Why do patients with urinary diversions have an increased risk of bone fracture? A systematic review on risk factors for osteoporosis and bone mineral density loss in this group of patients.

INTRODUCTION: Patients undergoing radical cystectomy with urinary diversions (UD) are at increased risk of bone fractures compared to the general population. Although a loss of bone mineral density (BMD) has been described in patients with UD, we still do not know with certainty why these patients follow this tendency. OBJECTIVE: We performed a systematic review of the available literature to analyze the prevalence of osteoporosis and bone alterations in patients with ileal UD and the possible associated risk factors. EVIDENCE ACQUISITION: We systematically searched PubMed® and Cochrane Library for original articles published before December 2022 according to PRISMA guidelines. EVIDENCE SYNTHESIS: A total of 394 publications were identified. We selected 12 studies that met the inclusion criteria with 496 patients included. Six of the twelve studies showed decreased BMD values. Prevalence of osteoporosis was specified in three articles, with values ranging ​​from 0% to 36%. Risk factors such as age, sex, body mass index, metabolic acidosis and renal function appear to have an impact on bone tissue reduction, while type of UD, follow-up, 25-hydroxyvitamin D and parathormone had less evidence or contradictory data. The heterogeneity of the studies analyzed could led to interpretation bias. CONCLUSIONS: UD are associated with multiple risk factors for osteoporosis and bone fractures. Identifying patients at highest risk and establishing diagnostic protocols in routine clinical practice are essential to reduce the risk of fractures and the resulting complications.

Prevalence of metabolic acidosis in ileal diversions more than one year after radical cystectomy and associated secondary metabolic effects.

INTRODUCTION AND OBJECTIVE: Metabolic acidosis (MA) is a well-known complication in patients with ileal urinary diversions. It is common in the early postoperative stages and decreases over time. Our objective is to investigate the prevalence of MA after more than one year of follow-up, identify the associated risk factors, and analyze its secondary metabolic consequences. MATERIALS AND METHODS: We conducted an observational study between January 2018 and September 2022 following the STROBE guidelines. MA was defined as a serum bicarbonate level ​​<22mEq/L. Finally, we analyzed 133 patients with a mean follow-up of 55.24 ± 42.36 months. RESULTS: MA was observed in 16 (12%) patients. Patients with and without MA were comparable in age, sex, and follow-up time. The group with MA presented a higher rate of anemia (68,75% vs 19,65%, p < 0.001) and renal failure (100% vs 45,29%, p < 0.001), statistically significant higher levels of serum creatinine, chloride, potassium, parathyroid hormone, and phosphorus but lower serum values ​​of hemoglobin, renal glomerular filtration rate, total cholesterol, vitamin D, calcium, and albumin (all p < 0.05). Renal glomerular filtration rate was the only independent risk factor related to the development of MA (OR 0.914; 95% CI 0.878-0.95; p < 0.0001), proving a close correlation with venous bicarbonate values ​​(r = 0.387, p < 0.001). CONCLUSIONS: MA is a little prevalent disorder in ileal urinary diversions more than one year after radical cystectomy is performed but it has secondary consequences on hematologic, renal, protein, lipid, and bone metabolism. We recommend to a close follow-up in patients with renal failure for early diagnosis and treatment.

Laparoscopic and robotic intracorporeal resection and end-to-end anastomosis in left colectomy: a prospective cohort study - stage 2a IDEAL framework for evaluating surgical innovation.

