Statin use and site-specific risk of colorectal cancer in individuals with hypercholesterolemia from the National Health Insurance Service-National Health Screening Cohort (NHIS-HEALS)

BACKGROUND AND AIMS

We investigated the association between statin use and site-specific risk of colorectal cancer in individuals with hypercholesterolemia.

METHODS AND RESULTS

This study is based on the National Health Insurance Service-National Health Screening Cohort, conducted during 2002-2015. Statin users were classified as high and low users according to medication possession ratio (MPR). Statin nonusers comprised participants who did not use statins during the entire follow-up period. In total, 17,737 statin users and 13,412 statin nonusers were included in the analysis, with a median follow-up period of 12.7 years. Cox proportional hazards regression models were adopted after stepwise adjustment for confounders to investigate prospective association between statin usage and colorectal cancer risk. In total, 378 (2.3%) of 16,588 male participants and 239 (1.6%) of 14,561 female participants had colorectal cancer during the follow-up period. Compared to nonusers, fully adjusted hazard ratios (HRs) (95% confidence intervals [95% CIs]) for colorectal cancer risk in high statin users were 0.56 (0.42-0.75) in men and 0.64 (0.46-0.90) in women. In men, the fully adjusted HRs for proximal and rectal cancer for high users were 0.29 (0.15-0.56) and 0.52 (0.35-0.78), respectively, compared to those for nonusers. In women, statistical significance was seen only in rectal cancer (HR 0.43 [0.25-0.72]) but not in proximal or distal colon cancer.

CONCLUSIONS

High statin users with hypercholesterolemia were associated with lower risk of overall colorectal cancer, especially proximal colon cancer in men and rectal cancer in both sexes.

Feasibility of Adopting the "Step-up Approach" in Managing Necrotizing Pancreatitis-induced Pancreatic-colonic Fistula

Managing acute pancreatitis is clinically challenging because of the generally poor patient condition, the variety of treatment options depending on the severity and complications, and the uncertainty of outcomes. Recently, the step-up approach, which involves less invasive initial treatment and more invasive subsequent treatment, where necessary, has been proposed as the mainstay of managing pancreatitis. This paper presents a case of a 57-year-old man with severe acute pancreatitis, who developed an unexpected fistula in the rectum, which was treated successfully using the step-up approach. In managing this case, the authors faced clinical challenges in determining the infection of necrotic tissue in the early phase of the disease, the optimal timing and method of drainage, and the fistula closure or repair technique. Successful management of this case using the step-up approach validated current recommendations and suggests that it is a reasonable treatment strategy for pancreatic-colonic fistulas. This case also highlights the importance of an awareness that pancreatitis-associated complications can develop in an unexpected manner.

Heterogeneity of Colorectal Cancer Risk Factors by Anatomical Subsite in 10 European Countries: A Multinational Cohort Study

BACKGROUND & AIMS

Colorectal cancer located at different anatomical subsites may have distinct etiologies and risk factors. Previous studies that have examined this hypothesis have yielded inconsistent results, possibly because most studies have been of insufficient size to identify heterogeneous associations with precision.

METHODS

In the European Prospective Investigation into Cancer and Nutrition study, we used multivariable joint Cox proportional hazards models, which accounted for tumors at different anatomical sites (proximal colon, distal colon, and rectum) as competing risks, to examine the relationships between 14 established/suspected lifestyle, anthropometric, and reproductive/menstrual risk factors with colorectal cancer risk. Heterogeneity across sites was tested using Wald tests.

RESULTS

After a median of 14.9 years of follow-up of 521,330 men and women, 6291 colorectal cancer cases occurred. Physical activity was related inversely to proximal colon and distal colon cancer, but not to rectal cancer (P heterogeneity = .03). Height was associated positively with proximal and distal colon cancer only, but not rectal cancer (P heterogeneity = .0001). For men, but not women, heterogeneous relationships were observed for body mass index (P heterogeneity = .008) and waist circumference (P heterogeneity = .03), with weaker positive associations found for rectal cancer, compared with proximal and distal colon cancer. Current smoking was associated with a greater risk of rectal and proximal colon cancer, but not distal colon cancer (P heterogeneity = .05). No heterogeneity by anatomical site was found for alcohol consumption, diabetes, nonsteroidal anti-inflammatory drug use, and reproductive/menstrual factors.

CONCLUSIONS

The relationships between physical activity, anthropometry, and smoking with colorectal cancer risk differed by subsite, supporting the hypothesis that tumors in different anatomical regions may have distinct etiologies.

