Malignant Rectal Tumors Research Articles

Endoscopic Ultrasonography of Malignant Rectal Tumors for the Decision-Making of Therapeutic Action

Endoscopic Ultrasonography of Malignant Rectal Tumors for the Decision-Making of Therapeutic Action

Differentiation between malignant and benign rectal tumors by dual-energy computed tomography - a feasibility study

Introduction: To assess the performance of Dual Energy Computed Tomography (DECT) in the differentiation between benign and malignant tumors in the rectum.Material and methods: We enrolled 8 subjects with rectal tumors suspected to be an early rectal cancer during colonoscopy. All subjects underwent Computed Tomography (CT), Magnetic Resonance Imaging (MRI) and Endorectal Ultrasound (ERUS) for staging. Furthermore, all subjects underwent fast switching of tube voltage between 80 and 140 kVp DECT of the pelvis. The 8 subjects had histopathological verified benign adenomas after transanal endoscopic microsurgery resection (TEM). The 8 subjects were matched with 8 consecutively selected subjects with histopathologically verified malignant rectal tumors. The DECT images were analyzed to assess the difference between malignant and benign rectal tumors. All DECT images were reviewed by experienced radiologists. In each DECT scanning, we applied three regions of interest (ROIs) for the acquisition of the DECT unique quantitative parameters. The mean atomic mass (effective Z value), iodine concentration, dual energy ratio (DER) and dual-energy index (DEI) was determined in both groups.Results: The comparison of the 2 groups showed a significant difference in effective Z and a nonsignificant difference regarding iodine concentration, DER, and DEI in the two groups.Conclusion: Dual-energy CT demonstrated a difference in the mean atomic mass in benign colorectal tumors in comparison to malignant colorectal tumors.

Radiologic Evaluation of Clinically Benign Rectal Neoplasms May Not Be Necessary Before Local Excision

Local excision may be curative for benign and malignant rectal neoplasms. Because many early rectal cancers are discovered incidentally after local excision of clinically benign lesions, it is unclear whether preoperative imaging with transrectal ultrasound or MRI affects management. The purpose of this study was to determine the diagnostic characteristics and effect of preoperative imaging on the incidence of malignancy in benign rectal lesions undergoing local excision. Prospective data from 2 institutions were included. Coarsened exact matching created a balanced cohort comparing imaging and no-imaging groups. The study was conducted at high-volume specialist referral hospitals. Adult patients undergoing local excision via transanal endoscopic surgery between 1997 and 2016 for clinically benign rectal neoplasms were included. The study intervention included preoperative imaging with transrectal ultrasound and/or MRI. We measured the incidence of malignancy and diagnostic accuracy of preoperative imaging. A total of 620 patients were included (272 with preoperative imaging and 348 without). There were 250 patients undergoing transrectal ultrasound, and 24 patients undergoing MRI (2 patients underwent both). Transrectal ultrasound and MRI correctly identified malignant polyps in 50% (11/22) and 44% (8/18). Overall agreement for benign versus malignant polyps between preoperative imaging and final pathology was κ = 0.30 (95% CI, 0.18-0.41) for transrectal ultrasound and 0.29 (95% CI, 0.01-0.57) for MRI. In both the overall and unmatched cohorts, the incidence of malignancy, margin involvement, and proportion of patients requiring salvage surgery was similar. Data were obtained from 2 institutions with different equipment over a long time period. Preoperative imaging did not accurately identify malignancy in clinically benign rectal lesions and did not affect the incidence of malignancy, margin involvement, or proportion of patients requiring salvage surgery. Therefore, preoperative imaging may not be necessary for clinically benign lesions undergoing local excision. See Video Abstract at http://links.lww.com/DCR/A695.

