Occurrence of multi-carbapenemase-producing Enterobacterales in a tertiary hospital in Madrid (Spain): a new epidemiologic scenario.

INTRODUCTION: Multi-carbapenemase-producing Enterobacterales (M-CPE) are increasingly described. We characterized the M-CPE isolates prospectively recovered in our hospital (Madrid, Spain) over two years (2021-2022). METHODS: We collected 796 carbapenem resistant Enterobacterales (CRE) from clinical and surveillance samples. Carbapenemase production was confirmed with phenotypic (immunochromatographic, disk diffusion) and molecular (PCR, WGS) techniques. Antimicrobial susceptibility was evaluated by a standard broth microdilution method. Clinical and demographic data were collected. RESULTS: Overall, 23 M-CPE (10 Klebsiella pneumoniae, 6 Citrobacter freundii complex, 3 Escherichia coli, 2 Klebsiella oxytoca, and 2 Enterobacter hormaechei) isolates were recovered from 17 patients (3% with CPE, 0.27 cases per 1000 admissions). OXA-48+KPC-3 (7/23) and KPC-3+VIM-1 (5/23) were the most frequent carbapenemase combinations. All patients had prior antibiotics exposure, including carbapenems (8/17). High resistance rates to ceftazidime/avibactam (14/23), imipenem/relebactam (16/23) and meropenem/vaborbactam (7/23) were found. Ceftazidime/avibactam+aztreonam combination was synergistic in all metallo-ß-lactamase producers. Clonal and non-clonal related isolates were found, particularly in K. pneumoniae (5 ST29, 3 ST147, 3 ST307) and C. freundii (3 ST8, 2 ST125, 1 ST563). NDM-1+OXA-48 was introduced with the ST147-K. pneumoniae high-risk clone linked to the transfer of an Ukrainian patient. We identified four possible nosocomial clonal transmission events between patients of the same clone with the same combination of carbapenemases (KPC-3+VIM-1-ST29-K. pneumoniae, NDM-1+OXA-48-ST147-K. pneumoniae and KPC-2+VIM-1-ST145-K. oxytoca). Carbapenemase-encoding genes were located on different plasmids, except for VIM-1+KPC-2-ST145-K. oxytoca. Cross-species transmission and a possible acquisition overtime was found, particularly between K. pneumoniae and E. coli producing OXA-48+KPC-3. CONCLUSION: M-CPE is an emerging threat in our hospital. Co-production of different carbapenemases, including metallo-ß-lactamases, limits therapeutic options and depicts the need to reinforce infection control measures.

Effect of Tumor Regression Grade on Survival and Disease-Free Interval in Patients Operated on for Locally Advanced Rectal Cancer.

INTRODUCTION: Colorectal cancer is the fourth leading cause of cancer-related death in both men and women in our population. In this regard, rectal cancer accounts for more than half of colorectal cancer deaths, and its incidence is expected to increase in the coming years. There have been significant changes in neoadjuvant therapy regimens, with promising results, as demonstrated by the recent RAPIDO and PRODIGE23 studies. Around 40% of patients diagnosed with locally advanced rectal cancer show some degree of response to neoadjuvant treatment, with complete tumor regression observed in up to one in five patients. MATERIALS AND METHODS: Retrospective observational study. A total of 181 patients with locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy followed by surgery were analyzed. Clinical and pathological data were collected from the patients, including assessment of tumor regression through histopathological studies after surgery. The Mandard tumor regression grading system was used to categorize tumor response into different grades. RESULTS: The results showed a significant association between the degree of tumor regression and several important clinical outcomes. Specifically, patients with higher tumor regression had significantly better disease-free survival than those with less regression (p = 0.004). In addition, tumor regression was also correlated with the incidence of local recurrence (p = 0.018) and distant metastasis (p = 0.032). These associations suggest that tumor responsiveness to neoadjuvant therapy may influence the long-term progression of the disease. Regarding tumor deposits and the presence of lymphadenopathy, these factors were also found to be significantly associated with clinical outcomes. Patients with tumor deposits had a higher incidence of local recurrence (p = 0.025) and distant metastases (p = 0.041), while the presence of lymphadenopathy increased the risk of local recurrence (p = 0.013). These findings highlight the importance of evaluating not only tumor regression but also other pathological markers to predict prognosis and guide clinical management. CONCLUSIONS: The degree of tumor regression was not an independent predictor of survival compared to other variables such as nodal stage and presence of tumor deposits. This indicates that while tumor regression is an important factor, other elements also play a crucial role in determining the prognosis of patients with locally advanced rectal cancer. This study provides additional evidence for the importance of tumor regression, tumor deposits, and lymphadenopathy as predictors of clinical outcomes in patients with rectal cancer treated with neoadjuvant chemoradiotherapy.

