Hepatitis C Virus Reinfection Among Men Who Have Sex With Men With HIV in New York City.

BACKGROUND: Hepatitis C virus (HCV) reinfection rates are substantially higher than primary infection rates among men who have sex with men (MSM) with human immunodeficiency virus (HIV) in European cohorts. The behaviors mediating this high rate of transmission among MSM are poorly characterized. METHODS: We performed a prospective cohort study in New York City (NYC) of MSM with HIV who cleared HCV to determine the incidence of and risk factors for HCV reinfection. We assessed the risk behaviors for primary HCV in NYC: receipt of semen in the rectum, and sexualized methamphetamine use, along with route of use. Multivariable analysis was performed with Andersen-Gill extension of the Cox proportional hazards model. RESULTS: From 2000 through 2018, among 304 MSM with HIV who cleared HCV, 42 reinfections occurred over 898 person-years, for an incidence rate of 4.7 per 100 person-years. Assessing 1245 postclearance visits, only receipt of semen into the rectum was associated with reinfection (hazard ratio, 9.7 [95% confidence interval: 3.3-28.3], P < .001); methamphetamine use was not. CONCLUSIONS: The high HCV reinfection rate over almost 2 decades demonstrates that sexual transmission of HCV is not inefficient or unusual and that direct-acting antiviral treatment is not sufficient for HCV elimination among MSM in NYC. The contrasts between both the rates of and risk factors for primary and HCV reinfection suggest that HCV prevalence is highly heterogenous among sexual networks and that sexualized methamphetamine use, rather than mediating transmission, is instead a surrogate marker for the highest HCV prevalence networks. As neither condoms nor treatment have been successful strategies for HCV prevention in NYC, novel interventions are needed to stem this sexually transmitted HCV epidemic.

Changes in microbial composition and interaction patterns of female urogenital tract and rectum in response to HPV infection.

BACKGROUND: Previous studies have shown that changes in the microbial community of the female urogenital tract are associated with Human papillomavirus (HPV) infection. However, research on this association was mostly focused on a single site, and there are currently few joint studies on HPV infection and multiple sites in the female urogenital tract. METHODS: We selected 102 healthy women from Yunnan Province as the research object, collected cervical exfoliation fluid, vaginal, urethral, and rectal swabs for microbial community analysis, and measured bacterial load, and related cytokine content. The link between HPV, microbiota, and inflammation was comprehensively evaluated using bioinformatics methods. FINDINGS: The impact of HPV infection on the microbial composition of different parts varies. We have identified several signature bacterial genera that respond to HPV infection in several detection sites, such as Corynebacterium, Lactobacillus, Campylobacter, and Cutibacterium have been detected in multiple sites, reflecting their potential significance in cross body sites HPV infection responses. There was a solid microbial interaction network between the cervix, vagina, and urethra. The interrelationships between inflammatory factors and different bacterial genera might also affect the immune system's response to HPV infection. INTERPRETATION: It might be an effective strategy to prevent and treat HPV infection by simultaneously understanding the correlation between the microbial changes in multiple parts of the female urogenital tract and rectum and HPV infection, and controlling the microbial network related to HPV infection in different parts.

Risk Factor Analysis of Lymph Node Metastasis for Rectal Neuroendocrine Tumors: Who Needs a Radical Resection in Rectal Neuroendocrine Tumors Sized 1-2 cm?

