Impact of pelvic radiotherapy on morbidity and durability of sphincter preservation after coloanal anastomosis for rectal cancers

Machine learning model for prediction of permanent stoma after anterior resection of rectal cancer: A multicenter study

BACKGROUND

The conversion from a temporary to a permanent stoma (PS) following rectal cancer surgery significantly impacts the quality of life of patients. However, there is currently a lack of practical preoperative tools to predict PS formation. The purpose of this study is to establish a preoperative predictive model for PS using machine learning algorithms to guide clinical practice.

METHODS

In this retrospective study, we analyzed clinical data from a total of 655 patients who underwent anterior resection for rectal cancer, with 552 patients from one medical center and 103 from another. Through machine learning algorithms, five predictive models were developed, and each was thoroughly evaluated for predictive performance. The model with superior predictive accuracy underwent additional validation using both an independent testing cohort and the external validation cohort. The Shapley Additive exPlanations (SHAP) approach was employed to elucidate the predictive factors influencing the model, providing an in-depth visual analysis of its decision-making process.

RESULTS

Eight variables were selected for the construction of the model. The support vector machine (SVM) model exhibited superior predictive performance in the training set, evidenced by an AUC of 0.854 (95 % CI:0.803-0.904). This performance was corroborated in both the testing set and external validation set, where the model demonstrated an AUC of 0.851 (95%CI:0.748-0.954) and 0.815 (95%CI:0.710-0.919), respectively, indicating its efficacy in identifying the PS.

CONCLUSIONS

The model(https://yangsu2023.shinyapps.io/psrisk/) indicated robust predictive performance in identifying PS after anterior resection for rectal cancer, potentially guiding surgeons in the preoperative stratification of patients, thus informing individualized treatment plans and improving patient outcomes.

Determination of Factors Related to the Reversal and Perioperative Outcomes of Defunctioning Ileostomies in Patients Undergoing Rectal Cancer Surgery: A Regression Analysis Model

PURPOSE

Defunctioning ileostomies are often performed during rectal cancer surgery. However, stomas are sometimes associated with complications, while 20-30% of them are never reversed. Additionally, ileostomy closure can have associated morbidity, with rates as high as 45%, with the respective literature evidence being scarce and conflicting. Thus, we evaluated the stoma reversal outcomes and the risk factors for non-closure after rectal cancer surgery.

METHODS

This is a retrospective analysis of a prospectively collected database of all patients who had a defunctioning ileostomy at the time of resection for rectal cancer. All operations were performed by the same surgical team. A multivariable regression model was implemented.

RESULTS

In this study, 129 patients (male: 68.2%, female: 31.8%) were included. Ileostomy formation was associated with a total of 31% complication rate. Eventually 73.6% of the stomas were reversed at a mean time to closure of 26.6 weeks, with a morbidity of 13.7%. Non-reversal of ileostomy was correlated with neoadjuvant CRT (OR: 0.093, 95% CI: 0.012-0.735), anastomotic leakage (OR: 0.107, 95% CI: 0.019-0.610), and lymph node yield (OR: 0.946, 95% CI: 0.897-0.998). Time to reversal was affected by the N status, the LNR, the need for adjuvant chemotherapy, and the histologic grade.

CONCLUSION

In patients with rectal cancer resections, defunctioning stoma closure rate and time to closure were associated with several perioperative and pathological outcomes.

Risk Factors for Radical Rectal Cancer Surgery with a Temporary Stoma Becoming a Permanent Stoma: A Pooling Up Analysis

Purpose: The aim of this study was to find out the potential risk factors for the formation of a permanent stoma (PS) for rectal cancer patients with a temporary stoma (TS) after surgery. Methods: PubMed, Embase, and the Cochrane Library were searched for eligible studies until November 14, 2022. The patients were divided into the PS group and the TS group. Odds ratio (ORs) and 95% confidence intervals (CIs) were pooled up for describing dichotomous variables. Stata SE 16 was performed for data analysis. Results: After pooling up the data, a total of 14 studies involving 14,265 patients were included in this study. The outcomes showed that age (OR = 1.03, 95% CI = 0.96 to 1.10, I2 = 1.42%, P = .00 < .1), surgery type (P = .00 < .1), tumor stage (P = .00 < .1), preoperative chemoradiotherapy (P = .00 < .1), preoperative radiotherapy (P = .01 < .1), neoadjuvant therapy (P = .00 < .1), American Society of Anesthesiologists (ASA) score of ≥3 (P = .00 < .1), anastomotic leakage (P = .01 < .1), local recurrence (P = .00 < .1), and distant recurrence (P = .00 < .1) were associated with the patient with PS. However, sex (P = .15 > .1), previous abdominal surgery (P = .84 > .1), adjuvant chemotherapy (P = .87 > .1), and defunctioning stoma (P = .1) had little association with PS. Conclusion: Patients who were elderly, had advanced tumor stages, had a high ASA score, and underwent neoadjuvant therapy should be informed of the high risk of PS before surgery. Meanwhile, those who underwent rectal cancer surgery with a TS should beware of anastomotic leakage, local recurrences, and distant recurrences, which could increase the risk of PS.

