A prospective study on radical and nerve-preserving surgery for rectal cancer in the Netherlands

The erectile and ejaculatory implications of the surgical management of rectal cancer

Colorectal cancer is a significant cause of cancer-related deaths worldwide. Although advances in surgical technology and technique have decreased mortality rates, surviving patients often experience sexual dysfunction as a common complication. The development of the lower anterior resection has greatly decreased the use of the radical abdominoperineal resection surgery, but even the less radical surgery can result in sexual dysfunction, including erectile and ejaculatory dysfunction. Improving the knowledge of the underlying causes of sexual dysfunction in this context and developing effective strategies for preventing and treating these adverse effects are essential to improving the quality of life for postoperative rectal cancer patients. This article aims to provide a comprehensive evaluation of erectile and ejaculatory dysfunction in postoperative rectal cancer patients, including their pathophysiology and time course and strategies for prevention and treatment.

Implantation of skin-derived precursor Schwann cells improves erectile function in a bilateral cavernous nerve injury rat model

BACKGROUND

This study was conducted to investigate the therapeutic potential of the skin-derived precursor Schwann cells for the treatment of erectile dysfunction in a rat model of bilateral cavernous nerve injury.

RESULTS

The skin-derived precursor Schwann cells-treatment significantly restored erectile functions, accelerated the recovery of endothelial and smooth muscle tissues in the penis, and promoted nerve repair. The expression of p-Smad2/3 decreased after the treatment, which indicated significantly reduced fibrosis in the corpus cavernosum.

CONCLUSIONS

Implantation of skin-derived precursor Schwann cells is an effective therapeutic strategy for treating erectile dysfunction induced by bilateral cavernous nerve injury.

Deep-learning-based semantic segmentation of autonomic nerves from laparoscopic images of colorectal surgery: an experimental pilot study

BACKGROUND

The preservation of autonomic nerves is the most important factor in maintaining genitourinary function in colorectal surgery; however, these nerves are not clearly recognisable, and their identification is strongly affected by the surgical ability. Therefore, this study aimed to develop a deep learning model for the semantic segmentation of autonomic nerves during laparoscopic colorectal surgery and to experimentally verify the model through intraoperative use and pathological examination.

MATERIALS AND METHODS

The annotation data set comprised videos of laparoscopic colorectal surgery. The images of the hypogastric nerve (HGN) and superior hypogastric plexus (SHP) were manually annotated under a surgeon's supervision. The Dice coefficient was used to quantify the model performance after five-fold cross-validation. The model was used in actual surgeries to compare the recognition timing of the model with that of surgeons, and pathological examination was performed to confirm whether the samples labelled by the model from the colorectal branches of the HGN and SHP were nerves.

RESULTS

The data set comprised 12 978 video frames of the HGN from 245 videos and 5198 frames of the SHP from 44 videos. The mean (±SD) Dice coefficients of the HGN and SHP were 0.56 (±0.03) and 0.49 (±0.07), respectively. The proposed model was used in 12 surgeries, and it recognised the right HGN earlier than the surgeons did in 50.0% of the cases, the left HGN earlier in 41.7% of the cases and the SHP earlier in 50.0% of the cases. Pathological examination confirmed that all 11 samples were nerve tissue.

CONCLUSION

An approach for the deep-learning-based semantic segmentation of autonomic nerves was developed and experimentally validated. This model may facilitate intraoperative recognition during laparoscopic colorectal surgery.

Protective effect of laparoscopic functional total mesorectal excision on urinary and sexual functions in male patients with mid-low rectal cancer

BACKGROUND

Urinary and sexual dysfunctions are among the most common complications in rectal cancer surgery. This study aimed to investigate the protective effect of laparoscopic functional total mesorectum excision (TME) on urinary and sexual functions in male patients.

METHODS

A total of 248 male patients with mid-low rectal cancer were recruited in this study between February 2017 and July 2020. To overcome selection bias, we performed a 1:1 match using six variables, including age, BMI, ASA score, tumor distance, clinical T stage, and tumor size. The urinary function was assessed by the International Prostate Symptom Score (IPSS), sexual function was assessed by a 5-item version of the International Index of Erectile Function (IIEF-5) and ejaculation grading at postoperative 3 and 12 months.

RESULTS

79 patients received functional TME surgery (FTME group), and 169 patients received routine TME surgery (RTME group). After the propensity score, 79 pairs were balanced and analyzed. Patients in the FTME group showed a lower IPSS score and higher IIEF-5 score than patients in the RTME group at postoperative 3 and 12 months. The incidence of ejaculation dysfunction for patients in the FTME group was lower than patients in the RTME group at postoperative 3 and 12 months.

CONCLUSION

Laparoscopic functional total mesorectal excision was beneficial to faster recovery of urinary and sexual function for patients with rectal cancer, and it could be used as a superior surgical technique for pelvic autonomic nerve preservation in mid-low rectal cancer.