PURPOSE: To analyze the safety and feasibility of intracorporeal resection and anastomosis in upper rectum, sigmoid, and left colon surgery, via both laparoscopic and robotic approaches. The secondary aim was to assess possible short-term differences between laparoscopic versus robotic surgery. METHODS: A prospective observational cohort study according to IDEAL framework exploration and assessment stage (Development, stage 2a), evaluating and comparing the laparoscopic approach and the robotic approach in left colon, sigmoid, and upper rectum surgery with intracorporeal resection and end-to-end anastomosis. Demographic, preoperative, surgical, and postoperative variables of patients undergoing laparoscopic and robotic surgery are described and compared according to the surgical technique used. RESULTS: Between May 2020 and March 2022, seventy-nine patients were consecutively included in the study, 41 operated via laparoscopy (laparoscopic left colectomy: LLC) and 38 by robotic surgery (robotic left colectomy: RLC). There were no statistically significant differences between the two groups in terms of demographic variables. In surgical variables, the median surgical times differed significantly: 198 min (SD 48 min) for LLC vs. 246 min (SD 72 min) for RLC (p = 0.01, 95% CI: - 75.2 to - 20.5)). The only significant difference regarding postoperative complications was a higher degree of relevant morbidity in the LLC (Clavien-Dindo > II (14.6% vs. 0%, p = 0.03) and Comprehensive Complication Index (IQR 22 vs. IQR 0, p = 0.03). The pathological results were similar in both approaches. CONCLUSION: Laparoscopic and robotic intracorporeal resection and anastomosis are feasible and safe, and obtain similar surgical, postoperative, and pathological results than described in literature. However, morbidity seems to be higher in LLC group with fewer relevant postoperative complications. The results of this study enable us to proceed to stage 2b of the IDEAL framework. CLINICAL TRIAL REGISTRATIONS: The study is registered in Clinical trials with the registration code NCT0445693.

Parastomal hernia prevention with permanent mesh in end colostomy: failure with late follow-up of cohorts in three randomized trials.

PURPOSE: Short-term results have been reported regarding parastomal hernia (PH) prevention with a permanent mesh. Long-term results are scarce. The objective was to assess the long-term PH occurrence after a prophylactic synthetic non-absorbable mesh. METHODS: Long-term data of three randomized controlled trials (RCTs) were collected. The primary outcome was the detection of PH based exclusively on a radiological diagnosis by computed tomography (CT) performed during the long-term follow-up. The Kaplan-Meier method was used for the comparison of time to diagnosis of PH according to the presence of mesh vs. no-mesh and the technique of mesh insertion: open retromuscular, laparoscopic keyhole, and laparoscopic modified Sugarbaker. RESULTS: We studied 121 patients (87 men, median age 70 years), 82 (67.8%) of which developed a PH. The median overall length of follow-up was 48.5 months [interquartile range (IQR) 14.4-104.9], with a median time until PH diagnosis of 17.7 months (IQR 9.3-49.0). The survival analysis did not show significant differences in the time to development of a PH according to the presence or absence of a prophylactic mesh neither in the overall study population (log-rank, P = 0.094) nor in the groups of each technique of mesh insertion, although according to the surgical technique, a higher reduction in the appearance of PH for the open retromuscular technique was found (log-rank, P = 0.001). CONCLUSION: In the long-term follow-up placement of a non-absorbable synthetic prophylactic mesh in the context of an elective end colostomy does not seem effective for preventing PH.

Metabolic acidosis after ileal urinary diversion and radical cystectomy. Do we know as much as we think we do? A systematic review.

Urine contact with the mucosa of the urinary diversion (UD) after radical cystectomy (RC) produces different ion exchanges that favor the development of metabolic acidosis (MA). This phenomenon is a frequent cause of hospital readmission and short/long-term complications. We performed a systematic review of MA in RCs with ileal UD, analyzing its prevalence, diagnosis, risk factors and treatment. We systematically searched Pubmed® and Cochrane Library for original articles published before May 2022 according to PRISMA guidelines. A total of 421 articles were identified. We selected 25 studies that met the inclusion criteria involving 5811 patients. Obtaining precise data on the prevalence of MA is difficult, largely due to the heterogeneity of the diagnostic criteria used given the diversity of studies analyzed. Development of MA is multifactorial. In the early period, MA is more prevalent in patients with UD with longer ileal segments, better urinary continence, and impaired renal function. Age and diabetes are risk factors associated with MA in later periods. MA is the most common cause of second or more hospital readmissions. Prophylaxis with oral bicarbonate for three months in patients at risk could improve these results. Although MA after ileal UD is a well-known condition, this review highlights the need to implement homogeneous criteria for the diagnosis, follow-up, and treatment, in addition to protocolizing prevention/prophylaxis strategies in patients at risk.

Short-term outcomes of chemoradiotherapy and local excision versus total mesorectal excision in T2-T3ab,N0,M0 rectal cancer: a multicentre randomised, controlled, phase III trial (the TAU-TEM study).

