Retroperitoneoscopy of the presacral space in horses: Surgical access and anatomy

BACKGROUND

Surgical approaches to the equine rectum and perirectal area are described in the literature. However, surgeries in this region can be challenging.

OBJECTIVE

To describe the surgical anatomy of the presacral space and to evaluate its access using a retroperitoneoscopic approach.

STUDY DESIGN

Ex vivo experiment.

METHODS

Preliminary dissections were performed in two cadavers to define the boundaries of the presacral space and to determine portal locations for the surgical approach. After that, nine cadavers were used for experimental presacral retroperitoneoscopic procedure in a standing position. Following retroperitoneoscopy, cadavers were dissected to confirm the anatomical structures observed during the endoscopic procedures, to control the location of each portal and to record iatrogenic trauma.

RESULTS

The presacral space was bordered by the vertebral column from the ventral aspect of lumbosacral promontorium to the first coccygeal vertebra dorsally and by the presacral fascia and peritoneum ventrally. Lateral limits were composed of the sacrosciatic ligament and transversalis fascia. Cranial and caudal borders were composed of the peritoneum and coccygeal and levator ani muscles respectively. Retroperitoneoscopic portals were placed between the external anal sphincter and semimembranosus muscles and between the base of the tail and the external anal sphincter muscle through the anococcygeal fascia to enter the space by its caudal border. The retroperitoneal space was reached in all cases and the dorsal and lateral aspects of the rectum were visualised after creation of a working space.

MAIN LIMITATIONS

Use of cadaver specimens do not permit to evaluate the tolerance in living animals and the surgical complications such as rectal damage, haemorrhage and infection.

CONCLUSION

This study provides an anatomical description and surgical access of the presacral space with a minimal invasive approach. Retroperitoneoscopy allows access to the rectum and the dorsal aspect of the pelvis.

EBV-Positive Intravascular Large B-Cell Lymphoma of the Small Intestine: A Case Report and Literature Review

Intravascular large B-cell lymphoma (IVLBCL) is a rare lymphoma that affects the brain, skin, and bone marrow. We describe the case of a 75-year-old man who was admitted to the hospital after 4 h of stomach aches. A thorough physical examination indicated stomach discomfort and skin discoloration. Laboratory tests revealed thrombocytopenia and elevated lactate dehydrogenase levels. A computed tomography scan of the abdomen revealed that the small intestine wall was thickened, edematous, and necrotic. The necrotic small bowel was surgically removed, revealing many little round, homogenous, and unusual cells in the mesenteric vein. In-situ hybridization revealed that these cells were positive for PAX5, CD20, CD79a, CD10, and BCL2, as well as Epstein-Barr virus-encoded small RNA. After 1 week of hospitalization without treatment, the patient was diagnosed with IVLBCL and died of multiple organ dysfunction syndrome. IVLBCL is a rare illness that affects the small intestine and possibly the gastrointestinal system. It has an insidious start, a fast development, and a dismal prognosis. Knowing its clinicopathologic traits helps in understanding the illness, making an early diagnosis, and preventing rapid worsening.

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.

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.

Robotic surgery for deep-infiltrating endometriosis: is it time to take a step forward?

Endometriosis is a chronic debilitating disease that affects nearly 10% of women of the reproductive age. Although the treatment modalities of endometriosis are numerous, surgical excision of the endometriotic implants and nodules remains the sole cytoreductive approach. Laparoscopic excision of endometriosis was proven to be beneficial in improving the postoperative pain and fertility. Moreover, it was also proved to be safe and efficient in treating the visceral localization of deep endometriosis, such as urinary and colorectal endometriosis. More recently, robotic-assisted surgery gained attention in the field of endometriosis surgery. Although the robotic technology provides a 3D vision of the surgical field and 7-degree of freedom motion, the safety, efficacy, and cost-effectiveness of this approach are yet to be determined. With this paper, we aim to review the available evidence regarding the role of robotic surgery in the management of endometriosis along with the current practices in the field.

Nodular hyperplasia of lymphoglandular complexes in dogs: A potential diagnostic pitfall for rectal masses

Lymphoglandular complexes are components of the gut-associated lymphoid tissue that are characterized by submucosal lymphoid aggregates invested by projections of mucosal epithelium. Reports of pathology involving these structures are rare in both human and veterinary literature. Here, the authors report 2 cases of rectal masses excised from dogs following a period of tenesmus and hematochezia. In both animals, the masses were composed of lymphoid tissue closely encompassing tubuloacinar structures. Immunohistochemistry and polymerase chain reaction antigen receptor rearrangement testing demonstrated that the lymphoid population was polyclonal, comprising T and B cells arranged in loosely follicular aggregates centered on the epithelial foci. In light of these findings, a diagnosis of lymphoglandular complex nodular hyperplasia was reported. To the authors' knowledge, this is the first report of this condition in dogs.

A Novel Use of a Schanz Pin-Rectal Foreign Body Extraction: A Case Report

Introduction

Retained rectal foreign bodies (RFBs) can be difficult to extract, forcing the surgeon to get creative. This is the first case report utilizing orthopedic drilling and joystick manipulation techniques for foreign body extraction.

Case Report

A 63-year-old male presented to the emergency department with a pool ball in his rectum for two days. Extraction attempts under anesthesia both transanally and through a low midline laparotomy were unsuccessful due to the patient's pelvic anatomy. Orthopedic surgery was consulted to see if any manipulation or resection of the pelvis might aid in extraction. Ultimately, a Schanz pin was drilled retrogradely from the rectum into the pool ball and successfully manipulated the pool ball out of the patient.

Conclusion

Techniques such as drilling and joystick manipulation are common in orthopedic surgery but rarely used in other surgical fields. This case presented a novel use of a Schanz pin in RFB extraction. Application of orthopedic surgical technique in a colorectal surgery in this case saved the patient from more invasive interventions such as pubic symphysiotomy or ischial tuberosity resection.

Analysis of cell populations in the normal rhesus macaque (Macaca mulatta) lower intestinal tract and diagnostic thresholds for chronic enterocolitis

Rhesus macaques (Macaca mulatta) are used extensively in biomedical research, often with a focus on the gastrointestinal tract, and yet a full characterization of their normal resident intestinal cell populations has not been published. In addition, chronic enterocolitis (CE), also known as idiopathic chronic diarrhea, affects up to 25% of colony-housed rhesus macaques, often requiring euthanasia for welfare concerns and severely limiting their value as a breeding animal or research subject. We aimed to characterize subjective and objective variables in sections of the ileum, cecum, colon, and rectum in 16 healthy rhesus macaques and compare these results with a cohort of 37 animals euthanized for CE to produce relevant diagnostic thresholds and to improve case definitions for future studies. We found neutrophils to be an infrequent but expected component of the large intestinal leukocyte population. Animals with CE had significantly increased total leukocyte populations between crypts in the cecum, colon, and rectum; variable increases in specific cell populations across all levels of the distal intestinal tract; and significantly increased intraepithelial CD3+ T cells in the colon and rectum. Concentrations of enteroendocrine cells, enterochromaffin cells, and intestinal mast cells were not significantly different between healthy and affected individuals. This study characterizes individual leukocyte populations in the rhesus macaque lower intestinal tract, is the first to evaluate rhesus macaque intestinal mast cells, and provides key diagnostic thresholds for evaluating animals with potential CE.

Submucosal Lipoma in the Rectum Found Incidentally During Colonoscopy Screening: A Case Report

Gastrointestinal (GI) tract lipomas are a benign entity of GI tumors. In this case report, we present a 53-year-old patient who was found to have a rectal lipoma incidentally in an asymptomatic middle-aged female during a routine colonoscopy screening. The tumor was excised during colonoscopy and sent for histopathology, which confirmed the diagnosis. We also provide a literature review of GI lipomas, focusing on their occurrence in the rectum.