BACKGROUND: Rectal neuroendocrine tumors (NETs) have malignant potential, and lymph node (LN) or distant metastases can occur; however, treatment of NETs 1-2 cm in size is controversial. OBJECTIVE: This study aimed to identify predictive factors for LN metastasis and prognostic factors for recurrence of rectal NETs, especially tumors 1‒2 cm in size. METHODS: Between October 2004 and November 2020, 453 patients underwent endoscopic or surgical treatment for rectal NETs in Seoul National University Hospital. The data on these patients were prospectively collected in our database and reviewed retrospectively. In cases of local excision, we evaluated LN metastasis with radiologic imaging, including computed tomography or magnetic resonance imaging before treatment and during the follow-up periods. RESULTS: LN metastasis was observed in 40 patients (8.8%). A higher rate of LN metastasis was observed in larger-sized tumors, advanced T stage, lymphovascular invasion (LVI), perineural invasion (PNI), and high tumor grade. In multivariable analysis, the significant risk factors for LN metastasis were tumor size (1 ≤ size < 2 cm: hazard ratio [HR] 64.07; size ≥2 cm: HR 102.37, p < 0.001) and tumor grade (G2: HR 3.63, p = 0.034; G3: HR 5.09, p = 0.044). In multivariable analysis for tumors 1-2 cm in size, the risk factor for LN metastasis was tumor grade (G2: HR 6.34, p = 0.013). CONCLUSIONS: Tumor grade and size are important predictive factors for LN metastasis. In NETs 2 cm in size, tumor grade is also important for LN metastasis, and radical resection should be considered.

The Association of Mismatch Repair Status with Microscopically Positive (R1) Margins in Stage III Colorectal Cancer: A Retrospective Cohort Study.

BACKGROUND: There is mounting evidence that microscopically positive (R1) margins in patients with colorectal cancer (CRC) may represent a surrogate for aggressive cancer biology rather than technical failure during surgery. However, whether detectable biological differences exist between CRC with R0 and R1 margins is unknown. We sought to investigate whether mismatch repair (MMR) status differs between Stage III CRC with R0 or R1 margins. METHODS: Patients treated for Stage III CRC from January 1, 2016 to December 31, 2019 were identified by using the Danish Colorectal Cancer Group database. Patients were stratified according to MMR status (proficient [pMMR] vs. deficient [dMMR]) and margin status. Outcomes of interest included the R1 rate according to MMR and overall survival. RESULTS: A total of 3636 patients were included, of whom 473 (13.0%) had dMMR colorectal cancers. Patients with dMMR cancers were more likely to be elderly, female, and have right-sided cancers. R1 margins were significantly more common in patients with dMMR cancers (20.5% vs. 15.2%, p < 0.001), with the greatest difference seen in the rate of R1 margins related to the primary tumour (8.9% vs. 4.7%) rather than to lymph node metastases (11.6% vs. 10.5%). This association was seen in both right- and left-sided cancers. On multivariable analyses, R1 margins, but not MMR status, were associated with poorer survival, alongside age, pN stage, perineural invasion, and extramural venous invasion. CONCLUSIONS: In patients with Stage III CRC, dMMR status is associated with increased risks of R1 margins following potentially curative surgery, supporting the use of neoadjuvant immunotherapy in this patient group.

Laparoscopic versus open surgery for rectal neuroendocrine tumors: a multicenter real-world study.

BACKGROUND: Owing to the lack of evidence-based medical studies with large sample sizes, the surgical approach for the radical resection of rectal neuroendocrine tumors remains controversial. METHODS: We retrospectively collected the medical records of patients with rectal neuroendocrine tumors who underwent radical resection at 17 large tertiary care hospitals in China between January 1, 2010, and April 30, 2022. All patients were divided into laparoscopic and open surgery groups. After propensity score matching to reduce confounders, the postoperative and oncologic outcomes were compared between the groups. RESULTS: We enrolled 174 patients with rectal neuroendocrine tumors who underwent radical surgery. After random matching, 124 patients were included in the comparison (62, laparoscopic surgery group; 62, open surgery group). The laparoscopic surgery group had fewer complications (14.5% vs. 35.5%, P = 0.007) and superior relapse-free survival (P = 0.048). Subgroup analysis revealed that the laparoscopic surgery group had fewer complications (10.9% vs. 34.7%, P = 0.004), shorter postoperative hospital stays (9.56 ± 5.21 days vs. 12.31 ± 8.61 days, P = 0.049) and superior relapse-free survival (P = 0.025) in the rectal neuroendocrine tumors ≤ 4 cm subgroup. CONCLUSIONS: Laparoscopic surgery was associated with improved postoperative outcomes and oncologic prognosis for patients with rectal neuroendocrine tumors ≤ 4 cm; it can serve as a safe and feasible option for radical surgery of rectal neuroendocrine tumors.