Efficacy and Safety of Preoperative Radiotherapy Versus Chemoradiotherapy in Advanced Rectal Cancer: A Meta-analysis of Randomized Controlled Trials

OBJECTIVE

This meta-analysis was conducted to evaluate the safety and efficacy of preoperative radiotherapy (RT) combined with surgery and preoperative chemoradiotherapy (CRT) combined with surgery for locally advanced rectal cancer.

METHODS

PubMed, EMBASE and Cochrane Library were searched to collect published randomized controlled trials of preoperative radiotherapy or preoperative CRT combined with surgery for the treatment of locally advanced rectal cancer. Studies were screened according to inclusion and exclusion criteria, and quality was evaluated; RevMan 5.3 software was used for meta-analysis.

RESULTS

In total, 7 related studies involving 3100 patients with locally advanced rectal cancer were evaluated. The pathological complete response rate, negative lymph node rate, R0 resection rate, and incidence of grade III/IV adverse reactions were lower in the RT group than in the CRT group. In the absence of postoperative chemotherapy, the 5-year local recurrence rate of RT was higher than that of CRT, but there was no significant difference between the groups among those who underwent postoperative chemotherapy. Moreover, there was no significant difference between the groups with regard to the 5-year survival rate, anal-preserving rate, or incidence of anastomotic leakage.

CONCLUSION

Preoperative CRT is better than preoperative RT for the treatment of advanced rectal cancer, though the adverse reaction rate is higher.

Two-year follow-up results of the use of a fecal diverting device as a substitute for a defunctioning stoma

PURPOSE

Our previously published clinical studies described the short-term outcomes of a newly developed intraluminal fecal diverting device (FDD). FDD was a safe and effective substitute for a defunctioning stoma. However, the long-term efficacy and safety of this device remain unknown. We investigated the long-term outcomes of the use of the FDD as a substitute for a defunctioning stoma.

METHODS

We examined the medical records of patients who participated in our two previous FDD clinical studies. The main outcome was the number of patients with bowel continuity for 2 years after undergoing the FDD procedure or defunctioning stoma creation.

RESULTS

Between May 2015 and July 2018, 85 patients were screened for inclusion in this study. Of those, 27 patients underwent a defunctioning ileostomy after proctectomy. The remaining 58 underwent the FDD procedure after proctectomy. Seventy-two patients (ileostomy group, n = 22; FDD group, n = 50) with a follow-up duration > 24 months were included in this analysis. The mean duration of fecal diversion was significantly shorter (p < 0.001) in the FDD group (3.1 [1.6-6.1] weeks) than in the ileostomy group (16.7 [10.0-31.6] weeks). However, the rate of permanent stoma creation was not statistically different between the two groups (ileostomy and FDD groups, 13.6% [3/22] and 10.0% [5/50], respectively; p = 0.693).

CONCLUSIONS

The FDD procedure is a feasible substitute for a defunctioning stoma after proctectomy. Multicenter large-scaled clinical studies are required to validate our results.

Effects of Neoadjuvant Radiotherapy on Postoperative Complications in Rectal Cancer: A Meta-Analysis

Objective

Neoadjuvant radiotherapy (nRT) is an important treatment approach for rectal cancer. The relationship, however, between nRT and postoperative complications is still controversial. Here, we conducted a meta-analysis to evaluate such concerns.

Methods

The electronic literature from 1983 to 2021 was searched in PubMed, Embase, and Web of Science. Postoperative complications after nRT were included in the meta-analysis. The pooled odds ratio (OR) was calculated by the random-effects model. Statistical analysis was conducted by Review Manager 5.3 and STATA 14.

Results

A total of 23,723 patients from 49 studies were included in the meta-analysis. The pooled results showed that nRT increased the risk of anastomotic leakage (AL) compared to upfront surgery (OR = 1.23; 95% CI, 1.07-1.41; p=0.004). Subgroup analysis suggested that both long-course (OR = 1.20, 95% CI 1.03-1.40; p=0.02) and short-course radiotherapy (OR = 1.25, 95% CI, 1.02-1.53; p=0.04) increased the incidence of AL. In addition, nRT was the main risk factor for wound infection and pelvic abscess. The pooled data in randomized controlled trials, however, indicated that nRT was not associated with AL (OR = 1.01; 95% CI 0.82-1.26; p=0.91).

Conclusions

nRT may increase the risk of AL, wound infection, and pelvic abscess compared to upfront surgery among patients with rectal cancer.

Anus-Preserving Surgery in Advanced Low-Lying Rectal Cancer: A Perspective on Oncological Safety of Intersphincteric Resection

The surgical management of low-lying rectal cancer, within 5 cm from the anal verge (AV), is challenging due to the possibility, or not, to preserve the anus with its sphincter muscles maintaining oncological safety. The standardization of total mesorectal excision, the adoption of neoadjuvant chemoradiotherapy, the implementation of rectal magnetic resonance imaging, and the evolution of mechanical staplers have increased the rate of anus-preserving surgeries. Moreover, extensive anatomy and physiology studies have increased the understanding of the complexity of the deep pelvis. Intersphincteric resection (ISR) was introduced nearly three decades ago as the ultimate anus-preserving surgery. The definition and indication of ISR have changed over time. The adoption of the robotic platform provides excellent perioperative results with no differences in oncological outcomes. Pushing the boundaries of anus-preserving surgeries has risen doubts on oncological safety in order to preserve function. This review critically discusses the oncological safety of ISR by evaluating the anatomical characteristics of the deep pelvis, the clinical indications, the role of distal and circumferential resection margins, the role of the neoadjuvant chemoradiotherapy, the outcomes between surgical approaches (open, laparoscopic, and robotic), the comparison with abdominoperineal resection, the risk factors for oncological outcomes and local recurrence, the patterns of local recurrences after ISR, considerations on functional outcomes after ISR, and learning curve and surgical education on ISR.