Pneumatic Colorectal Injury Caused by High Pressure Compressed Air

The pneumatic colorectal injury caused by high pressure compressed air are rare and can be fatal. Herein, we present a case of 45-year-old male who developed sudden onset of severe abdominal pain after cleaning the dust on his pants with high pressure compressed air gun dust cleaner. Emergent exploratory laparotomy was done which findings are a huge rectal perforation with multiple serosal and subserosal tear in sigmoid to splenic flexure of colon. Anterior resection with left hemicolectomy, and temporary transverse colostomy was performed. Postoperative course was uneventful. Recently, prognosis is generally favorable because of prompt diagnosis and emergent surgical management.

Iatrogenic ureteral injuries and their prevention in colorectal surgery: results from a nationwide survey

AIM

Iatrogenic ureteral injury (IUI) occurs rarely during colorectal surgery but is associated with significant mortality, morbidity and medicolegal issues. Few cases are reported, and recommendations regarding prevention are lacking. The aim of this study is to describe the current state of practice regarding IUI and its prevention among general surgeons in Switzerland.

METHOD

All Swiss general surgeons who are members of either the Swiss Association of Laparoscopic and Thoracoscopic Surgery or the Swiss Surgical Society were invited to participate in an anonymous online survey. Demographics, surgical practice, rate of IUI and methods used to prevent IUI were investigated.

RESULTS

All participants were board-certified general surgeons, 63.4% were certified visceral surgeons and 17.9% were certified colorectal surgeons. The mean level of experience in colorectal surgery was 15.6 ± 9.2 years. Formal ureter identification was considered mandatory during sigmoid or rectal surgery by 83.7% of participants, and 31.7% considered identification of the right ureter during right colectomy to be mandatory. In total, 61.8% of the participants and 78.4% of surgeons with more than 20 years of experience had encountered at least one IUI. Prophylactic ureteral stenting was considered useful in complex procedures by 93.5% of participants, and 56.9% had used stents at least once in the past 12 months. Noninvasive techniques for identifying ureters would be considered in regular daily practice by 54.5% of the participants.

CONCLUSION

Most general surgeons experience IUI. Ureter identification is widely integrated in colorectal procedures. Prophylactic stenting is widely used for difficult cases. Noninvasive methods to improve ureter identification are now needed.

Influence of adjuvant antibiotics on fistula formation following incision and drainage of anorectal abscesses: a systematic review protocol

BACKGROUND

Development of fistula-in-ano following incision and drainage (I&D) of anorectal abscesses occurs in over 30% of patients. It is associated with significant patient morbidity and societal cost. The use of antibiotics following drainage is controversial, with randomized controlled trials reporting opposing conclusions regarding their influence on the rate of fistula formation. Given the significant burden associated with their development, it is imperative to determine strategies to minimize their occurrence. The objective of this review is to summarize the available evidence on the role of antibiotics following I&D of anorectal abscesses on fistula formation. Secondary objectives include determining if antibiotics are associated with morbidity, repeat presentation to the emergency department, and requirement for reoperation.

METHODS/DESIGN

MEDLINE, EMBASE, CINAHL, Cochrane Central Registry of Controlled Trials, http://apps.who.int/trialsearch , and clinicaltrials.gov will be searched to identify published and ongoing unpublished interventional and observational studies evaluating the role of antibiotics post I&D on the incidence of fistula formation. There will be no restriction on language, date, or journal. Title and abstracts as well as full texts will be screened in duplicate based on inclusion and exclusion criteria. The Cochrane Risk of Bias tool and ROBINS-I will be used to assess risk of bias in randomized and non-randomized studies, respectively. Our primary outcome is the incidence of fistula formation; secondary outcomes include morbidity, representation to ED, and reoperation. Study heterogeneity will be calculated with Cochran's Q test, P value, and I 2 index. SASS (version 9.4) will be used for meta-analysis.

DISCUSSION

This is the first study to review the available evidence on adjuvant antibiotics and incidence of fistula formation following I&D of anorectal abscesses.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42018092044.

Rectal Invasion by Prostatic Adenocarcinoma That Was Initially Diagnosed in a Rectal Polyp on Colonoscopy

Despite anatomical proximity, prostatic adenocarcinoma with rectal invasion is extremely rare. We present a case of rectal invasion by prostatic adenocarcinoma that was initially diagnosed from a rectal polyp biopsied on colonoscopy in a 69-year-old Korean man. He presented with dull anal pain and voiding discomfort for several days. Computed tomography revealed either prostatic adenocarcinoma with rectal invasion or rectal adenocarcinoma with prostatic invasion. His tumor marker profile showed normal prostate specific antigen (PSA) level and significantly elevated carcinoembryonic antigen level. Colonoscopy was performed, and a specimen was obtained from a round, 1.5 cm, sessile polyp that was 1.5 cm above the anal verge. Microscopically, glandular tumor structures infiltrated into the rectal mucosa and submucosa. Immunohistochemically, the tumor cells showed alpha-methylacyl-CoA-racemase positivity, PSA positivity, and caudal-related homeobox 2 negativity. The final diagnosis of the rectal polyp was consistent with prostatic adenocarcinoma. Here, we present a rare case that could have been misdiagnosed as rectal adenocarcinoma.