Current state of transanal minimally invasive surgery in the management of rectal cancer

Rectal cancer surgery has undergone a rapid change over the last few decades. We have come a long way from abdominoperineal resection to minimally invasive sphincter preserving techniques. Colorectal cancer screening programs made it possible to diagnose patients at earlier stages and this has led to question the necessity of radical surgery and the possibility of organ preservation. The platform most recently added to the surgical armamentarium is transanal minimally invasive surgery (TAMIS). It utilizes conventional laparoscopic tools to perform endoluminal surgery in rectum. Along with the conceptual changes in rectal cancer management, TAMIS is more frequently used for local excision of malignant rectal tumors. This review highlights the recent advances and current state of the role of TAMIS in the management of rectal cancer at various stages.

Management of a case of high-risk gastrointestinal stromal tumor in rectum by transanal minimal invasive surgery

BackgroundRectal gastrointestinal stromal tumor (GIST) is a very rare tumor of gastrointestinal tract. Surgical management of rectal GIST requires special attention for preserving of anal and urinary functions. Transanal minimal invasive surgery (TAMIS) is a well-developed minimally invasive technique for local excision of benign and early malignant rectal tumors; however, the application of TAMIS for rectal GIST is rarely and inadequately reported. We report the novel application of TAMIS for rectal GIST with considerations for anal and urinary functions.Case presentationA 67 years old female, who presented with history of per rectal bleeding, was diagnosed with submucosal GIST of 4.5 cm in diameter at right posterior wall of 7 cm from anal verge. Histology of biopsy showed abundant spindle-shaped cells arranged in bundles that were positive for CD34 and negative for C-Kit, desmin, smooth muscle actin (SMA), and S-100. The tumor was excised by TAMIS successfully. Final histopathology showed pT2 tumor with C-Kit positive and mitosis count 10 per 50 HPF. Postoperative period was uneventful, and she was discharged on adjuvant imatinib mesylate for 3 years.ConclusionTAMIS can be used safely in the management of rectal GIST after appropriate evaluation of tumor size, extent, location, and experience of operating surgeon.

Assessment of using 360° endorectal ultrasound and real-time elastography in the diagnosis of benign and malignant rectal neoplasms in elderly patients

Objective To evaluate the value of endorectal ultrasonography (ERUS) combined with real-time elastography in the diagnosis of benign and malignant rectal neoplasms in elderly patients. Methods Fifty-six consecutive patients with rectal neoplasms underwent ERUS and real-time tissue elastography at Beijing Hospital from February 2016 to December 2016.The imaging results were compared with results from postoperative or colonoscopic findings. Results Histopathological examinations identified 50 cases of adenocarcinomas, 5 cases of adenomas and 1 case of neurilemmoma.The accuracy, sensitivity and specificity of ERUS in the diagnosis of benign and malignant rectal neoplasms were 89.3% (50/56), 92.0% (46/50), and 66.7% (4/6), respectively.The accuracy, sensitivity and specificity of real-time elastography in the diagnosis of benign and malignant rectal neoplasms were 80.4% (45/56), 82.0% (41/50), and 66.7%(4/6), respectively.However, there was no significant difference in sensitivity and specificity (χ2=3.20 and 0.50, P=0.074 and 0.480) between the two approaches.With the combination of ERUS and real-time elastography in the diagnosis of benign and malignant rectal neoplasms, the sensitivity and specificity were 75.4% and 98.6% for the series method and 88.9% and 44.5% for the parallel method. Conclusions Although elastography may not improve the accuracy of the diagnosis of benign and malignant rectal neoplasms, the strain information it provides can be used as a basis for subsequent diagnosis and treatment decisions. Key words: Rectal neoplasms; Elasticity imaging techniques; Ultrasonography

Promoter methylation and expression of DNA repair genes MGMT and ERCC1 in tissue and blood of rectal cancer patients