BACKGROUND: The standard treatment of T2-T3ab,N0,M0 rectal cancers is total mesorectal excision (TME) due to the high recurrence rates recorded with local excision. Initial reports of the combination of pre-operative chemoradiotherapy (CRT) and transanal endoscopic microsurgery (TEM) have shown reductions in local recurrence. The TAU-TEM study aims to demonstrate the non-inferiority of local recurrence and the improvement in morbidity achieved with CRT-TEM compared with TME. Here we describe morbidity rates and pathological outcomes. PATIENTS AND METHODS: This was a prospective, multicentre, randomised controlled non-inferiority trial including patients with rectal adenocarcinoma staged as T2-T3ab,N0,M0. Patients were randomised to the CRT-TEM or the TME group. Patients included, tolerance of CRT and its adverse effects, surgical complications (Clavien-Dindo and Comprehensive Complication Index classifications) and pathological results (complete response in the CRT-TEM group) were recorded in both groups. Patients attended follow-up controls for local and systemic relapse. TRIAL REGISTRATION: NCT01308190. RESULTS: From July 2010 to October 2021, 173 patients from 17 Spanish hospitals were included (CRT-TEM: 86, TME: 87). Eleven were excluded after randomisation (CRT-TEM: 5, TME: 6). Modified intention-to-treat analysis thus included 81 patients in each group. There was no mortality after CRT. In the CRT-TEM group, one patient abandoned CRT, 1/81 (1.2%). The CRT-related morbidity rate was 29.6% (24/81). Post-operative morbidity was 17/82 (20.7%) in the CRT-TEM group and 41/81 (50.6%) in the TME group (P < 0.001, 95% confidence interval 42.9% to 16.7%). One patient died in each group (1.2%). Of the 81 patients in the CRT-TEM group who received the allocated treatment, 67 (82.7%) underwent organ preservation. Pathological complete response in the CRT-TEM group was 44.3% (35/79). In the TME group, pN1 were found in 17/81 (21%). CONCLUSION: CRT-TEM treatment obtains high pathological complete response rates (44.3%) and a high CRT compliance rate (98.8%). Post-operative complications and hospitalisation rates were significantly lower than those in the TME group. We await the results of the follow-up regarding cancer outcomes and quality of life.

Experimental study of the quantification of indocyanine green fluorescence in ischemic and non-ischemic anastomoses, using the SERGREEN software program.

Tissue ischemia is a key risk factor in anastomotic leak (AL). Indocyanine green (ICG) is widely used in colorectal surgery to define the segments with the best vascularization. In an experimental model, we present a new system for quantifying ICG fluorescence intensity, the SERGREEN software. Controlled experimental study with eight pigs. In the initial control stage, ICG fluorescence intensity was analyzed at the level of two anastomoses, in the right and in the left colon. Control images of the two segments were taken after ICG administration. The images were processed with the SERGREEN program. Then, in the experimental ischemia stage, the inferior mesenteric artery was sectioned at the level of the anastomosis of the left colon. Fifteen minutes after the section, sequential images of the two anastomoses were taken every 30 min for the following 2 h. At the control stage, the mean scores were 134.2 (95% CI 116.3-152.2) for the right colon and 147 (95% CI 134.7-159.3) for the left colon (p = 0.174) (Scale RGB-Red, Green, Blue). The right colon remained stable throughout the experiment. In the left colon, intensity fell by 47.9 points with respect to the pre-ischemia value (p < 0.01). After the first post-ischemia determination, the values of the ischemic left colon remained stable throughout the experiment. The relative decrease in ICG fluorescence intensity of the ischemic left colon was 32.6%. The SERGREEN program quantifies ICG fluorescence intensity in normal and ischemic situations and detects differences between them. A reduction in ICG fluorescence intensity of 32.6% or more was correlated with complete tissue ischemia.

When should indocyanine green be assessed in colorectal surgery, and at what distance from the tissue? Quantitative measurement using the SERGREEN program.