Anatomy of muscle connections in the male urethra and anorectal canal.

OBJECTIVES: To elucidate the male urethral muscular structure and its relationship with the anorectal canal muscles, as establishing an anatomical foundation for urethral function will contribute to the prevention, diagnosis, and treatment of urinary incontinence. METHODS: Eight male cadavers were used. Using a multifaceted approach, we performed macroscopic anatomical examination, histological analysis of wide-range serial sectioning and immunostaining, and three-dimensional (3D) reconstruction from histological sections. In the macroscopic anatomical examination, pelvic halves were meticulously dissected in layers from the medial aspect. In the histological analysis, the tissue, including the urethra and anorectal canal, was serially sectioned in the horizontal plane. The muscular structures were reconstructed and visualised in 3D. RESULTS: The membranous portion of the urethra had three muscle layers: the longitudinal and circular muscles (smooth muscle) and the external urethral sphincter (skeletal muscle). The circular muscle was connected posteriorly to the longitudinal rectal muscle. The external urethral sphincter had a horseshoe shape, with its posterior ends continuing to the external anal sphincter, forming a 3D ring-like sphincter. CONCLUSION: This study revealed skeletal and smooth muscle connections between the male urethra and anorectal canal, enabling urethral compression and closure. These anatomical muscle connections suggest a functional linkage between them.

Evaluation of association between center colorectal neuroendocrine neoplasm volume and survival among patients with colorectal neuroendocrine carcinoma.

BACKGROUND: Although correlation between center volume and survival has been reported for several complex cancers, it remains unknown if this is true for colorectal neuroendocrine carcinomas (CRNECs). We hypothesized that higher center annual volume of colorectal neuroendocrine neoplasm resections would be associated with overall survival (OS) for patients with CRNECs. METHODS: Patients in the National Cancer Database diagnosed with stages I-III CRNEC between 2006 and 2018 and who underwent surgical resection were identified. The mean annual colorectal neuroendocrine neoplasm resection volume threshold associated with significantly worse mortality hazard was determined using restricted cubic splines. Kaplan-Meier (KM) method was used to compare OS, while Cox proportional hazards model was used for multivariable analysis. RESULTS: There were 694 patients with CRNEC who met inclusion criteria across 1229 centers. Based on the cubic spline, centers treating fewer than one colorectal neuroendocrine neoplasm patient every 3 years on average had worse outcomes. Centers below this threshold were classified as low-volume (LV) centers corresponding with 42% of centers and about 15% of the patient cohort. In unadjusted survival analysis, LV patients had a median OS of 14 months (95% confidence interval [CI]: 10-19) while those treated at HV centers had a median OS of 33 months (95% CI: 25-49). In multivariable analysis, resection at a LV center was associated with increased risk of mortality (1.42 [95% CI: 1.01-2.00], p = 0.04). CONCLUSION: CRNEC patients have a dire prognosis; however, treatment at an HV center may be associated with decreased risk of mortality.

Assessing risk stratification in long-term outcomes of rectal neuroendocrine tumors following endoscopic resection: a multicenter retrospective study.

