Left Colon Research Articles

Acute Intussusception on a Lipoma of the Left Colon in an Adult

Acute Intussusception on a Lipoma of the Left Colon in an Adult

Incidental Uptake in Gastrointestinal Tract on 18F-FDG-PET/CT: Is It Worth to Investigate? A Study with 371 Patients

Background and Study Aims: Positron emission tomography/computed tomography (PET/CT) with 2-[18F]FDG (FDG) has been increasingly used to detect or monitor neoplasms. Gastrointestinal tract (GIT) is one of the most common sites of FDG uptake, leading to increasing requests for endoscopic examinations. We aimed to evaluate the nature and significance of unexpected PET/CT-FDG findings in the GIT. Patients and Methods: We retrospectively analyzed 371 consecutive patients with incidental GIT findings on PET/CT-FDG between June 2016 and October 2021 who were subsequently referred to endoscopic examinations. Demographic data, PET/CT-FDG results, endoscopic findings, and histological analysis were analyzed. Results: Of 194 colonic incidental uptakes, 102 (52.6%) corresponded to at least premalignant lesions, being 57 (29.4%) advanced adenomas and 23 (11.9%) adenocarcinomas. Of 193 upper GIT incidental uptakes, there were 11 (13.8%) esophageal and 14 (14.4%) gastric malignant/premalignant lesions. The maximum standardized uptake value (SUVmax) significantly varied according to the nature of the lesion, being higher in malignant lesions (in the esophagus, stomach, and colon). However, an optimal SUVmax cutoff was only found for stomach (SUVmax 8.2; sensitivity of 79% and specificity of 76%). There was a significant association between the site of uptake and the nature of the lesion – left colon and gastric body uptake were associated with neoplastic origin whereas rectum and lower esophagus were associated with inflammatory or no endoscopic changes. Conclusions: Any incidental uptake in the lower GIT should be investigated provided that patients are suitable for further treatment. However, in the upper GIT the characteristics of uptake on 18F‐FDG‐PET/CT may allow to select those who need endoscopic examination.

From evidence to practice: real-world insights into outpatient management of acute uncomplicated diverticulitis.

Diverticulitis is experiencing a significant increase in prevalence and its widespread in-hospital management results in a high burden on healthcare systems worldwide. This study compared inpatient and outpatient approach of acute non-complicated diverticulitis using a non-selected population in a real-world setting. This observational retrospective study included all consecutive patients from two Portuguese institutions diagnosed between January 2017 and December 2021 with non-complicated diverticulitis according to the modified Hinchey Classification. The primary endpoints were to identify criteria for inpatient treatment and compare the outcomes on the basis of the treatment regimen. The secondary endpoints were to determine the predictive factors for clinical outcomes, focusing on treatment failure, pain recurrence, and the need for elective surgery following the initial episode. A total of 688 patients were included in this study, 437 treated as outpatients and 251 hospitalized. Inpatient management was significantly associated with higher preadmission American society of anesthesiologists (ASA) score (p = 0.004), fever (p = 0.030), leukocytosis (p < 0.001), and elevated C-reactive protein (CRP) (p < 0.001). No significant association was found between failure of conservative treatment and patient's age, ASA score, baseline CRP, presence of systemic inflammatory response syndrome (SIRS), and inpatient or outpatient treatment regimen. Pain recurrence was significantly associated with higher CRP levels (p = 0.049), inpatient treatment regime (p = 0.009) and post index episode mesalazine prescription (p = 0.006). Moreover, the need for elective surgery was significantly associated with the presence of previous episodes (p = 0.004) and pain recurrence (p < 0.001). The majority of patients with uncomplicated diverticulitis of the left colon experience successful conservative approach and can be safely managed in an ambulatory setting. Neither treatment failure, recurrence of pain, or need for posterior elective surgery are associated with outpatient treatment regimen.

INDOCYANINE GREEN IN LEFT SIDE COLORECTAL SURGERY SEGMENTAL RESECTION TO DECREASE ANASTOMOTIC LEAK: A PARALLEL RETROSPECTIVE COHORT STUDY OF 115 PATIENTS

BackgroundWe investigated the impact of Indocyanine Green (ICG) angiography on reducing anastomotic leakage (AL) after elective left segmental colon resection, including transverse resection. While ICG is widely used in colorectal surgery to assess vascularization, its true effect on AL, particularly in left segmental resections, remains unclear. Study DesignThis retrospective, monocentric cohort study included patients undergoing left and transverse colon resection from January 2017 to July 2023. Patients were divided into ICG and no-ICG groups. The primary outcome was AL, with secondary outcomes including postoperative morbidity and length of stay. ResultsOf the 115 patients enrolled, 53 received ICG and 63 did not. AL occurred in 6 patients in the no-ICG group, but none in the ICG group. No significant correlation was found between ICG use and other confounding factors. Postoperative length of stay was also shorter in the ICG group. ConclusionsThe use of ICG was associated with a reduction in AL, with no cases in the ICG group. These findings suggest a potential benefit of ICG, warranting confirmation in future large-scale studies. Clinical trial registrationclinicaltrial.gov (NCT05981937)

Ki-67 distribution, α-methylacyl-CoA racemase (AMACR) expression and mucin phenotypes are associated with non-polypoid growth in ulcerative colitis-associated neoplasia.