Therapeutic potential of oleic acid supplementation in myotonic dystrophy muscle cell models.

BACKGROUND: We recently reported that upregulation of Musashi 2 (MSI2) protein in the rare neuromuscular disease myotonic dystrophy type 1 contributes to the hyperactivation of the muscle catabolic processes autophagy and UPS through a reduction in miR-7 levels. Because oleic acid (OA) is a known allosteric regulator of MSI2 activity in the biogenesis of miR-7, here we sought to evaluate endogenous levels of this fatty acid and its therapeutic potential in rescuing cell differentiation phenotypes in vitro. In this work, four muscle cell lines derived from DM1 patients were treated with OA for 24 h, and autophagy and muscle differentiation parameters were analyzed. RESULTS: We demonstrate a reduction of OA levels in different cell models of the disease. OA supplementation rescued disease-related phenotypes such as fusion index, myotube diameter, and repressed autophagy. This involved inhibiting MSI2 regulation of direct molecular target miR-7 since OA isoschizomer, elaidic acid (EA) could not cause the same rescues. Reduction of OA levels seems to stem from impaired biogenesis since levels of the enzyme stearoyl-CoA desaturase 1 (SCD1), responsible for converting stearic acid to oleic acid, are decreased in DM1 and correlate with OA amounts. CONCLUSIONS: For the first time in DM1, we describe a fatty acid metabolism impairment that originated, at least in part, from a decrease in SCD1. Because OA allosterically inhibits MSI2 binding to molecular targets, reduced OA levels synergize with the overexpression of MSI2 and contribute to the MSI2 > miR-7 > autophagy axis that we proposed to explain the muscle atrophy phenotype.

Thyroid abscess, an uncommon diagnosis: A case report and mini­review of the literature.

Thyroid abscess is a rare entity, commonly experienced by immunocompromised patients, or those who have anatomical abnormalities or a pre-existing thyroid disease. An early diagnosis continued by treatment with antibiotics and drainage of the abscess is the recommended therapeutic strategy for such cases. The present study describes a clinical case of this rare event, and also provides a brief literature review. The present study describes the case of a 48-year-old healthy male with no medical antecedents, apart from acute prostatitis treated with antibiotics for 6 days prior, who visited the Emergency Department of the authors' hospital with neck pain and progressive swelling of the mass. Diagnostic imaging confirmed the authors' suspicion of an abscess and revealed the lesion displacing the airway to the contralateral side. This restricted the mobility of the neck of the patient. As an emergency measure, the patient was then taken to the operating room for a neck examination. A hemithyroidectomy was finally performed. Following a prolonged hospital duration, he was discharged from the hospital and his recovery was uneventful without any voice alterations, hypocalcemia or recurrence.

Dynamics of Gut Microbiota and Short-Chain Fatty Acids during a Cycling Grand Tour Are Related to Exercise Performance and Modulated by Dietary Intake.

