low average gantry rotation per fraction. ResultsConsidering mechanical constraints, 130° was identified as a reasonable balance between increased gantry-rotation efficiency and practical treatment considerations. With a 20° overlap, this selection reduced the average gantry rotation by 41.4° per fraction when compared to the standard 180° breakpoint. Disease site subgroups showed the following reduction in average gantry rotation: gastrointestinal 192.2°, thoracic 56.3°, pediatric 44.9°, genitourinary 19.9°, central nervous system 10.7°, breast 2.8°, and head and neck 0.1°. ConclusionFor a full-gantry system, a breakpoint of 130° generally outperforms the conventional 180° breakpoint. This reduction is particularly impactful for gastrointestinal, pediatric, and thoracic sites, which constitute a significant proportion of cases at our center. The adjusted breakpoint could potentially streamline patient delivery, alleviate mechanical wear, and enhance treatment precision by reducing the likelihood of patient movement during delivery.

Effect of Hypotension and Dobutamine on Gastrointestinal Microcirculations of Healthy, Anesthetized Horses.

Horses undergoing abdominal exploratory surgery are at risk of hypotension and hypoperfusion. Normal mean arterial pressure is used as a surrogate for adequate tissue perfusion. However, measures of systemic circulation may not be reflective of microcirculation. This study measured the mean arterial pressure, cardiac index, lactate, and four microcirculatory indices in six healthy, anesthetized adult horses undergoing elective laparotomies. The microcirculatory parameters were measured at three different sites along the gastrointestinal tract (oral mucosa, colonic serosa, and rectal mucosa) with dark-field microscopy. All macro- and microcirculatory parameters were obtained when the horses were normotensive, hypotensive, and when normotension returned following treatment with dobutamine. Hypotension was induced with increases in inhaled isoflurane. The horses successfully induced into hypotension did not demonstrate consistent, expected changes in systemic perfusion or microvascular perfusion parameters at any of the three measured gastrointestinal sites. Normotension was successfully restored with the use of dobutamine, while the systemic perfusion and microvascular perfusion parameters remained relatively unchanged. These findings suggest that the use of mean arterial pressure to make clinical decisions regarding perfusion may or may not be accurate.