Colitis cystica profunda of the rectum with adenomatous dysplastic features: Radiologic-pathologic correlation

Colitis cystica profunda is a rare nonneoplastic condition characterized by the presence of mucus-containing cysts in the submucosa of the right colon and rectum. The etiology is unclear, with a few cases reported in the literature. The presenting symptoms and signs may mimic colorectal adenocarcinoma. We report a case of colitis cystica profunda localized in the rectum, investigated by colonoscopy, CT, MRI, and subsequently surgically treated.

Anatomy of the smooth muscle structure in the female anorectal anterior wall: convergence and anterior extension of the internal anal sphincter and longitudinal muscle

AIM

The anatomy of the region between the vagina and anal canal plays an essential role when performing a proctectomy for low-lying tumours. However, the anatomical characteristics of this area remain unclear. The purpose of the present study was to clarify the configuration, and both lateral and inferior extensions, of the muscle bundles in the anorectal anterior wall in females.

METHODS

Using cadaveric specimens, macroscopic anatomical and histological evaluations were conducted at the anatomy department of our institute. Macroscopic anatomical specimens were obtained from six female cadavers. Histological specimens were obtained from eight female cadavers.

RESULTS

The smooth muscle fibres of the internal anal sphincter and longitudinal muscle extended anteriorly in the anorectal anterior wall of females and the muscle bundles showed a convergent structure. The anterior extending smooth muscle fibres merged into the vaginal smooth muscle layer, distributed subcutaneously in the vaginal vestibule and perineum and spread to cover the anterior surface of the external anal sphincter and the levator ani muscle. Relatively sparse space was observed in the region anterolateral to the rectum on histological analysis.

CONCLUSION

Smooth muscle fibres of the rectum and vagina are intermingled in the median plane, and there is relatively sparse space in the region anterolateral to the rectum. Therefore, when detaching the anorectal canal from the vagina during proctectomy, an approach from both the lateral sides should be used.

Fecal evacuation disorders in anal fissure, hemorrhoids, and solitary rectal ulcer syndrome

The causative factors for hemorrhoids, anal fissure, and solitary rectal ulcer syndrome (SRUS) are poorly understood. The study was done to identify the prevalence of fecal evacuation disorders in patients with anal fissure, hemorrhoids, and SRUS using anorectal manometry (ARM). Retrospective analysis of ARM data from three centers across India was done. Baseline demographic details and symptoms pertaining to bowel movements were noted. Limited colonoscopy details pertaining to hemorrhoids, fissure-in-ano, and SRUS were noted. The patients were divided into two groups-group I (those with fissure, hemorrhoids, or solitary rectal ulcer) and group II (normal study). ARM parameters of resting anal pressure, squeeze pressure, dyssynergic defecation, and abnormal balloon expulsion were compared between the two groups. Sub-analysis was done for ARM metric differences between those with hemorrhoids, chronic fissure, and SRUS. Appropriate statistical tests were used. A p-value of < 0.05 was considered significant. There were more men in group I (87%; p-value 0.01) with a higher resting anal pressure (80 vs. 69 mmHg, p-value 0.03). Functional evacuation disorders (p < 0.0001), dyssynergic defecation (77.2% vs. 46.8%, p < 0.0001) and abnormal balloon expulsion (66.7% vs. 20.3%, p < 0.0001) were significantly higher in group I. These were significantly more common in patients with anal fissure and SRUS compared to those with hemorrhoids (p-value 0.028). Functional evacuation disorders are frequently noted in patients with hemorrhoids, anal fissure, and SRUS.

Interfraction variation and dosimetric changes during image-guided radiation therapy in prostate cancer patients

Purpose

The aim of this study was to identify volume changes and dose variations of rectum and bladder during radiation therapy in prostate cancer (PC) patients.

Materials and Methods

We analyzed 20 patients with PC treated with helical tomotherapy. Daily image guidance was performed. We re-contoured the entire bladder and rectum including its contents as well as the organ walls on megavoltage computed tomography once a week. Dose variations were analyzed by means of Dmedian, Dmean, Dmax, V₁₀ to V₇₅, as well as the organs at risk (OAR) volume. Further, we investigated the correlation between volume changes and changes in Dmean of OAR.

Results

During treatment, the rectal volume ranged from 62% to 223% of its initial volume, the bladder volume from 22% to 375%. The average Dmean ranged from 87% to 118% for the rectum and 58% to 160% for the bladder. The Pearson correlation coefficients between volume changes and corresponding changes in Dmean were -0.82 for the bladder and 0.52 for the rectum. The comparison of the dose wall histogram (DWH) and the dose volume histogram (DVH) showed that the DVH underestimates the percentage of the rectal and bladder volume exposed to the high dose region.

