Anatomy of the lateral ligaments of the rectum: A controversial point of view

The existence and composition of the lateral ligaments of the rectum (LLR) are still the subjects of anatomical confusion and surgical misconception up to now. Since Miles proposed abdominoperineal excision as radical surgery for rectal cancer, the identification by "hooking them on the finger" has been accepted by many surgeons with no doubt; clamping, dividing and ligating are considered to be essential procedures in mobilization of the rectum in many surgical textbooks. But in cadaveric studies, many anatomists could not find LLR described by the textbooks, and more and more surgeons also failed to find LLR during the proctectomy according to the principle of total mesorectal excision. The anatomy of LLR has diverse descriptions in literatures. According to our clinical observations, the traditional anatomical structures of LLR do exist; LLR are constant dense connective bundles which are located in either lateral side of the lower part of the rectum, run between rectal visceral fascia and pelvic parietal fascia above the levator ani, and covered by superior fascia of pelvic diaphragm. They are pathways of blood vessels and nerve fibers toward the rectum and lymphatic vessels from the lower rectum toward the iliac lymph nodes.

Diffuse hemolymphangioma of the rectum: A report of a rare case

Intestinal hemolymphangioma is a rare vascular and lymphatic malformation and is manifested as anaemia and recurrent alimentary tract hemorrhage. Few cases of hemolymphangioma occurring in small intestine, spleen, esophagus and other organs have been reported. We herein report a case of a 37-year-old man with severe rectal bleeding. Digital examination revealed nodular mucosa. No rectal mass was palpated, but bleeding in the ampulla was detected. Colonoscopy revealed an extensive hypervascular submucosal lesion arising from the rectosigmoid junction colon to the distal edge of the anus. Endoscopic ultrasonography demonstrated an extensive anechoic mass with clear edge. Magnetic resonance imaging (MRI) showed a significant thickness of the rectal wall, extending to the distal edge of the anus, with a narrowing lumen. A sphinctersaving rectal surgery was performed. Due to a lack of knowledge of the clinical, endoscopic and radiological features, preoperative recognition of hemolymphangioma is not easy. Computed tomography and MRI are helpful in confirming the diagnosis, and defining the extent and invasion of the lesion. For the low malignant potential tumors, a sphincter-saving rectal surgery is recommended after a full evaluation of the tumor.

RELATIONSHIP BETWEEN INTERNAL ANAL SPHINCTER FUNCTION AND LENGTH OF REMAINING RECTUM AFTER RESECTING RECTAL CARCINOMA

Objective: To study the relationship between internal anal sphincter function and length of remaining rectum after resecting rectal carcinoma. Methods: Preoperatively, 21 patients were evaluated via patients' clinical date, including anal resting pressure (resting pressure) assay. Six months postoperatively, repeated manometric studies and clinical evaluations were performed to assess the level of continence . The formula use for calculating post operative resting pressure is as follows: postoperative resting pressure=0.42×preoperative resting pressure+1.56×length of remaining recturm+12.37(R 2=0.58; P <0.01).Degree of continence was graded based on severity of the dysfunction and grade of the continence score. Results: It was demonstrated the patients with low postoperative resting pressures (<4.0 Kpa) had incontinence, and those with high postoperative resting pressures (>4.7 Kpa) were continent. There were significant correlations between length of the remaining rectum and ratio of the decrease in maximum resting pressure (postoperative/preoperative maximum resting pressure;r=0.62; P <0.01). Conclusion: Continence of rectum is influenced by maximum resting pressure of function of the internal anal sphincter, length of remaining rectum is shorter, the more damage to the internal anal sphincter. It is able to foretell stool incontinence by using the postoperative resting pressure formula, and to determine the length of the remaining rectum.

Large heterotopic gastric mucosa and a concomitant diverticulum in the rectum:Clinical experience and endoscopic management

Heterotopic gastric mucosa(HGM) in the rectum is an extremely rare clinical entity which may be missed or misdiagnosed due to a lack of knowledge.In the present study,a 14-year-old girl visited our hospital due to a 5-year history of repeated hematochezia.Colonoscopy showed a solitary superficial depressed lesion approximately 5 cm in size and a concomitant 1.5 cm deep diverticulum in the rectum.Histological examination of the endoscopic biopsy showed typical ectopic gastric mucosa in the depressed lesion and inside the diverticulum.Narrow band imaging further confirmed the histological results.Endoscopic ultrasound indicated that the lesion originated from the mucosal layer,and partially involved the submucosal layer.Endoscopic submucosal dissection was performed in this patient due to the large size and shape of the lesion.No bleeding,perforation or other adverse events were observed.The presence of HGM in the diverticular cavity greatly increased the surgical difficulty.A literature review was also carried out in our study.