BACKGROUND: Suture dehiscence is one of the most feared postoperative complications. Correct intestinal vascularization is essential for its prevention. Indocyanine green (ICG) is one of the methods used to assess vascularization, but this assessment is usually subjective. Our group designed the SERGREEN program to obtain an objective measurement of the degree of vascularization. We do not know how long after ICG administration the fluorescence of the tissues should be evaluated, or how far away the measurement should be performed. The aim of this study is to establish the optimal moment and distance for analyzing the fluorescence saturation of ICG. METHODS: Prospective observational study in patients undergoing elective laparoscopic colorectal surgery. The optimal time for ICG analysis was tested in a sample of 20 patients (10 right colon and 10 left colon), and the optimal distance in a sample of ten patients. ICG was administered intravenously, and colon vascularization was quantified using SERGREEN; RGB (Red, Green, Blue) encoding was used. The intensity curve of the ICG was analyzed for ten minutes after its administration. Distances of 1, 3, and 5 cm were tested. RESULTS: The intensity of fluorescence increased until 1.5 min after ICG administration (reaching figures of 112.49 in the right colon and 93.95 in the left). It then remained fairly stable until 3.5 min (98.49 in the right and 83.35 in the left), at which point it began to decrease gradually. ICG saturation was inversely proportional to the distance between the camera and the tissue. The best distance was 5 cm, where the confidence interval was narrower [CI 86.66-87.53]. CONCLUSION: The optimal time for determining ICG in the colon is between 1.5 and 3.5 min, in both right and left colon. The optimal distance is 5 cm. This information will help to establish parameters of comparison in normal and pathological situations.

Long-term outcomes of colonic stent as a "bridge to surgery"for left-sided malignant large-bowel obstruction.

BACKGROUND: The role of self-expandable metallic stents (SEMS) as a bridge to surgery in left-sided malignant colonic obstruction is still debated. Here we assess the morbidity, mortality and long-term oncological outcomes as a bridge to surgery for patients with left-sided malignant colonic obstruction. METHOD: Prospective observational study with retrospective analysis of patients with left-sided malignant colonic obstruction undergoing stenting. April 2006-April 2018. We assessed all patients with intent-to treat and per protocol analyses and long-term follow-up variables. RESULTS: Colonic stent was performed in 117 patients. Technical and clinical success of SEMS placement: 94.4% (111/117), only 4.3% perforation. Elective surgery resection following the strategy of SEMS was performed in 83.8% (98/117). A laparoscopic approach was: 25.6% (30/117); 76.9% in the last two years. Primary anastomosis rate: 92.8% (91/98), without protective stoma in any patients. Anastomotic leakage rate: 8.2% (8/97). Median follow-up: 44.5 months (range 0-109). The intent-to-treat analysis showed overall and disease-free survival rates of 63.3% (74/117) and 58.1% (68/117), and local and distant recurrence rates: 9.4% (11/117) and 58.1% (68/117). In the per protocol analysis, overall and disease-free survival rates: 63.2% (62/98) and 60.2% (58/98), and local and distant recurrence rates: 10.2% (10/98) and 36.7% (36/98). Disease progression was predominantly observed during the first 5 years' follow-up as disease recurrence; after five years' follow-up, 60% of the patients were disease-free. CONCLUSIONS: According to the results of the study SEMS as a bridge to surgery achieves perioperative results comparable to non-occlusive colonic cancer surgery and does not adversely affect long-term oncological outcomes. Further investigations are needed.

A single-center prospective observational study on the effect of trimodal prehabilitation in colorectal surgery. / Estudio observacional prospectivo unicéntrico sobre el efecto de la prehabilitación trimodal en cirugía colorrectal.

INTRODUCTION: A trimodal prehabilitation protocol was designed with the aim to evaluate whether it contributes to reducing postoperative morbidity, to evaluate the effect of prehabilitation on overall hospital stay, and to analyze the evolution of functional capacity before and after surgery. METHODS: A single-center observational study of patients with colorectal cancer who underwent surgery with curative intent after a trimodal prehabilitation protocol. We collected data for postoperative morbidity according to the Comprehensive Complication Index and hospital stay, which were compared with a historical matrix. Functional capacity data were also collected before and after the application of the prehabilitation protocol. RESULTS: Compared to the historical population, the overall Comprehensive Complication Index was reduced from 13.2 to 11.5, which was statistically significant. Analyzed by morbidity type, all decreased in percentage, although without achieving significance (surgical site infection from 11.7% to 8.4%, nosocomial infection 15.8 to 10% and medical morbidity 8.6% to 4.2%). The overall hospital stay went from 6 to 4 days, and the decrease in the percentage of patients who prepared at home was statistically significant in both cases. CONCLUSIONS: Trimodal prehabilitation can contribute to lowering the postoperative morbidity and overall hospital stay of patients undergoing colorectal cancer surgery.