Functional results after mesorectal excision for rectal cancer: comparative study among surgical approaches

BACKGROUND

We analyzed the evolution of genitourinary dysfunctions in patients undergoing surgical treatment for rectal cancer, and compared open surgery, laparoscopy, robotic and TaTME.

METHODS

Functional outcomes were evaluate using standardized questionnaires, compiled at the start of treatment, after the end of Radiotherapy, at 1 and 6 months after surgery.

RESULTS

In 72 patients 37.5% had low, 27.8% middle, and 34.7% high rectal cancers. Open technique was performed in 25% of cases, while 29.2% underwent laparoscopy, 20.8% TaTME and 25% robotic. We noted a deterioration in urogenital function: surgical technique can influence the result both in urinary and male sexual function but not ejaculation. Robotics and laparoscopy bring better outcomes than open surgery and TaTME. Female sexuality worsening seems not influenced by the technique. In general age, stage, complications and anastomotic leakage appear to be predictive factors for functional dysfunctions. As reported in literature rectal cancer treatment leads to urogenital worsening: this seems to be progressive in male sexuality only, while female one and urinary function show a slight improvement in the first months, although a full recovery possibility is discussed. Is also reported how robotic and laparoscopy have a lower functional impact. TaTME has gained consensus thank to the excellent oncological and function outcomes, but in our study leads to worse results.

CONCLUSIONS

Mini-invasive techniques guarantee the same oncological result than more invasive ones, but with better functional outcomes and tolerability; robotic surgery seems to be slight superior than laparoscopy, but with longer operative time.

Acute urinary retention rates following early removal or no placement in colon and rectal surgery: a single-center analysis

BACKGROUND

The adequate duration of urinary drainage following colorectal surgery remains debated. The purpose of this study was to compare acute urinary retention (AUR) rates among various durations of urinary catheterization following colon and rectal surgery.

METHODS

We conducted a retrospective analysis of patients undergoing elective colorectal resection enrolled in the Enhanced Recovery After Surgery (ERAS) protocol from 2018 to 2019. Patients were placed into four groups: no catheter placement (NC), catheter removed immediately after surgery (CRAS), removal less than 24 h (CR < 24), and removal greater than 24 h (CR > 24). Our primary endpoint was the rate of AUR in each group. Secondary endpoints included hospital length of stay and urinary tract infections (UTI). A multivariate logistic regression analysis was done to predict AUR.

RESULTS

A total 641 patients were included in this study. 27 patients (4.2%) had NC with an AUR rate of 3.7%. 249 patients (38.8%) had CRAS with an AUR rate of 6.8%. 214 patients (33.4%) had CR < 24 with an AUR rate of 4.2%. 151 patients (23.6%) had CR > 24 with an AUR rate of 2.6%. There was no significant difference in AUR among the groups (p = 0.264). In our multivariant logistic regression, pelvic surgery was an independent risk factor for AUR (p = 0.008). There was a statistically significant higher hospital length of stay (p = 0.001) and rate of UTIs (p = 0.017) in patients with prolonged catheterization.

CONCLUSION

Deferral or early removal of urinary catheters is safe and feasible following colorectal surgery without a significant increase in AUR. Avoiding prolonged indwelling urinary catheterization may decrease associated complications such as UTI and hospital length of stay.

Prospective study of sexual function and analysis of risk factors after rectal cancer surgery

AIM

The aim of this study was to assess the evolution of sexual function over time after rectal cancer surgery and to identify risk factors that may have an impact on the deterioration of postoperative function.

METHOD

This was a prospective cohort study of sexual function after rectal cancer surgery using the International Index of Erectile Function (IIEF) and Female Sexual Function Index (FSFI) preoperatively and at 6 and 12 months after surgery. Predictive factors of worsening were identified by univariate and multivariate analysis.

RESULTS

One hundred and one patients were included (56 men and 45 women). In men, the average IIEF showed decreased erectile function and intercourse satisfaction at 6 months (respectively 21.58 ± 7.18 to 16.60 ± 7.96, p = 0.002 and 10.87 ± 2.94, to 8.09 ± 4.45, p = 0.002) with recovery at 1 year. As a percentage, erectile dysfunction increased from the preoperative value to 6 months (64.5% vs 87.1%, p = 0.022) and was observed in 72% at 1 year. Patients with moderate to severe dysfunction increased from 22% preoperatively to 58% (p = 0.009) at 6 months and 44% at 1 year (p < 0.0001). Neoadjuvant chemoradiotherapy (OR 5.4, 95% CI 0.9-29.6; p = 0.041) and erectile worsening at 6 months (OR 20, 95% CI 1.6-238; p = 0.004) were independent factors for worse function at 6 or 12 months, respectively. No significant worsening of the FSFI was found, although there was an improvement in lubrication and orgasm.