Conclusion

Relevant variations in the volume of OAR and corresponding dose variations can be observed. For the bladder, an increase in the volume generally leads to lower doses; for the rectum, the correlation is weaker. Having demonstrated remarkable differences in the dose distribution of the DWH and the DVH, the use of DWHs should be considered.

Learning curve of enhanced recovery after surgery program in open colorectal surgery

BACKGROUND

Enhanced recovery after surgery (ERAS) reduces hospitalization and complication following colorectal surgery. Whether the experience of multidisciplinary ERAS team affects patients’ outcomes is unknown.

AIM

To evaluate and establish a learning curve of ERAS program for open colorectal surgery.

METHODS

This was a review of prospectively collected database of 380 “unselected” patients undergoing elective “open” colectomy and/or proctectomy under ERAS protocol from 2011 (commencing ERAS application) to 2017 in a university hospital. Patients were divided into 5 chronological groups (76 cases per quintile). Surgical outcomes and ERAS compliance among quintiles were compared. Learning curves were calculated based on criteria of optimal recovery: defined as absence of major postoperative complications, discharge by postoperative day 5, and no 30-d readmission.

RESULTS

Hospitalization more than 5 d occurred in 22.6% (n = 86), major complication was present in 2.9% (n = 11) and 30-d readmission rate was 2.4% (n = 9) accounting for unsuccessful recovery of 25% (n = 95). Conversely, the overall rate of optimal recovery was 75%. The optimal recovery significantly increased from 57.9% in 1^st quintile to 72.4%-85.5% in the following quintiles (P < 0.001). Average compliance with ERAS protocol gradually increased over the time - from 68.6% in 1^st quintile to 75.5% in 5^th quintile (P < 0.001). The application of preoperative counseling, nutrition support, goal-directed fluid therapy, O-ring wound protector and scheduled mobilization significantly increased over the study period.

CONCLUSION

A number of 76 colorectal operations are required for a multidisciplinary team to achieve a significantly higher rate of optimal recovery and high compliance with ERAS program for open colorectal surgery.

Long-term control with chemoradiation of initially metastatic mixed adenoneuroendocrine carcinoma of the rectum: a case report

BACKGROUND

Mixed adenoneuroendocrine carcinomas are highly malignant tumors with both adenocarcinomatous and neuroendocrine components. They can originate in any organ but are more common in the rectum. Due to their rarity, current treatment recommendations for mixed adenoneuroendocrine carcinoma are based on limited data and follow general guidelines for the management of adenocarcinomas and neuroendocrine neoplasms. Uncertainty regarding the efficacy of the available local and systemic treatment strategies is a compounding issue. Even those patients with locally limited disease have a relatively short life expectancy. In this report, we describe a case of deep rectal mixed adenoneuroendocrine carcinoma with long survival after chemoradiation.

CASE PRESENTATION

A 48-year-old Caucasian woman was diagnosed with a grade 3 rectal adenocarcinoma combined with a poorly differentiated large cell neuroendocrine carcinoma component and synchronous metastases (cT3cN1cM1) in both lobes of the liver in 2012. She received concomitant chemoradiotherapy followed by four additional cycles of cisplatin plus irinotecan. Initial treatment induced complete remission of the rectal tumor and liver metastases. Consequently, it was not necessary to surgically resect the primary tumor or any of the metastases. Three months after the end of treatment, one metastasis in the first segment of the liver showed regrowth, and stereotactic body radiotherapy of the metastasis and chemotherapy resulted in a clinical complete response. The patient has been recurrence-free for more than 5 years.

CONCLUSIONS

Extended long-term control of a poorly differentiated metastatic (stage IV) mixed adenoneuroendocrine carcinoma is rare. The multimodal first- and second-line regimens of radiotherapy and chemotherapy described in this case report represent a new therapeutic approach. Encouraged by the results in this case, we compiled a review of the literature on mixed adenoneuroendocrine carcinoma.

Enhanced recovery after surgery in emergency colorectal surgery: Review of literature and current practices

Enhanced recovery after surgery (ERAS), a multidisciplinary program designed to minimize stress response to surgery and promote the recovery of organ function, has become a standard of perioperative care for elective colorectal surgery. In an elective setting, ERAS program has consistently been shown to decrease postoperative complication, reduce length of hospital stay, shorten convalescence, and lower healthcare cost. Recently, there is emerging evidence that ERAS program can be safely and effectively applied to patients with emergency colorectal conditions such as acute colonic obstruction and intraabdominal infection. This review comprehensively covers the concept and application of ERAS program for emergency colorectal surgery. The outcomes of ERAS program for this emergency surgery are summarized as follows: (1) The ERAS program was associated with a lower rate of overall complication and shorter length of hospital stay - without increased risks of readmission, reoperation and death after emergency colorectal surgery; and (2) Compliance with an ERAS program in emergency setting appeared to be lower than that in an elective basis. Moreover, scientific evidence of each ERAS item used in emergency colorectal operation is shown. Perspectives of ERAS pathway in emergency colorectal surgery are addressed. Finally, evidence-based ERAS protocol for emergency colorectal surgery is presented.