BACKGROUND: Regular exercise has been described to modify both the diversity and the relative abundance of certain bacterial taxa. To our knowledge, the effect of a cycling stage race, which entails extreme physiological and metabolic demands, on the gut microbiota composition and its metabolic activity has not been analysed. OBJECTIVE: The aim of this cohort study was to analyse the dynamics of faecal microbiota composition and short-chain fatty acids (SCFAs) content of professional cyclists over a Grand Tour and their relationship with performance and dietary intake. METHODS: 16 professional cyclists competing in La Vuelta 2019 were recruited. Faecal samples were collected at four time points: the day before the first stage (A); after 9 stages (B); after 15 stages (C); and on the last stage (D). Faecal microbiota populations and SCFA content were analysed using 16S rRNA sequencing and gas chromatography, respectively. A principal component analysis (PCA) followed by Generalised Estimating Equation (GEE) models were carried out to explore the dynamics of microbiota and SCFAs and their relationship with performance. RESULTS: Bifidobacteriaceae, Coriobacteriaceae, Erysipelotrichaceae, and Sutterellaceae dynamics showed a strong final performance predictive value (r = 0.83, ranking, and r = 0.81, accumulated time). Positive correlations were observed between Coriobacteriaceae with acetate (r = 0.530) and isovalerate (r = 0.664) and between Bifidobacteriaceae with isobutyrate (r = 0.682). No relationship was observed between SCFAs and performance. The abundance of Erysipelotrichaceae at the beginning of La Vuelta was directly related to the previous intake of complex-carbohydrate-rich foods (r = 0.956), while during the competition, the abundance of Bifidobacteriaceae was negatively affected by the intake of simple carbohydrates from supplements (r = -0.650). CONCLUSIONS: An ecological perspective represents more realistically the relationship between gut microbiota composition and performance compared to single-taxon approaches. The composition and periodisation of diet and supplementation during a Grand Tour, particularly carbohydrates, could be designed to modulate gut microbiota composition to allow better performance.

Clinical Applications of "In-Hospital" 3D Printing in Hip Surgery: A Systematic Narrative Review.

Introduction: Interest in 3D printing for orthopedic surgery has been increasing since its progressive adoption in most of the hospitals around the world. The aim of the study is to describe all the current applications of 3D printing in patients undergoing hip surgery of any type at the present time. Materials and Methods: We conducted a systematic narrative review of publications indexed in MedLine through the search engine PubMed, with the following parameters: 3D printing AND (orthopedics OR traumatology) NOT tissue engineering NOT scaffold NOT in vitro and deadline 31 July 2023. After reading the abstracts of the articles, papers were selected according to the following criteria: full text in English or Spanish and content related to hip surgery. Those publications involving experimental studies (in vitro or with anatomical specimens) or 3D printing outside of hospital facilities as well as 3D-printed commercial implants were excluded. Results are presented as a reference guide classified by disease, including the used software and the steps required for the development of the idea. Results: We found a total of 27 indications for in-house 3D printing for hip surgery, which are described in the article. Conclusions: There are many surgical applications of 3D printing in hip surgery, most of them based on CT images. Most of the publications lack evidence, and further randomized studies should be encouraged to assess the advantages of these indications.

Single metachronous bone metastasis following rectal adenocarcinoma: A case report.

Colorectal cancer (CRC) ranks as the third leading cause of cancer-related mortality in developed countries. While its incidence in early stages has increased due to screening programs, a significant number of patients experience the development of metastases either at the time of diagnosis or during follow-ups. Unlike certain other types of cancer, such as breast, prostate, or lung cancer, where bone tissue is a common site for secondary dissemination, CRC primarily spreads to the lymph nodes, liver and lungs. The occurrence of bone metastases from CRC is rare and usually coincides with tumor involvement in other locations. Risk factors for bone metastases include the location of the primary tumor, the age of the patients, KRAS mutations and the degree of tumor differentiation. Unlike metastases to the liver and lungs, bone metastases tend to be symptomatic, affecting the patient's quality of life and resulting in a poorer prognosis with shorter survival rates. The approach to patient management needs to be personalized. The present study describes the of a patient who underwent surgery for stage IV rectal adenocarcinoma and later developed a metastasis in the costal wall 79 months post-intervention, with no evidence of recurrence at other sites.