Rectal cancer involves one-third of colorectal cancers (CRCs). Recently, data supported that DNA methylation have a role in CRC pathogenesis. In the present study we aimed to analyze the methylation status of MGMT and ERCC1 promoter regions in blood and tissue of patients with benign and malignant rectal tumors. We also studied the methylated MGMT and ERCC1 genes and their relations with clinicopathological features. Furthermore, we suggested that methylation may play a critical function in the regulation of MGMT and ERCC1 expression.Fifty patients with non-metastatic cancer rectum and 43 patients with benign rectal lesions were involved in the study. DNA extraction from blood and rectal specimens was done to analyze the methylation status of MGMT and ERCC1 genes by methylation-specific PCR method. RNA was extracted also to determine the expression levels of these genes by real time-PCR.The frequency of MGMT and ERCC1 methylation was significantly higher in rectum cancers than in benign tumors both for the tissue and the blood (p<0.001). There was no relation between MGMT or ERCC1 methylation and clinicopathological features; while they were correlated with the response to therapy. An interesting finding that the agreement of the methylation levels in the blood and rectal tissue was classified as good (κ=0.78) for MGMT gene and as very good (κ=0.85) for ERCC1. Lastly, the MGMT and ERCC1 genes methylation was associated with down-regulation of their mRNA expression when compared with the non-methylated status.Our findings provided evidence that both blood and tumor tissue MGMT and ERCC1 methylation were associated with cancer rectum. MGMT or ERCC1 methylation in blood could be suitable non-invasive biomarkers differentiating benign and malignant rectal tumors. Furthermore, the methylation of the MGMT and ERCC1 promoter regions was associated with down-regulation of their mRNA expression.

Transanal Endoscopic Microsurgery for Patients With Rectal Tumors: A Single Institution's Experience.

PurposeThe purpose of this study was to look at our complication rates and recurrence rates, as well as the need for further radical surgery, in treating patients with benign and early malignant rectal tumors by using transanal endoscopic microsurgery (TEM).MethodsOur study included 130 patients who had undergone TEM for rectal adenomas and early rectal cancer from December 2009 to December 2015 at the Department of Surgical Oncology, National Cancer Institute, Lithuania. Patients underwent digital and endoscopic evaluation with multiple biopsies. For preoperative staging, pelvic magnetic resonance imaging or endorectal ultrasound was performed. We recorded the demographics, operative details, final pathologies, postoperative lengths of hospital stay, postoperative complications, and recurrences.ResultsThe average tumor size was 2.8 ± 1.5 cm (range, 0.5–8.3 cm). 102 benign (78.5%) and 28 malignant tumors (21.5%) were removed. Of the latter, 23 (82.1%) were pT1 cancers and 5 (17.9%) pT2 cancers. Of the 5 patients with pT2 cancer, 2 underwent adjuvant chemoradiotherapy, 1 underwent an abdominoperineal resection, 1 refused further treatment and 1 was lost to follow up. No intraoperative complications occurred. In 7 patients (5.4%), postoperative complications were observed: urinary retention (4 patients, 3.1%), postoperative hemorrhage (2 patients, 1.5%), and wound dehiscence (1 patient, 0.8%). All complications were treated conservatively. The mean postoperative hospital stay was 2.3 days.ConclusionTEM in our experience demonstrated low complication and recurrence rates. This technique is recommended for treating patients with a rectal adenoma and early rectal cancer and has good prognosis.

Трансанальная эндоскопическая микрохирургия доброкачественных и злокачественных новообразований прямой кишки

Трансанальная эндоскопическая микрохирургия доброкачественных и злокачественных новообразований прямой кишки

Clinicopathological study of 9 cases of prostate cancer involving the rectal wall