Ulcerative colitis-associated neoplasia (UCAN) is characterised by multifocal tumourigenesis. A wide range of metachronous lesions have been reported to occur after endoscopic treatment of UCAN, which suggests the development of sporadic tumours in lesions treated as UCAN. Therefore, we aimed to evaluate differences of immunohistochemistry (IHC) in features and clinicopathological characteristics of intramucosal lesions in patients with ulcerative colitis (UC). We examined 35 intramucosal lesions resected for carcinoma or dysplasia by total colectomy from patients with UC and 71 sporadic adenomas (SAs) endoscopically resected from patients without UC. UC lesions were divided into the conventional UCAN group, defined as p53 mutant pattern andnormal expression of β-catenin, and the non-conventional UCAN group, defined as the rest. Ki-67 distribution, α-methylacyl-CoA racemase (AMACR) expression and mucin phenotypes were compared using IHC, and clinicopathological characteristics were investigated. Conventional and non-conventional UCAN lesions were located in the left colon and rectum. Relative to the SA lesions, UCAN lesions occurred in much younger patients and exhibited more frequent basal distribution of Ki-67 in tumour crypts. Conventional UCAN lesions tended to be non-polyploid and exhibited a higher frequency of normal AMACR expression than SA lesions. UC lesions were heterogeneous-only two of the eight patients with multiple lesions had lesions (both non-conventional UCAN lesions) exhibiting concordant IHC staining features. The basal pattern of Ki-67 distribution, normal expression of AMACR and a non-intestinal mucin phenotype were determined as characteristic features suggestive of UCAN. Non-polypoid growth was another a key feature of UCAN.

A Decade of Follow-Up to Assess the Risk of Recurrence and Surgery after a First Episode of Uncomplicated Left-Sided Diverticulitis

Background and aims: Acute uncomplicated diverticulitis (UD) of the left colon is common and mostly benign. Due to controversy over the definition of UD and the lack of adequate follow-up in most studies, good quality data to predict long-term outcomes after a first episode of UD are missing. The aim of this study was to assess the long-term risk for adverse outcomes after a first episode of UD. Methods: All consecutive patients with a CT-scan-documented first episode of acute UD (staged “uncomplicated” according to ESCP guidelines and/or modified Hinchey stages 0-1a, and/or CDD 1-2a) between January 2010 and June 2013 were included in the study. CT scans and clinical records were retrospectively reviewed. The primary endpoint was overall recurrence; the secondary endpoint was surgery for diverticular disease. Results: One hundred and five patients were included in the study with a median follow-up of 116.4 (4.9–154.7) months. Of these, 51 (48.5%) patients had a recurrence, 11 (10.4%) had 4 or more episodes. Twenty-one (20%) patients underwent sigmoidectomy, all in an elective setting, mostly due to multiple recurrent episodes. Male gender was the only independent risk factor for surgery (OR (95%CI): 0.301 (0.109–0.834), p = 0.021). Classification systems did not predict recurrence, but stage CDD 1a was protective for surgery (OR (95%CI): 0.201 (0.042–0.957), p = 0.044). Conclusions: After a decade of follow-up, almost half the patients experienced at least one recurrent episode after UD, higher than previously thought. None of those patients required emergency surgery, but one in five patients, mostly men, underwent elective sigmoidectomy for multiple recurrent episodes.

Changes in the ratio of neutrophils to albumin depending on the severity of abdominal sepsis in patients with benign and malignant non-traumatic perforation of the left colon