RAS mutation status in combination with the JSHBPS nomogram may be useful for preoperative identification of colorectal liver metastases with high risk of recurrence and mortality after hepatectomy

PURPOSE

To investigate the prognostic impact of RAS mutations on the Japanese Society of Hepatobiliary and Pancreatic Surgeons (JSHBPS) nomogram score in patients with colorectal cancer liver metastasis (CRLM) following hepatectomy.

METHODS

We included 218 consecutive patients undergoing hepatectomy for CRLM between 2004 and 2020. The JSHBPS nomogram score was calculated using six preoperative clinical factors. The score ranged from 0 to 25, and higher scores indicated greater tumor burden. Associations of RAS mutations with disease-free survival (DFS) and overall survival (OS) by the JSHBPS nomogram score were examined. Multivariable Cox proportional hazard regression models were used to estimate adjusted hazard ratios (HRs) and confidence intervals (CIs).

RESULTS

RAS mutations were detected in 72 (33%) of the 218 patients. Multivariate analyses revealed that RAS mutations were independently associated with poor DFS (HR, 1.93; 95% CI: 1.20-3.10; p = .007) and OS (HR, 2.65; 95% CI: 1.59-4.71; p = .001) compared with wild-type RAS with JSHBPS nomogram scores ≤ 10. However, in patients with scores ≥ 11, the association of RAS mutations with DFS or OS was not statistically significant (p > .08).

CONCLUSION

RAS mutation status in combination with the JSHBPS nomogram may be useful for preoperatively identifying CRLM with high risk of recurrence and mortality after hepatectomy.

Tumor-associated microbiome features of metastatic colorectal cancer and clinical implications

Background

Colon microbiome composition contributes to the pathogenesis of colorectal cancer (CRC) and prognosis. We analyzed 16S rRNA sequencing data from tumor samples of patients with metastatic CRC and determined the clinical implications.

Materials and methods

We enrolled 133 patients with metastatic CRC at St. Vincent Hospital in Korea. The V3-V4 regions of the 16S rRNA gene from the tumor DNA were amplified, sequenced on an Illumina MiSeq, and analyzed using the DADA2 package.

Results

After excluding samples that retained <5% of the total reads after merging, 120 samples were analyzed. The median age of patients was 63 years (range, 34-82 years), and 76 patients (63.3%) were male. The primary cancer sites were the right colon (27.5%), left colon (30.8%), and rectum (41.7%). All subjects received 5-fluouracil-based systemic chemotherapy. After removing genera with <1% of the total reads in each patient, 523 genera were identified. Rectal origin, high CEA level (≥10 ng/mL), and presence of lung metastasis showed higher richness. Survival analysis revealed that the presence of Prevotella (p = 0.052), Fusobacterium (p = 0.002), Selenomonas (p<0.001), Fretibacterium (p = 0.001), Porphyromonas (p = 0.007), Peptostreptococcus (p = 0.002), and Leptotrichia (p = 0.003) were associated with short overall survival (OS, <24 months), while the presence of Sphingomonas was associated with long OS (p = 0.070). From the multivariate analysis, the presence of Selenomonas (hazard ratio [HR], 6.35; 95% confidence interval [CI], 2.38-16.97; p<0.001) was associated with poor prognosis along with high CEA level.

Conclusion

Tumor microbiome features may be useful prognostic biomarkers for metastatic CRC.

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.

Analysis of the Genetic Characteristics and Metastatic Pathways of G1 and G2 Colorectal Neuroendocrine Neoplasms

Objective

G1 and G2 colorectal neuroendocrine neoplasms (NENs) are a group of rare and indolent diseases. We aimed to delineate their genetic characteristics and explore their metastatic mechanisms.

Methods

We used next-generation sequencing technology for targeted sequencing for 54 patients with G1 and G2 colorectal NENs. We delineated their genetic features and compared the genetic characteristics between metastatic NENs and nonmetastatic NENs. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis was utilized to explore their abnormal pathways and study their potential metastatic mechanisms.

Results

We collected 23 metastatic NENs and 31 nonmetastatic NENs. In the whole cohort, the common mutated genes were NCOR2, BRD4, MDC1, ARID1A, AXIN2, etc. The common copy number variations (CNVs) included amplification of HIST1H3D, amplification of HIST1H3E, and loss of PTEN. The KEGG enrichment analysis revealed that PI3K-Akt, MAPK, and Rap1 were the major abnormal pathways. There were significantly different genetic features between metastatic NENs and nonmetastatic NENs. The metastatic NENs shared only 47 (22.5%) mutated genes and 6 (13.3%) CNVs with nonmetastatic NENs. NCOR2, BRD4, CDKN1B, CYP3A5, and EIF1AX were the commonly mutated genes in metastatic NENs, while NCOR2, MDC1, AXIN2, PIK3C2G, and PTPRT were the commonly mutated genes in nonmetastatic NENs. Metastatic NENs presented a significantly higher proportion of abnormal pathways of cell senescence (56.5% vs 25.8%, P = .022) and lysine degradation (43.5% vs 16.1%, P = .027) than nonmetastatic NENs.

Conclusion

G1 and G2 colorectal NENs are a group of heterogeneous diseases that might obtain an increased invasive ability through aberrant cell senescence and lysine degradation pathways.

An Unusual Case of Gastric Heterotopia Presenting as Rectal Prolapse

Heterotopic gastric mucosa (HGM) involving the rectum is an uncommon finding. It is especially rare in young children. Rectal prolapse is an uncommon presentation of HGM. We report a case of HGM in the rectum of a 2-year-old previously healthy girl, who presented with rectal prolapse and painless bleeding. Endoscopic mucosal resection was performed to completely resect the lesion after the patient failed to respond to proton pump inhibitors. This case underscores the importance of considering HGM involving the rectum as a cause of rectal prolapse in young pediatric patients.

Focal hemolymphangioma of the rectum: A case report and literature review

RATIONALE

Gastrointestinal hemolymphangiomas are very rare, especially in the rectum. Only 3 cases of rectal hemolymphangioma, all of which are diffuse lesions, have been reported in the English literature on PubMed. Our case is the first focal lesion of the rectum. It is important for radiologists to correctly identify the imaging features of rectal hemolymphangiomas.

PATIENT CONCERNS

A 51-year-old woman visited our hospital because of intermittent constipation for 3 years.

DIAGNOSES

Colonoscopy revealed a prominent lesion on the left anterior wall of the lower rectum. Transvaginal color Doppler ultrasonography showed that the posterior vaginal wall area had a mixed-echo mass, and blood flow signals of the dots and stripes could be seen. Pelvic magnetic resonance imaging showed that the cystic space-occupying lesion in the region between the left anterior wall of the lower rectum and the posterior wall of the middle and lower vagina had a clear boundary.

INTERVENTIONS

The patient underwent surgery to remove the rectal lesions. The surgical specimen was finally diagnosed as local hemolymphangioma by pathological analysis.

LESSONS

Localized hemolymphangioma of the rectum is very rare, and imaging examination is essential for the diagnosis and evaluation of the extent of lesion invasion.

Splenic flexure mobilization and anastomotic leakage in anterior resection for rectal cancer: A multicentre cohort study

BACKGROUND AND OBJECTIVE

Some colorectal surgeons advocate routine splenic flexure mobilization (SFM) when performing anterior resection for rectal cancer to ensure a tension-free anastomosis. Meta-analyses of smaller studies suggest that this approach does not influence anastomotic leakage rates, but larger multicentre studies are needed to confirm the safety of a selective strategy. The aim of this study is to evaluate the impact of SFM on anastomotic leakage.