OBJECTIVES: While endoscopic resection of rectal neuroendocrine tumors (NETs) has significantly increased, long-term data on risk factors for recurrence are still lacking. Our aim is to analyze the long-term outcomes of patients with rectal NETs after endoscopic resection through risk stratification. METHODS: In this multicenter retrospective study, we included patients who underwent endoscopic resection of rectal NETs from 2009 to 2018 and were followed for ≥12 months at five university hospitals. We classified the patients into three risk groups according to the clinicopathological status of the rectal neuroendocrine tumors: low, indeterminate, and high. The high-risk group was defined if the tumors have any of the followings: size ≥ 10 mm, lymphovascular invasion, muscularis propria or deeper invasion, positive resection margins, or mitotic count ≥2/10. RESULTS: A total of 346 patients were included, with 144 (41.6%), 121 (35.0%), and 81 (23.4%) classified into the low-, indeterminate-, and high-risk groups, respectively. Among the high-risk group, seven patients (8.6%) received salvage treatment 28 (27-67) days after the initial endoscopic resection, with no reported extracolonic recurrence. Throughout the follow-up period, 1.1% (4/346) of patients experienced extracolonic recurrences at 56.5 (54-73) months after the initial endoscopic resection. Three of these patients (75%) were in the high-risk group and did not undergo salvage treatment. The risk of extracolonic recurrence was significantly higher in the high-risk group compared to the other groups (p = 0.039). CONCLUSION: Physicians should be concerned about the possibility of metastasis during long-term follow-up of high-risk patients and consider salvage treatment.

Preoperative beta blockers and other drugs in relation to anastomotic leakage after anterior resection for rectal cancer.

AIM: Previous research has indicated that preoperative beta blocker therapy is associated with a decreased risk of complications after surgery for rectal cancer. This is thought to arise because of the anti-inflammatory activity of the drug. These results need to be reproduced and analyses extended to other drugs with such properties, as this information might be useful in clinical decision-making. The main aim of this work was to replicate previous findings of beta blocker use as a prognostic marker for postoperative leakage. We also investigated whether drug exposure might induce anastomotic leaks. METHOD: This is a retrospective multicentre cohort study, comprising 1126 patients who underwent anterior resection for rectal cancer between 2014 and 2018. The use of any preoperative beta blocker was treated as the primary exposure, while anastomotic leakage within 12 months of surgery was the outcome. Secondary exposures comprised angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, statins and metformin. Using multivariable regression, we performed a replication analysis with a predictive aim for beta blockers only, while adjustment for confounding was done in more causally oriented analyses for all drugs. We estimated incidence rate ratio (IRR) and relative risk (RR) with 95% confidence intervals (CIs). RESULTS: Anastomotic leakage occurred in 20.6% of patients. Preoperative beta blockers were used by 22.7% of the cohort, while the leak distribution was almost identical between exposure groups. In the main replication analysis, no association could be detected (IRR 0.95, 95% CI 0.68-1.33). In the causally oriented analyses, only metformin affected the risk of leakage (RR 1.59, 95% Cl 1.31-1.92). CONCLUSION: While previous research has suggested that preoperative beta blocker use could be prognostic of anastomotic leakage, this study could not detect any such association. On the contrary, our results indicate that preoperative beta blocker use neither predicts nor causes anastomotic leakage after anterior resection for rectal cancer.

Gastrointestinal Tract Granular Cell Tumor in the Pediatric Population: A Multicenter Experience.

BACKGROUND: Pediatric granular cell tumors (GCT) involving the gastrointestinal tract (GIT) are rare with limited case report/series reported to date. METHODS: Multicenter retrospective study of pediatric GIT GCT. RESULTS: A total of 10 cases were included in the study with a median age of 13.5 years (range: 7-18 years) and were predominantly female patients (60%). In half of the patients no significant medical history was present with the remaining 5 having Crohn disease (10%), eosinophilic esophagitis (EoE) (10%), Crohn disease and EoE (10%), growth hormone deficiency (10%), and aplasia cutis congenita (10%). The GCT median size was 1.3 cm (range: 1-1.6 cm) and were more commonly located in the esophagus (70%) followed by the stomach (20%) and rectum (10%). Most of the cases showed round/polygonal tumor cells with abundant granular cytoplasm, and none of the cases had nuclear atypia, increased mitotic activity, or tumor cell necrosis. None of our cases received specific therapy for GCT other than clinical follow-up, and none of the patients had evidence of local recurrence or metastatic disease. CONCLUSION: We present our multicenter experience with GIT GCT, all cases had a benign course. Interestingly, 4 of the esophageal GCT cases (including 2 patients with EoE) showed an eosinophil-rich esophagitis in the underlying mucosa.

The role of endoscopic ultrasonography for diagnosis of residual rectal neuroendocrine tumor.