Importance of three physiological models for teaching the carbohydrates metabolism.

In this work extensive misconceptions of university students' -from nutrition area- about the metabolism of carbohydrates (CHM) in the human organism have been documented. The results lead to consider their difficulties concerning the learning of a complex set of imbricated biochemical models involved. Pursuant to these considerations, three physiological models are proposed as conceptual axes around which CHM in the human organism could be taught, in order to avoid fragmentation in students' knowledge and to give simple physiological contexts where to integrate those biochemical models. These contexts are: (a) a physiological model of the carbon cycle, (b) a physiological model of blood glucose uptake and homeostasis, and (c) a physiological model of the availability of small metabolites.

Therapeutic potential of oleic acid supplementation in myotonic dystrophy muscle cell models

Background We recently reported that upregulation of Musashi 2 (MSI2) protein in the rare neuromuscular disease myotonic dystrophy type 1 contributes to the hyperactivation of the muscle catabolic processes autophagy and UPS through a reduction in miR-7 levels. Because oleic acid (OA) is a known allosteric regulator of MSI2 activity in the biogenesis of miR-7, here we sought to evaluate endogenous levels of this fatty acid and its therapeutic potential in rescuing cell differentiation phenotypes in vitro. In this work, four muscle cell lines derived from DM1 patients were treated with OA for 24 h, and autophagy and muscle differentiation parameters were analyzed. Results We demonstrate a reduction of OA levels in different cell models of the disease. OA supplementation rescued disease-related phenotypes such as fusion index, myotube diameter, and repressed autophagy. This involved inhibiting MSI2 regulation of direct molecular target miR-7 since OA isoschizomer, elaidic acid (EA) could not cause the same rescues. Reduction of OA levels seems to stem from impaired biogenesis since levels of the enzyme stearoyl-CoA desaturase 1 (SCD1), responsible for converting stearic acid to oleic acid, are decreased in DM1 and correlate with OA amounts. Conclusions For the first time in DM1, we describe a fatty acid metabolism impairment that originated, at least in part, from a decrease in SCD1. Because OA allosterically inhibits MSI2 binding to molecular targets, reduced OA levels synergize with the overexpression of MSI2 and contribute to the MSI2 > miR-7 > autophagy axis that we proposed to explain the muscle atrophy phenotype.

First detection in Spain of NDM-1-producing Pseudomonas aeruginosa in two patients transferred from Ukraine to a university hospital.

OBJECTIVES: Carbapenemase-mediated carbapenem resistance in Pseudomonas aeruginosa is a relevant health problem. We detected for the first time in Spain two clinical NDM-producing P. aeruginosa (NDM-Pa) isolates in two Ukrainian patients admitted to our hospital between April and August 2022. METHODS: Antimicrobial susceptibility was studied by microdilution and MIC gradient strips (EUCAST-2022 criteria). Carbapenemase genes were detected by the Xpert Carba-R and immunochromatography assays. WGS (Illumina and Oxford-Nanopore) was also performed. RESULTS: In May 2022, we detected an NDM-Pa in a sternotomy wound in a patient. In June-2022, a second NDM-Pa along with an OXA-48-Klebsiella pneumoniae (OXA-48-Kp) isolate was detected in a mandibular abscess from an unrelated patient. Moreover, an NDM+OXA-48-K. pneumoniae (NDM+OXA-48-Kp) was also found in a rectal sample of this patient. Both patients had undergone surgery in Ukraine before their transfer to our hospital. NDM-Pa isolates were resistant to all tested antimicrobials with the exception of aztreonam (MIC = 8 mg/L), colistin (MIC =2 mg/L) and cefiderocol (MIC range = 0.75-2 mg/L). WGS confirmed that both P. aeruginosa isolates were NDM-1 producers, belonged to ST773 and shared an identical resistome. blaNDM-1 was located on a ∼117-Kb chromosomally integrated integrative conjugative element (ICE). OXA-48-Kp and NDM+OXA-48-Kp belonged to ST147 and contained blaOXA-48 on an identical ∼300-Kb IncHIB-plasmid. blaNDM-1 was located on a 51-Kb IncFIB-plasmid only found in NDM+OXA-48-Kp. CONCLUSIONS: This is the first description of NDM-Pa in Spain. We highlight the threat of further cross-border dissemination of NDM-1 through P. aeruginosa along with K. pneumoniae high-risk clones also carrying OXA-48, which draws a complex epidemiological scenario.