METHODS

This is a retrospective multicentre cohort study, comprising 1109 patients operated with anterior resection for rectal cancer in 2014-2018. Exposure was SFM, while anastomotic leakage within a year constituted the outcome. Stratified analyses were performed for type of mesorectal excision and surgical approach, as well as sensitivity analysis considering vascular tie placement. Multivariable Cox regression with hazard ratios (HRs) and 95% confidence intervals (CIs) was employed to adjust for confounding, while multiple imputation was used for missing data.

RESULTS

SFM was performed in 381 patients (34.4%). Anastomotic leakage occurred in 83 (21.8%) and 123 (20.3%) patients operated with and without SFM, respectively. SFM was neither clearly detrimental nor beneficial regarding anastomotic leakage (adjusted HR = 0.82; 95% CI: 0.59-1.15), with no apparent differences for total or partial mesorectal excision and minimally invasive or open surgery. Concurrent high vascular ligation did not impact these results, and there was no evidence of interaction from centers with a more common use of SFM.

CONCLUSIONS

SFM did not seem to influence the risk of anastomotic leakage after anterior resection for rectal cancer, regardless of type of mesorectal excision, use of minimally invasive surgery, or high vascular ligation.

Opium use and risk of colorectal cancer: a multi-center case-referent study in Iran

BACKGROUND

Opium use has been associated with an increased risk of cancers of the lung, oesophagus, and pancreas, and it was recently classified by the International Agency for Cancer Research as carcinogenic to humans. It is not clear whether opium also increases the risk of colorectal cancer (CRC). The aim of our study was to assess the association between various metrics of opium use and the risk of CRC.

METHODS

This case-referent study from seven provinces in Iran comprised 848 CRC cases and 3215 referents. Data on opium use (duration, amount, frequency) and potential confounders were collected by trained interviewers. Multivariable unconditional logistic regression models were used to measure odds ratios (OR) adjusted for age, gender, province, marital status, family history of CRC-linked cancers, consumption of red meat, fruits and vegetables, body shape, occupational physical activity, and socioeconomic status.

RESULTS

Regular opium consumption was not associated with the risk of CRC (OR 0.9, 95% confidence interval, CI: 0.7, 1.2) compared to subjects who never used opium. However, frequent opium use more than twice a day was associated with an increased risk of CRC compared to non-users of opium (OR: 2.0, 95% CI: 1.1, 3.8; p for quadratic trend 0.008).

CONCLUSION

There seems to be no overall association between opium use and CRC, but the risk of CRC might be increased among persons who use opium many times a day.

Peritoneal and Systemic Interleukin-10 as Early Biomarkers for Colorectal Anastomotic Leakage Following Surgery in Colorectal Cancer Patients: A Systematic Review and Meta-Analysis

<b><br>Introduction:</b> Despite advancements in diagnostic methods, the early detection of colorectal anastomotic leakage (CAL) continues to pose challenges. The identification of reliable markers is crucial to reduce patient morbidity and mortality. Cytokines present in drain fluid and systemic cytokine levels have shown promise as predictive markers for CAL; however, additional high-quality evidence is warranted to enhance the reliability and validity of the findings in this field.</br> <b><br>Aim:</b> This systematic review and meta-analysis aimed to assess the significance of peritoneal and serum/plasma interleukin-10 (IL-10) levels in the early detection of CAL in patients undergoing colorectal surgery for colorectal cancer.</br> <b><br>Methods:</b> A comprehensive literature search was conducted in PubMed, Scopus, and Web of Science databases, covering studies published until July 2023. The search aimed to identify relevant studies investigating the levels of plasma/serum and peritoneal IL-10 (or both) in colorectal cancer patients undergoing colorectal surgery, specifically focusing on the presence of CAL. Data on the mean and standard deviation of IL-10 levels in both CAL and non-CAL patients were extracted from the selected studies. Mean differences in IL-10 levels were analyzed for each postoperative day (POD) using the OpenMeta [analyst] software.</br> <b><br>Results:</b> 11 articles were selected for inclusion in this systematic review. Among them, nine articles reported data on peritoneal IL-10 levels, while four articles focused on circulating IL-10 levels. The statistical analysis included four eligible articles that assessed peritoneal IL-10 levels, and the results indicated no significant increase in CAL patients compared to non-CAL patients on any postoperative day (POD). Meta-analysis for circulating IL-10 levels was not feasible.</br> <b><br>Conclusions:</b> Up to now, peritoneal and systemic IL-10 levels cannot be considered as early markers for CAL after colorectal surgery in colorectal cancer patients. More high-quality studies are needed to establish the potential of IL-10 as a reliable marker for detecting anastomotic leakage after colorectal surgery.</br>.

A Rare Case of Primary Extra-Nodal Marginal Zone Lymphoma of Mucosa-Associated Lymphoid Tissue (MALT) in the Rectum

Mucosa-associated lymphoid tissue (MALT) is a unique clinical condition that can manifest in different anatomic locations. In the gastrointestinal tract, it is typically seen in the stomach but is less commonly found in other sites. There have been a few cases in the literature in which primary MALT lymphoma is found in the rectum. We describe a case of a 63-year-old male who presented with rectal pain and bleeding. Colonoscopy revealed a rectal mass, which was excised with a trans-anal approach. Histopathological examination of the biopsy specimen was significant for MALT lymphoma. Therefore, the patient underwent radiation therapy followed by repeat colonoscopies to monitor disease recurrence.

Sporadic Colorectal Tubular Adenomas Thrive in Symbiosis With Underlying Nondysplastic Branching Crypts

BACKGROUND/AIM

Nondysplastic crypt branching (NDCB), mostly asymmetric branching (NDCAB), was previously found beneath the dysplastic epithelium of colorectal tubular adenomas (TA) in Swedish patients. This study examined the frequency of NDCB and NDCAB beneath the dysplastic epithelium of TA, in German patients.

PATIENTS AND METHODS

From a collection of 305 TA, 121 TA fulfilled the prerequisites for inclusion. All NDCB were registered.

RESULTS

Of 673 NDBCs, 572 (85%) NDCABs and 101 (15%) NDCSs, were found beneath the neoplastic tissue in the 121 TA. When the frequency of NDCB was challenged against the TA size, a linear correlation was found in the 121 TA (p<0.05, p=0.020172). Most NDCB were NDCAB (p<0.05, p=0.00001). The frequency of NDCB correlated with increasing TA size, implying that the higher frequency of both NDCB, dysplastic crypt branching, and their dysplastic offspring crypts were the most probable sources of TA enlargement. The frequency of NDCB underneath TA was not influenced by increasing age, sex or TA localization.

CONCLUSION

Similar findings as those reported here were previously found in TA in Swedish patients. The similarity between these two populations, located in disparate geographical areas and subjected to dissimilar microenvironmental conditions suggests that NDBC in TA might be a ubiquitous unreported phenomenon. According to the literature, normal colon cells often harbor somatic mutations. Consequently, NDCB underneath TA may be mutated nondysplastic branching crypts upon which the dysplastic epithelium in TA eventually develops.

Technical aspects of a new approach to intraoperative pelvic neuromonitoring during robotic rectal surgery

It has been found that rectal surgery still leads to high rates of postoperative urinary, fecal, or sexual dysfunction, which is why nerve-sparing surgery has gained increasing importance. To improve functional outcomes, techniques to preserve pelvic autonomic nerves by identifying anatomic landmarks and implementing intraoperative neuromonitoring methods have been investigated. The objective of this study was to transfer a new approach to intraoperative pelvic neuromonitoring based on bioimpedance measurement to a clinical setting. Thirty patients (16 male, 14 female) involved in a prospective clinical investigation (German Clinical Trials Register DRKS00017437, date of first registration 31/03/2020) underwent nerve-sparing rectal surgery using a new approach to intraoperative pelvic neuromonitoring based on direct nerve stimulation and impedance measurement on target organs. Clinical feasibility of the method was outlined in 93.3% of the cases. Smooth muscle contraction of the urinary bladder and/ or the rectum in response to direct stimulation of innervating functional nerves correlated with a change in tissue impedance compared with the pre-contraction state. The mean amplitude (Amax) of positive signal responses was Amax = 3.8%, negative signal responses from a control tissue portion with no stimulation-induced impedance change had an amplitude variation of 0.4% on average. The amplitudes of positive and negative signal responses differed significantly (statistical analysis using two-sided t-test), allowing the nerves to be identified and preserved. The results indicate a reliable identification of pelvic autonomic nerves during rectal surgery.