CONCLUSION

Temporary deterioration of erectile function in men is common at 6 months after surgery and chemoradiotherapy is the only predictive factor. Furthermore, patients who remain dysfunctional show an increase in the severity of symptoms in relation to the preoperative period.

Prospective study of urinary function and analysis of risk factors after rectal cancer surgery

BACKGROUND

Alterations in urinary function are complications of rectal cancer surgery. The aim of this study was to prospectively analyze the changes in urinary function in patients operated on for rectal cancer, and to identify risk factors that may have an impact on the deterioration of postoperative urinary function.

METHODS

A prospective study of urinary function in rectal cancer patients who had elective oncological resection with curative intention at the Arnau de Vilanova Hospital in Valencia, Spain, from January 2017 to March 2019. The evaluation of urinary function was performed using the International Prostate Symptom Score (IPSS) preoperatively, at 6 and 12 months after surgery. Predictive factors of urinary dysfunction were identified by univariate and multivariate analysis.

RESULTS

Ninety-four patients were enrolled in the study. Eighty-seven of them completed all the follow-up assessments (48 men and 39 women, mean age 65.74 ± 10.95 years,). The mean IPSS was 7.96 ± 7.59 preoperatively, 9.01 ± 6.81 at 6 months, and 8.63 ± 5.59 at 12 months, without statistically significant differences. There were no differences in IPSS between males and females. Preoperative urinary dysfunction was 39% and at 12 months, a deterioration occurred in 23 patients (26.4%). IPSS analysis of symptoms showed a statistically significant worsening of nocturia at 6 months (p = 0.002) and 1 year after surgery (p = 0.037) in women. American Society of Anesthesiologists (ASA) class (OR: 11, [95% CI2.4-53]; p = 0.010), surgical difficulty (OR: 4.5, [95% CI 1-19]; p = 0.027) and anastomotic leakage (OR: 14, [95% CI 1.6-117]; p = 0.010), were identified as independent risk factors for deterioration of urinary function after surgery.

CONCLUSIONS

Our study showed worsening urinary dysfunction after rectal cancer surgery in 26.4% of the patients. However, there were no statistically significant differences in mean IPSS scores at the three assessment times (preoperatively, 6 months, 12 months). ASA class, surgical difficulty, and anastomotic leakage may predict postoperative deterioration.

Management of voiding dysfunction associated with pelvic malignancies

Voiding dysfunction is common after surgical and radiation treatments in patients diagnosed with non-urological pelvic malignancies. Presentation might vary with lower urinary tract symptoms and/or overactive bladder, urinary retention, or incontinence. We reviewed the most recent literature with the aim of describing various types of urinary dysfunction that manifest after radical treatments for non-urological pelvic malignancies. Radical surgical or radiation treatment adversely affect other adjacent pelvic organ function, including viscera, pelvic musculature and the peripheral nervous system. This results in direct organ and indirect functional damage to the genitourinary tract. Multiple surgical and radiation modifications are available nowadays, allowing urologists to offer various treatments for better functional lower urinary tract outcomes. Diagnosing and understanding the type and severity of voiding dysfunction plays a key role in tailoring an appropriate treatment plan. The objective to better functional results relies on maintaining adequate bladder compliance and capacity while permitting volitional emptying, ideally through voiding. Management should routinely start with conservative measures, including pelvic floor muscle training with or without a combination of oral medication for urgency incontinence and clean intermittent catheterization for the management of urinary retention. Concomitant or isolated urinary incontinence can be further managed through multiple established surgical approaches. We attempted to address various treatment available for known lower urinary tract symptoms that might have been caused secondary to non-urological pelvic surgery or radiation. We discuss different diagnostic and treatment modalities individualized for patients with various entities, to help achieve optimal urinary function and improve quality of life.

Voiding Dysfunction After Non-urologic Pelvic Surgery

PURPOSE OF REVIEW

Urinary dysfunction is a common entity in patients undergoing radical pelvic surgery for non-urologic malignancies. These dysfunctions may manifest as lower urinary tract symptoms (LUTS) or signs such as urinary retention or leakage. Review of current literature is performed to describe the differing urinary dysfunctions that manifest after colorectal resection, hysterectomy, and sacrectomy.

RECENT FINDINGS

Conventional radical surgery for pelvic malignancies often will result in debilitating functional problems. As advances in surgical techniques and management options become more available, patients can have better functional outcomes, specifically in the lower urinary tract. Nerve-sparing techniques as well as vascular preservation are becoming more important to preserve function as patient survival is improving. Additionally, newer methods are being explored, such as nerve stimulation for those who are unable to empty adequately. This article also addresses different management options for specific voiding dysfunction that may result from pelvic surgery. Preventative strategies such as nerve preservation during surgery are an important concept to prevent urinary dysfunction. The goal to good functional outcomes includes maintaining reservoir compliance and capacity as well as allowing proper outlet for voiding. We discuss different modalities to help achieve a functional lower urinary tract for patients with lower urinary tract dysfunction after pelvic surgery.