Background. According to the Third International Consensus (Sepsis-3), sepsis is defined as a life-threatening organ dysfunction caused by an uncontrolled response of the affected organism to a new infection, and septic shock as a sepsis-related condition characterized by the development of circulatory failure accompanied by arterial hypotension, with lactatemia and requiring maintenance of blood pressure with vasopressors. Despite progress in diagnosing and treating sepsis in patients with intra-abdominal infections, it continues to be the leading cause of mortality among patients in emergency departments worldwide. Purpose – the objective of this study was to ascertain the capacity of the neutrophilto-albumin ratio (NAR) before surgery to predict the severity of abdominal sepsis and 30-day mortality in patients with benign and malignant non-traumatic perforation left side of the colon. Methods. This was a retrospective, cross-sectional study that analyzed 117 patients of different age groups with sepsis caused by colon perforation who were hospitalized and operated on from January 2014 to March 2024. To evaluate the diagnostic value of INA in predicting sepsis severity and 30-day mortality, we analyzed the biomarker’s ROC curves, including the determination of optimal cut-off thresholds and associated specificity and sensitivity. The association of INA, sepsis severity, and perforation type with 30-day mortality was investigated using survival analysis, including the comparison of Kaplan–Meier curves and the development and analysis of Cox proportional hazards regression models. Comparisons between groups of study patients concerning quantitative characteristics were conducted, with the presence of septic shock and treatment outcome serving as the independent variables. This was done using nonparametric criteria for independent measurements, specifically the Kruskal–Wallis and Mann–Whitney tests. The statistical significance of the relationships between the qualitative indicators of the study was assessed based on the χ2 criterion and the odds ratio. Results. The results demonstrated that the INR has a high prognostic value in determining the severity of sepsis. This was evidenced by a high value of the area under the ROC curve (AUC = 0.948, p = 2, 309×10–41 &lt; 0.05, 95% CI = 0.882–1.013). It has been demonstrated that the development of septic shock can be predicted by a preoperative INA value not exceeding 22.1, with the highest possible specificity (93.4%) and sensitivity (92.3%). The INA was also found to be an effective predictor of 30-day mortality in our data. The optimal INA threshold for mortality prediction was 23.8, with a specificity of 77.1 and sensitivity of 78.7% (AUC = 0.862, p = 6,072 ×10–28 &lt; 0.05, 95% CI = 0.786-0.919). Furthermore, no statistically significant association was observed between the type of perforation and patient outcomes (χ2 = 0.00493, p = 0.944, p &gt; 0.05). However, our study did confirm higher 30-day mortality in patients with colonic perforation in the presence of septic shock compared to patients with sepsis. Conclusions. The neutrophil-to-albumin ratio has been identified as an accurate and reliable biomarker for predicting the severity of abdominal sepsis. The biomarker demonstrated a specificity of 93.4%, a sensitivity of 92.3%, and a cut-off value of 22.1 for stratifying patients with septic shock. Furthermore, this biomarker was identified as an important predictor of 30-day mortality in both types of perforation, with an area under the ROC curve (AUC) of 0.862. Nevertheless, the value of this indicator for predicting mortality was somewhat lower than for determining septic shock. Furthermore, the results of the Cox regression analysis indicated that the impact of IA on survival was more pronounced in patients with malignant colon perforation. In patients with benign colon perforation, the model demonstrated a satisfactory fit to the input data. The presence or absence of septic shock did not influence the survival of patients in this category. The findings of the study indicated a significant correlation between INA and sepsis severity, suggesting that this indicator may serve as a straightforward prognostic tool for determining the severity of sepsis before surgery. Ultimately, the stratification of patients according to the severity of sepsis before surgery may lead to improved clinical outcomes for these patients.

Sidedness and Molecular Pattern in Defining the Risk of Lymph Node Metastasis in Nonmetastatic Colorectal Cancer: Single-Center Retrospective Study.

Background: Lymphadenectomy plays a central role in the treatment of localized colon cancer. While in left colon cancer the D3 lymphadenectomy/CME is considered the standard of care, lymphatic stations to be removed in right colon cancer are still a matter of discussion. The individuation of LNM risk factors could help in choosing the lymphadenectomy in right-sided tumors. This study aims to analyze the correlation of histopathological and molecular characteristics with lymph node metastasis, both in right- and left-sided colon cancer, and their impact on survival; Methods: We conducted a single-center observational retrospective study. The following data were collected and analyzed for each patient: demographics, histopathological and molecular data, and intraoperative and perioperative data. Statistical analyses were performed, including descriptive statistics, multivariate logistic regression and survival analysis; Results: An association between tumor size (pT, p < 0.001), grading (p = 0.013), budding (p < 0.001), LVI (79,4% p < 0.001) and LNM was observed. A multivariate analysis identified pT4 (OR 5.45, p < 0.001) and LVI+ (OR 10.7, p < 0.001) as significant predictors of LNM. Right-sided patients presented a worse OS when associated with LNM, while no significant difference was observed in N0 patients; Conclusions: histological and molecular analysis can help identify high risk patients, which could benefit from extended lymphadenectomies. These patients could be ideal candidates for the D3 lymphadenectomy/CME.