BackgroundProstate cancer involving the rectal wall is rare and may lead to diagnostic pitfalls.Case presentationOut of 9504 patients with rectal tumors between January 2003 and January 2015, 9 patients (elderly with a mean age of 74 years) with prostate cancer involving the rectal wall were clinically misdiagnosed with rectal cancer. The lesions were located in the rectum, and included 3 circumferential rectal masses, 1 ulceration lesion, 1 crater-like mass, and 4 protruding lesions. Specimens were acquired using biopsy, fine needle aspiration, or resection. The initial symptoms of these patients included rectal urgency, bowel obstruction, and lower gastrointestinal bleeding. Prostate-related symptoms were not obvious. Histologically, 2 cases showed cancer cell invasion in the mucosa, 1 showed transmural invasion from the mucosa to subserosal soft tissues, and 7 cases had submucosa and muscularis propria involvement. All the 9 cases had muscularis propria involvement. However, there were no intraepithelial neoplasias in the mucosal layer, which is reminiscent of rectal carcinoma. The tumors consisted of small-sized or foamy cells that formed acinus-like, duct-like, and cribriform-like structures. We conducted histological staining and an immunohistochemical analysis for CDX-2, prostate-specific antigen (PSA), P504s, villin, carcinoembryonic antigen, CK-pan, cytokeratin 20, and Ki-67. All tumors were PSA and CK-pan positive, 5 of 9 tumors were P504s-positive, and all tumors were negative for the other markers. All patients underwent standard therapy for prostate cancer after the definitive pathological diagnosis. As of March 31, 2015, 8 patients were alive and 1 had died of prostate cancer 6 months posttreatment.ConclusionsAdenocarcinoma appearing in the rectal wall is not always rectal carcinoma. It is necessary to perform a differential diagnosis for prostate cancer in cases of rectal malignant tumors in elderly male patients. Any treatment should be postponed until the final definitive diagnosis is reached.

Criteria for Assessing the Extent of Tumor Regression in Malignant Tumors of the Rectum

The purpose of our study has been studying criteria for evaluating regression of malignant rectal tumors as a result of neoadjuvant therapy. All materials removed during surgery were analyzed using visual-microscopic and microscopic examination.

Significance of defect closure following transanal local full-thickness excision of rectal malignant tumors.

Transanal excision (TAE) for rectal tumors is increasingly applied and it is generally recommended that the defect following full-thickness excision should be closed. The aim of this study was to compare the complications and anal function following TAE between cases where the defect was closed and those where it was not. A total of 43 consecutive rectal malignant tumor patients eligible for TAE were investigated. Regarding anorectal function, incontinence was assessed using the Wexner score. The defect of the rectum was closed in 21 of the 43 patients. There were no significant differences between the two groups regarding gender, distance from the anal verge, tumor size, diagnosis and tumor site. There was a significantly higher number of postoperative complications of all grades and ≥Clavien-Dindo grade IIIa in the closure group (P=0.02 and 0.04, respectively). Regarding the Wexner score, there was no significant difference between the two groups (P=0.24). Compared with the closure group, the non-closure group had significantly fewer postoperative complications of all grades and ≥Clavien-Dindo grade IIIa. Moreover, there was no significant difference regarding the anorectal function between the two groups. Thus, suturing the rectal defect is not necessarily recommended following TAE.

PTU-006 Glove port trans anal excision of rectal tumours

Introduction Transanal glove port excision is a safe minimally invasive procedure for excising rectal tumours that avoids major rectal surgeries and its complications. The aim of this study is to review a single Centre experience with Trans Anal Glove Port excision of rectal tumours. Method Between 2011–2014, 11 patients underwent resection of benign (N = 9) or Malignant (N = 2) rectal tumours, located above the dentate line to 14 cm. The mean follow up period was between 6–12 months. Glove port was constructed using circular anal dilator, standard surgical glove and a wound protector retractor. Results All the patients underwent Glove port transanal excision of rectal tumours. Male: Female ratio was 10:1. Average age of patients was 63 years. None of the patients in the series underwent conversion to radical surgery. Full thickness excision of the tumour was performed in 9 patients and the other two underwent submucosal excision. During the follow up period between 6–12 months, 1 patient had recurrent tubulo villous adenoma, which needed further excision of the adenoma. In two patients who had a planned glove port excision for a presumed benign rectal polyp (Tubulo villous adenoma), The final histology showed an adenocarcinoma on a background of Tubulo-villous adenoma. Both the Patients underwent further staging investigations, one patient had a further chemo-radiotherapy and the other patient did not need any further treatment. Both are under close surveillance with no recurrence. Post-operative complications were only mild which included bleeding and mucus discharge. Conclusion Glove port Trans anal excision is a safe, effective and cheap technique useful in excising rectal tumours with good clearance and full thickness excision of the rectal wall where necessary. It helps avoid major rectal resections with its attendant complications, in many cases. Disclosure of interest None Declared. Reference Alessandro C, Daniela M, Michele M, et al . Glove port technique for transanal endoscopic microsurgery. Int J Surg Oncol . 2012;2012:Article ID 383025,1–4

A training programme for operating theatre personnel in transanal endoscopic operation procedures for local excision of rectal tumours.