[Risk factors associated with non-closure of defunctioning stoma in patients with rectal cancer: univariate and multivariate analysis]

OBJECTIVE

To identify the risk factors associated with non-closure of defunctioning stoma in patients with rectal cancer.

MATERIAL AND METHODS

A retrospective analysis included patients who underwent surgical treatment at the Ryzhikh National Medical Research Centre of Coloproctology for the period from March 2017 to August 2019. Inclusion criterion was anterior or low anterior resection followed by anastomosis and preventive stoma. Univariate and multivariate analysis enrolled 28 factors for identifying the risk factors of non-closure of defunctioning stoma.

RESULTS

There were 246 patients with rectal cancer. Intraoperative fluorescence angiography was applied in 145 cases to assess blood supply within the anastomosis and reduce the risk of anastomotic leakage. According to multivariate analysis, only two factors had significant influence on non-closure of preventive stoma - any grade of anastomotic leakage (OR 6.5; 95% CI 2.2-18.8, p=0.001) and rectal cancer stage IV (OR 7.2; 95% CI 1.9-27.6, p=0.004).

CONCLUSION

According to our data, permanent stoma is observed in 15% of patients.

What is the risk of permanent stoma beyond 5 years after low anterior resection for rectal cancer? A 15-year follow-up of a randomized trial

AIM

Low anterior resection of the rectum for cancer (LAR) entails a risk of symptomatic anastomotic leakage as well as impaired anorectal function, both of which may eventually result in the need for a permanent stoma (PS). The aim was to investigate the incidence of and risk factors for PS beyond 5 years following LAR.

METHODS

Patients undergoing LAR and included in a multicentre trial with randomization to defunctioning stoma or not were followed for a median of 15 years. The reasons for a PS up to 5 years (PS ≤ 5 years) and beyond 5 years (PS > 5 years) were identified and compared. Risk factors for PS were analysed.

RESULTS

Of all patients, 25% (57/232) had a PS. PS ≤ 5 years occurred in 19% (44/232) at a median of 12.5 months and PS > 5 years in 6% (13/232) at a median of 118 months following LAR. The main reason for PS ≤ 5 years was impaired anorectal function in 55% (24/44) and the main reason for PS > 5 years was pelvic sepsis related to the colorectal anastomosis in 46% (6/13). The major risk factor for PS was symptomatic anastomotic leakage, which occurred in 56% (32/57) of patients with PS and 10% (17/175) of patients without PS (P < 0.001).

CONCLUSION

One-fourth of the patients who ended up with a PS had it fashioned beyond 5 years at a median of 10 years following LAR. Symptomatic anastomotic leakage was the major risk factor for PS, and impaired anorectal function was the main overall reason for a PS.

Ultimate Functional Preservation With Intersphincteric Resection for Rectal Cancer

The proximity of the very low rectum rectal cancer to the anal sphincter raises a specific problem: how and until when can we preserve the anal continence without compromising the oncological result of the tumor resection? In this situation, intersphincteric resection (ISR) offers an excellent alternative to abdominoperineal resection (APR), but the selection of patients for this option must be extremely precise. This complex choice justifies the simultaneous consideration of an oncological approach with a functional approach in order to provide a full benefit to the patient. When a circumferential resection margin of at least 1 mm can be performed with a distal resection margin of at least 1 cm with or without preoperative radiotherapy, ISR ensures a safety choice. The oncological results of ISR reported in the literature when performed properly found a 5-year disease-free survival of 80.2% with a local recurrence rate of only 5.8%. In parallel to this oncological evaluation, the expected post-operative functional outcome and the resulting quality of life must be properly assessed pre-operatively, since partial or total resection of the internal sphincter impacts significantly on the functional outcome. Based on data from the literature, this work reports the essential anatomical considerations and then the oncological and functional elements indispensables when an anal continence preservation is evoked for a tumor of the very low rectum. Finally, the precise selection criteria and the major surgical principles are outlined in order to guarantee the safety of this modern choice for the patient.

Population-based study of morbidity risk associated with pathological complete response after chemoradiotherapy for rectal cancer

Background

Neoadjuvant chemoradiotherapy (nCRT) for locally advanced rectal cancer may induce a pathological complete response (pCR) but increase surgical morbidity due to radiation-induced fibrosis. In this study the association between pCR and postoperative surgical morbidity was investigated.

Methods

Patients in the Netherlands with rectal cancer who underwent nCRT followed by total mesorectal excision between 2009 and 2017 were included. Data were stratified into patients who underwent resection with creation of a primary anastomosis and those who had a permanent stoma procedure. The association between pCR and postoperative morbidity was investigated in univariable and multivariable logistic regression analyses.