Schwannoma of the rectum:A case report and literature review

Schwannoma is a tumor originating from the Schwann cells. Gastrointestinal schwannomas are uncommon stromal tumors of the intestinal tract and, in particular, rectal schwannomas are extremely rare. In fact, it is well established that schwannomas appear more frequently in the stomach and in the small intestine, while location in the colon or in the rectum is uncommon. Reading the literature, only few cases of rectal schwannoma have been reported. Their diagnosis is confirmed by the immunohisto chemical panel(S-100 protein). When these tumors are located in the colon and in the rectum, radical excision with wide margins is mandatory, due to their tendency to recur locally or become malignant, if left untreated. In the present study, we describe a case of a rectal schwannoma occured in a 72-year-old man, presented as a small polypoid lesion, which was successfully removed in toto by hot-biopsy, during the same endoscopy, due to the dimensons. No recurrence of the lesion was observed after 6 mo of follow-up.

Melanoma of the rectum: A rare entity

A 41-year-old man presented with a 6-mo history of changed defecation and rectal bleeding. A 3-cm polypoid tumor of the lower rectum was found at rectosigmoidos- copy, which proved to be a leiomyosarcoma upon biopsy. Dissemination studies did not show any metastases. He was underwent to an abdomino-perineal resection (APR). Histopathology of the specimen showed a melanoma (S-100 stain positive). Two years after the resection, me- tastases in the abdomen and right lung were found. He died one and half years later. Primary anorectal melano- ma is a rare and very aggressive disorder. According to current data, one should always perform a S-100 stain when anorectal sarcoma is suspected. A positive S-100 stain suggests the tumour to be most likely a melanoma. Subsequently, thorough dissemination studies need to be performed. Depending on the outcome of the dissemina- tion studies, a surgical resection has to be performed. Nowadays, a sphincter-saving local excision combined with adjuvant loco-regional radiotherapy should be pre- ferred in case of small tumors. The same loco-regional control is achieved with less "loss of function" compared to non-sphincter saving surgery. Only in the case of large and obstructing tumors an abdomino-perineal resection is the treatment of choice.

Dedifferentiated liposarcoma of the rectum:A case report

Liposarcoma is one of the most common soft tissue sarcomas found in adults,and it usually occurs in the retroperitoneum and the extremities.Here,we describe a case of dedifferentiated liposarcoma originating from a well-differentiated liposarcoma of the mesorectum that presented as a protruding mass in the rectal lumen.Hartmann's operation with total mesorectal excision was performed and the tumor was removed radically.No management guidelines are currently available for liposarcoma of the rectum.We propose that complete surgical resection be required for the treatment of rectal liposarcoma and that a long-term detailed follow up is necessary.

Granulocytic sarcoma of the rectum:Report of one case that presented with rectal bleeding

Granulocytic sarcoma is an uncommon and localized extramedullary tumor composed of immature granu-locytic cells.It may present in association with acute myeloid leukaemia,myelodysplastic syndrome and chronic myelogenous leukaemia.Granulocytic sarcoma may occur in any anatomical site but involvement of the gastrointestinal tract is rare,especially in the rectum.We report on the case of a 17 year old female who presented with rectal bleeding,abdominal pain and weight loss one mo prior to admission.Recto-sigmoidoscopy revealed a rectal polypoid and ulcerated mass.The histological examination of the mass showed granulocytic sarcoma.Bone marrow examination was compatible with acute promyelocytic leukaemia(FABtype M3).This case report is a reminder of this peculiar sign of tumoral syndrome in acute myeloid leukaemia.We also discuss diagnostic methods and analyze the disease course.