How to deal with rectal lesions more than 15 cm from the anal verge through transanal endoscopic microsurgery

BACKGROUND

The aim of this study is to assess postoperative morbidity and mortality in tumors with a proximal margin 15 cm or more from the anal verge operated with transanal endoscopic microsurgery (TEM).

METHODS

This observational study of consecutive rectal tumor patients undergoing TEM was carried out from July 2004 to June 2017. We compared the results of rectal tumors at distances of ≥15 cm (group A) and <15 cm (group B) from the anal verge.

RESULTS

During the study period 667 patients were included: 118 in group A and 549 in group B. In the comparative analysis there were no significant differences in morbidity (p = 0.23), mortality (p = 0.32) or free margin involvement (p = 0.545). Differences were observed in terms of lesion size (p < 0.001), surgical time (p < 0.001) and peritoneal cavity perforation, which were all increased in group A.

CONCLUSION

TEM for lesions in the rectosigmoid junction is feasible and is not associated with higher morbidity or mortality.

Is There Any Reason to Still Consider Lateral Lymph Node Dissection in Rectal Cancer? Rationale and Technique

Nodal dissemination in locally advanced rectal cancer occurs mainly in two directions: upward and lateral. Lateral node involvement has been demonstrated; however, lateral lymph node dissection (LLND) is not routinely performed in Western countries and the focus is more on neoadjuvant treatment regimens. The main reasons for this are the high morbidity associated with the operation and the uncertain oncological benefit. There is, however, recent evidence that in selected cases, neoadjuvant treatment combined with total mesorectal excision only might not be sufficient. In this article, the historical developments in the East and the West, the current evidence regarding lateral nodal disease, and the surgical steps in the LLND are discussed.

Sexual dysfunction following rectal cancer surgery

INTRODUCTION

Sexual and urological problems after surgery for rectal cancer are common, multifactorial, inadequately discussed, and untreated. The urogenital function is dependent on dual autonomic sympathetic and parasympathetic innervation, and four key danger zones exist that are at risk for nerve damage during colorectal surgery: one of these sites is in the abdomen and three are in the pelvis. The aim of this study is to systematically review the epidemiology of sexual dysfunction following rectal cancer surgery, to describe the anatomical basis of autonomic nerve-preserving techniques, and to explore the scientific evidence available to support the laparoscopic or robotic approach over open surgery.

METHODS

According to the PRISMA guidelines, a comprehensive literature search of studies evaluating sexual function in patients undergoing rectal surgery for cancer was performed in Medline, Scopus, Web of Science, Embase, and Cochrane Central Register of controlled trials.

RESULTS

An increasing number of studies assessing the incidence and prevalence of sexual dysfunction following multimodality treatment for rectal cancer has been published over the last 30 years. Significant heterogeneity in the prevalence of sexual dysfunction is reported in the literature, with rates between 5 and 90%.

CONCLUSIONS

There is no evidence to date in favor of any surgical approach (open vs laparoscopic vs robotic). Standardized diagnostic tools should be routinely used to prospectively assess sexual function in patients undergoing rectal surgery.

Pelvic autonomic nerve preservation in radical rectal cancer surgery: changes in the past 3 decades

The advent of total mesorectal excision (TME) together with minimally invasive techniques such as laparoscopic colorectal surgery and robotic surgery has improved surgical results. However, the incidence of bladder and sexual dysfunction remains high. This may be particularly distressing for the patient and troublesome to manage for the surgeon when it does occur. The increased use of neoadjuvant and adjuvant radiotherapy is also associated with poorer functional outcomes. In this review, we evaluate current understanding of the anatomy of pelvic nerves which are divided into the areas of the inferior mesenteric artery pedicle, the lateral pelvic wall and dissection around the urogenital organs. Surgical techniques in these areas are discussed. We also discuss the results in functional outcomes of the various techniques including open, laparoscopic and robotic over the last 30 years.

Genitourinary Considerations in Reoperative and Complex Colorectal Surgery

Genitourinary structures are at risk of injury during colorectal surgery. The incidence of injury is low; however, the risk is higher in cases involving severe inflammatory or infectious processes, locally advanced or recurrent cancer, previous radiation, and reoperation. Consideration of the anatomical relationship between the genitourinary system, and the colon and rectum is crucial to avoid injuries. Intraoperative diagnostic techniques such as intravenous pyelogram (IVP), fluoroscopic cystogram, or retrograde urethrogram can aid in identifying suspected injuries. Early recognition and repair of injuries decrease the morbidity of an injury. Repair of injuries depends on the location and extent of the injury. Simple injuries may be repaired primarily, while complex injuries may require more advanced repairs such as a flap reconstruction.