BACKGROUND: Endoscopic ultrasonography (EUS) is useful for assessing the depth and regional lymph node involvement in rectal neuroendocrine tumors (NETs). However, evidence regarding the effectiveness of EUS in identifying residual lesions in patients with incompletely resected NET is limited. We aimed to evaluate the efficacy of EUS in identifying residual rectal NETs and the clinical outcomes of salvage endoscopic treatment. METHODS: We retrospectively reviewed the records of patients who were transferred to Chosun University Hospital and received salvage treatment for incompletely resected rectal NETs between January 2012 and October 2021. RESULTS: This study included 68 incompletely resected rectal NET, of which 59 were margin-positive and 9 were margin-indeterminate. EUS detection (odds ratio (OR), 8.44; 95% confidence interval (CI), 1.18-41.35) and visual detection (OR, 7.00; 95% CI, 1.50-47.48) were associated with residual lesion in patients with incompletely resected NET. EUS detection of residual lesions showed a sensitivity of 94%, specificity of 71%, positive predictive value of 88%, negative predictive value of 83%, and accuracy of 87%. All patients underwent salvage treatment with band-ligation endoscopic mucosal resection (58.8%) and endoscopic submucosal dissection (41.2%). Residual NETs were diagnosed in 47 of 68 patients (69.1%), and no recurrence was noted during the follow-up period of 51.8 ± 22.9 months. CONCLUSIONS: EUS is a more sensitive method than visual detection for evaluating residual rectal NETs. Salvage endoscopic treatment for incompletely resected NETs is safe and effective.

Gross morphologic features of surgical specimen in rectal cancer patients with pathological complete response following neoadjuvant chemoradiotherapy: A cross-sectional study.

BACKGROUND: pathological complete response (pCR) is achieved in 10%-30% of rectal cancer patients following neoadjuvant chemoradiotherapy and surgery. Residual mucosal abnormalities, which make patients ineligible for nonoperative management, may not be an accurate indicator of the pCR. The purpose of this study was to report the gross findings of rectal cancer patients with pathological complete responses. METHODS: This study was conducted at Tehran University of Medical Sciences, Tehran, Iran. A total of 130 patients with rectal adenocarcinoma, treated by neoadjuvant chemoradiotherapy, followed by surgical resection between March 2007, and March 2017, with a surgical pathology report of pCR, were included. Patients' demographics and pretreatment tumor characteristics were collected from the medical records. Data regarding residual mucosal abnormalities were extracted from postoperative surgical pathology reports. Abnormal findings were reported as "ulcer" or " non-ulcerative lesion". RESULTS: One hundred and fifteen patients (88.5%; 95% CI: 81.7%-93.4%) had at least one abnormal finding in the gross examination, including ulcer or non-ulcerative lesion (any mucosal abnormalities other than ulcers, including polyps, telangiectasia, etc.). Patients with higher-stage tumors had a higher chance of having an ulcerative lesion (p = 0.05). Younger patients tended to have deeper layers of involvement (p = 0.013). Patients with different gross findings were not significantly different regarding baseline characteristics, except for the pretreatment stage, where patients with a higher stage had higher odds of having ulcerative lesions. CONCLUSIONS: Most rectal cancer patients achieving a pCR exhibit abnormalities on gross examination. The higher pretreatment stages were significantly associated with gross abnormalities especially ulcers.

Influence of additional prophylactic oral antibiotics during mechanical bowel preparation on surgical site infection in patients receiving colorectal surgery.