[Prognostic analysis of colon and rectal neuroendocrine neoplasm in different stages]

Objective: To explore the survival difference of patients with colon and rectal neuroendocrine neoplasm (NEN) at different stages. Methods: We identified 8 679 patients with colorectal NEN diagnosed between 1988 and 2014 from the Surveillance, Epidemiology, and End Results (SEER) registry, including 5 437 rectal NEN and 3 242 colon NEN ( 1 681 cecum NEN ). Survival curve was drawn by Kaplan-Meier method. Prognostic factors were analyzed by univariate analysis and multivariate Cox regression model. Results: The ratio of male patients with colon and rectal NEN was similar to female (P=0.095). Rectal NEN patients were younger (P<0.001), more highly differentiated (P<0.001), and with earlier stage (P<0.001). Survival analysis showed that the survival of rectal NEN was superior to that of colon NEN, with 10-year tumor-specific survival rates of 86.8% and 44.8% respectively (P<0.001). Multivariate Cox analysis showed that age, gender, marital status, primary tumor site, grade, stage and surgery were independent prognostic factors of colorectal NEN (all P<0.01). The most important factor was stage (HR=3.531), followed by differentiation grade (HR=1.856). Stratified analysis displayed that the survival of rectal NEN in stage Ⅰ, Ⅱ and Ⅳ were better than those of corresponding stage of colon NEN (all P<0.05), but worse in stage Ⅲ (P=0.012). While the survival of rectal NEN were significantly better than those of colon NEN within all stages after excluding 1681 cases of cecal NEN (all P<0.05). Among the patients with well-differentiated NEN, the survival of rectal NEN in stage Ⅰ, Ⅲ and Ⅳ were better than those of corresponding stage of colon NEN (all P<0.05) while there was no significant difference in stage Ⅱ(P=0.169). For poor-differentiated NEN, only the survival of rectal NEN patients in stage Ⅳ (P=0.001) was significant longer than those of colon NEN, while there was no significant difference in stage Ⅰ, Ⅱ and Ⅲ (stage Ⅰ: P=0.760; stage Ⅱ: P=0.181; stage Ⅲ: P=0.313). Conclusions: The survival of NEN patients in colon and rectum is different. Cecum NEN should be considered as a separated tumor for prognostic analysis due to its special clinicopathologic characteristics.

Impact of Length of Distal Margin on Outcomes Following Sphincter Preserving Surgery for Middle and Lower Third Rectal Cancers

Outcomes of sphincter preserving surgery for distal rectal cancers improve with clear circumferential resection and distal resection margin. However, the extent of distal resection margin after a complete mesorectal excision is often a cause for debate. We evaluated the outcome of middle and lower third rectal cancer patients undergoing sphincter preservation with variable distal resection margin at our center. Patients with biopsy-proven rectal adenocarcinoma within 10 cm from anal verge undergoing sphincter preserving resections were included. Patients with positive circumferential resection margin were excluded. Patients were divided into three groups based on the extent of distal resection margin (< 6 mm, 6-10 mm, > 10 mm) and oncological outcomes were compared. The median age of 242 patients was 50 years and 44 (18.2%) were high-grade tumors. Preoperative chemoradiation was used in 185 (75.2%) patients. Median distal resection margin was 20 mm. Patients in < 10 mm group had a significantly higher proportion of lower third (68.3% vs 39.8%, p = 0.004) and chemoradiation-treated tumors (85.4 vs 74.6%, p = 0.001). A significantly higher percentage required an intersphincteric resection in the < 10 mm group (53.7% vs 14.4%, p = 0.0001). Significantly higher percentage tumors were pT3 in > 10 mm group (45.3% vs. 31.7%) (p = 0.05). The median follow-up was 23 months. There was no difference in the overall, loco-regional, and distant recurrence rates between the three groups. A subcentimeter distal resection margin does not influence loco-regional or distant recurrence rates following sphincter preserving surgery for middle and lower third rectal adenocarcinoma.