Male urinary and sexual function after robotic pelvic autonomic nerve-preserving surgery for rectal cancer

BACKGROUND

Urinary and sexual dysfunction is the potential complication of rectal cancer surgery. The aim of this study was to evaluate the urinary and sexual function in male patients with robotic surgery for rectal cancer.

METHODS

This prospective study included 137 of the 336 male patients who underwent surgery for rectal cancer. Urinary and male sexual function was studied by means of a questionnaire based on the International Prostatic Symptom Score and International Index of Erectile Function. All data were collected before surgery and 12 months after surgery.

RESULTS

Patients who underwent robotic surgery had significantly decreased incidence of partial or complete erectile dysfunction and sexual dysfunction than patients with laparoscopic surgery. The pre- and post-operative total IPSS scores in patients with robotic surgery were significantly less than that with laparoscopic surgeries.

CONCLUSIONS

Robotic surgery shows distinct advantages in protecting the pelvic autonomic nerves and relieving post-operative sexual dysfunction.

Sphincter lesions observed on ultrasound after transanal endoscopic surgery

AIM: To assess the morphological impact of transanal endoscopic surgery on the sphincter apparatus using the modified Starck classification.

METHODS: A prospective, observational study of 118 consecutive patients undergoing Transanal Endoscopic Operation/Transanal Endoscopic Microsurgery (TEO/TEM) from March 2013 to May 2014 was performed. All the patients underwent an endoanal ultrasound prior to surgery and one and four months postoperatively in order to measure sphincter width, identify sphincter defects and to quantify them in terms of the level, depth and size of the affected anal canal. To assess the lesions, we used the “modified” Starck classification, which incorporates the variable “sphincter fragmentation”. The results were correlated with the Wexner incontinence questionnaire.

RESULTS: Of the 118 patients, twelve (sphincter lesions) were excluded. The results of the 106 patients were as follows after one month: 31 (29.2%) lesions found on ultrasound after one month, median overall Starck score of 4 (range 3-6); 10 (9.4%) defects in the internal anal sphincter (IAS) and 3 (2.8%) in the external anal sphincter (EAS); 17 patients (16%) had fragmentation of the sphincter apparatus with both sphincters affected in one case. At four months: 7 (6.6%) defects, all in the IAS, overall median Starck score of 4 (range 3-6). Mean IAS widths were 3.5 mm (SD 1.14) preoperatively, 4.38 mm (SD 2.1) one month postoperatively and 4.03 mm (SD 1.46) four months postoperatively. The only statistically significant difference in sphincter width in the IAS measurements was between preoperatively and one month postoperatively. No incontinence was reported, even in cases of ultrasound abnormalities.

CONCLUSION: TEO/TEM may produce ultrasound abnormalities but this is not accompanied by clinical changes in continence. The modified Starck classification is useful for describing and managing these disorders.

Study of anorectal function after transanal endoscopic surgery

AIM

To evaluate the impact of Transanal Endoscopic Microsurgery (TEM) on anorectal function, using clinical and manometric assessments. To identify subgroups likely to develop incontinence after TEM, by stratifying the sample.

METHOD

Descriptive, prospective study. Between December 2004 and May 2011, 222 patients were operated on at our hospital, of whom 21 were excluded from the study. Patients underwent anal manometry and answered a clinical incontinence questionnaire (the Wexner scale) prior to surgery, one month post-surgery, and then at four months post-surgery.

RESULTS

There were no statistically significant differences between preoperative Wexner questionnaire scores and values at one month and four months post-surgery. Preoperative baseline pressure (BP) values were 64 mmHg±26.18, falling to 44.26 mmHg±20.11 at one month and to 48.86 mmHg±21.14 at four months. Voluntary Contraction Pressure (VCP) reached preoperative values of 200.49 mmHg±88.85, falling to 169.5 mmHg±84.95 and to 173.6±79 at four months. The differences in BP and VCP were statistically significant. The sample was stratified in order to identify subsets susceptible to incontinence after surgery, but no at-risk subgroups were found. Multivariate analysis did not detect any predictors of incontinence.

CONCLUSION

The sustained, controlled anal dilatation produced with TEM caused statistically significant decreases in VCP and BP one month and four months after surgery. However, the Wexner questionnaire scores did not show any association with clinical incontinence. No predictors of postoperative incontinence were observed. We conclude that TEM is a safe technique and does not affect continence.