BACKGROUND: Prophylactic antibiotics (PAs) are standard for preventing surgical site infections (SSIs) post-colorectal surgery. This study aims to compare the effect of additional empiric oral antibiotics (OAs) alongside routine PAs to identify SSI risk factors. METHODS: A retrospective observatory analysis was conducted from January 2019 to December 2022 at Asan Medical Center, Seoul, Korea. The cohort was divided into two groups: PA given 1 h before surgery and discontinued within 24 h, and OA administered empiric OAs during mechanical bowel preparation in addition to PA. RESULTS: From a total of 6736 patients, 3482 were in the PA group and 3254 in the OA group. SSI incidence showed no significant intergroup difference (p = 0.374) even after propensity score matching (p = 0.338). The multivariable analysis revealed male sex [odds ratio (OR): 2.153, 95% confidence interval (CI): 1.626-2.852, and p = 0.001], open surgery (OR: 3.335, 95% CI: 2.456-4.528, and p = 0.001), dirty wound (OR: 2.171, 95% CI: 1.256-3.754, and p = 0.006), and an operation time of more than 145 min (OR: 2.110, 95% CI: 1.324-3.365, and p = 0.002) as SSI risk factors. In rectal surgery subgroup, OA demonstrated a protective effect against SSI (OR: 0.613, 95% CI: 0.408-0.922, and p = 0.019) and in laparoscopic approach (OR: 0.626, 95% CI: 0.412-0.952, and p = 0.028). CONCLUSIONS: OA did not affect SSI incidence in colorectal surgeries. Male sex, open surgery, dirty wounds, and longer operation time were risk factors for SSI. However, for rectal and laparoscopic surgery, OA was a protective factor for SSI.

Prediction of postoperative residual primary ovarian neoplasm or metastatic lesion close to rectum of serous ovarian carcinoma based on clinical and MR T1-DEI features.

BACKGROUND: The optimal primary debulking surgery outcome of serous ovarian carcinoma (SOC) is greatly affected by primary ovarian neoplasm or metastatic lesion close to the rectum. PURPOSE: To study the risk factors affecting postoperative residual primary ovarian neoplasm or metastatic lesion close to the rectum of SOC. MATERIAL AND METHODS: The clinical and MRI data of 164 patients with SOC eligible from institution A (training and test groups) and 36 patients with SOC eligible from institution B (external validation group) were collected and retrospectively analyzed. The clinical data included age, serum carbohydrate antigen 125 (CA-125), human epididymis protein 4, and neutrophil-to-lymphocyte ratio (NLR). Magnetic resonance imaging (MRI) data included ovarian mass distribution, maximum diameter of ovarian mass, ovarian mass features, degree of rectal invasion of the primary ovarian neoplasm or metastatic lesion, and amount of ascites. A model was established using multivariate logistic regression. RESULTS: By univariate and multivariate logistic regressions, CA-125 (P = 0.024, odds ratio [OR] = 3.798, 95% confidence interval [CI] = 1.24-13.32), NLR (P = 0.037, OR = 3.543, 95% CI = 1.13-12.72), and degree of rectal invasion of the primary ovarian neoplasm or metastatic lesion (P < 0.001, OR = 37.723, 95% CI = 7.46-266.88) were screened as independent predictors. The area under the curve values of the model in the training, test, and external validation groups were 0.860, 0.764, and 0.778, respectively. CONCLUSION: The clinical-radiological model based on T1-weighted dual-echo MRI can be used non-invasively to predict postoperative residual ovarian neoplasm or metastasis close to SOC in the rectum.

Altered bile acid and correlations with gut microbiome in transition dairy cows with different glucose and lipid metabolism status.