The transanal endoscopic operation (TEO) is a minimal access surgical procedure for the removal of benign and early malignant rectal tumours (Nieuwenhuis et al 2009). This surgery involves specialist equipment, set up and positioning by the perioperative team. We report on and evaluate the first ever TEO course designed specifically for theatre practitioners.

Transanal Endoscopic Microsurgery After Neoadjuvant Chemoradiotherapy for Rectal Cancer.

Radical rectal resection following neoadjuvant chemoradiation therapy (CRT) for locally advanced rectal cancer is accompanied by relatively high morbidity. Local excision of rectal cancer may be more appropriate for some frail patients with severe comorbidities. Transanal endoscopic microsurgery (TEM), consisting of local excision of selected rectal cancers, has been associated with low rates of postoperative complications. Because neoadjuvant CRT for rectal cancer may be associated with increased complications, the suitability of TEM following CRT is still unclear. In this study we aimed to assess the clinical outcomes of patients undergoing TEM following neoadjuvant CRT. This study retrospectively analyzed all patients undergoing TEM for malignant rectal tumor in our institution between 2004 and 2010. They were divided into those who received CRT (CRT group) and those without CRT (non-CRT group). Demographics and clinical data were compared. Forty-four of 97 patients who underwent TEM were included: 13 CRT and 31 non-CRT. Age, comorbidities, and the duration of the procedure were similar for both groups. There were no significant group differences in tumor diameter (2.1 cm [range, 0.5-3.5 cm] and 2.9 cm [range, 0.5-4.2 cm], respectively; P=.125) or distance of the lower part of the tumor from the anal verge (6.7 cm [range, 5-10 cm] and 7.7 cm [range, 5-15 cm], respectively; P=.285). Two non-CRT patients had peritoneal entry, and 1 of them underwent protective ileostomy because of insecure rectal defect closure. One non-CRT patient underwent a re-operation for postoperative bleeding. The other perioperative complications were minor and included urinary retention requiring catheter placement (2 patients in each group), pulmonary edema (1 non-CRT patient), and pneumonia (1 non-CRT patient). All complications were managed conservatively. There was no wound disruption, major complication, or mortality in either group. With proper patient selection, TEM can be performed safely following CRT, without major complication or increased postoperative morbidity.

Synchronous collision neuroendocrine tumor and rectal adenocarcinoma: a case report.

Collision tumors are thought to arise from the accidental meeting of two independent tumors. Adenocarcinoma is the most common malignant rectal tumor, while neuroendocrine tumor (NET) is relatively rare. Due to the endoscopy and reporting, the overall incidence of NETs was increasing recently but still less than 1 per 100,000. This means that a combination of an adenocarcinoma and NET is a very rare finding and an actual collision of these tumors even more so. We report here a highly unusual case of a 64-year-old woman who had collision tumors composed of a primary rectal adenocarcinoma and NET showing a "side by side" pattern. Resection margins are free of both the tumors. The postoperative course was uneventful. The patient underwent a protocol CT scan at 3months after surgery, which did not show any recurrence. Both the malignant adenocarcinoma and the NET would make a great influence in the rest lifetime and a follow up will be continued, although the CT did not show any recurrence until now. To the best of our knowledge, this is the first reported case of such an occurrence.

Anorectal function and outcomes after transanal minimally invasive surgery for rectal tumors.