Efficacy of colonoscopic re-examination across the entire colon: a randomized controlled trial.

In standard colonoscopic examinations, some polyps may be missed during the withdrawal phase. Re-examination of the right colon can improve the adenoma detection rate (ADR). However, the effectiveness of applying this re-examination strategy to the entire colon remains unknown. We investigated whether re-examination could increase the detection rate of polyps and adenomas throughout the colon. A randomized, controlled, single-center trial (NCT03268200) was conducted in a university hospital. Patients aged 45-75years were randomly assigned to either the study or control group. For patients in the control group, observation and polypectomy were performed once using the standard colonoscopy method. For patients in the study group, polypectomy was repeated twice during the withdrawal phase after the initial insertion of the colonoscope. These examinations were performed in the right transverse and left colons. The primary endpoints were the polyp detection rate (PDR) and ADR, defined as the proportion of patients with ≥ 1 polyp and ≥ 1 adenoma, respectively. Overall, 406 patients were enrolled (study group, n = 210; control group, n = 196) and analyzed. Generally, PDRs and ADRs were similar between the study (withdrawal 1 + 2) and control groups (withdrawal 1), except for the right colon. However, the second withdrawal review increased number of polyps and adenomas in the overall, right, mid, and left colon, respectively. The results of this trial indicated that re-examination of the entire colon during colonoscopy could be beneficial for detecting concealed polyps in patients at risk of interval cancer.

Abstract A048: Association between ambient particulate matter and colorectal cancer incidence: The Multiethnic Cohort Study

Abstract Background: Growing evidence suggests that air pollution may be a risk factor for colorectal cancer (CRC). We examined the association between ambient particulate matter (PM) exposure and CRC risk within the Multiethnic Cohort Study (MEC), representing the first study to include a large sample of racial and ethnic minoritized populations. Methods: The MEC is a prospective study that recruited, from 1993 through 1996, men and women ages 45-75 years largely from five racial and ethnic groups (African American, Japanese American, Latino, Native Hawaiian, and Non-Hispanic White) living in Hawai‘i and California. This study included 98,675 California MEC participants, residing predominately in Los Angeles County. Satellite-based PM2.5 (PM with an aerodynamic diameter &amp;lt;2.5μm) exposures were estimated from a published spatiotemporal model. Kriging interpolation was used to estimate PM10 (PM &amp;lt;10μm) exposures using routine air monitoring data from the US Environmental Protection Agency. Time-varying PM exposures were assessed from time of recruitment through 12/31/2018. Incident invasive CRC cases were identified via linkage with the California Cancer Registry (n=3,217). Cox proportional hazards models were used to examine the association between PM and CRC risk using age as the time metric, with strata defined by age at cohort entry and race and ethnicity, and adjusting for demographic and lifestyle factors. Heterogeneity of the PM-CRC association was assessed by sex, race and ethnicity, and CRC subsite (right colon, left colon, rectum). Results: Risk of CRC increased with PM2.5 (per 10μg/m3 hazard ratio [HR] 1.13, 95% confidence interval [CI] 0.96-1.33) with a larger HR observed among females (HR 1.29, 95% CI 1.03-1.62) than males (HR 0.96, 95% CI 0.76-1.22) (Pheterogeneity=0.24). CRC risk was positively associated with PM2.5 across race and ethnicity (except for African American participants) with the largest HR observed among Latino participants (HR 1.47, 95% CI 1.03-2.08) (Pheterogeneity=0.20). There was no statistically significant heterogeneity of PM2.5 effect by tumor subsite (Pheterogeneity=0.07); although larger HRs were seen for left colon (HR 1.52, 95% CI 1.08- 2.14) and rectal cancers (HR 1.54, 95% CI 1.05-2.25) than right colon cancers (HR 1.09, 95% CI 0.88-1.35). PM10 was not associated with CRC risk (per 10 μg/m3; HR 1.02, 95% CI 0.93-1.22) with no evidence of heterogeneity in associations by sex or race and ethnicity (respective Pheterogeneity 0.75, 0.44). Although HRs for PM10 appeared to differ by CRC subsite (Pheterogeneity=0.03), the 95% CI of these HRs included the null (right HR 0.95, 95% CI 0.84-1.06; left HR 1.13, 95% CI 0.95-1.35; rectal HR 1.18, 95% CI 0.97-1.43). Conclusions: Preliminary findings suggest that PM2.5 exposure is associated with CRC risk with larger associations in females and, possibly, for left colon and rectal cancer. Additional studies are needed to confirm these findings and evaluate the potential biological pathways underlying these associations. Citation Format: Ugonna Ihenacho, Chiuchen Tseng, Jun Wu, Scott Fruin, Timothy V. Larson, Salma Shariff-Marco, Loïc Le Marchand, Daniel O. Stram, Lynne R. Wilkens, Christopher A. Haiman, Beate Ritz, Iona Cheng, Anna H. Wu. Association between ambient particulate matter and colorectal cancer incidence: The Multiethnic Cohort Study [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr A048.