A real world analysis of recurrence risk factors for early colorectal cancer T1 treated with standard endoscopic resection.

BACKGROUND AND STUDY AIM: Currently, endoscopic resection of early colorectal cancer defined as carcinoma with limited invasion of the mucosa (Tis) and submucosa (T1) is possible. However, lymph node spreading increases to 16.2% of cases when tumor invades the submucosa. We analyzed the previously identified factors for lymph node dissemination and recurrence, in our population. PATIENTS AND METHODS: We analyzed retrospectively all patients with T1 tumors, treated at our center with endoscopic resection and some with additional surgery between January 2006 and January 2018. Statistical analysis was performed using IBM SPSS Statistics 25.0. RESULTS: One hundred fifty-nine patients were treated with endoscopic resection, 56.6% with additional surgery. The mean age was 68.74 years and 69. 9% were male. All patients who underwent additional surgery presented negative margins and 8.8% presented positive lymph nodes. In a mean follow-up of 23.36 months, 13 patients had relapsed. The risk of relapse did not differ between patients treated with additional surgery from those who only underwent endoscopic resection (p = 0.506). On the other hand, lymph node dissemination (p = 0.007) and a positive endoscopic margin (p = 0.01) were independent risk factors for relapse. There was a positive association between lymph node dissemination and lymphatic (p = 0.07), vascular (p = 0.007), and perineural (p = 0.001) invasion and also with degree of histological differentiation (p = 0.001). CONCLUSION: In our study, lymphatic, vascular, and perineural invasion and also the degree of histological differentiation were associated with lymph node dissemination. However, the only independent risk factors for long-term recurrence were a positive margin and lymph node dissemination.

A scoring system to predict complex transanal endoscopic surgery.

BACKGROUND: Since the introduction of screening for colorectal cancer, the use of transanal endoscopic surgery (TEM) has become increasingly popular. However, the technical difficulty of this surgery varies widely. The few studies of learning curve in TEM have produced very disparate results. The aim of this study is to distinguish between straightforward and complex procedures, in order to refer more difficult cases to centers with greater experience. METHOD: Observational study with prospective data collection and retrospective analysis was carried out between June 2004 and January 2019. All TEMs performed on rectal tumors were included. The complexity of the procedure was defined according to the weighted mean surgical time for each surgeon. A predictive model of complexity was established, with a score higher than 5 indicating a complex lesion. RESULTS: During the study period, 773 TEMs were performed, 708 of which met the study's inclusion criteria. One hundred and three tumors were defined as complex. Predictors of complexity were as follows: male sex (OR: 1.78, 95% CI 1.1-2.9, score: 1), tumor size > 5 cm (OR: 5.1, 95% CI 3.2-8.2, score: 4), TEM for recurrence (OR: 6.3, 95% CI 2.3-16.7, score: 5), and distance from the upper margin of the tumor to the anal verge > 15 cm (OR: 1.6, 95% CI 0.96-2.7, score: 1). CONCLUSIONS: Rather than establishing the learning curve merely in terms of the number of TEM procedures performed, it is important to consider the surgical difficulty of the interventions. To this end, it is essential to differentiate simple TEMs from the complex ones.

Transanal endoscopic microsurgery in very large and ultra large rectal neoplasia.