Colonic Ewing Sarcoma/PNET associated with liver metastases: A systematic review and case report

Ewing Sarcoma is a highly lethal undifferentiated tumor of bone. ES is a small round cell tumor with etiological and characteristic chromosomal translocations between TET/FET (TLS/FUS, EWSR1, and TAF15) and ETS (E26 transformation-specific) family genes. Generally, therapeutic approach for metastatic Ewing Sarcoma includes both local (surgery and radiotherapy) and systemic (chemotherapy) disease control with an overall cure rate of 20%. For extra-osseous tumors, the most common primary sites of disease are trunk, extremities, head and neck, retroperitoneum. Among other sites, Ewing Sarcoma/PNET may also rarely arise in colon and rectum. Even if colonic Ewing Sarcoma/PNET have been previously reported in 5 cases, none of those reports came from right side of the colon. In this article, we report the first case of right-sided Ewing Sarcoma with synchronous liver metastases completely responding to first line chemotherapy. Furthermore, we provide a systematic qualitative review of the current literature on adult colorectal Ewing Sarcoma using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA).

Pseudoaneurysm rupture causing hemoperitoneum following rectal impalement injury: A case report

INTRODUCTION

Although vascular anatomy of the rectum is complex, pseudoaneurysm followed by massive hemoperitoneum after rectal impalement injury is extremely rare.

CASE PRESENTATION

A 43-year-old man presented with abdominal distension. One day earlier, he had undergone sigmoid loop colostomy for rectal implement injury at a local hospital. After the operation, he had become hemodynamically unstable. Digital rectal examination showed a penny-sized anterior rectal wall defect 6 cm from the anal verge. Computed tomography (CT) revealed a hematoma (12 × 10 × 15 cm) with bleeding in the pelvic cavity and an adjacent pseudoaneurysm in the rectum. A large amount of blood and massive hematoma were evacuated by surgery. The Hartmann procedure was performed, but the pseudoaneurysm was not resected. On the 11th postoperative day, hemoglobin decreased (11.6 g/dL-7.9 g/dL), and CT revealed a recurrent hematoma (6.0 × 4.2 cm) in the pelvic cavity, with a residual pseudoaneurysm. Angiography failed to localize the pseudoaneurysm. Consequently, prophylactic embolization at the anterior branch of both the internal iliac arteries was performed. The subsequent hospitalization course was uneventful.

DISCUSSION

Rectal impalement injury may result in pseudoaneurysm of the rectal arteries. However, pseudoaneurysm rupture of the mid rectal artery, followed by massive hemoperitoneum, has not been reported in the English literature. From our experience, preoperative diagnosis of a pseudoaneurysm is crucial for definite surgical management. When surgical resection is indicated, it should include the underlying pseudoaneurysm.

CONCLUSION

Although pseudoaneurysm rupture causing hemoperitoneum after a rectal impalement injury is extremely rare, meticulous preoperative evaluation is necessary for correct management.

Residual mesorectum on postoperative magnetic resonance imaging following transanal total mesorectal excision (TaTME) and laparoscopic total mesorectal excision (LapTME) in rectal cancer

BACKGROUND

The standard treatment for mid- and low-rectal cancer is total mesorectal excision. Incomplete excision is an important predictor of local recurrence after rectal cancer surgery. Transanal TME (TaTME) is a new treatment option in which the rectum is approached with both laparoscopic and transanal endoscopic techniques. The aim of the present study was to determine the prevalence and localisation of residual mesorectal tissue by postoperative magnetic resonance imaging (MRI) of the pelvis and compare this between TaTME and laparoscopic TME (LapTME) patients. In addition, we assessed correspondence with histopathological quality.

METHODS

Two groups of patients with cT1-T3 rectal cancer who underwent TME surgery with primary anastomosis were included, each group consisting of 32 patients. Postoperative T2-weighted MRI of the pelvis was performed at least 6 months after TME surgery and evaluated by two radiologists independently. Residual mesorectum was defined as any residual mesorectal tissue detectable after TME. Localisation of the tissue was categorised in relation to height in the pelvis and position of the level of anastomosis.

RESULTS

Residual mesorectal tissue was detected in 3.1% of TaTME patients and of 46.9% in LapTME patients (p < 0.001). Multivariate analysis identified only type of surgery as a significant risk factor for leaving residual mesorectum. Other known risk factors for incomplete TME, such as body mass index (BMI) and male gender, were not significant. No relation was seen between specimen quality and prevalence of residual mesorectum.

CONCLUSIONS

The completeness of mesorectal excision was significantly better with TaTME than with standard laparoscopic technique.