Spontaneous cervical hematoma caused by giant parathyroid adenoma in an elderly patient: A case report.

Spontaneous cervical hematoma usually occurs as a consequence of extracapsular bleeding from a parathyroid gland, generally due to the presence of an adenoma (giant adenoma), glandular hyperplasia, cystic component, or, less frequently, due to the existence of a carcinoma. The hematoma can be confined to the cervical compartment or extend to the mediastinum, potentially causing airway compression. Despite this, the recommended management in hemodynamically stable patients consists of surveillance and hospital monitoring with delayed surgery after a few weeks. On the other hand, in those patients with airway compromise and instability, emergency surgery, consisting of cervicotomy and drainage, is mandatory. The present study describes the case of a 78-year-old patient with a medical history of high blood pressure, non-insulin-dependent diabetes mellitus, dyslipidemia, moderate aortic stenosis, chronic kidney disease and sarcoidosis under pharmacological treatment who attended the emergency department due to symptoms of neck pain, an increase in soft tissue, and dyspnea on moderate exertion with an evolution leading to respiratory failure. This was secondary to a diagnosis of spontaneous cervical hematoma that required urgent surgical intervention. The results of histopathological analysis revealed that a giant parathyroid adenoma was responsible for the bleeding. The patient had a complicated post-operative period with a prolonged admission to the intensive care unit.

Peritoneal Metastases: Evolution from a Dark Horizon to an Encouraging Present and a Promising Future.

Peritoneal metastasis (PM) is the primary pattern of metastasis for primary tumours of the appendix, ovary, and peritoneal mesothelioma [...].

Malignant Bowel Obstruction Due to Intraluminal Metastasis of Endometrial Adenocarcinoma Located in the Sigmoid Colon After Nine Years of Follow-Up.

Endometrial adenocarcinoma is currently the most common malignant tumor of the female genital tract. In the early stages, surgical or radiotherapy treatment offers high survival rates and excellent prognosis, although late recurrences have been described. Recurrences of endometrial adenocarcinoma are more frequent in the vaginal vault; however, implants are sometimes detected in the serosa of the colon and rectum, resulting in extrinsic compression. Here, we present the case of a 77-year-old patient with a clinical history of hysterectomy, lymphadenectomy, and double adnexectomy for endometrial adenocarcinoma (International Federation of Gynecology and Obstetrics (FIGO) Ia). Nine years after the initial treatment, she presented an endoluminal recurrence in the sigmoid colon, which is exceptional. The patient underwent surgery by performing an oncological sigmoidectomy. The immunohistochemical study revealed the tumor origin as metastasis of endometrial adenocarcinoma. The patient had a favorable postoperative period, subsequently receiving adjuvant therapy and being disease-free after 18 months of follow-up.

Scanning Electron Microscopy and EDX Spectroscopy of Commercial Swabs Used for COVID-19 Lateral Flow Testing.