Malignant paraganglioma of the rectum:The first case report and a review of the literature

Paragangliomas typically develop in the extra-adrenal sites along the sympathetic and/or the parasympathetic chain.Occasionally,the tumors may arise in some exotic sites,including the head and neck region and the urogenital tract.Paraganglioma presenting as a primary rectal neoplasm has not been well described in the literature.Here,we report the first case of malignant paraganglioma arising in the rectum of a 37-year-old male.He presented to the clinic because of hematochezia with tenesmus.The anorectal digital examination and colonoscopic examination revealed a polypoid mass of the rectum,measuring approximately 4 cm in diameter.The overall morphology and immunophenotype were consistent with a typical paraganglioma.However,the tumor exhibited features suggestive of malignant potential,including local extension into adjacent adipose tissue,nuclear pleomorphism,confluent tumor necrosis,vascular invasion and metastases to regional lymph nodes.In conclusion,we present the first case of rectal malignant paraganglioma.Due to the unexpected occurrence in this region,malignant paraganglioma may be misdiagnosed as other tumors with overlapping features;in particular,a neuroendocrine tumor of epithelial origin.Because of the differences in treatment,separating paraganglioma from its mimics is imperative.Combination of morphology with judicious immunohistochemical study is helpful in obtaining the correct diagnosis.

Small-cell neuroendocrine carcinoma of the rectum—a rare tumor type with poor prognosis:A case report and review of literature

BACKGROUND Small-cell neuroendocrine carcinoma(SNEC)of the rectum is a rare tumor associated with poor prognosis.CASE SUMMARY We report a case of a 77-year-old male who came into our hospital because of blood with his stool.An endoscopy revealed a cauliflower-like neoplasm in his rectum.Imaging examination showed that the lesion in the upper rectum was likely rectal cancer,and there was no evidence of metastasis.The patient was treated with surgery.Pathological examination confirmed SNEC of the rectum and an R0 resection was achieved.However,1 mo after the operation,the patient developed intestinal and ureteral obstructions due to peritoneal metastases.Finally,the patient died from renal failure.CONCLUSION SNEC of the rectum is a high-grade carcinoma with an aggressive phenotype,and surgery should be cautiously considered.

Endoscopic submucosal dissection for small submucosal tumors of the rectum compared with endoscopic submucosal resection with a ligation device

AIMTo evaluate the efficacy and safety of endoscopic submucosal dissection (ESD) for small rectal submucosal tumors (SMTs). METHODSBetween August 2008 and March 2016, 39 patients were treated with endoscopic submucosal resection with a ligation device (ESMR-L) (n = 21) or ESD (n = 18) for small rectal SMTs in this study. Twenty-five lesions were confirmed by histological evaluation of endoscopic biopsy prior to the procedure, and 14 lesions were not evaluated by endoscopic biopsy. The results for the ESMR-L group and the ESD group were retrospectively compared, including baseline characteristics and therapeutic outcomes. RESULTSThe rate of en bloc resection was 100% in both groups. Although the rate of complete endoscopic resection was higher in the ESD group than in the ESMR-L group (100% vs 95.2%), there were no significant differences between the two groups (P = 0.462). In one patient in the ESMR-L group with a previously biopsied tumor, histological complete resection with a vertical margin involvement of carcinoid tumor could not be achieved, whereas there was no incomplete resection in the ESD group. The mean length of the procedure was significantly greater in the ESD group than in the ESMR-L group (14.7 ± 6.4 min vs 5.4 ± 1.7 min, P vs 2.8 ± 1.5 d, P CONCLUSIONBoth ESMR-L and ESD were effective for treatment of small rectal SMTs. ESMR-L was simpler to perform than ESD and took less time.

Collision tumor of the rectum: A case report of metastatic gastric adenocarcinoma plus primary rectal adenocarcinoma

Collision tumors are thought to arise from the accidental meeting and interpenetration of two independent tumors. We report here a highly unusual case of a 61-year old man who had a unique tumor that was composed of a metastatic adenocarcinoma from the stomach to the rectum, which harbored a collision tumor of primary rectal adenocarcinoma. The clonalities of the two histologically distinct lesions of the rectal mass were confirmed by immunohistochemical and molecular analysis. Although histologic examination is the cornerstone in pathology, immunohistochemical and molecular analysis can provide evidence regarding whether tumors originate from the same clone or different clones. To the best of our knowledge, this is the fi rst reported case of such an occurrence.