Decay of HIV RNA in Seminal Plasma and Rectal Fluid in Treatment-Naive Adults Starting Antiretroviral Therapy With Dolutegravir Plus Lamivudine or Bictegravir/Emtricitabine/Tenofovir Alafenamide

BACKGROUND

Decay of HIV in seminal plasma (SP) and rectal fluid (RF) has not yet been described for the antiretroviral combination of dolutegravir (DTG) + lamivudine (3TC).

METHODS

In this randomized multicenter pilot trial, males who were antiretroviral naive were randomized (2:1) to DTG + 3TC or bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF). HIV-1 RNA was measured in blood plasma (BP), SP, and RF at baseline; days 3, 7, 14, and 28; and weeks 12 and 24.

RESULTS

Of 25 individuals enrolled, 24 completed the study (DTG + 3TC, n = 16; BIC/FTC/TAF, n = 8). No significant differences were observed between groups for median decline in HIV-1 RNA from baseline at each time point or median time to achieve HIV-1 RNA <20 copies/mL in BP and SP and <20 copies/swab in RF. HIV-1 RNA decay patterns were compared in individuals receiving DTG + 3TC. Despite significantly higher percentages for changes from baseline in BP, median (IQR) times to HIV-1 RNA suppression were shorter in SP (7 days; 0-8.75) and RF (10.5 days; 3-17.5) than in BP (28 days; 14-84; P < .001).

CONCLUSIONS

Comparable HIV-1 RNA decay in BP, SP, and RF was observed between DTG + 3TC and BIC/FTC/TAF. As shown with triple-drug integrase inhibitor-based regimens, rapid HIV-1 RNA suppression in SP and RF is achieved with DTG + 3TC, despite decay patterns differing from those of BP.

CLINICAL TRIALS REGISTRATION

EudraCT 2019-004109-28.

The Effect of Increasing Bath Temperature on the Contractile Responses of the Large Gut in Adult and Neonate Rats

Introduction Earlier reports on the effect of temperature on gut motility concentrated on experiments conducted on the small intestines of adult animals. The effect of temperature on the large intestine, particularly in neonates, warrants further investigation. The current study investigated the effect of a temperature increase and its mechanism in the colon and rectum of neonate and adult rats. Methods and materials In an organ bath preparation, segments from the colon and rectum were subjected to increasing bath temperatures (37°C-40°C). In other groups, pretreatment with capsazepine (1 µM) and Nω-nitro-l-arginine methyl ester (L-NAME) (100 µM) was done, in different groups, to assess their impact on temperature-induced contractile response. Results Increasing the bath temperature significantly reduced the contractile tension in the colon and rectum. When L-NAME (100 µM)-pretreated segments of the colon and rectum were subjected to different bath temperatures, the contractile tension increased compared to the contractile tension at different bath temperatures without any drug. Capsazepine (1 µM) pretreatment, on the other hand, enhanced the decrease in the contractile tension in the colon and rectum of adult rats compared to the contractile tension produced at different bath temperatures without any drug, while in neonates, capsazepine (1 µM) pretreatment caused a rise in the contractile tension in the rectum with no effect in the colon. Increased bath temperature from 37°C to 40°C increased the contractile frequency in the colon and rectum in both adult and neonate rats. Pretreatment with L-NAME (100 µM) and capsazepine (1 µM) in adults and L-NAME (100 µM) in neonates caused an increase in the contractile frequency in both the colon and rectum; on the other hand, capsazepine pretreatment did not affect the contractile frequency in the colon and rectum of neonate rats compared to the contractile frequency produced at different bath temperatures without any drug. Conclusion The contractile response of rats' large intestines, colon, and rectum to increasing temperatures may involve nitric oxide (NO)-mediated and transient receptor potential vanilloid-1 (TRPV1)-mediated mechanisms. The effects of capsazepine on the colon and rectum of adults and neonates differ, possibly due to the TRPV1-mediated mechanism not developing properly in the neonate and developing later in adulthood.

Long-term risk of repeated surgeries in women managed for endometriosis: a 1,092 patient-series

OBJECTIVE

To assess the long-term risk of repeated surgery in women undergoing complete excision of endometriosis by an experienced surgeon and to identify circumstances leading up to repeat surgery.

DESIGN

Retrospective study based on data recorded in a large prospective database.

SETTING

University Hospital.

PATIENT(S)

A total of 1,092 patients managed for endometriosis, from June 2009 to June 2018, by one surgeon.

INTERVENTION(S)

Complete excision of endometriosis lesions.

MAIN OUTCOME MEASURE(S)

The recording of a repeated surgery linked to endometriosis performed during follow-up.

RESULT(S)

Endometriosis was exclusively superficial in 122 patients (11.2%) and 54 women (5%) had endometriomas without associated deep endometriosis nodules. Deep endometriosis was managed in 916 women (83.9%), leading to infiltration or not of the bowel in 688 (63%) and 228 (20.9%) patients, respectively. A majority of patients were managed for severe endometriosis infiltrating the rectum (58.4%). Mean and median follow-up was 60 months. A total of 155 patients underwent a repeated surgery relating to endometriosis; 108 procedures were required because of recurrences (9.9%), 39 surgeries were related to the management of infertility by assisted reproductive techniques (3.6%), and in 8 surgeries, a direct relationship between surgery and endometriosis was probable but not certain (0.8%). The majority of procedures involved hysterectomy for adenomyosis (n=45, 4.1%). The probability of requiring repeated surgery at 1, 3, 5, 7, and 10 years was 3%, 11%, 18%, 23%, and 28%, respectively. Cox's multivariate model identified postoperative pregnancy and hysterectomy as being statistically significant independent predictors for a reduction in the probability of having a repeated surgery, after adjustment on continuous postoperative amenorrhea, the main localization of the disease, and management for endometriosis infiltrating the rectum during the first surgery.

CONCLUSION(S)

Up to 28% of patients may require a repeated surgical procedure during the 10 years after complete excision of endometriosis. Conservation of the uterus is followed by an increased risk of repeated surgery. The study is based on outcomes resulting from a single surgeon, which limits the generalizability of results.

Is it possible that we can increase the lymph node number in cases with rectum tumor receiving neoadjuvant therapy?

Background

Though the recommended sampled lymph node number in colorectal carcinomas is at least 12, due to shrinkage after preoperative neoadjuvant chemoradiotherapy (NCRT), it can be difficult to attain that number.

Aim

Our aim is to increase the lymph node number by applying alcohol fixation on the formalin-fixed resection materials of the patients that received or not received neoadjuvant therapy and to evaluate the changes in staging due to obtained lymph nodes.

Settings and Design

Non-randomized controlled trial.

Materials and Methods

Lymph node dissection was performed in the resection materials with rectum tumor which were formalin- and afterwards, alcohol-fixed. The number of lymph nodes obtained by both of the methods and status of metastasis were evaluated statistically.

Results

Of the total 76 rectal tumors, 57 had and 19 had not received NCRT. The number of lymph node was adequate in 89.5% cases with no NCRT and in 63.2% cases with NCRT. While no change was observed after the alcohol fixation in the cases fulfilling adequacy criterion among those with no NCRT (p = 1.000), the adequacy rate increased from 63.2% to 87.7% in those with NCRT (p < 0.001). Although statistically insignificant, there was a change in pN stage in eight cases. In three of them, the stage varied from pN0 to pN1c, and in five cases, from pN1a to pN1b.