The transition from pregnancy to lactation is critical in dairy cows. Among others, dairy cows experience a metabolic stress due to a large change in glucose and lipid metabolism. Recent studies revealed that bile acids (BA), besides being involved in both the emulsification and solubilization of fats during intestinal absorption, can also affect the metabolism of glucose and lipids, both directly or indirectly by affecting the gut microbiota. Thus, we used untargeted and targeted metabolomics and 16S rRNA sequencing approaches to investigate the concentration of plasma metabolites and BA, the composition of the rectum microbial community, and assess their interaction in transition dairy cows. In Experiment 1, we investigated BA and other blood parameters and gut microbiota in dairy cows without clinical diseases during the transition period, which can be seen as well adapted to the challenge of changed glucose and lipid metabolism. As expected, we detected an increased plasma concentration of ß-hydroxybutyrate (BHBA) and nonesterified fatty acids (NEFA) but decreased concentration of glucose, cholesterol, and triglycerides (TG). Untargeted metabolomic analysis of the plasma revealed primary BA biosynthesis was one of the affected pathways, and was consistent with the increased concentration of BA in the plasma. A correlation approach revealed a complex association between BA and microbiota with the host plasma concentration of glucose and lipid metabolites. Among BA, chenodeoxycholic acid derivates such as glycolithocholic acid, taurolithocholic acid, lithocholic acid, taurochenodeoxycholic acid, and taurodeoxycholic acid were the main hub nodes connecting microbe and blood metabolites (such as glucose, TG, and NEFA). In Experiment 2, we investigated early postpartum dairy cows with or without hyperketonemia (HPK). As expected, HPK cows had increased concentration of NEFA and decreased concentrations of glucose and triglycerides. The untargeted metabolomic analysis of the plasma revealed that primary BA biosynthesis was also one of the affected pathways. Even though the BA concentration was similar among the 2 groups, the profiles of taurine conjugated BA changed significantly. A correlation analysis also revealed an association between BA and microbiota with the concentration in plasma of glucose and lipid metabolites (such as BHBA). Among BA, cholic acid and its derivates such as taurocholic acid, tauro α-muricholic acid, and taurodeoxycholic acid were the main hub nodes connecting microbe and blood metabolites. Our results indicated an association between BA, intestinal microbe, and glucose and lipid metabolism in transition dairy cows. These findings provide new insight into the adaptation mechanisms of dairy cows during the transition period.

Palliative primary tumor resection may not offer survival benefits for patients with unresectable metastatic colorectal neuroendocrine neoplasms, one multicenter retrospective cohort study.

BACKGROUND: The efficacy of palliative primary tumor resection (PTR) in improving prognosis for patients with unresectable metastatic colorectal neuroendocrine neoplasms (NENs) has not been fully explored. METHODS: We performed one retrospective cohort study and recruited 68 patients with unresectable metastatic colorectal NENs from two Chinese medical centers between 2000 and 2022. All patients were assigned to PTR group and no PTR group. The clinicopathological manifestation data were carefully collected, and the survival outcomes were compared between the two groups using Kaplan-Meier methods. Propensity score matching (PSM) was conducted to minimize confounding bias. Univariate and multivariate Cox proportional hazards regression analyses were performed to identify prognostic factors. RESULTS: A total of 32 patients received PTR, and the other 36 patients did not. The median progression-free survival (PFS) and overall survival (OS) times were 4 and 22 months in the whole cohort, respectively. For patients who received no PTR, the median OS was 16 months, and the 1-year OS rate and 3-year OS rate were 56.4% and 39.6%, respectively. For patients who received PTR, the median OS was 24 months, and the 1-year OS rate and 3-year OS rate were 67.9% and 34.1%, respectively. However, the Kaplan-Meier survival curves and log-rank test demonstrated no significant survival difference between the two groups (P = 0.963). Moreover, palliative PTR was also not confirmed as a prognostic factor in subsequent univariable and multivariable Cox proportional hazards regression analyses in both the original and matched cohorts. Only histological differentiation was identified as an independent prognostic factor affecting PFS [hazard ratio (HR) = 1.86, 95% confidence interval (CI): 1.02-3.41, P = 0.043] and OS [HR = 3.70, 95% CI: 1.09-12.48, P = 0.035] in the original cohort. CONCLUSIONS: Palliative PTR may not offer survival benefits for patients with unresectable metastatic colorectal NENs.

Endoscopic hand suturing using a modified through-the-scope needle holder for mucosal closure after colorectal endoscopic submucosal dissection: Prospective multicenter study (with video).