The chemical composition of COVID test swabs has not been examined beyond the manufacturer's datasheets. The unprecedented demand for swabs to conduct rapid lateral flow tests and nucleic acid amplification tests led to mass production, including 3D printing platforms. Manufacturing impurities could be present in the swabs and, if so, could pose a risk to human health. We used scanning electron microscopy and energy dispersive X-ray (EDX) spectroscopy to examine the ultrastructure of seven assorted brands of COVID test swabs and to identify and quantify their chemical elements. We detected eight unexpected elements, including transition metals, such as titanium and zirconium, the metalloid silicon, as well as post-transition metals aluminium and gallium, and the non-metal elements sulphur and fluorine. Some of the elements were detected as trace amounts, but for others, the amount was close to reported toxicological thresholds for inhalation routes. Experimental studies have shown that the detrimental effects of unexpected chemical elements include moderate to severe inflammatory states in the exposed epithelium as well as proliferative changes. Given the massive testing still being used in the context of the COVID pandemic, we urge caution in continuing to recommend repeated and frequent testing, particularly of healthy, non-symptomatic, individuals.

Description of mpox reinfection by whole genome sequencing.

Several possible mpox reinfections have been reported, however, the debate on whether these are confirmed reinfections remains open. A 30-year-old male living with HIV and a history of single-dose mpox vaccination, first diagnosed with mpox in September 2022, presented with genital ulcers in March 2023, testing positive for mpox virus. Real-time polymerase chain reaction revealed the presence of viral DNA with cycle threshold values of 24 and 25, respectively. Whole genome sequencing and phylogenetic approach allowed us to classify these viruses as Clade IIb lineage B.1 and Clade IIb lineage B.1.4, respectively. Twelve nucleotide differences were identified. The observed difference was higher than the estimate of mutations/genome/year described. These data confirm that mpox reinfection is possible and reinforces current vaccination campaigns.

Gallbladder Volvulus in an Elderly Patient: A Case Report and Review of Literature.

Gallbladder volvulus is an uncommon cause of acute cholecystitis that results from the rotation of the gallbladder about its mesentery along the axis of the cystic pedicle. We present the case of an 87-year-old woman with acute abdominal pain in the right upper quadrant that began two days prior with no additional symptoms. The physical examination showed a large abdominal eventration on the right side and tenderness. A CT scan showed a distended gallbladder outside its liver bed and with a twist on its cystic pedicle, suggesting a gallbladder volvulus. Abdominal ultrasonography complementary revealed the gallbladder outside its vesicular fossa with incipient changes of acute cholecystitis but without evidence of gallstones. With the diagnosis of acute abdomen secondary to gallbladder volvulus, an emergency cholecystectomy was performed. The exact etiology of the gallbladder volvulus is unknown, although anatomical variants that predispose to its appearance have been described. The clinical presentation is similar to acute cholecystitis, so preoperative diagnosis can be challenging for both surgeons and radiologists and is often misdiagnosed. This is one of the few cases diagnosed with preoperative imaging techniques. Once diagnosed, the appropriate treatment is emergency cholecystectomy. Early diagnosis and surgical treatment are important before it progresses to necrosis, perforation, biliary peritonitis, and hemodynamic instability. Gallbladder volvulus is an uncommon condition. A high index of suspicion is required because the preoperative diagnosis is unusual. Once the diagnosis is established, the treatment is fundamentally surgical.

Msi2 enhances muscle dysfunction in a myotonic dystrophy type 1 mouse model.

BACKGROUND: Myotonic dystrophy type 1 (DM1) is a rare neuromuscular disease caused by a CTG repeat expansion in the 3' untranslated region of the DM1 protein kinase gene. Characteristic degenerative muscle symptoms include myotonia, atrophy, and weakness. We previously proposed an MSI2>miR-7>autophagy axis whereby MSI2 overexpression repressed miR-7 biogenesis that subsequently de-repressed muscle catabolism through excessive autophagy. Because the DM1 HSALR mouse model expressing expanded CUG repeats shows weak muscle-wasting phenotypes, we hypothesized that MSI2 overexpression was sufficient to promote muscle dysfunction in vivo. METHODS: By means of recombinant AAV murine Msi2 was overexpressed in neonates HSALR mice skeletal muscle to induce DM1-like phenotypes RESULTS: Sustained overexpression of the murine Msi2 protein in HSALR neonates induced autophagic flux and expression of critical autophagy proteins, increased central nuclei and reduced myofibers area, and weakened muscle strength. Importantly, these changes were independent of Mbnl1, Mbnl2, and Celf1 protein levels, which remained unchanged upon Msi2 overexpression. CONCLUSIONS: Globally, molecular, histological, and functional data from these experiments in the HSALR mouse model confirms the pathological role of Msi2 expression levels as an atrophy-associated component that impacts the characteristic muscle dysfunction symptoms in DM1 patients.