BACKGROUND: Transanal endoscopic microsurgery (TEM) has become the treatment of choice for benign rectal lesions and early rectal cancer (T1). The size classification of rectal polyps is controversial. Some articles define giant rectal lesions as those larger than 5 cm, which present a significantly increased risk of complications. The aim of this study was to evaluate the feasibility of TEM in these lesions. METHODS: An observational descriptive study with prospective data collection evaluating the feasibility of TEM in large rectal adenomas was performed between June 2004 and September 2018. Patients were assigned to one of the three groups according to size: < 5 cm, very large (5-7.9 cm) and ultra-large (≥ 8 cm). Descriptive and comparative analyses between groups were performed. RESULTS: TEM was indicated in 761 patients. Five hundred and seven patients (66.6%) with adenoma in the preoperative biopsy were included in the study. Three hundred and nine out of 507 (60.9%) tumors < 5 cm, 162/507 (32%) very large tumors (5-7.9 cm) and 36/507 (7.1%) ultra-large tumors (≥ 8 cm) were reviewed. Morbidity increased with tumor size: 17.5% in tumors < 5 cm, 26.5% in those 5-7.9 cm, and 36.1% in those > 8 cm. Peritoneal perforation, fragmentation, free margins and stenosis were also more common in very large and ultra-large tumors (p < 0.001). There were no statistical differences between the groups in the definitive pathology (p = 0.38). CONCLUSIONS: TEM in these large tumors is associated with higher rates of morbidity, peritoneal perforation, free margins and stenosis. Although these tumors do not require total mesorectal excision and are eligible for TEM, the surgery must be carried out by experienced surgeons.

Transanal endoscopic micro-surgery in elderly and very elderly patients: a safe option? Observational study with prospective data collection.

BACKGROUND: Although the incidence of colorectal cancer increases with the patient's age, the elderly continue to be less likely to be scheduled for surgery. Transanal endoscopic micro-surgery (TEM) is a surgical alternative to total mesorectal excision (TME) in early stage rectal cancer and/or in selected patients that could decrease morbidity and mortality rates in this group of patients. Our main objective is to assess the safety and feasibility of TEM in elderly (75-84 years) and very elderly (≥ 85 years) patients. METHODS: Observational study was conducted with prospective data collection of all consecutive patients who underwent TEM between April 2004 and January 2017. Patients were assigned to groups according to age. Descriptive and comparative analyses between groups were performed. RESULTS: We analyzed 693 patients, 429 patients < 75 years (61.9%), 220 patients between the ages of 75 and 84 (31.7%), and 44 patients ≥ 85 years old (6.3%). The tendency in our series is to increase comorbidities with age. Palliative or consensus intent was more frequently performed in elderly (10.5%, 34/220), and very elderly (45.4%, 20/44), compared with the youngest (6.3%, 27/429), (p < 0.001). Global morbidity presented an increasing trend related to age from 20.3% in < 75 years, to 25.9% in elderly and 34.1% in very elderly. Surgical complications were recorded in 18.5% (128/693) of patients with no significant differences between groups. The most common one was rectal bleeding 16.1% (111/693). Significant differences were found in non-surgical complications, recorded in 7.3% (16/220) in the elderly, and 15.9% (7/44) in the group above 84 years (p = 0.013). CONCLUSIONS: TEM presents acceptable morbidity rates mainly due to non-surgical-related adverse effects in elderly and very elderly patients and may be a feasible and safe alternative in this population in both curative and non-curative indications.

Study protocol for a multicenter prospective controlled and randomized trial of transanal total mesorectal excision versus laparoscopic low anterior resection in rectal cancer.

PURPOSE: Compared with the open approach, laparoscopic total mesorectal excision (TME) achieves faster patient recovery, reduces morbidity rates, and shortens hospital stay. However, in laparoscopic low anterior resection (L-LAR), conversion to open surgery is required in almost 20% of cases. Transanal TME (Ta-TME) combined with laparoscopy, also called hybrid natural orifice transluminal endoscopic surgery (NOTES), is a less invasive procedure that can overcome some of the limitations of laparoscopic rectal surgery. In this study, we aim to determine whether Ta-TME has a lower rate of conversion to open surgery than L-LAR, and thus achieves faster patient recovery without altering the pathological, functional, or oncological results. The main objective is to compare the results for conversion to open surgery between Ta-TME and L-LAR. METHODS: Multicenter, prospective randomized controlled study of patients diagnosed with rectal adenocarcinoma who will be randomly allocated to Ta-TME or L-LAR groups after the application of inclusion and exclusion criteria. The main endpoint is conversion to open surgery and the secondary endpoints are general morbidity and mortality and hospital stay. Demographic, surgical, and pathological variables will also be studied, along with quality of life and survival. A sample size of 53 patients per group is calculated. With an estimated loss of 10%, the final sample required will be 116 patients. CONCLUSIONS: Ta-TME achieves a lower conversion rate to open surgery than L-LAR, thus improving patient recovery and reducing overall morbidity. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02550769. Registration no. Ethical and Clinical Research Committee, Parc Taulí University Hospital: ID 2014/064.