Organizational features of detection of secondary metachronic primary multiple colorectal cancer in a group of patients with extracolorectal malignancies

Aim – to study the organizational features of detection of secondary metachronous primary multiple CRC in patients with primary extracolorectal malignancies. Material and methods. The medical documentation of 163 oncological patients with extracolorectal malignancies and secondary metachronous CRC was analyzed. The patients were divided into subgroups according to the profile of dispensary observation. Results. In 66% (108) of cases, patients were diagnosed with malignancies of four subgroups: skin, breast, urological and gynecological spheres, the number of cases of malignancies’ localization correlated with the number of accumulated contingent. CRC at stage 1 was detected in 24% of cases. The right parts of the colon were affected in 22.1% (36) of cases, the left – in 38.7% (63), the rectum – in 33.1% (54), tumors of several departments – in 4.9% (8), anal cancer – in 1.2% (2) of cases. CRC was detected in the period from 7 to 678 months after extracolorectal malignancies. Earlier, CRC was diagnosed in cases with skin and urological tumors, later, in the group with breast cancer and oncogynecological profile. Conclusion. The majority of the subjects were women (60.7%), the average age was 69 years. Patients with oncodermatological (22%), oncourological (15.3%), oncomammological (15.3%), oncogynecological (13.5%) profiles, lesions of the left colon (38.7%) and rectum (33.1%) predominated. The time interval between the detection of the primary tumor and the detection of secondary CRC depends on the localization of the primary malignancies (p=0).Screening of CRC is necessary not only among the healthy population, but also in the group of patients with extracolorectal malignancies, it is possible to use an immunochemical quantitative stool test for hidden blood at the stage of providing specialized medical care in the "oncology" profile.

FP4.1 - Impact of adjuvant chemotherapy on the 5 Year Overall Survival for non-metastatic colon cancer patients in Bulgaria - a population wide based observational study

Abstract Aim Colon cancer patients who receive adjuvant chemotherapy later in life have lower survival rates. NCCN guidelines recommend the use of adjuvant chemotherapy for patients with non-metastatic colon cancer. Our study's objective was to examine how adjuvant chemotherapy affected the 5-year overall survival (OS) of patients diagnosed with non-metastatic colon cancer in Bulgaria. Methodology This is a retrospective population-wide observational analysis of 8968 cases that was reported as colorectal cancer (CRC) in the Bulgarian National Cancer Registry (BNCR) from 2015 to 2016. The mean and median ages of patients with right colon (RCC) and left colon (LCC) were examined. An analysis was conducted to determine the effect of adjuvant chemotherapy on the 5-year overall survival for non-metastatic colon cancer. To estimate the statistical significance, chi-squared tests, ANOVA, and the Kaplan-Meier curve with log rank were employed. Results In comparison to LCC, RCC had a higher mean age at diagnosis of 68.9 versus 67.41 (p-Value=&amp;lt;0.001). For RCC and LCC, the corresponding median ages at diagnosis were 69 and 68. The 5-year OS for patients with non-metastatic colon cancer who received adjuvant chemotherapy was higher than for patients who did not (67.8% vs. 59%, respectively, p-Value=0.007), according to our study. Adjuvant chemotherapy was given to slightly more than 30% of patients. Conclusion The 5-Year OS for patients with non-metastatic colon cancer is improved by adjuvant chemotherapy, and Bulgaria should follow NCCN guidelines. The implementation of a systematic screening program can be advantageous for Bulgaria as well.

Current sessile serrated lesion incidence: implications for future clinical practice.

Sessile serrated lesions (SSL) account for up to 30% of colorectal carcinoma pathogenesis. With multiple classification changes and improvements in colonoscopy equipment and technique, historical reporting may have underestimated the true incidence of SSLs. This study aimed to determine the incidence of SSLs in patients undergoing colonoscopic investigation in Canterbury, New Zealand over a 1-year period and describe their clinical and pathological characteristics. Electronic records were searched to identify all lower endoscopy procedures with polypectomy performed from 1 January 2022 to 1 December 2022 (inclusive). Patients' electronic records were used to collect histological classification, location and size of each polyp removed during their procedure. The primary outcome was the number of procedures that had one or more SSL, adenoma or hyperplastic polyp identified. Secondary outcomes included histological classification, location and size of each polyp removed. There were 4346 procedures completed during the study period. Of these, 64.1% (2786) had a polypectomy and 18.6% (808) had at least one SSL excised. Individual polyp analysis was completed on 9166 polyps and found that 24.0% of polyps removed were SSLs and they were found predominately in the right colon (65.1% right colon, 32.6% left colon, 2.3% rectum). SSLs were typically <10 mm (84.8%). This study found a higher incidence of SSLs compared to previous research. These results raise questions regarding whether SLL rates have been historically underestimated, whether SSL detection rate should be included as a key performance indicator and raises further concerns regarding the use of computed tomography colonography as a screening tool.