Conclusion

Using solutions as alcohol during fixation might facilitate the identification of metastatic lymph nodes, might change the stage of the disease and therefore, might affect the patient-based therapy.

Colitis cystica profunda: A report of two cases

Colitis cystica profunda (CCP) is a rare benign disease characterized by mucus-filled cysts in the submucosa. Endoscopic, radiological and histological examinations are not highly specific, which can lead to misdiagnosis, resulting in unnecessary radical surgical resection. This report presents two cases of CCP with their clinical and imaging features.

A case report of heterotopic gastric mucosa in the rectum treated by endoscopic submucosal dissection and a systematic review

RATIONALE

Heterotopic gastric mucosa (HGM) can occur in all segments of the gastrointestinal tract, but rectal is very rare. In recent years, rectal HGM is more often treated by endoscopic resection (ER).

PATIENT CONCERNS

A 28-year-old female was admitted to the hospital with the chief complaint of "a rectal lesion found on physical examination".

DIAGNOSES

Heterotopic gastric mucosa (HGM).

INTERVENTIONS

An endoscopic submucosal dissection (ESD) was performed to completely dissect the lesion.

OUTCOMES

The patient recovered well at 1 month of follow-up and did not suffer from further blood in the stool.

LESSONS

Rectal HGM has acid secretion function and HP can be colonized, causing a variety of symptoms such as abdominal pain, bloody stool, and anal pain and has the potential risk of malignant transformation; resection is the best treatment method, and ESD has its unique advantages and can be promoted in the clinic.

Early-Stage Primary Rectal Melanoma: A Case Report

Malignant primary rectal melanomas (PRM) are rare tumors. Their diagnosis is frequently delayed as these lesions are often mistaken for benign diseases, resulting in extremely poor overall survival. Histological evaluation with special immunohistochemical (IHC) stains is often indispensable for a definitive diagnosis. The main treatment for this condition involves surgical resection. Adjuvant therapy has also been long recommended. We discuss the case of a 60-year-old woman who presented with changes in bowel habits, anal pain, and perineal burning with no bleeding. A digital rectal examination revealed a nodular mass extending 5 cm from the anal verge. Rectosigmoidoscopy demonstrated an ulcerated polypoid tumor extending 4 cm from the anal verge and over 5 cm into the lower rectum. Biopsy and IHC tests confirmed the diagnosis of rectal melanoma. The patient was successfully managed with surgery followed by external beam radiotherapy and a complete response was achieved after 10 months of follow-up.

High Prevalence of Rectal Chlamydia and Gonorrhea Among Men Who Have Sex With Men Who Do Not Engage in Receptive Anal Sex

BACKGROUND

In the United States, annual screening for rectal gonorrhea and chlamydia is only recommended for men who report receptive anal sex (RAS), but other behaviors (e.g., rimming) may lead to rectal Chlamydia trachomatis and Neisseria gonorrhoeae acquisition.

METHODS

We enrolled individuals assigned male sex at birth who reported sex with men and denied RAS in the past 2 years or reported RAS 1 to 2 years ago but were tested and treated since last RAS. Participants enrolled in-person at the Sexual Health Clinic in Seattle, Washington (December 2019-July 2022), or online (July 2021-March 2022). Participants completed a survey that asked about 13 non-RAS behaviors and self-collected a rectal swab for gonorrhea/chlamydia nucleic acid amplification testing. We used log binomial regression to estimate the prevalence of rectal gonorrhea/chlamydia (adjusted prevalence ratio [aPR]) by behavior, adjusting for all other behaviors.

RESULTS

We enrolled 292 participants (247 in-person and 45 online); 277 (95%) had nucleic acid amplification testing results. Rectal gonorrhea/chlamydia test positivity was 14.1% overall: 10.5% for rectal chlamydia and 4.3% for rectal gonorrhea. Most participants (70%) reported ≥1 behavior that involved direct contact with their anus. We observed a higher risk of rectal chlamydia for those who did versus did not report perianal play at 12 months (aPR, 2.39; 95% confidence interval, 1.10-5.22) and 2 months (aPR, 2.21; 95% confidence interval, 1.02-4.79). This was the only behavior significantly associated with testing positive.

CONCLUSIONS

Rectal C. trachomatis and N. gonorrhoeae prevalence was high among men who deny RAS, suggesting other possible routes of acquisition. Rectal screening for those who deny RAS should be made with careful consideration of individual- and population-level effects.

The meaning of R1 resection after endoscopic removal of gastric, duodenal and rectal neuroendocrine tumors

INTRODUCTION

Well-differentiated gastric, duodenal, and rectal neuroendocrine neoplasms (NETs) are rare diseases usually managed by endoscopic treatment. Although several endoscopic techniques are available, the number of patients with incomplete (R1) resection is significant.

AREAS COVERED

This review focuses on the meaning of incomplete R1 findings after endoscopic resection in type I gastric NETs; nonfunctioning, non-ampullary duodenal NETs; and small rectal NETs. Data were identified by MEDLINE database search without publication date limitation.

EXPERT OPINION

An incomplete R1 finding may have no significant impact on a patient's clinical outcome, particularly in small G1 type I gastric NETs, which have an indolent course. A 'stepwise approach,' which uses more advanced endoscopic techniques, or minimally invasive surgery may be justified to achieve complete margin-free resection. This approach must balance the tumor features and the procedure-related risk of complications, particularly in the duodenum, where the role of deep endoscopic resections is limited due to the thin duodenal wall. Gastric and rectal NETs that are incompletely removed after initial resection are more easily amenable to deep endoscopic techniques. However, this might not be necessary for patients with comorbidities, elderly, or both due to the uncertainty of how R1 finding impacts a patient's clinical outcome.

Data mining identifies novel RNA-binding proteins involved in colon and rectal carcinomas

Colorectal adenocarcinoma (COREAD) is the second most deadly cancer and third most frequently encountered malignancy worldwide. Despite efforts in molecular subtyping and subsequent personalized COREAD treatments, multidisciplinary evidence suggests separating COREAD into colon cancer (COAD) and rectal cancer (READ). This new perspective could improve diagnosis and treatment of both carcinomas. RNA-binding proteins (RBPs), as critical regulators of every hallmark of cancer, could fulfill the need to identify sensitive biomarkers for COAD and READ separately. To detect new RBPs involved in COAD and READ progression, here we used a multidata integration strategy to prioritize tumorigenic RBPs. We analyzed and integrated 1) RBPs genomic and transcriptomic alterations from 488 COAD and 155 READ patients, 2) ∼ 10,000 raw associations between RBPs and cancer genes, 3) ∼ 15,000 immunostainings, and 4) loss-of-function screens performed in 102 COREAD cell lines. Thus, we unraveled new putative roles of NOP56, RBM12, NAT10, FKBP1A, EMG1, and CSE1L in COAD and READ progression. Interestingly, FKBP1A and EMG1 have never been related with any of these carcinomas but presented tumorigenic features in other cancer types. Subsequent survival analyses highlighted the clinical relevance of FKBP1A, NOP56, and NAT10 mRNA expression to predict poor prognosis in COREAD and COAD patients. Further research should be performed to validate their clinical potential and to elucidate their molecular mechanisms underlying these malignancies.