Differences in Colorectal Cancer Survival Based on Primary Tumor Location: Retrospective Study from a Single Institution.

Objective: The location of the primary tumor in colorectal cancer (CRC) could be a prognostic factor related to survival. However, its usefulness has not been sufficiently analyzed. The results in patients with tumors in initial stages are very limited, and there are descriptive parameters of survival that have not been analyzed in detail. In this study, the relationship between primary tumor location and survival in CRC patients was analyzed. Materials And Methods: This was a retrospective observational study. All patients treated consecutively for CRC between January 2005 and December 2019 in the same hospital center were included. Overall survival (OS), cancer-related survival (CRS), time to recurrence (TTR), relapse-free survival (RFS) and postrecurrence survival (PRS) were analyzed, and the results were classified by tumor stage. The results were compared among patients with right colon (RS), left colon (LS) and rectal tumors. Results: In the entire cohort, patients with RS tumors had lower OS and lower CRS at 60 months after diagnosis than did patients with LS or rectal tumors. In the regression analysis, the localization of the primary tumor was an independent prognostic indicator for OS and CRS. Analysis by tumor stage showed that patients with RS stage III tumors had lower OS and lower CRS at 60 months than did patients with LS and rectal tumors (42%, 59% and 53%, respectively, p = 0.006; and 48%, 63% and 57%, respectively, p = 0.025). Additionally, patients with RS Stage IV tumors had lower OS and lower CRS at 36 months than did patients with LS and rectal tumors (9%, 24%, 24%, respectively, p < 0.001; and 10%, 24% and 24%, respectively, p < 0.001). No differences were found in TTR and RFS among patients with stage I and II RS, LS, and rectal tumors. In contrast, patients with stage RS III tumors had significantly poorer PRS (9% for RS tumors, 13% for LS tumors, and 22% for rectal tumors) (p < 0.001). Conclusion: The location of the primary tumor in patients with CRC is related to survival. The effect of laterality is more marked in patients with stage III and IV tumors. Patients with RS tumors had lower OS and CRS due to the lower survival of patients with stage IV RS tumors and lower PRS for patients with stage III tumors.

Anastomotic leak in colorectal cancer surgery: Contribution of gut microbiota and prediction approaches.

AIM: To monitor prospectively the occurrence of colorectal anastomotic leakage (CAL) in patients with colon cancer undergoing resectional surgery, characterizing the microbiota in both faeces and mucosal biopsies of anastomosis. In a second stage, we investigated the ability to predict CAL using machine learning models based on clinical data and microbiota composition. METHOD: A total of 111 patients were included, from whom a faecal sample was obtained, as well as biopsy samples from proximal and distal sites in the healthy margins of the tumour piece. The microorganisms present in the samples were investigated using microbial culture and 16S rDNA massive sequencing. Collagenase and protease production was determined, as well as the presence of genes responsible for expressing enzymes with these activities. Machine learning analyses were developed using clinical and microbiological data. RESULTS: The incidence of CAL was 9.0%, and CAL was associated with collagenase/protease-producing Enterococcus. Significant differences were found in the microbiota composition of proximal and distal biopsy samples, but not in faecal samples, among patients who developed CAL. Clinical predictors of CAL were 5-day C-reactive protein and heart disease, whereas 3-day C-reactive protein and diabetes were negative predictors. CONCLUSION: Biopsy samples from surgical margins, rather than faecal samples, are the most appropriate samples for exploring the contribution of the intestinal microbiota to CAL. Enterococci are only enriched in the anastomosis after surgery, and their collagenases and proteases are involved in the degradation of the anastomotic scar.