333. TECHNICAL CONSIDERATIONS IN UPPER-GI RECONSTRUCTION – A CASE SERIES

Abstract Background Oesophageal reconstruction post-oesophagectomy is performed for both benign and malignant pathologies. Generally, the stomach is the conduit of choice due to its simplicity, requiring only one anastomosis. However, in some cases the stomach may not be a viable option immediately or at all, and alternatives must be considered. We describe a case where the stomach was not immediately viable and two cases where alternative conduits were sought. Furthermore, we discuss techniques such as ‘supercharging’ and ‘superdrainage’ which enhance arterial flow and venous drainage respectively, in order to prevent ischaemia and related complications of the anastomosis site. Methods and Results Case 1 presents a 72-year-old with an incarcerated para-oesophageal hernia leading to necrosis of the distal oesophagus and proximal stomach. After resection, a feeding jejunostomy and a loop oesophagostomy in the neck was created. Months later, the oesophagostomy was closed, and the residual stomach was carefully mobilised into the thorax while preserving the gastro-epiploic arcade, and oesophago-gastric anastomosis was performed. Case 2 involves a 68-year-old female who had elective Nissen fundoplication for a hiatus hernia, which recurred early with strangulation of the distal oesophagus and proximal stomach requiring emergency oesophago-gastrectomy. She later underwent a colonic interposition using the left colon, with superdrainage through an anastomosis between a branch of the middle colic vein to the left external jugular vein. Case 3 describes a 61-year-old male with a gastro-oesophageal adenocarcinoma treated with an Ivor-Lewis oesophagectomy. A year later, he suffered from a strangulated diaphragmatic hernia causing necrosis of the gastric conduit. This was replaced with an isoperistaltic colonic interposition using the transverse and left colon with super drainage. Unfortunately, three years later, this was again complicated with pancreatitis and perforated gall bladder with associated ischaemia of the colonic conduit. A re-do of the colonic interposition using the right colon was done with an arterial graft between the right transverse cervical artery and branch of ileal artery and super drainage via a branch of the ileal and right external jugular veins. Conclusion Primary and in particular secondary re-constructions of the UGI tract are complex procedures and individual approaches are needed as residual anatomy varies. Consequently, such cases require meticulous planning and a multidisciplinary approach involving the cardio-thoracic, plastic and vascular surgeons and adequate support by the anaesthetic and intensive care team. Although associated with significant morbidity and mortality, reestablishment of a swallowing passage is often desired by patients to maintain quality of life.

Quantification of eosinophils in the lower gastrointestinal tract of adults: a review of surgical specimens with normal histology from the Free State province, South Africa.

Eosinophils are normal residents of the gastrointestinal tract (GIT). They are noted in small numbers with significant variation between anatomic locations. An idiopathic increase of eosinophils is known as eosinophilic gastrointestinal disease (EGID). EGIDs are a heterologous group of disorders that produce a range of enteric and colonic syndromes. Their incidence has been increasing worldwide. Our study aimed to quantify eosinophils in each segment of the GIT in surgical specimens with normal histology to facilitate the histological diagnosis of EGID. Similarly, we aimed to describe the effect of race and gender on gastrointestinal eosinophil numbers. A retrospective, quantitative comparative study was performed. We assessed 360 surgical specimens with normal histology from the lower gastrointestinal tract of African and Caucasian adults from the Free State Province, South Africa. The number of eosinophils per mm² was counted. Overall, comparable eosinophil values were noted for both males and females, and African and Caucasian South Africans. However, Caucasians recorded a higher concentration of eosinophils in the appendix and the left colon. Eosinophils were most numerous in the lamina propria, with only small numbers present in the epithelium. Our results show that the South African population has similar eosinophil distribution trends to international studies. However, South Africans had far fewer eosinophils than Japanese and North American adults in each segment. Specific eosinophil reference ranges were formulated to quantify reference ranges of eosinophils in the lower GIT, allowing for the accurate diagnosis of EGIDs in our population in future.