RESUSCITATIVE RECTAL BALLOON COMPRESSION COMBINED WITH PELVIC BINDER EFFICIENTLY CONTROLLED FATAL VENOUS HEMORRHAGE IN A HEMODYNAMICALLY UNSTABLE PELVIC FRACTURE CANINE MODEL

ABSTRACT

Objective: This study evaluated the feasibility of a combination of pelvic binder and rectal balloon compression in managing fatal venous hemorrhage in a canine model of pelvic fracture. Methods: Rectums from humans (rectal cancer patients), swine, and canines were retrieved to determine their elasticity by measuring their stress and strain. Canines were selected as the animal model in this study because their rectum demonstrated more reversible strain than swine rectum. Doppler ultrasound was used to assess the effect of rectal balloon volume on the blood flow of pelvic iliac blood vessels in three canines. A rectal balloon of 250 mL was chosen to control pelvic venous bleeding as it could provide a peak effect in reducing the blood flow of bilateral internal iliac veins. Then, the open-book pelvic fracture with fatal bleeding of both internal iliac veins animal model was built. The animals were divided into four groups after the modeled surgery to undergo no treatment, pelvic binder, rectal balloon compression, or a combination of pelvic binder and rectal balloon compression. The treatment efficacy was evaluated based on their survival time, survival rate, blood loss, bleeding rate, infusion rate, blood pH, lactate concentration, the stability of hemodynamics, blood loss, and fluid infusion volume. Results: Our results showed that after the reproducible injuries in both internal iliac veins, the combination of pelvic binder and rectal balloon compression was associated with the best survival rate and survival time compared with the other treatment groups. In addition, the combination of pelvic binder and rectal balloon compression exhibited more stable hemodynamics than the pelvic binder or rectal balloon compression treatment alone. Conclusions: This study demonstrated the potential feasibility of using pelvic binder combined with rectal balloon compression to manage the fatal venous bleeding in pelvic fractures.

Short-Term Outcomes in Patients Undergoing Virtual/Ghost Ileostomy or Defunctioning Ileostomy after Anterior Resection of the Rectum: A Meta-Analysis

BACKGROUND AND OBJECTIVES

Anterior rectal resection (ARR) represents one of the most frequently performed methods in colorectal surgery, mainly carried out for rectal cancer (RC) treatment. Defunctioning ileostomy (DI) has long been chosen as a method to "protect" colorectal or coloanal anastomosis after ARR. However, DI does not rule out risks of more or less serious complications. A proximal intra-abdominal closed-loop ileostomy, the so-called virtual/ghost ileostomy (VI/GI), could limit the number of DIs and the associated morbidity.

MATERIALS AND METHODS

We performed a systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes (PRISMA) guidelines. Meta-analysis was performed by use of RevMan [Computer program] Version 5.4.

RESULTS

The five included comparative studies (VI/GI or DI) covering an approximately 20-year study period (2008-2021). All included studies were observational ones and originated from European countries. Meta-analysis indicated VI/GI as significantly associated with lower short-term morbidity rates related to VI/GI or DI after primary surgery (RR: 0.21, 95% CI: 0.07-0.64, p = 0.006), fewer dehydration (RR: 0.17, 95% CI: 0.04-0.75, p = 0.02) and ileus episodes after primary surgery (RR: 0.20, 95% CI: 0.05-0.77, p = 0.02), fewer readmissions after primary surgery (RR: 0.17, 95% CI: 0.07-0.43, p = 0.0002) and readmissions after primary surgery plus stoma closure surgery (RR: 0.14, 95% CI: 0.06-0.30, p < 0.00001) than the DI group. On the contrary, no differences were identified in terms of AL after primary surgery, short-term morbidity after primary surgery, major complications (CD ≥ III) after primary surgery and length of hospital stay after primary surgery. Conclusions: Given the significant biases among meta-analyzed studies (small overall sample size and the small number of events analyzed, in particular), our results require careful interpretation. Further randomized, possibly multi-center trials may be of paramount importance in confirming our results.

Diode Laser Therapy for Radiation-Induced Vascular Ectasia: Long-Term Results and Cost Analysis

BACKGROUND

Collateral damage to surrounding healthy tissues has been reported in patients who undergo radiation therapy for pelvic malignancies. This study aimed to evaluate the safety, efficacy and cost efficiency of endoscopic diode laser therapy in patients diagnosed with chronic radiation proctitis (CRP).

METHODS

The data of 24 patients (median age 78, range 67-90 years) who presented rectal bleeding and were diagnosed with CRP after undergoing high-dose radiotherapy for prostatic cancer and underwent diode laser therapy were evaluated retrospectively. Non-contact fibers were used in the patients who underwent the procedure without sedation in an outpatient setting.

RESULTS

The patients underwent a median of two sessions; overall, a mean of 1591 J of laser energy per session was used. No complications were noted during or after the procedures. Bleeding was completely resolved in 21/24 (88%) patients, and two patients showed improvement (96%). It was not necessary to suspend antiplatelet (six patients) or anticoagulant (four patients) therapy during the treatment course. The mean cost per session was EUR 473.4.

CONCLUSIONS

The study findings demonstrated that endoscopic non-contact diode laser treatment in CRP patients is safe, effective and cost efficient. For this procedure, antiplatelet and anticoagulant therapy suspension, intraprocedural sedation and hospital admission are not required.

Visualization of Anorectal Lymphatic Flow Using Indocyanine Green Fluorescence Imaging: An Observational Study

BACKGROUND/AIM

Currently, only a small part of functional lymphatic flow around the anorectal region has been anatomically analyzed. Despite the fact that local recurrence is often experienced in the pelvic floor, the functional lymphatic network in this region has rarely been studied due to difficulties in observation. This prospective observational study aimed to observe anorectal lymphatic flow around the pelvic floor using intraoperative indocyanine green fluorescence imaging during laparoscopic or robot-assisted rectal surgery.

PATIENTS AND METHODS

Fourteen patients who underwent laparoscopic (n=7) or robot-assisted (n=7) surgery without any preoperative therapy between April and December 2022 were enrolled. Indocyanine green solution (0.25 mg) was injected into the submucosa at the dentate line of the anterior, posterior, and bilateral walls prior to surgery. During and after total mesorectal excision, lymphatic flow was observed using a near-infrared camera system.

RESULTS

Lymphatic flow visualized by indocyanine green was detected not only in the already-known route from the low rectum to the lateral pelvic lymph nodes via the lateral ligament, but also in the novel route from the low rectum to the surface of the levator ani muscle and hiatal ligament. Fluorescence was widely spread in the pelvic floor between the longitudinal muscle of the low rectum and the surface of the levator ani muscle.

CONCLUSION

Even though the results are preliminary since histological analyses were not performed, a novel widespread lymphatic network on the surface of the levator ani muscle originating from the longitudinal muscle fibers of the low rectum was revealed.

Localized Rectal Amyloidosis with Morphologic Changes from the Submucosal Tumor to the Ulcerative Lesion That Led to Hematochezia During Observation

A 75-year-old woman visited our hospital with constipation. Colonoscopy revealed a submucosal tumor in the rectum. She was followed up as a case of mucosal prolapse syndrome. Six years later, she was referred to our hospital due to hematochezia and abdominal pain. Colonoscopy revealed that the submucosal tumor had an ulcerative appearance with bleeding. Low anterior resection was performed. Amyloid protein deposition was detected from the submucosa to subserosa. Other organs showed no evidence of amyloidosis; we therefore diagnosed the patient with localized rectal amyloidosis. This is a rare case of symptomatic localized rectal amyloidosis whose long-term progression was able to be endoscopically observed.

Transvaginal Resection of a Gastrointestinal Stromal Tumor (GIST) of the Rectum

Gastrointestinal stromal tumors (GISTs) are connective tissue tumors representing a minority of gastrointestinal tumors. A 49-year-old woman was found to have a rectal mass in addition to uterine fibroids during work-up for abnormal uterine bleeding. A peri-rectal mass was again seen during hysterectomy, but definitive resection was deferred. A pelvic MRI suggested a posterior vaginal wall mass. A transvaginal approach was chosen for excision of a solid multi-lobulated mass from the rectovaginal septum space. Frozen section reported uterine leiomyoma, but final pathology confirmed a 10-cm high-risk GIST arising from the rectal muscularis propria, with microscopically positive margins. Patient was started on imatinib therapy. Abdominopelvic resection was offered to decrease the risk of recurrence but was declined. Repeat imaging has shown no obvious distant metastases or residual rectovaginal region mass. The simultaneous and similar presentation of uterine leiomyoma and rectal GIST draws attention to this case.