Gastrointestinal Stromal Tumors in the Rectum

OBJECTIVE To investigate the clinical and pathologic features of rectal gastrointestinal stromal tumors （GIST） and to evaluate their reasonable management. METHODS The clinical and pathological data for 19 patients with rectal GIST over the past 19 years were studied retrospectively. RESULTS The diagnosis of the 19 cases was identified by surgery and pathology. All the rectal GISTs were spindle cell type with immunohistochemical analysis showing positive reactivity for CD117 （100%） and CD34 （73.7%）. There were 4 cases of high risk, 3 cases of intermediate risk, 5 cases of low risk and 7 cases of very low risk of aggressive behavior in this study. CONCLUSION Rectal GIST, without specific symptoms in the early stage, has a low incidence and usually shows low risk of aggressive behavior. It is difficult to produce an accurate pathological diagnosis before operation and it is difficult to decide whether to save the sphincter before or during operation. Reasonable initial treatment includes trans-anal local resection as the best recommend management of low risk submucosal rectal GIST （〈3.0 cm）.

Cancer-like foreign-body in rectum wall:A case report

Foreign bodies in the rectum wall,whose most common causes are aberrant sexual activity and intake of small fishbone fragments by mistake,usually have a clear history,presenting an acute upset.However,chronic presence of a foreign-body can result in inflammatory reaction and stromal proliferation,and can even accelerate the occurrence and deterioration of tumors through different mechanisms,such as reactive oxygen species.Foreign bodies in the rectum wall may induce complications and lead to misdiagnosis.Colonoscopy and biopsy pathology are one of the most trusted techniques for diagnosis.

Cortical and spinal evoked potential response to electrical stimulation in human rectum

AIM: To study a novel technique to record spinal and cortical evoked potentials (EPs) simultaneously in response to electrical stimulation in the human rectum. METHODS: Eight male and nine female healthy volunteers participated. Stimulating electrodes were attached to the rectal mucosa at 15 cm and 12 cm above the dentate line. Recording skin electrodes were positioned over vertebrae L4 through S2. The electrical stimulus was a square wave of 0.2 ms duration and the intensity of the stimulus varied between 0 and 100 mA. EP responses were recorded using a Nicolet Viking IV programmable signal conditioner.RESULTS: Simultaneous recording of cortical and spinal EPs was obtained in > 80% of the trials. The EP responses increased with the intensity of the electrical stimulation, were reproducible overtime, and were blocked by application of Lidocaine jelly at the site of stimulation. The morphology (N1/P1), mean ± SD for latency (spinal N1, 4.6 ± 0.4 ms; P1, 6.8 ± 0.5 ms; cortical N1, 136.1 ± 4.2 ms; P1, 233.6 ± 12.8 ms) and amplitude (N1/P1, spinal, 38 ± 7 μV; cortical 19 ± 3 μV) data for the EP responses were consistent with those in the published literature. Reliable and reproducible EP recordings were obtained with the attachment of the electrodes to the rectal mucosa at predetermined locations between 16 and 8 cm above the anal verge, and the distance between the attachment sites of the electrodes (the optimal distance being approximately 3.0 cm between the two electrodes). CONCLUSION: This technique can be used to assess potential abnormalities in primary afferent neural pathways innervating the rectum in several neurodegenerative and functional pain disorders.

Can the Rectum Balloon Minimize Rectal Toxicity During Irradiation Therapy of Prostate Cancer?

The irradiation of the rectum cancer occurs in many institutes by using a rectum balloon in order to reduce the mobility of the target organ and to distance the rectum from the target organ. The objective is to reduce side effects quantitatively as well as qualitatively. On the basis of two hospitals using identical techniques for the prostate irradiation with the sole difference of the rectum balloon the toxicity has been evaluated with the result of no significant difference between the cohorts concerning diarrhea, rectal pain symptoms and rectal bleedings. Therefore the authors consider the use of the rectum balloon prior to each irradiation not necessary for the reduction of toxicity particularly due to the fact that the application is often very painful, especially for patients with hemorrhoids. The rectum balloon as a tool for the reduction of the prostate mobility was not objective of this study.