Objective performance indicators differ in obese and nonobese patients during robotic proctectomy

BackgroundRobotic surgery is perceived to be more complex in obese patients. Objective performance indicators, machine learning–enabled metrics, can provide objective data regarding surgeon movements and robotic arm kinematics. In this feasibility study, we identified differences in objective performance indicators during robotic proctectomy in obese and nonobese patients. MethodsEndoscopic videos were annotated to delineate individual surgical steps across 39 robotic proctectomies (1880 total steps). Thirteen patients were obese and 26 were nonobese. Objective performance indicators during the following steps were analyzed: splenic flexure mobilization, left colon mobilization, pelvic dissection, and rectal transection. ResultsThe following differences were noted during robotic proctectomy in obese patients: during splenic flexure mobilization, more arm swaps, longer camera path length and velocity; during left colon mobilization, longer step time, more arm swaps, higher camera-related metrics (movement, path length, velocity, acceleration, and jerk), greater dominant arm path length, moving time, and wrist articulation; during anterior pelvic dissection, longer energy activation time, camera path length, and moving time; during posterior pelvic dissection, lower nondominant arm velocity, jerk, and acceleration; during left pelvic dissection, longer energy activation time; during right pelvic dissection, greater camera-related metrics (movement, path length, moving time, and velocity); and during rectal transection, longer step time, more arm swaps, master clutch use and camera movements, greater dominant wrist articulation, and longer dominant arm path length. ConclusionWe report step-specific objective performance indicators that differ during robotic proctectomy for obese and nonobese patients. This is the first study to use objective performance indicators to correlate a patient attribute with surgeon movements and robotic arm kinematics during robotic colorectal surgery.

Single-cell RNA sequencing reveals the heterogeneity of MYH11+ tumour-associated fibroblasts between left-sided and right-sided colorectal cancer.

Colorectal cancer (CRC) exhibits considerable heterogeneity on tumour location. However, there is still a lack of comprehensive annotation regarding the characteristics and differences between the left-sided (L-CRC) and right-sided (R-CRC) CRC. Here, we performed single-cell RNA sequencing (scRNA-seq) on immune and stromal cells from 12 L-CRC and 10 R-CRC patients. We found that L-CRC exhibited stronger tumour invasion and poor prognosis compared with R-CRC. In addition, functional enrichment analysis of a normal cohort showed that fibroblasts of left colon are associated with tumour-related pathways. This suggested that the heterogeneity observed in both L-CRC and R-CRC may be influenced by the specific location within the colon itself. Further, we identified a potentially novel MYH11+ cancer-associated fibroblast (CAF) subset predominantly enriched in L-CRC. Moreover, we found that MYH11+ CAFs may promote tumour migration via interacting with macrophages, and was associated with poor prognosis in CRC. In summary, our study revealed the crucial role of MYH11+ CAFs in predicting a poor prognosis, thereby contributing valuable insights to the exploration of heterogeneity in L-CRC and R-CRC.

Prognostic and Predictive Significance of Primary Tumor Localization and HER2 Expression in the Treatment of Patients with KRAS Wild-Type Metastatic Colorectal Cancer: Single-Centre Experience from Serbia.

The treatment of patients with metastatic colorectal cancer (mCRC) is complex and is impacted by the location of the primary tumor (LPT). Our study aims to emphasize the importance of LPT as a prognostic and predictive marker as well as to examine the significance of HER2 overexpression in patients with mCRC, particularly in relation to the response to Epidermal Growth Factor Receptor Antibody treatment (anti-EGFR therapy). In this study, 181 patients with Kirsten RAS (KRAS) wild-type mCRC who received anti-EGFR therapy were included. Among them, 101 had left colon cancer (LCC) and 80 had right colon cancer (RCC). Results demonstrated that patients with KRAS wild-type LCC had better median overall survival (OS) (43 vs. 33 months, p = 0.005) and progression-free survival (PFS) (6 vs. 3 months, p < 0.001) compared to those with RCC. Multivariate analysis identified mucinous adenocarcinoma (p < 0.001), RCC location (p = 0.022), perineural invasion (p = 0.034), and tumors at the resection margin (p = 0.001) as independent predictors of OS, while mucinous adenocarcinoma (p = 0.001) and RCC location (p = 0.004) independently correlated with significantly shorter PFS. In addition, human epidermal growth factor receptor 2 (HER2) positive expression was significantly associated with worse PFS compared to HER2 negative results (p < 0.001). In conclusion, LPT is an important marker for predicting outcomes in the treatment of wild-type mCRC using anti-EGFR therapy, since patients with RCC have a statistically significantly shorter PFS and OS. Further investigation is needed to understand the role of HER2 overexpression in wild-type mCRC, as these patients also exhibit shorter survival.

The correlation between L1CAM expression and outcomes in patients with metastatic colorectal cancer treated with first-line chemotherapy.