AGA Institute Clinical Practice Update: Endoscopic Submucosal Dissection in the United States

Endoscopic submucosal dissection (ESD) is an established endoscopic resection method in Asian countries, which is increasingly practiced in Europe and by early adopters in the United States for removal of early cancers and large lesions from the luminal gastrointestinal tract. The intent of this expert review is to provide an update regarding the clinical practice of ESD with a particular focus on its use in the United States. This review is framed around the 16 best practice advice points agreed upon by the authors, which reflect landmark and recent published articles in this field. This expert review also reflects our experience as advanced endoscopists with extensive experience in performing and teaching others to perform ESD in the United States. Best Practice Advice 1: Endoscopic submucosal dissection should be recognized as a mature endoscopic technique that enables complete removal of lesions that are too large for en bloc endoscopic mucosal resection or are at increased risk of containing cancer. Best Practice Advice 2: The safety and feasibility of endoscopic submucosal dissection for early gastric cancer is well established. The absolute indications for curative endoscopic resection include moderately and well-differentiated, nonulcerated, mucosal lesions that are ≤2 cm in size. Best Practice Advice 3: Other relative (expanded) indications for gastric endoscopic submucosal dissection include moderately and well-differentiated superficial cancers that are >2 cm, lesions ≤3 cm with ulceration or that contain early submucosal invasion, and poorly differentiated superficial cancers ≤2 cm in size. The risk of lymph node metastasis when endoscopic submucosal dissection is performed for these indications is higher than when it is performed for absolute indications but remains acceptably low. Best Practice Advice 4: Endoscopic submucosal dissection may be considered in selected patients with Barrett's esophagus with the following features: large or bulky area of nodularity, lesions with a high likelihood of superficial submucosal invasion, recurrent dysplasia, endoscopic mucosal resection specimen showing invasive carcinoma with positive margins, equivocal preprocedural histology, and intramucosal carcinoma. Best Practice Advice 5: Endoscopic submucosal dissection is the primary modality for treatment of squamous cell dysplasia and cancer confined to the superficial esophageal mucosa. Any degree of submucosal invasion caries an increased risk of lymph node metastasis and alternative/additional therapy should be considered. Best Practice Advice 6: Duodenal endoscopic submucosal dissection is associated with an increased risk of intraprocedural perforation and delayed adverse events. Duodenal endoscopic submucosal dissection should be limited to endoscopists with extensive experience in performing endoscopic submucosal dissection in other locations. It is strongly suggested that endoscopists in the United States refrain from performing duodenal endoscopic submucosal dissection during the early phase of their endoscopic submucosal dissection practice. Best Practice Advice 7: All colorectal lesions should be evaluated for suitability for endoscopic resection. Accumulating evidence has shown that the majority of colorectal neoplasms without signs of deep submucosal invasion or advanced cancer can be treated by advanced endoscopic resection techniques. Best Practice Advice 8: Colorectal neoplasms containing dysplasia confined to the mucosa have no risk for lymph node metastasis and endoscopic resection should be considered as the criterion standard. Best Practice Advice 9: Large (>2 cm) colorectal lesions frequently (>43%) require piecemeal removal when endoscopic mucosal resection is used, which is associated with increased (up to 20%) rates of recurrent neoplasia. Endoscopic submucosal dissection enables higher rates of en bloc resection and lower recurrence rates for these lesions. Patients with large complex colorectal polyps should be referred to a high-volume, specialized center for endoscopic removal by endoscopic mucosal resection or endoscopic submucosal dissection. Best Practice Advice 10: Endoscopic resection for colorectal lesions offers significant cost benefit compared with surgery, and case-based endoscopic submucosal dissection selection for high-risk lesions could offer cost savings. Best Practice Advice 11: Endoscopists in the United States embarking on performing endoscopic submucosal dissection should be familiar with currently available endoscopic tissue closure devices. Both clip closure and endoscopic suturing techniques have been shown to be effective in managing intraprocedural perforation. Complete closure of a post-endoscopic submucosal dissection site may be considered in certain circumstances based on patient factors, procedural factors, and the location of the lesion. Best Practice Advice 12: Careful coagulation of exposed blood vessels in the resection site may reduce the risk of delayed bleeding after endoscopic submucosal dissection. The use of low-voltage coagulation current is recommended for this technique. Best Practice Advice 13: Endoscopists should affix the endoscopic submucosal dissection specimen to a flat surface (eg, pin the specimen to cork board) and immerse it in formalin. An expert gastrointestinal pathologist should evaluate the specimen for margin involvement, degree of differentiation, presence or absence of lymphovascular invasion, depth of submucosal invasion (if present), and tumor budding. Best Practice Advice 14: Acquiring high-level competency in endoscopic submucosal dissection is achievable in the United States. Alternative educational models should be used in the United States because of the limited number of experts and the differing prevalence of gastrointestinal luminal diseases as compared with Asia. Best Practice Advice 15: The endoscopic submucosal dissection educational model most suited for the current environment in the United States is a stepwise approach consisting of didactic self-study, attending training courses with increasing levels of complexity, self-practice on animal models, and observation of live cases performed by experts. Endoscopists should perform their initial endoscopic submucosal dissections on patients with lesions that have well-established indications for endoscopic submucosal dissection and are of the lowest technical complexity. Best Practice Advice 16: Endoscopists in the United States who perform endoluminal resection should educate referring physicians to avoid practices that may induce submucosal fibrosis hampering future endoscopic mucosal resection or endoscopic submucosal dissection. These practices include tattooing in close proximity to or beneath a lesion for marking and partial snare resection of a portion of a lesion for histopathology.