Mortality after common rectal surgery in Japan: a study on low anterior resection from a newly established nationwide large-scale clinical database

BACKGROUND

The health-care system, homogenous ethnicity, and operative strategy for lower rectal cancer surgery in Japan are to some extent unique compared to those in Western countries. The National Clinical Database is a newly established nationwide, large-scale surgical database in Japan.

OBJECTIVE

To illuminate Japanese national standards of clinical care and provide a basis for efforts to optimize patient care, we used this database to construct a risk model for a common procedure in colorectal surgery-low anterior resection for lower rectal cancer.

DESIGN

Data from the National Clinical Database on patients who underwent low anterior resection during 2011 were analyzed. Multiple logistic regression analyses were performed to generate predictive models of 30-day mortality and operative mortality. Receiver-operator characteristic curves were generated, and the concordance index was used to assess the model's discriminatory ability.

RESULTS

During the study period, data from 16,695 patients who had undergone low anterior resection were collected. The mean age was 66.2 years and 64.5% were male; 1.1% required an emergency procedure. Raw 30-day mortality was 0.4% and operative mortality was 0.9%. The postoperative incidence of anastomotic leakage was 10.2%. The risk model showed the following variables to be independent risk factors for both 30-day and operative mortality: BMI greater than 30 kg/m, previous peripheral vascular disease, preoperative transfusions, and disseminated cancer. The concordance indices were 0.77 for operative mortality and 0.75 for 30-day mortality.

LIMITATIONS

The National Clinical Database is newly established and data entry depends on each hospital.

CONCLUSIONS

This is the first report of risk stratification on low anterior resection, as representative of rectal surgery, with the use of the large-scale national surgical database that we have recently established in Japan. The resulting risk models for 30-day and operative mortality from rectal surgery may provide important insights into the delivery of health care for patients undergoing GI surgery worldwide.

Colorectal surgery and its impact on male sexual function

The quality of functional outcome has become increasingly important in view of improvement in prognosis with colorectal cancer patients. Sexual dysfunction remains a common problem after colorectal cancer treatment, despite the good oncologic outcomes achieved by expert surgeons. Although radiotherapy and chemotherapy contribute, surgical nerve damage is the main cause of sexual dysfunction. The autonomic nerves are in close contact with the visceral pelvic fascia that surrounds the mesorectum. The concept of total mesorectal excision (TME) in rectal cancer treatment has led to a substantial improvement of autonomic nerve preservation. In addition, use of laparoscopy has allowed favorable results with regards to sexual function. The present paper describes the anatomy and pathophysiology of autonomic pelvic nerves, prevalence of sexual dysfunction, and the surgical technique of nerve preservation in order to maintain sexual function.

A systematic review of the correlates and management of nonpremature ejaculatory dysfunction in heterosexual men

INTRODUCTION

A better understanding of ejaculatory disorders has led to an increasing interest in nonpremature ejaculatory dysfunction (non-PE EjD). Current reviews on the subject use a symptom-based classification to describe ejaculatory dysfunction even when it is a single case report. While these reviews provide important information on the disorder, a clearer picture of the prevalence of non-PE EjD in relation to the community and various pathophysiologic states is needed.

OBJECTIVES

The objective of this study was to provide a systematic review of studies of non-PE EjD excluding single case reports.

METHODS

A systematic review of Medline for terms including ejaculation, orgasm or hematospermia. Association with terms delay, pain or headache was made. The search was restricted to male gender and articles written in English. Abstracts were reviewed and those mainly concerned with premature ejaculation were excluded.

RESULTS

A total of 333 articles on non-PE EjD were identified. The condition was reported in community-based studies. In certain patient populations, non-PE EjD was commonly reported in association with antidepressant and antipsychotic treatments, in patients with chronic prostatitis/chronic pelvic pain syndrome, patients with lower urinary tract symptoms particularly in association with medical or surgical treatment, patients with retroperitoneal surgery and in patients with neurological diseases. Few articles were concerned with treatment options.

CONCLUSION

There is a significant prevalence of non-PE EjD in the community and in association with particular disease states or as a side effect of medical or surgical interventions. There is a need to direct efforts to prevent and treat these conditions.

Male sexual dysfunction after rectal cancer surgery

PURPOSE

The aims of the study were to determine the extent of male sexual dysfunction after surgical treatment of rectal cancer and to examine the outcome of postoperative treatment with sildenafil.

METHODS

A prospective study was performed in patients who underwent attempted curative total mesorectal excision (TME) for low rectal cancers. Sexual function scores were determined by questionnaire preoperatively and at 3 and 12 months postoperatively. Outcomes were examined in patients who were sexually active preoperatively.