Association between Dynamic Contrast-Enhanced MRI Parameters and Prognostic Factors in Patients with Primary Rectal Cancer

BACKGROUND

To evaluate the association between perfusion parameters derived from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) with prognostic factors in primary rectal cancer patients.

METHODS

A sample of 51 patients with pathologically proven rectal adenocarcinoma through surgery were retrospectively enrolled. All the patients underwent preoperative DCE-MRI including 3D-spoiled gradient echo. Two radiologists determined the tumor border after radiologic-pathologic correlation and drew regions of interest. The perfusion parameters, including the volume transfer constant (K^trans), were calculated under the extended Toft model. The prognostic factors included TN stage, circumferential resection margin, extramural venous invasion, Kirsten-ras mutation, tumor size, carcinoembryonic antigen, and tumor differentiation. The association was assessed via correlation or t-test. For significant prognostic factors, receiver operating characteristic (ROC) curve analyses were performed to estimate the diagnostic predictive values.

RESULTS

K^trans only showed a significant difference according to tumor differentiation, between the well-differentiated (n = 6) and moderately differentiated (n = 45) groups (0.127 ± 0.032, 0.084 ± 0.036, p = 0.036). The AUC was 0.838 (95% CI, 0.702-0.929), and the estimated accuracy, sensitivity, and specificity were 87%, 90%, and 60%, respectively.

CONCLUSIONS

K^trans showed a significant difference based on tumor differentiation, which may be conducive to prediction of prognosis in primary rectal cancer.

Urogenital tract and rectal microbiota composition and its influence on reproductive outcomes in infertile patients

Introduction

Microbiota in the human body are closely related to human diseases. Female urogenital tract and rectal microbes have been considered as important factors affecting female pregnancy, but the mechanism is unknown.

Methods

Cervical, vaginal, urethral, and rectal swabs were collected from 22 infertile patients and 10 controls, and follicular fluid was extracted from 22 infertile patients. The microbial composition of different sampling sites of infertile patients was examined. By comparing the microbial composition difference between infertile patients and controls and combining bioinformatics methods to analyze the potential impact of the female urogenital tract (cervical, vaginal and urethral) and rectal microbial diversity on female infertility and pregnancy outcomes.

Results

Lactobacillus predominated in the female urogenital tract, but its abundance decreased in infertile patients, whereas the abundance of Gardnerella and Atopobium increased. The microbial changes in the urethra had the same trend as that in the vagina. Compared with healthy controls, the cervical and rectal microbial diversity of infertile patients were significantly increased and decreased, respectively. There might be interactions between microbes in different parts of female. Geobacillus thermogeniticans was enriched in the urogenital tract and rectum of infertile patients, and has a good predictive effect on infertility. Compared with infertile patients, L. johnsonii was enriched in the vagina, urethra, and intestine of the control group. L. acidophilus in follicular fluid might be associated with Non-pregnancy.

Conclusion

This study found that the microbial composition of infertile patients was changed compared with that of healthy people. The translocation of Lactobacillus between the rectum and urogenital tract might play a protective barrier role. The changes of Lactobacillus and Geobacillus might be related to female infertility or pregnancy outcome. The study provided a theoretical basis for the future treatment of female infertility from the perspective of microorganisms by detecting the microbial changes associated with female infertility.

The frequency of dysplastic branching crypts in colorectal polypoid tubular adenomas

Dysplastic crypt branching (DCB) was recently found in ulcerative colitis-associated dysplasia. The aim was to assess the frequency and the branching phenotype of DCB in polypoid colorectal tubular adenomas (TA). A total of 3956 DCB were found in the 139 TA: 98% were in asymmetric branching (DCAB) and the remaining 2% in symmetric branching (DCSB). A linear correlation was found between DCB frequency and the increasing digital size in TA (p < .05). Using a digital ruler, adenomas were divided into small TA (<5 mm) and larger TA (≥5 mm). The difference between the frequency of DCB in small TA (n = 75) vs. larger TA (n = 64), was significant (p < .05). DCB frequency was not influenced by age, gender or TA localization. In the normal colorectal mucosa (≈2 m² ), only occasional CSB is found and no CAB. And yet, multiple DCB (mean 16.7 DCB), mostly DCAB, was found in small TA, occupying <5 mm of the mucosal area. In larger TA, as many as 42.1 DCB (mean), mostly DCAB, occurred in merely 7.8 mm (mean) of the colon mucosa. Thus it is suggested that DCB is a standard histologic element of TA. The natural expansion of the adenomatous tissue in larger TA appears to be follow on from newly produced, mostly DCAB, by DCSB and by the accumulation of their dysplastic offspring's progenies. The findings strongly suggest that DCB is a central microstructure in the histological events unfolding in polypoid colorectal TA.

Average Daily Gain in Lambs Weaned at 60 Days of Age Is Correlated with Rumen and Rectum Microbiota

Colonization of gastrointestinal microbiota in mammals during early life is vital to host health. The objective of this study was to investigate whether lambs with high and low ADG have a different rumen and rectum microbial community. Thus, we investigated potential relationships between rumen and rectum microbiota and average daily gain (ADG) in weaned lambs. Sixteen lambs with similar body weights (7.63 ± 1.18 kg) were selected at 30 days of age. At 60 days of age, lambs were weaned, and ADG was calculated from 60 to 90 days. Then, two groups were generated: higher ADG (HG, 134.17 ± 13.48 g/day) and lower ADG (LG, 47.50 ± 19.51 g/day). Microbiota was evaluated at 30, 60, and 90 days of age. The final live weight and ADG at 90 days of age was higher (p < 0.05) in the HG group compared to the LG group. The maturity of bacterial and fungal communities was increased (p < 0.05) in the HG group for the 30 days vs. 90 days comparison and 60 days vs. 90 days comparison. Linear discriminant analysis effect size (LEfSe) analysis revealed a total of 18 bacterial biomarkers that are ADG-specific in the rumen and 35 bacterial biomarkers in the rectum. Meanwhile, 15 fungal biomarkers were found in the rumen and 8 biomarkers were found in the rectum. Our findings indicated that ADG is related to the rumen and rectum microbiota in lambs.

The role of rectal ultrasound in children with functional constipation

AIM

The study aimed primarily to compare the transverse rectal diameter in children with functional constipation (FC) and children without constipation in different age groups, and between cases of constipation at baseline and after treatment. Secondary aim was to determine factors that could affect the transverse rectal diameter.

METHODS

A controlled prospective study, including a total of 100 children between the ages of 2 and 11 years, who were divided into 50 patients suffering from constipation according to Rome IV criteria and 50 age- and sex-matched controls. Transverse rectal diameter was measured at presentation, and after 3 months of laxative therapy and behavioural modification.

RESULTS

Initial rectal diameter was significantly different between cases (3.55 cm (interquartile range, IQR), 3.2-4) and controls (2.3 cm (IQR, 1.8-2.5)), P value < 0.001, and it was also significantly different between those above and below 4 years, so a separate cut-off point for diagnosis of constipation was suggested being >3 cm for the former and >2.5 cm for the latter. After 3 months of follow-up, rectal diameter significantly reduced to become 2.6 (IQR, 2-2.8), P value < 0.001. Duration of symptoms positively correlated with rectal diameter.

CONCLUSIONS

Ultrasound measurement of rectal diameter is an important tool to diagnose and follow-up functional constipation in children. Different values of rectal diameter are found between those above and below 4 years of age.