[The evaluation of stored feces in elderly patients by ultrasonography: Three case studies]

Providing defecation care can be challenging because bowel movements cannot be directly observed in home-care settings, and the objective evaluation of constipation symptoms is difficult, particularly for elderly patients with cognitive impairment. We evaluated the use of rectal ultrasonography (US) to assess the properties and volume of feces in three cases with different fecal properties. Case 1: In a 94-year-old man with normal feces (Bristol stool score: BS type 4), rectal US revealed a crescent-shaped high-echo area without acoustic shadow that was present until the next defecation. Case 2: In a 92-year-old woman with hard stool (BS type 1), rectal US showed a crescent-shaped strong-echo area with acoustic shadow that was present until the next defecation. The length of the high-echo area gradually increased during the observation period and decreased after defecation in Cases 1 and 2. Case 3: In a 67-year-old man with watery stool (BS type 7), rectal US revealed a low-peripheral-frequency-echo area without acoustic shadow. Rectal ultrasonography was able to demonstrate the presence or absence of hard stool, which was observed as a crescent-shaped a strong, high-echo area with acoustic shadow; the presence or absence of hard stool may be evaluated based on these findings. Furthermore, the fecal volume may be able to be evaluated based on the long diameter of the crescent-shaped high-echo area. Determining the best course of defecation care based on the fecal properties/volume evaluated using rectal US will likely be possible in the future.

[Retrorectal stromal tumor: macroscopic entity and surgical difficulties]

Gastrointestinal stromal tumors are uncommon mesenchymal tumors that very rarely occur in the rectum. They pose preoperative diagnostic and therapeutic problems. We report the case of retrorectal stromal tumor in order to highlight the clinical, radiological and therapeutic features of this rare entity.

Computed tomography and magnetic resonance imaging findings of metastatic rectal linitis plastica from prostate cancer: A case report and review of literature

Linitis plastica is a rare condition showing circumferentially infiltrating intramural anaplastic carcinoma in a hollow viscus, resulting in a tissue thickening of the involved organ as constricted, inelastic, and rigid. While most secondary rectal linitis plastica (RLP) is caused by metastasis from stomach, breast, gallbladder, or bladder cancer, we report an extremely rare and unique case of secondary RLP due to prostate cancer with computed tomography (CT) and magnetic resonance imaging (MRI) findings, including diffusion weighted imaging (DWI). A 78-year-old man presented with approximately a 2-mo history of constipation and without cancer history. On sigmoidoscopy, there was a luminal narrowing and thickening of rectum with mucosa being grossly normal in its appearance. On contrast-enhanced CT, marked contrast enhancement with wall thickening of rectum was noted. On pelvic MRI, rectal wall thickening showed a target sign on both T2-weighted imaging and DWI. A diffuse infiltrative lesion was suspected in the prostate gland based on low signal intensity on T2-weighted imaging and restricted diffusion. A transanal full-thickness excisional biopsy revealed metastasis from a prostate adenocarcinoma invading the submucosa to the muscularis propria consistent with metastatic RLP. We would like to emphasize the CT and MRI findings of metastatic RLP due to prostate cancer.

The relation of fetal colon and rectum diameters with labor in healthy late-third trimester pregnancies

OBJECTIVE

To investigate the associations of fetal colon-rectum diameters with labor and fetal distress or meconium passage in healthy pregnancies in the late 3rd trimester.

STUDY DESIGN

A total of 162 healthy, singleton pregnant women at ≥36^0/7 weeks who were in the latent-phase of labor (n = 69) or those not in labor (n = 93, controls) at the time of ultrasound examination were enrolled. Fetal colon (ascending, transverse, descending, sigmoid) and rectum diameters, Doppler indices of materno-fetal vessels were measured. Data were analyzed according to the mode of delivery.

RESULTS

Fetal colon-rectum diameters were smaller in women in labor compared to controls (p = 0.001). Positive correlations were observed between fetal colon-rectum diameters and interval between ultrasound and labor onset in the control group except for those who had scheduled cesarean sections (C/S) (p = 0.001). Similar colon-rectum measurements were obtained in fetuses delivered via cesarean section due to fetal distress or to other indications (p > 0.05). In women who had uterine contractions during ultrasound examination; later delivered by vaginal route, no association was observed between Apgar scores and colon-rectum diameters during latent-phase (p > 0.05), and also there were significant positive correlations between different segments of colon-rectum diameters and duration of neonatal meconium passage (p < 0.05).

CONCLUSION

Fetal colon and rectum diameters are smaller during labor and the measurements tend to diminish as the labor approaches, but do not indicate fetal distress.