RESULTS

From 2000 to 2007, 207 patients underwent TME at our institution, of whom 49 (24%) were sexually active preoperatively. Erectile dysfunction and ejaculatory problems were present in 80% and 82%, respectively of the 49 patients at 3 months postoperatively, and in 76% and 67%, respectively at 12 months. Lateral lymph node dissection was a strong risk factor for postoperative sexual dysfunction. The impotency rate was 37% and 47% of patients were unable to ejaculate. Sildenafil was administered to 16 patients who requested the drug during follow-up, and sexual dysfunction was improved in 11 of these patients (69%).

CONCLUSION

Sexual dysfunction occurs frequently after rectal cancer treatment and is mainly caused by surgical damage in lateral lymph node dissection. Sildenafil may be effective for the treatment of sexual dysfunction.

Quality of life after surgery for rectal cancer with special reference to pelvic floor dysfunction

AIM

Conventional outcomes such as survival, tumour recurrence and complication rates after surgery for rectal cancer have been rigorously assessed, but the importance of maintaining quality of life (QOL) after surgery for rectal cancer has received less attention. The aim of the current study was to analyse QOL and the occurrence of pelvic dysfunction after the surgical treatment of rectal cancer.

METHOD

Between May 2005 and May 2008, 150 patients with rectal cancer underwent abdominoperineal resection (APR) or anterior resection (AR). Seventy-four answered two preoperative questionnaires. At a follow up of 1 year, 65 were alive without sign of recurrence and answered the same questionnaires: (a) validated RAND 36-item health survey QOL questionnaire; and (b) self-administered disease-related questionnaire with special reference to anorectal and urogenital function.

RESULTS

The postoperative general QOL was similar after surgery, and mental functioning was better (P < 0.001). Problems with physical functions were associated with anal dysfunction after AR (P < 0.001) and problems with social functioning were associated with urinary dysfunction (P = 0.038). At 1 year after surgery, urinary incontinence was worse (P = 0.026) after all operations, and the incidence of dysuria was higher after APR than AR (P = 0.001). Male sexual function also worsened (P = 0.060). Anorectal dysfunction caused more inconvenience among patients who underwent AR (P = 0.028). Preoperative radiation was associated with postoperative ejaculation problems (P = 0.028) and anal incontinence (P = 0.012).

CONCLUSION

Factors affecting QOL and pelvic floor function should be taken into account when making treatment decisions in rectal cancer.

Selective pelvic autonomic nerve stimulation with simultaneous intraoperative monitoring of internal anal sphincter and bladder innervation

BACKGROUND

Pelvic autonomic nerve preservation avoids postoperative functional disturbances. The aim of this feasibility study was to develop a neuromonitoring system with simultaneous intraoperative verification of internal anal sphincter (IAS) activity and intravesical pressure.

METHODS

14 pigs underwent low anterior rectal resection. During intermittent bipolar electric stimulation of the inferior hypogastric plexus (IHP) and the pelvic splanchnic nerves (PSN), electromyographic signals of the IAS and manometry of the urinary bladder were observed simultaneously.

RESULTS

Stimulation of IHP and PSN as well as simultaneous intraoperative monitoring could be realized with an adapted neuromonitoring device. Neurostimulation resulted in either bladder or IAS activation or concerted activation of both. Intravesical pressure increase as well as amplitude increase of the IAS neuromonitoring signal did not differ significantly between stimulation of IHP and PSN [6.0 cm H(2)O (interquartile range [IQR] 3.5-9.0) vs. 6.0 cm H(2)O (IQR 3.0-10.0) and 12.1 μV (IQR 3.0-36.7) vs. 40.1 μV (IQR 9.0-64.3)] (p > 0.05).

CONCLUSIONS

Pelvic autonomic nerve stimulation with simultaneous intraoperative monitoring of IAS and bladder innervation is feasible. The method may enable neuromonitoring with increasing selectivity for pelvic autonomic nerve preservation.

Sexual and urinary functioning after rectal surgery: a prospective comparative study with a median follow-up of 8.5 years

PURPOSE

The purpose of this study was to prospectively compare rectal resection (RR) with colonic resection on sexual, urinary and bowel function and quality of life in both short-term and long-term.

METHODS

Eighty-three patients who underwent RR were compared to 53 patients who underwent a colonic resection leaving the rectum in situ (RIS). A questionnaire assessing sexual, urinary and bowel functioning with a quality of life questionnaire (SF-36) was sent to all participants preoperatively, 3 and 12 months postoperatively and approximately 8 years after the onset of the study.

RESULTS

Short-term dysfunction included diminished sexual activity in female RR patients at 3 months and significantly more erectile dysfunction in RR patients 1 year postoperatively. Long-term dysfunction included more frequent and more severe erectile dysfunction in RR patients compared to RIS patients. These short-term and long-term outcomes did not influence overall quality of life. The incidence of urinary dysfunction was comparable between both groups. Bowel functioning was significantly better in the RIS group compared to the RR group 3 months and 1 year postoperatively.