Comparative genomics and phenotypic studies to determine site-specificity of Escherichia coli in the lower gastrointestinal tract of humans

Escherichia coli (E. coli) is an important commensal in the human gut; however, it is unknown whether strains show site-specificity in the lower gut. To investigate this, we assessed genotypic and phenotypic differences in 37 clone pairs (two strains with very similar multiple locus variable-number-tandem-repeat analysis [MLVA] profiles) of E. coli isolated from mucosal biopsies of two different gut locations (terminal ileum and rectum). The clone pairs varied at the genomic level; single nucleotide polymorphisms (SNPs) were common, multiple nucleotide polymorphisms (MNPs) were observed but less common, and few indels (insertions and deletions) were detected. The variation was higher in clone pairs that are associated with non-human-associated sequence types (ST) compared to human-associated STs, such as ST95, ST131, and ST73. No gene(s) with non-synonymous mutations were found to be commonly associated with either the terminal ileum or the rectal strains. At the phenotypic level, we identified the metabolic signatures for some STs. Rectum strains of some STs showed consistently higher metabolic activity with particular carbon sources. Clone pairs belonging to specific STs showed distinct growth patterns under different pH conditions. Overall, this study showed that E. coli may exhibit genomic and phenotypic variability at different locations in the gut. Although genomics did not reveal significant information suggesting the site-specificity of strains, some phenotypic studies have suggested that strains may display site-specificity in the lower gut. These results provide insights into the nature and adaptation of E. coli in the lower gut of humans. To the best of our knowledge, no study has investigated or demonstrated the site-specificity of commensal E. coli in the human gut.

A rectal gastrointestinal stromal tumor case accompanied by elevated CEA mimicking rectal carcinoma on 18F-FDG PET/CT

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasm arising from gastrointestinal tract and can be benign or malignant. Rectal GISTs are rare and have poor prognosis. We here reported an older male who presented with features of distending discomfort in the rectum and pain in the anus due to a large rectal tumor. Physical examinations detected a mass in the rectum without blood staining on the gloved finger. Carcinoembryonic antigen (CEA) was found to be slightly elevated and the prostate-specific antigen level was normal. ¹⁸F-FDG PET/CT showed a soft tissue density mass at the bottom of the pelvic, with an unclear boundary to the surroundings with the significantly increased FDG uptake (SUVmax 17.5). Although a rectal carcinoma was suspected based on the finding of PET/CT and CEA, the histopathological examination confirmed the diagnosis of the malignant GIST of the rectum. The patient was then treated with imatinib and on follow-up regularly. In this case, ¹⁸F-FDG PET/CT shows the advantage of visualizing both primary and metastatic lesions and provides valuable information for the diagnosis, staging, evaluation, and prognosis of GIST.

Sessile serrated lesion presenting as large pedunculated polyp in the rectum: A case report

RATIONALE

Sessile serrated lesions (SSLs) are serrated polyps (SP) with the typical serrated architecture of the crypt lining epithelium. SSL has an important clinical implication because they are recognized as precursor lesion of sporadic colorectal cancer (CRC) through "serrated pathway." SSLs usually appear flat to sessile, and are located in the right colon.

PATIENT CONCERNS

A 69-year-old man was referred to a tertiary medical center because of intermittent hematochezia for 2 years.

DIAGNOSIS

Colonoscopy revealed a large, pedunculated polyp in the rectum. The polyp surface was slightly reddish in color and the elongated stalk was covered with almost normal mucosa. Histopathological examination of the resected specimens revealed the typical features of SSL with low-grade dysplasia.

INTERVENTION

Endoscopic mucosal resection using a detachable snare was performed on the tumor for definite diagnosis and treatment.

OUTCOMES

There was no evidence of immediate or delayed bleeding after endoscopic mucosal resection, and the hemoglobin level normalized after a 1-year follow-up.

LESSONS

We report a rare case of a large pedunculated polyp with typical histological features of SSLs in the rectum. Endoscopists should always consider SSLs at any location even with unusual morphological findings.

A Race-Specific, DNA Methylation Analysis of Aging in Normal Rectum: Implications for the Biology of Aging and Its Relationship to Rectal Cancer

Approximately 90% of colorectal cancer (CRC) develop over the age of 50, highlighting the important role of aging in CRC risk. African Americans (AAs) shoulder a greater CRC burden than European Americans (EA) and are more likely to develop CRC at a younger age. The effects of aging in AA and EA normal rectal tissue have yet to be defined. Here, we performed epigenome-wide DNA methylation analysis in the first, large-scale biracial cohort of normal rectum (n = 140 samples). We identified increased epigenetic age acceleration in EA than AA rectum (p = 3.91 × 10^-4) using linear regression. We also identified differentially methylated regions (DMRs) associated with chronological aging in AA and EA, separately using DMRcate. Next, a consensus set of regions associated with cancer was identified through DMR analysis of two rectal cancer cohorts. The vast majority of AA DMRs were present in our analysis of aging in rectum of EA subjects, though rates of epigenetic drift were significantly greater in AA (p = 1.94 × 10^-45). However, 3.66-fold more DMRs were associated with aging in rectum of EA subjects, many of which were also associated with rectal cancer. Our findings reveal a novel relationship between race, age, DNA methylation and rectal cancer risk that warrants further investigation.

18F-FDG PET/CT imaging of primary malignant melanoma of rectum with liver metastases mimicking rectum cancer: case report and literature review

Malignant melanoma (MM) is an aggressive malignant tumor, which mostly occurs on the skin, uvea, etc. The mucosal MM accounts for a small proportion of all MM and can occur in the digestive tract. Primary MM of the digestive tract is rare and can be found in the middle and lower third of the esophagus and the rectum containing melanocytes. Primary rectal MM often occurs in middle-aged and elderly women, with rapid progress and strong invasion. We report a case of a 61-year-old man diagnosed with primary malignant melanoma of the rectum with liver metastases mimicking rectum cancer. ¹⁸F-FDG PET/CT showed the rectal wall was markedly thickened with a high metabolic level (SUVmax 10.6) and the boundary between the lesions and the prostate was unclear. In addition, increased FDG uptake were found in multiple lymph nodes, lung, liver, and bones, suggesting metastasis. In this case, ¹⁸F-FDG PET/CT shows the advantage of evaluating the whole-body situation and provides valuable information for the diagnosis, tumor stage, evaluation of treatment efficacy, and prognosis of MM.

Severe lower gastrointestinal bleeding caused by rectal Dieulafoy's lesion: Case reports and literature review

RATIONALE

Dieulafoy's lesion are relatively rare and can cause severe gastrointestinal bleeding. A Dieulafoy's lesion is defined as an artery that erodes the overlying epithelium without the presence of an ulcer. Bleeding in Dieulafoy's lesion predominantly involves the proximal stomach and upper gastrointestinal tract and is rarely observed in the lower gastrointestinal tract.

PATIENT CONCERNS

Case 1 was a 58-year-old woman complaining of sudden headache and vomiting who was diagnosed with subarachnoid hemorrhage. She underwent transcatheter embolization for intracranial aneurysm treatment but had an acute profuse hematochezia on the 11th day of admission. Case 2 was a 63-year-old man admitted to the respiratory intensive care unit because of fever with altered consciousness level for a week. He was diagnosed with advanced lung cancer that had metastasized to multiple organs one month prior. On the third day of admission, he had an attack of profuse hematochezia, and quickly developed shock and apathy.

DIAGNOSIS

Both patients were diagnosed with actively bleeding rectal Dieulafoy's lesion by bedside emergency colonoscopy.

INTERVENTIONS

Endoscopic hemostatic clipping was performed in 2 patients.

OUTCOMES

Hemostasis was successfully achieved in these 2 patients, and there was no recurrence of symptoms during follow-up.

CONCLUSIONS

We propose that hemostatic clipping is one of the options in the treatment of rectal Dieulafoy's lesions.