Results

pCR was observed in 976 (12·2 per cent) of 8003 patients. In 3472 patients who had a primary anastomosis, the presence of pCR was significantly associated with surgical complications (122 of 443 (27·5 per cent) versus 598 of 3029 (19·7 per cent) in those without pCR) and anastomotic leak (35 of 443 (7·9 per cent) versus 173 of 3029 (5·7 per cent) respectively). Multivariable analysis also showed associations between pCR and surgical complications (adjusted odds ratio (OR) 1·53, 95 per cent c.i. 1·22 to 1·92) and pCR and anastomotic leak (adjusted OR 1·41, 1·03 to 2·05). Of 4531 patients with a permanent stoma, surgical complications were observed in 120 (22·5 per cent) of 533 patients with a pCR, compared with 798 (20·0 per cent) of 3998 patients with no pCR (adjusted OR 1·17, 0·94 to 1·46).

Conclusion

Patients with a pCR in whom an anastomosis was created were at increased risk of developing an anastomotic leak.

Clinical outcomes of preoperative chemoradiotherapy in octogenarian with locally advanced rectal cancer

The number of elderly patients who receive surgical treatment for rectal cancer has gradually increased with aging of the population. In recent years, preoperative chemoradiotherapy, followed by surgical treatment, has been widely used for treating patients with locally advanced rectal adenocarcinoma. The aim of the present study was to evaluate if preoperative chemoradiotherapy is efficacious and safe for the treatment of rectal cancer in patients older than 80 years. A total of 293 patients with rectal cancer, who received preoperative chemoradiotherapy from 2007 to 2017, were studied. Comorbidities and the short- and long-term outcomes in elderly patients (aged ≥80 years old) were investigated and compared to younger patients. The elderly group comprised of 17 patients (5.8%). Pulmonary disease was the most common comorbidity (23.5%). No significant difference between the two groups regarding the rate of completeness of chemoradiotherapy was detected (P=0.26). Curative resection was performed in 14 patients in the elderly group and 252 patients in the younger group. Among 7 patients from both groups who could not receive curative resection due to their poor general condition, 4 patients had decreased lower respiratory function due to pneumonia (3 patients) or chronic obstructive pulmonary disease (1 patient). Morbidity and mortality rates were similar in elderly and younger groups (35.7% vs. 27.0%, 0% vs. 0%, respectively; P=0.54, P=1.00). No significant difference was found regarding recurrence between the two groups (P=1.00). To conclude, preoperative chemoradiotherapy in elderly patients with rectal cancer is safe and well tolerated.

Sphincter-Preserving Surgery for Low Rectal Cancers: Incidence and Risk Factors for Permanent Stoma

BACKGROUND

Advances in surgical techniques and paradigm changes in rectal cancer treatment have led to a drastic decline in the abdominoperineal resection rate, and sphincter-preserving operation is possible in distal rectal cancer.

OBJECTIVE

The aim of this study is to evaluate the long-term incidence of permanent stoma after sphincter-preserving surgery for low rectal cancer and its corresponding risk factors.

METHOD

From 2000 to 2014, patients who underwent sphincter-preserving low anterior resection for low rectal cancer (within 5 cm from the anal verge) were included. The occurrence of permanent stoma over time and its risk factors were investigated by using a Cox proportional hazards regression model.

RESULTS

This study included 194 patients who underwent ultra-low anterior resection for distal rectal cancer, and the median follow-up period was 77 months for the surviving patients. Forty-six (23.7%) patients required a permanent stoma eventfully. Anastomotic-related complications and disease progression were the main reasons for permanent stoma. Clinical anastomotic leakage (HR 5.72; 95% CI 2.31-14.12; p < 0.001) and neoadjuvant chemoradiation (HR 2.34; 95% CI 1.12-4.90; p = 0.024) were predictors for permanent primary stoma. Local recurrence (HR 16.09; 95% CI 5.88-44.03; p < 0.001) and T4 disease (HR 11.28; 95% CI 2.99-42.49; p < 0.001) were predictors for permanent secondary stoma. The 5- and 10-year cumulative incidence for permanent stoma was 24.1 and 28.0%, respectively.

CONCLUSION

Advanced disease, prior chemoradiation, anastomotic leakage and local recurrence predispose patients to permanent stoma should be taken into consideration when contemplating sphincter-preserving surgery.

Use of a nomogram to predict the closure rate of diverting ileostomy after low anterior resection: A retrospective cohort study

INTRODUCTION

Although temporary ileostomy is widely used to prevent complications due to anastomotic leakage after middle and low rectal cancer surgery, some patients fail to achieve stoma closure after primary surgery. The aim of this study was to identify the risk factors for permanent stoma following low anterior resection (LAR) or intersphincteric resection (ISR) with a temporary ileostomy for rectal cancer, while focusing on the time course, to develop a nomogram that can predict the rate of unreversed ileostomy 1 year after initial surgery.

METHOD

A total of 212 consecutive rectal cancer patients who underwent LAR or ISR with or without a temporary stoma between 2012 and 2015 at the University of Tokyo Hospital were retrospectively reviewed. Data analyses were performed using JMP Pro 11.0 and R 3.0.1 with rms and Hmisc packages to identify the risk factors for diverting ileostomy resulting in un-reversed stoma, and to develop a nomogram using these factors.