Transanal endoscopic surgery is effective and safe after endoscopic polypectomy of potentially malignant rectal polyps with questionable margins.

AIM: To determine the percentage of residual lesion observed in the pathology study of transanal endoscopic surgery (TEM) specimens after endoscopic polypectomy of malignant rectal polyps with questionable margins, and the need for further surgery. Secondary aims: to determine the morbidity and mortality associated with this procedure and to identify the percentage of recurrence after excision by TEM. METHODS: Observational study with prospective data collection of all patients undergoing TEM after endoscopic polypectomy for malignant rectal polyps or non-invasive high-grade neoplasia, from January 2004 to December 2016. An en bloc full-thickness wall excision of the scar was performed. Variables recorded: histology of TEM specimen, 30-day morbidity and mortality according to the Clavien-Dindo classification, need for salvage surgery and recurrence. RESULTS: Fifty out of 690 patients undergoing TEM during the study period (36 adenocarcinomas, five non-invasive high-grade neoplasias and 9 neuroendocrine tumors) were included. Post-surgery histology showed residual lesion in 21 (42%) patients: 7 neuroendocrine tumors, 10 adenomas and 4 adenocarcinomas (two pT1, one pT2 and one pT3). The pT2 and pT3 patients (4%) underwent salvage surgery. No recurrence was observed, and mean follow-up was 29.1Â ± 21.6 months. The 30-day morbidity rate was 14%, but 4/7 with Clavien-Dindo grade I. CONCLUSIONS: After endoscopic polypectomy of malignant rectal polyps with questionable margins, the presence of residual lesion in the pathology study of transanal resection specimens is high. TEM with full-thickness resection of these lesions is an appropriate treatment, allowing disease control and achieving minimal morbidity.

Non-inferiority multicenter prospective randomized controlled study of rectal cancer T2-T3s (superficial) N0, M0 undergoing neoadjuvant treatment and local excision (TEM) vs total mesorectal excision (TME).

PURPOSE: The standard treatment of rectal adenocarcinoma is total mesorectal excision (TME), in many cases requires a temporary or permanent stoma. TME is associated with high morbidity and genitourinary alterations. Transanal endoscopic microsurgery (TEM) allows access to tumors up to 20 cm from the anal verge, achieves minimal postoperative morbidity and mortality rates, and does not require an ostomy. The treatment of T2, N0, and M0 cancers remains controversial. Preoperative chemoradiotherapy (CRT) in association with TEM reduces local recurrence and increases survival. The TAU-TEM study aims to demonstrate the non-inferiority of the oncological outcomes and the improvement in morbidity and quality of life achieved with TEM compared with TME. METHODS: Prospective, multicenter, randomized controlled non-inferiority trial includes patients with rectal adenocarcinoma less than 10 cm from the anal verge and up to 4 cm in size, staged as T2 or T3-superficial N0-M0. Patients will be randomized to two areas: CRT plus TEM or radical surgery (TME). Postoperative morbidity and mortality will be recorded and patients will complete the quality of life questionnaires before the start of treatment, after CRT in the CRT/TEM arm, and 6 months after surgery in both arms. The estimated sample size for the study is 173 patients. Patients will attend follow-up controls for local and systemic relapse. CONCLUSIONS: This study aims to demonstrate the preservation of the rectum after preoperative CRT and TEM in rectal cancer stages T2-3s, N0, M0 and to determine the ability of this strategy to avoid the need for radical surgery (TME). TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01308190. Número de registro del Comité de Etica e Investigación Clínica (CEIC) del Hospital universitario Parc Taulí: TAU-TEM-2009-01.