95 Background: L1CAM is a cell adhesion molecule and stem cell marker belonging to the immunoglobulin superfamily of cell adhesion molecules (IgCAMs). L1CAM may be aberrantly expressed in several types of human tumors. The aim of the present study was to evaluate the correlation between L1CAM expression and outcomes in patients with metastatic colorectal cancer. Methods: We retrospectively collected data from 51 mCRC pts treated between 2017 and 2022 at the Medical Oncology Unit of the University Hospital of Cagliari. Tumor samples were retrospectively tested for L1CAM immunohistochemical (IHC) expression with the aim of evaluating the correlation with clinical outcome in terms of overall survival (OS) and progression-free survival (PFS). The primary endpoint was the mOS while secondary endpoint was mPFS. The aim of the present analysis was to evaluate the role of L1CAM expression in tumor cells in predicting the clinical outcome of CRC patients treated with standard chemotherapy. Statistical analysis was performed with the MedCalc Statistical Sofware Version 14.10.2. Results: Median age was 70 (±13), 58.8% were males and 41.2% were females. 29.4% of pts had carcinoma of the right colon, 39.2% left colon and 31.4% rectum. Negative or weak L1CAM score 0 was observed in 39.2% patients; 43.1% pts showed a score 1+; 11.8% showed score 2+, and 5.9% showed score 3+. Positivity for L1CAM correlated with a worse prognosis. The median OS for pts not expressing L1CAM was 74.0 months versus 32.0 for patients expressing the biomarker ( p = 0.0021). The mPFS for patients not expressing L1CAM was 21.0 months, vs 6.0 for patients expressing the biomarker ( p = 0.0066). The same negative correlation on outcomes was shown based on the degree of L1CAM expression. A different L1CAM score corresponded to a different OS and PFS. Pts with score 0 showed a mOS of 74 months vs 37 and 18 months for scores 1+ and 2+/3+, respectively ( p &lt; 0.0001). Similar results were obtained with the mPFS: patients with score 0 showed a median of 21 months vs 8 and 2 months for scores 1+ and 2+/3+, respectively ( p = 0.0138). Conclusions: L1CAM expression in cancer cells correlates with a worse prognosis in mCRC patients. Immunohistochemical evaluation of this biomarker could allow the identification of a subgroup of patients capable of benefiting from a targeted therapy.

Prognostic impact of codon-specific KRAS mutational status on survival in patients with metastatic colorectal cancer treated with TAS-102 or regorafenib.

75 Background: Previous study demonstrated KRAS (Kirsten rat sarcoma virus) codon G12 mutation as a potential biomarker of resistance in metastatic colorectal cancer (mCRC). Our study aimed to evaluate the prognostic impact of codon-specific KRAS mutational status on survival in patients with mCRC treated with TAS-102 or regorafenib. Methods: mCRC Patients treated with TAS-102 or regorafenib were retrospectively enrolled into our study. Patients were classified into KRAS G12 (KRASG12) mutation and no KRASG12 mutation according to extended RAS testing. Survival was estimated for comparison, stratified by KRAS mutational status and treatment. Kaplan-Meier curves were estimated for overall survival (OS). Results: A total of 183 patients were enrolled into our study, with 91 patients treated with TAS-102 and 92 patients treated with regorafenib. The median age was 63 years old in our cohort. Most patients were male (54%) with left side colon (85%). After extended RAS/RAF mutational testing, 28% patients had KRASG12 mutation, 50% had RAS/RAFWT, 9% had KRASG13 mutation, 8% had KRASother mutation, 3% had NRAS mutation and 2% had BRAF mutation. For patients treated with TAS-102 group, 20% patients had KRASG12 mutation, while for regorafenib group, 38% patients had KRASG12 mutation. The median OS of TAS-102 was 4.5 versus 11.3 months for KRASG12 mutation and no KRASG12 mutation, respectively (p= 0.013). The median OS of regorafenib was 10.5 versus 6.3 months for KRASG12 mutation and no KRASG12 mutation, respectively (p= 0.183). Furthermore, 34% patients with KRASG12 mutation received TAS-102, while 56% patients without KRASG12 mutation received TAS-102. For patients with KRASG12 mutation, the median OS was 4.5 m versus 10.5 months for TAS-102 and regorafenib group, respectively (p= 0.113). For patients without KRASG12 mutation, the median OS was 11.3m versus 6.3 months for TAS-102 and regorafenib group, respectively (p= 0.047). Conclusions: The prognostic impact of KRASG12 was divergent between mCRC patients treated with TAS-102 and regorafenib. Codon-specific KRAS mutational status should be taken into consideration before treatment.