RESULTS

Among 212 patients, diverting ileostomy and colostomy were performed in 116 and 11 patients, respectively, and a stoma was not created in 85 patients. Among the ileostomy cases, 94 underwent stoma reversal, and the median interval from initial surgery to stoma closure was 6.9 months. Three patients eventually underwent stoma re-creation, and hence, 25 patients had permanent stoma. The following variables were correlated with the stoma non-reversal rate and were included in the nomogram: depth of invasion (p = 0.02), presence of metastatic organs (p = 0.07), and preoperative chemoradiotherapy (p = 0.03). The nomogram C-index was 0.612, indicating moderate predictive ability.

CONCLUSIONS

The most common factors preventing stoma closure included distant metastasis or rectal cancer recurrence. The nomogram developed in the present study can help identify rectal cancer patients with high risk of stoma non-reversal.

Reduced pelvic field sparing anastomosis for postoperative radiotherapy in selected patients with mid-upper rectal cancer

The aim of this study was to report the clinical results of reduced pelvic field radiotherapy (RT), excluding the anastomotic site, after total mesorectal excision in selected patients with rectal cancer. Between 2011 and 2014, 99 patients underwent upfront surgery for clinically less-advanced tumors but were finally diagnosed as pT3/N+. Among them, 50 patients with mid-upper rectal cancer who received postoperative RT with a reduced pelvic field were included in this retrospective review. This group was composed of patients with high seated tumors, complete resection with a clear circumferential resection margin, and no complication during surgery. We investigated treatment outcomes, toxicity and the effect of RT-field reduction on organs-at risk in 5 randomly selected patients. During the median follow-up period of 42 months (range: 15-59 months), tumors recurred in 9 patients (18%). The 3-year overall and disease-free survival were 98% and 81%, respectively. Distant metastasis was the dominant failure pattern (n = 8, 16%), while no recurrences occurred at or near anastomotic sites. No anastomotic complications were found on pelvic examination, images and/or colonoscopy. Reported acute and late RT-related toxicities were mostly mild to moderate, with only small numbers of Grade 3 toxicities. None of the patients developed Grade 4-5 acute or late toxicity. With a caudally reduced field, 64% reduction in absolute anastomotic exposure at the maximum dose was achieved compared with the traditional whole-pelvic field (P = 0.008). The reduced pelvic field RT was able to minimize late anastomotic complication without increasing its recurrence in selected patients with mid-upper rectal cancer in the postoperative setting.

The Role of Temporary Fecal Diversion

The use of temporary fecal diversion is of great importance to tenuous anastomosis, immunosuppressed patient, or actively infected patient. Its use protects newly constructed intestinal anastomoses from being the culprit of pelvic sepsis or systemic illness. Thus, potential morbidity and mortality can be averted. However, its appropriate or optimal use is often debated. We herein discuss the evidence for when to best use a diverting stoma for colorectal, coloanal, and ileoanal anastomoses. We also discuss the importance of considering a temporary diverting stoma in the setting of high-dose immunosuppression (e.g., transplant patients or inflammatory bowel disease), active infection, or upon creation of ileal pouch-anal anastomosis. Lastly, we discuss the advantages and disadvantages of a loop ileostomy versus colostomy for temporary diversion of fecal contents.

Intersphincteric resection for very low rectal cancer: A review of the updated literature

Intersphincteric resection (ISR) has rapidly increased worldwide including laparoscopic surgery. However, there are some concerns for the definition of ISR, surgical technique, oncological outcome, anal function, and quality of life (QoL). The aim of the present study is to evaluate those issues. A review of this surgical technique was carried out by searching English language literature of the PubMed online database and appropriate articles were identified. With regard to open‐ISR, the morbidity rate ranged from 7.5% to 38.3%, with lower mortality rates. Local recurrence rates varied widely from 0% to 22.7%, with a mean follow‐up duration of 40–94 months. Disease‐free and overall 5‐year survival rates were 68–86% and 76–97%, respectively. Those outcomes were equivalent to laparoscopic‐ISR. Surgical and oncological outcomes of ISR were generally acceptable. However, accurate evaluation of anal function and QoL was difficult because of a lack of standard assessment of various patient‐related factors. The surgical and oncological outcomes after ISR seem to be acceptable. The ISR technique seems to be valid as an alternative to abdominoperineal resection in selected patients with a very low rectal cancer. However, both necessity for ISR and expectations of QoL impairment as a result of functional disorder should be fully discussed with patients before surgery.

Pathologic response grade after long-course neoadjuvant chemoradiation does not influence morbidity in locally advanced mid-low rectal cancer resected by laparoscopy

PURPOSE

Patients with locally advanced rectal cancer and pathologic complete response to neoadjuvant chemoradiation therapy have lower rates of recurrence compared to those who do not. However, the influences of the pathologic response on surgical complications and survival remain unclear. This study aimed to investigate the influence of neoadjuvant therapy for rectal cancer on postoperative morbidity and long-term survival.

METHODS

This was a comparative study of consecutive patients who underwent laparoscopic total mesorectal excision for rectal cancer in two European tertiary hospitals between 2004 and 2014. Patients with and without pathologic complete responses were compared in terms of postoperative morbidity, mortality, and survival.