OBJECTIVES: Endoscopic hand suturing (EHS) is a novel technique for closing a mucosal defect after endoscopic submucosal dissection (ESD). We investigated the technical feasibility of colorectal EHS using a modified flexible through-the-scope needle holder. METHODS: This was a prospective multicenter study conducted at two referral centers between June 2022 and April 2023. This study included colorectal neoplasms 20-50 mm in size located in the sigmoid colon or rectum. A modified flexible through-the-scope needle holder, with an increased jaw width to facilitate needle grasping, was used for colorectal EHS. The primary end-points were sustained closure rate on second-look endoscopy (SLE) performed on postoperative days 3-4 and suturing time for colorectal EHS. Secondary end-points included complete closure rate and delayed adverse events. RESULTS: We enrolled 20 colorectal neoplasms in 20 patients, including four patients receiving antithrombotic agents. The tumor location was as follows: lower rectum (n = 8), upper rectum (n = 2), rectosigmoid colon (n = 4), and sigmoid colon (n = 6), and the median mucosal defect size was 37 mm (range, 21-65 mm). The complete closure rate was 90% (18/20 [95% confidence interval (CI) 68.3-98.8%]), and the median suturing time was 49 min (range, 23-92 min [95% CI 35-68 min]). Sustained closure rate on SLE was 85% (17/20 [95% CI 62.1-96.8%]). No delayed adverse events were observed. CONCLUSION: EHS demonstrated a high sustained closure rate. Given the long suturing time and technical difficulty, EHS should be reserved for cases with a high risk of delayed adverse events.

Recent trends in AI applications for pelvic MRI: a comprehensive review.

Magnetic resonance imaging (MRI) is an essential tool for evaluating pelvic disorders affecting the prostate, bladder, uterus, ovaries, and/or rectum. Since the diagnostic pathway of pelvic MRI can involve various complex procedures depending on the affected organ, the Reporting and Data System (RADS) is used to standardize image acquisition and interpretation. Artificial intelligence (AI), which encompasses machine learning and deep learning algorithms, has been integrated into both pelvic MRI and the RADS, particularly for prostate MRI. This review outlines recent developments in the use of AI in various stages of the pelvic MRI diagnostic pathway, including image acquisition, image reconstruction, organ and lesion segmentation, lesion detection and classification, and risk stratification, with special emphasis on recent trends in multi-center studies, which can help to improve the generalizability of AI.

Rectal volume is correlated with interfractional positional shifts of the prostate gland in dogs receiving radiation therapy.

Variability in prostate gland positioning during RT for prostate tumors is a recognized challenge in both human and veterinary oncology. This retrospective study investigates the interfractional variability in prostate gland positioning in relation to rectal and bladder volumes in dogs undergoing radiation therapy (RT) for prostate tumors. The study tracked 10 dogs undergoing five RT sessions from February 2016 to November 2021, delivering a total of 25 Gy each. Each dog underwent CT scans for treatment simulation, and cone-beam CT (CBCT) images were acquired before each RT. The focus was to analyze the positional shifts of the prostate gland concerning the volumes of the rectum and urinary bladder. The pelvic bones were used as the point of reference. The rectal and bladder volumes were measured before each RT, and shifts in the prostate gland position were calculated by comparing coordinates from planning CT and treatment session images. Findings revealed significant correlations between prostate positional shifts in the dorsal-ventral (repeated measures correlation coefficient of -0.58 [range 00.75-00.33]; P < .001) and cranial-caudal directions (repeated measures correlation coefficient [95%CI] 0.56 [range 0.31-0.74]; P < .001) and rectal volume, while no significant relationship was observed with bladder volume. Shifts in the lateral direction were not correlated with either organ's volume. This study highlights the importance of considering rectal volume in canine prostate tumor RT to minimize positional uncertainties. Maintaining consistent rectal volume may enhance the precision of prostate targeting, potentially influencing the safety of RT.

Charles Boyd Kelsey (1850-1917). The pioneer of rectal surgery in USA.

Charles Boyd Kelsey (1850-1917) was a pioneer rectal surgeon. His surgical career was dedicated in the surgery of the rectum, anus, hemorrhoids, and pelvis. He invented also surgical instruments. He managed to be recognized as a pioneer of Rectal surgery not only in America but worldwide. He was a prolific writer and a famous teacher.