BACKGROUND:Transanal endoscopic microsurgery is a minimally invasive technique that allows full-thickness resection and suture closure of the defect for large rectal adenomas, selected low-risk rectal cancers, or small cancers in patients who have a high risk for major surgery. Our aim, in the given prospective study was to report our initial clinical experience with TAMIS, and to evaluate its effects on postoperative anorectal functions.MATERIALS AND METHODS:In 10 patients treated with TAMIS for benign and malignant rectal tumors, preoperative and postoperative anorectal function was evaluated with anorectal manometry and Cleveland Clinic Incontinence Score.RESULTS:The mean distance of the tumors from the anal verge was 5.6 cm, and mean tumor diameter was 2.6 cm. All resection margins were tumor free. There was no difference in preoperative and 3-week postoperative anorectalmanometry findings; only mean minimum rectal sensory volume was lower at 3 weeks after surgery. The Cleveland Clinic Incontinence Score was normal in all patients except one which resolved by 6 weeks after surgery.The mean postoperative follow-up was 28 weeks without any recurrences.CONCLUSION:Transanal minimally invasive surgery is a safe and effective procedure for treatment of rectal tumors and can be performed without impairing anorectal functions.

Transanal endoscopic microsurgery

To analyze the immediate and remote results of transanal endoscopic microsurgical intervantions and its role in treatment of rectal tumors. The results of transanal endoscopic microsurgery in 56 patients with rectal tumors were studied. Adenoma and adenocarcinoma were observed in 45 (80%) and 11 (20%) patients respectively. Mean height of tumor lower edge placement was 8.6 ± 0.3 cm from anus, mean diameter - 3.7 ± 0.3 cm. All patients underwent full-layer resection of rectum. Postoperative complications were observed in 4 (7%) patients. There were no deaths. Transanal endoscopic microsurgery is modern, adequate and effective treatment of benign and early forms of malignant rectal tumors. It is associated with lower incidence of complications and recurrence under condition of careful selection of patients. Based on obtained results we recommend surgeons to apply this technique only in case of tumor placement below 10-11 cm from anus and tumor's diameter up to 3-4 cm to minimize risk of complications and recurrences. Full-layer resection of rectum is recommended in all cases of operations for benign tumors because of there is high risk of latent malignancy.

Primary rectal cancer local staging

The treatment of patients with a malignant rectal tumor has evolved over the past few years. The role of medical imaging techniques, notably MRI, has become increasingly important in the preoperative assessment of rectal tumors. Radiologists are finding that their presence is requested more and more frequently at multidisciplinary team meetings for decision-making on the treatment of these tumors and therefore they must have a grounding in the therapeutic issues involved. Locoregional assessment of malignant rectal tumors may be performed prior to initiating treatment or as a re-evaluation following neoadjuvant therapy. We are interested in the assessment of the initial locoregional extension of these rectal tumors and we place much emphasis on the ability to identify MRI criteria which determine the patient's prognosis and treatment. We will also examine the advantages of MRI as well as its limits in this assessment.

Transanal Endoscopic Operations for Rectal Tumours

BackgroundTransanal endoscopic operation (TEO) may be the technique of choice for the treatment of rectal lesions, both benign and selected malignant lesions, with similar survival rates to conventional surgery but with lower morbidity. MethodsIn this article we present a series of 70 patients operated on with this procedure (TEO) in our centre. The indications were benign rectal lesions and malignant lesions at early stages (T1) 86%. The surgical procedure was performed with the transanal endoscopic operation platform (TEO; Karl Storz, Tüttlingen, Germany) and ultrasonic scalpel (Harmonic scalpel, Ethicon Endo-surgery, …). ResultsThe indication in 43 patients was a benign lesion (adenoma), in the other 27 the diagnosis was adenocarcinoma. After the resection, 61% of the series had a malignant lesion in the pathology report: 13 patients of the 43 with a benign lesion initially had a malignant lesion in the pathology report. Postoperative morbidity was 36%, Clavien III (5.7%). 3 patients (4%) needed emergency surgery.All of the benign lesions were completely excised, but 7 malignant lesions had resection margin involvement The median follow-up time was 26.4 months (range 1–71 months), the overall recurrence for benign tumours was 9%, 8% for malignant pT1 and 12.5% for malignant pT2. Early salvage surgery was performed on 8 patients. ConclusionsTEO allows us to excise benign rectal lesions that could not be excised with a conventional approach (endoscopic or transanal resection) with a low morbidity rate. TEO can be used for malignant rectal tumours in early stages (pT1) with pathological confirmation.