Neoadjuvant Radiotherapy in Stage I Cancer of the Lower Rectum

Introduction: The mortality rate in cancer of the lower rectum is related to the incidence of local recurrence, in the first 5 years. For stage I tumors, local excision has being increasingly used, but recent studies showed a higher incidence rate of local recurrence. Therefore, preoperative radiotherapy should be considered even for these tumors, as an attempt to prevent recurrence and provide cure. Objective: To show the effectiveness of neoadjuvant radiotherapy in stage I cancer of the lower rectum of a cohort population. Materials and Method: A cohort study in a prospective database was made with a total of 75 patients considered as stage I cancer of the lower rectum. Preoperative long course of 4500 cG radiotherapy was performed in this selected group of patients and followed up for a minimum period of five years. Results: Stage I/TI group had 27 patients. All of them presented complete response to the treatment and did not need to be submitted to surgery. Five years follow up with no recurrence. The stage I/TII group had 48 patients. After neoadjuvant radiotherapy, 8 patients had to be submitted to surgery for persistent tumor. All were submitted to full total local excision (FTLE), but anatomopathological examination showed no residual cancer. Conclusion: Preoperative long course of 4500 cG irradiation, not only reduced the local recurrence and mortality rate in lower rectal cancer, but also reduced indication for surgery in patients with stage I cancer of the lower rectum.

Potential roles of the rectum keystone microbiota in modulating the microbial community and growth performance in goat model

Background Ruminal microbiota in early life plays critical roles in the life-time health and productivity of ruminant animals.However,understanding of the relationship between gut microbiota and ruminant phenotypes is very limited.Here,the relationship between the rectum microbiota,their primary metabolites,and growth rate of a total of 76 young dairy goats(6-month-old)were analyzed,and then 10 goats with the highest or lowest growth rates respectively were further compared for the differences in the rectum microbiota,metabolites,and animal’s immune parameters,to investigate the potential mechanisms by which the rectum microbiota contributes to the health and growth rate.Results The analysis of Spearman correlation and microbial co-occurrence network indicated that some keystone rectum microbiota,including unclassified Prevotellaceae,Faecalibacterium and Succinivibrio,were the key modulators to shape the rectum microbiota and closely correlated with the rectum SCFA production and serum IgG,which contribute to the health and growth rate of young goats.In addition,random forest machine learning analysis suggested that six bacterial taxa in feces could be used as potential biomarkers for differentiating high or low growth rate goats,with 98.3%accuracy of prediction.Moreover,the rectum microbiota played more important roles in gut fermentation in early life(6-month-old)than in adulthood stage(19-month-old)of goats.Conclusion We concluded that the rectum microbiota was associated with the health and growth rate of young goats,and can be a focus on the design of the early-life gut microbial intervention.

ACUPUNCTURE TREATMENT FOR PROLAPSE OF THE RECTUM

Prolapse of the rectum refers to theprolapse or evagination of the anal canal,rectum or even the sigmoid colon outsidethe anus. It often occurs in children, the el-derly of weak constitution or multiparouswomen. Colitis, dysentery, long--termcoughing, constipation, vesical calculus andstrenuous physical labour are remote

Collision carcinoma of the rectum involving neuroendocrine carcinoma and adenocarcinoma:A case report

BACKGROUND Collision carcinoma is a rare histological pattern,and includes two or more different types of tumors coexisting in the same organ as one neoplasm.Different to the combined type,the two adjacent tumors of collision carcinoma are histologically distinct.Collision carcinoma may occur from any origin or organ,including the cecum,liver,cervix,thyroid,stomach,kidney,and esophagus.In the rectum,adenocarcinoma is the most common pathological type,the combined type is rare,and collision tumors are even rarer.To date,only a limited number of collision carcinoma cases originating from the rectum have been reported.Due to the scarcity of rectal collision carcinoma,more cases need to be reported to fully understand the clinico-pathological features and biological behavior of the tumor.CASE SUMMARY Here we report a 40-year-old female who presented with the chief complaints of persistent changes in bowel habits and hematochezia for 10 d.She underwent Miles'operation which revealed a collision carcinoma of the rectum,showing a“side by side”pattern,composed of a high grade neuroendocrine carcinoma,(small cell carcinoma)and moderately differentiated adenocarcinoma,based on its clinico-pathological features and biological behavior.The patient remained disease-free at 12 mo follow-up.We also focused on the related literature and expert opinion.CONCLUSION Collision carcinoma is a rare tumor with ambiguous biological behavior.Greater attention should be paid to its clinico-pathologic diagnosis.Regular and adequate follow-up is essential to help rule out metastasis and assess the prognosis.