RESULTS

Fifty patients with complete response (ypT0N0) were compared with 141 patients who exhibited non-complete response. No group differences were observed in the postoperative mortality or morbidity rates. The median follow-up time was 57 months (range 1-121). Over this period, 11 (5.8 %) patients, all of whom were in the non-complete response group, exhibited local recurrence. The 5-year overall survival and disease-free survival were significantly better in the complete response group, 92.5 vs. 75.3 % (p = 0.004) and 89 vs. 73.4 % (p = 0.002), respectively.

CONCLUSIONS

Postoperative complication rate after laparoscopic total mesorectal excision is not associated with the pathologic response grade to neoadjuvant chemoradiation therapy.

Does neoadjuvant therapy increase the incidence of anastomotic leakage after anterior resection for mid and low rectal cancer? A systematic review and meta-analysis

AIM

The aim was to evaluate the association of neoadjuvant therapy with increases in the incidence of anastomotic leakage (AL) after middle and low rectal anterior resection.

METHOD

The electronic databases of PubMed, Web of Science, Scopus and Ovid were searched between 1980 and 2015. The random effects model was used to model the pooled data to determine the odds ratio with 95% confidence interval. Heterogeneity was evaluated using the Q test and I² statistics. Subgroup, sensitivity and meta-regression analysis was conducted to explore heterogeneity.

RESULTS

Neoadjuvant therapy was not shown to increase the incidence of postoperative AL as demonstrated by an OR of 1.16 [95% CI 0.99-1.36; P = 0.07 (random effects model)]. The subgroup analysis of neoadjuvant radiotherapy using the random effects model suggested that it did not increase the rate of postoperative AL (OR = 1.24, 95% CI 0.97-1.58; P = 0.08). The subgroup analysis of neoadjuvant chemoradiotherapy indicated that the rate of postoperative AL again did not increase with an OR = 1.06 [95% CI 0.86-1.30; P = 0.59 (random effects model)]. The interval to surgery after neoadjuvant therapy and preoperative radiotherapy (short or long course) was not associated with an increased incidence of postoperative AL.

CONCLUSION

Neoadjuvant therapy does not appear to increase the incidence of postoperative AL after anterior resection for mid and low rectal cancer. In addition, neither the interval to surgery after neoadjuvant therapy nor the radiotherapy regimen increases the rate of postoperative AL.

Risk factors of permanent stomas in patients with rectal cancer after low anterior resection with temporary stomas

PURPOSE

The aim of this study was to identify risk factors influencing permanent stomas after low anterior resection with temporary stomas for rectal cancer.

MATERIALS AND METHODS

A total of 2528 consecutive rectal cancer patients who had undergone low anterior resection were retrospectively reviewed. Risk factors for permanent stomas were evaluated among these patients.

RESULTS

Among 2528 cases of rectal cancer, a total of 231 patients had a temporary diverting stoma. Among these cases, 217 (93.9%) received a stoma reversal. The median period between primary surgery and stoma reversal was 7.5 months. The temporary and permanent stoma groups consisted of 203 and 28 patients, respectively. Multivariate analysis showed that independent risk factors for permanent stomas were anastomotic-related complications (p=0.001) and local recurrence (p=0.001). The 5-year overall survival for the temporary and permanent stoma groups were 87.0% and 70.5%, respectively (p<0.001).

CONCLUSION

Rectal cancer patients who have temporary stomas after low anterior resection with local recurrence and anastomotic-related complications may be at increased risk for permanent stoma.

Does pathologic response of rectal cancer influence postoperative morbidity after neoadjuvant radiochemotherapy and total mesorectal excision?

BACKGROUND

A pathologic complete response (pCR) can be observed in up to 25% of patients after preoperative chemoradiotherapy for rectal cancer and is associated with an improved long-term prognosis. However, few data are available regarding the effect of pCR on postoperative morbidity. This study aimed to assess the impact of the pCR on postoperative outcomes after laparoscopic total mesorectal excision (TME).

METHODS

A prospectively maintained database (2006-2011) was reviewed for all consecutive patients (n = 143) undergoing laparoscopic TME for mid or low rectal cancer after neoadjuvant chemoradiotherapy. Postoperative data were compared for pCR-group and non-pCR-group. A pCR was defined as the absence of gross and microscopic tumor in the specimen, irrespective of the nodal status (ypT0).

RESULTS

Thirty-three patients (23%) had a pCR. Median operating time was greatly shorter in the pCR-group (230 minutes, 180-360), compared with the non-pCR-group (240 minutes, 130-420, P = .02). Lymph node involvement was noted for 12% of the patients in the pCR-group and 33% of the patients in the non-pCR-group (P = .91). Clavien Dindo grade 3 and 4 complications (6% vs 22%, P = .04), infection related morbidity (47% vs 76%, P = .04), and clinical anastomotic leakage rates (9% vs 29%, P = .02) were lesser in the pCR group compared with the non-pCR group. Mean duration of hospital stay was lesser in the pCR-group (9 vs 12 days, P = .01).

CONCLUSION

This study showed that Clavien Dindo grade 3 and 4 complications, including anastomosis leakage, and infection related complications rates were lesser in patients with pathologic complete response after RCT and laparoscopic TME for rectal cancer.

Cumulative incidence of permanent stoma after sphincter preserving low anterior resection of mid and low rectal cancer

BACKGROUND

Changes in the treatment of rectal cancer during the past decades have led to an increase in sphincter preservation with a consecutive decline in abdominoperineal resection rates.

OBJECTIVE

The aim of this study was to analyze the cumulative incidence of permanent stoma in patients undergoing sphincter-preserving resection of mid and low rectal cancer.

DESIGN

This study is a retrospective analysis of prospectively collected data.

SETTINGS

This study was conducted at a tertiary referral cancer hospital.

PATIENTS

From 2003 to 2010, 125 patients with primary mid and low rectal cancer who underwent sphincter-preserving low anterior resection were included.

MAIN OUTCOME MEASURES

The occurrence of a permanent stoma over time was investigated by using a Cox proportional hazards regression model and competing-risk models, with death as a competing risk. The risk factors were assessed by computing HRs and a Cox proportional hazards regression.

RESULTS

After a median follow-up time of 61 months (range, 22-113), 15 of 125 patients ended up with a permanent stoma, accounting for a 5-year cumulative incidence of 6% (95% CI, 4%-11%). The reasons for obtaining a permanent stoma were anastomotic leakage (60%, 9/15), intractable fecal incontinence (27%, 4/15), and local recurrence (13%, 2/15). The Cox proportional hazards regression identified anastomotic leakage (HR, 6.10; 95% CI, 2.23-16.71; p = 0.0004) and coloanal anastomosis (HR, 4.31; 95% CI, 1.49-12.47; p = 0.007) as statistically significant risk factors.

LIMITATIONS

Because of the small number of events in this sample, further investigations with a larger number of patients are required. Fecal incontinence was assessed by patient self-reported data without the use of a validated score.

CONCLUSION

The 5-year cumulative incidence of a permanent stoma was 6%. Anastomotic leakage and coloanal anastomosis were identified as risk factors. These details should be considered before sphincter-preserving surgery.

The Role of Diverting Stoma After an Ultra-low Anterior Resection for Rectal Cancer

Purpose

A diverting stoma is known to reduce the consequences of distal anastomotic failure following colorectal surgery. The aim of this study was to evaluate the efficacy of a diverting stoma after an ultra-low anterior resection (uLAR) for rectal cancer.

Methods

Between 2000 and 2007, 836 patients who underwent an uLAR were divided into two groups, depending on the fecal diversion: 246 received fecal diversion, and 590 had no diversion. Patient- and disease-related variables were compared between the two groups.

Results

Thirty-two of the 836 patients (3.8%) had immediate anastomosis-related complications and required reoperation. Anastomosis leakage comprised 72% of the complications (23/32). The overall immediate complication rate was significantly lower in patients with a diverting stoma (0.8%, 2/246) compared to those without a diverting stoma (5.1%, 30/590; P = 0.005). The fecal diversion group had lower tumor location, lower anastomosis level, and more preoperative chemo-radiation therapy (P < 0.001). In total, 12% of patients in the diverting stoma group had complications either in making or reversing the stoma (30/246).

Conclusion

The diverting stoma decreased the rate of immediate anastomosis-related complications. However, the rate of complications associated with the diverting stoma was non-negligible, so strict criteria should be applied when deciding whether to use a diverting stoma.

Intersphincteric resection for very low rectal cancer: a systematic review

Radical surgical treatment for very low rectal cancer near the anus has generally involved abdominoperineal resection. Various sphincter-saving operations have been developed for such tumors to optimize the patients' postoperative quality of life. Current protocols focus on intersphincteric resection (ISR), which differs from conventional hand-sewn coloanal anastomosis (CAA) after low anterior resection. However, the efficacy of ISR remains unclear. The surgical, oncologic, and functional outcomes after intersphincteric resection (ISR) were reviewed. This review of the current literature was conducted by searching the PubMed online database. Articles focusing specifically on conventional hand-sewn CAA were excluded from this study. The mean mortality rate is <2 %, and the mean morbidity rate ranges from 7.7 to 38.3 %. The mean local recurrence rate varies widely from 0 to 22.7 %, with a mean follow-up duration of 40-94 months. The mean disease-free and overall 5-year survival rates are 69-86 and 79-97 months, respectively. Functional outcomes are generally acceptable, but accurate evaluation is extremely difficult due to the absence of unified appraisal methods. ISR appears surgically, oncologically and functionally acceptable. However, more experience and better understanding of the oncology, anal physiology, and pelvic anatomy are necessary to achieve successful outcomes without complications, and to improve patient survival.

External coloanal anastomosis without covering stoma in low-lying rectal cancer

The aim of this study was to evaluate the safety and functional outcome of external coloanal anastomosis without covering stoma in treating low-lying rectal cancer. All patients undergoing the coloanal anastomosis for low lying rectal carcer in the Department of General Surgery, Minia University Hospital, between May 2006 and May 2009 were included. Seventy two patients underwent coloanal anastomosis, and follow up was available for all patients. Mean follow up period was 12.6 ± 4.7 months. Postoperatively, fecal continence was normal in 84.7% of patients. Postoperative complications included anastomotic fistula in 3 patients (4.2%) and anastomotic stenosis in 6 patients (8.3%). There was no effect of pre or postoperative adjuvant therapy on the procedure outcome. There was no local recurrence during follow up period. Three patients died at the end of follow up period due to distant metastasis. In treatment of low-lying rectal cancer, abdominoperineal resection should be avoided if coloanal anastomosis provides similar control of the disease as it is safe and has good functional results and acceptable complication rate.

Permanent stoma after low anterior resection for rectal cancer

BACKGROUND AND OBJECTIVES

A low anterior resection procedure for removing a rectal tumor aims to preserve the sphincter and avoid a permanent stoma. Permanent stomas are primarily necessary in cases of poor anorectal function and local recurrence. The aim of this study was to clarify whether anastomosis-related complications and local recurrence influenced the rate of permanent stomas in a long-term follow-up.

METHODS

Of 1032 consecutive patients with rectal cancer, 397 were treated by low anterior resection (R0 and R1 resections) between 1985 and 2007 at the Department of General and Abdominal Surgery of the University Hospital, Mainz (Germany). All patient data were collected prospectively. A retrospective, multivariate analysis was conducted to determine factors that influenced the occurrence of delayed and nonreversal of defunctioning stoma, the rate of repeat stoma after closure, and the need for a permanent stoma in patients whose stomas were not initially defunctioning.

RESULTS

A defunctioning stoma was created in 292 of 397 patients (74%); 12% of stomas were not reversible (33/279 that survived the operation >90 d); 11% (28/246) required a repeat stoma after stoma closure; 10% (10/105) of patients whose stomas were not initially defunctioning received a late permanent stoma. The overall rate of a permanent stoma was 18%. The main reasons for a permanent stoma were anastomosis-related complications and local recurrence. Risk factors for anastomosis-related complication were male gender, low tumor site, and tumor stage. Despite a significant reduction in local recurrence rates from 1997 to 2007, the rate of creating a permanent stoma did not change.

CONCLUSIONS

The possibility of a permanent stoma should be considered when planning surgery for treating rectal cancer. It might be preferable in older patients, in poor condition and with more advanced rectal cancers, to consider an abdominoperineal resection or Hartmann procedure instead of a low anterior resection.

Complications after sphincter-saving resection in rectal cancer patients according to whether chemoradiotherapy is performed before or after surgery

PURPOSE

The aim of the present study was to compare the influence of preoperative chemoradiotherapy (CRT) with postoperative CRT on the incidence and types of postoperative complications in rectal cancer patients who underwent sphincter-saving resection.

PATIENTS AND METHODS

We reviewed 285 patients who received preoperative CRT and 418 patients who received postoperative CRT between January 2000 and December 2006.

RESULTS

There was no between-group difference in age, gender, or cancer stage. In the pre-CRT group, the mean level of anastomosis from the anal verge was lower (3.5 +/- 1.4 cm vs. 4.3 +/- 1.7 cm, p < 0.001) and the rate of T4 lesion and temporary diverting ileostomy was higher than in the post-CRT group. Delayed anastomotic leakage and rectovaginal fistulae developed more frequently in the pre-CRT group than in the post-CRT group (3.9% vs. 1.2%, p = 0.020, 6.5% vs. 1.3%, p = 0.027, respectively). Small bowel obstruction (arising from radiation enteritis) requiring surgical intervention was more frequent in the post-CRT group (0% in the pre-CRT group vs. 1.4% in the post-CRT group, p = 0.042). Multivariate analysis identified preoperative CRT as an independent risk factor for fistulous complications (delayed anastomotic leakage, rectovaginal fistula, rectovesical fistula), and postoperative CRT as a risk factor for obstructive complications (anastomotic stricture, small bowel obstruction). The stoma-free rates were significantly lower in the pre-CRT group than in the post-CRT group (5-year stoma-free rates: 92.8% vs. 97.0%, p = 0.008).

CONCLUSION

The overall postoperative complication rates were similar between the pre-CRT and the Post-CRT groups. However, the pattern of postoperative complications seen after sphincter- saving resection differed with reference to the timing of CRT.

Acellular dermal matrix seeded with autologous fibroblasts improves wound breaking strength in a rodent soft tissue damage model in neoadjuvant settings

Soft tissue defects following resectional surgery or trauma often result in deadspaces and require free or pedicled flaps. A programmed formation of filling tissue with enhanced biomechanical properties could be helpful. This study examined the effects on wound healing of acellular dermal matrix (ADM) seeded with autologous fibroblasts in a standardized rodent model. As pre- or postoperative radiotherapy is standard in many treatments of malignancies, we also investigated the effects of additional radiotherapy. Fischer rats were randomised and received a standardized unilateral soft tissue defect at the buttock. The defect was filled with ADM+fibroblasts or ADM alone. Controls received no filling. Either no radiation, adjuvant (postoperative) or neoadjuvant (preoperative) radiation was applied to the defect site. Six weeks later the defect volume was measured by MR-tomography. Wound breaking strength was examined by tensiometry according to German Industrial Standards. Filling of the defect side was significantly larger in ADM and ADM+fibroblast treated groups compared to the control group in all settings. Wound breaking strength in the unimodal setting was significantly improved in the ADM+fibroblasts group compared to the ADM group. In the neoadjuvant setting there was no significant difference between control and ADM group. However, the ADM+fibroblasts groups showed a significantly increased wound breaking strength compared to the control and the ADM-alone group. Seeded or unseeded ADM is able to fill deadspace in this rodent model in all settings. Implanting non-irradiated, vital, proliferating autologous fibroblasts on ADM results in significantly increased wound breaking strength.