CONCLUSIONS

Patients who underwent RR experienced up to 1 year postoperatively more sexual and bowel function problems than RIS patients. However, short-term and long-term dysfunction did not influence overall quality of life. Erectile dysfunction in male RR patients persisted in time, whereas other aspects of sexual, urinary and bowel function after RR and colonic resection are similar after a median follow-up of 8.5 years.

Sexual function after treatment for rectal cancer: a review

Sexual function is one element of QOL that may be significantly altered following treatment for rectal cancer, but the incidence and contributing risk factors are generally poorly understood. Nevertheless, the impact of rectal cancer therapy on sexual function should be conveyed to patients preoperatively. In addition to helping patients evolve realistic expectations, it will help clinicians identify those for whom interventions may be appropriate. In the past 10 years, there has been an increase in the number of studies reporting sexual dysfunction following rectal cancer treatment. However, these studies are difficult to interpret collectively for a variety of reasons. Most importantly, sexual dysfunction lacks a standardized definition, which leads to poor comparability between studies. The best inclusive definitions describe sexual dysfunction as a collection of distinct symptoms, which differ for men and women. The absence of sexual activity is sometimes used as a surrogate for sexual dysfunction, but this is confounded by an individual's desire and opportunity for sexual activity, and may not be an accurate reflection of physiologic functionality. Additional factors complicating assimilation of studies include the absence of baseline data, missing data, small sample sizes, and heterogeneity in use of validated and nonvalidated instruments. The purpose of this article is to systematically review the contemporary literature reporting sexual function after rectal surgery to determine the overall risk of sexual dysfunction, evaluate possible contributing factors, and identify questions that should be addressed in future studies.

Voiding and sexual function after autonomic-nerve-preserving surgery for rectal cancer in disease-free male patients

Purpose

We evaluated the effects of surgery for rectal cancer on postoperative voiding and sexual function over the course of time.

Materials and Methods

Data from 28 patients who underwent autonomic nerve preserving rectal cancer surgery were retrospectively analyzed. Operations were performed between October 2005 and July 2007 and all patients were followed-up for more than 3 years. Preoperatively, all patients underwent urodynamic studies including uroflowmetry, and filled out the International Prostate Symptom Score (IPSS). The evaluation of sexual function consisted of Erectile Function domain score in International Index of Erectile Function (IIEF-EFD) and Ejaculation domain score in Male Sexual Health Questionnaire (MSHQ-EjD). Data from uroflowmetry and questionnaires were examined.

Results

At 3 years postoperatively the prostate volume was similar to the preoperative value (p=0.727). There were no statistically significant postoperative changes in the average maximum flow rate (15.9 ml/s vs. 16.2 ml/s, p=0.637) and post-void residual urine volume (34.7 ml vs. 36.8 ml, p=0.809). No statistically significant differences were observed in the IPSS (13.2 vs. 12.2, p=0.374). However, although pelvic autonomic nerve preservation have been performed, a significant proportion of rectal cancer patients suffer from sexual dysfunction and the average of IIEF-EFD and MSHQ-EjD scores was decreased postoperatively until 3 years (25.1 vs. 16.1 and 28.3 vs. 14.2 respectively, p<0.001).

Conclusions

Voiding function was not affected after autonomic nerve-preserving rectal cancer surgery, however sexual function was significantly aggravated. We recommend that the baseline genitourinary function should be evaluated before the treatment for male rectal cancer patients, and penile rehabilitation is necessary for their quality of life after treatment.

Urinary and sexual dysfunction after rectal cancer treatment

In light of the improving prognosis for patients with rectal cancer, the quality of functional outcome has become increasingly important. Despite the good functional results achieved by expert surgeons, large multicenter studies show that urogenital dysfunction remains a common problem after rectal cancer treatment. More than half of patients experience a deterioration in sexual function, consisting of ejaculatory problems and impotence in men and vaginal dryness and dyspareunia in women. Urinary dysfunction occurs in one-third of patients treated for rectal cancer. Surgical nerve damage is the main cause of urinary dysfunction. Radiotherapy seems to have a role in the development of sexual dysfunction, without affecting urinary function. Pelvic autonomic nerves are especially at risk in cases of low rectal cancer and during abdominoperineal resection. Data concerning nerve damage during laparoscopic surgery for resection of rectal cancer are awaited. Structured education of surgeons with regard to pelvic neuroanatomy, and systematic registration of identified nerves, could well be the key to improving functional outcome for these patients. Meanwhile, patients should be informed of all associated risks before their operation, and their functional status should be evaluated before and after surgery.

[Analysis of the quality of surgical treatment of colorectal cancer, in 2008. A national study]

OBJECTIVE

A national study conducted for the Spanish Association of Surgeons with the aim of analysing the surgical treatment of colorectal cancer (CRC) in Spain and to compare it with scientific literature.

MATERIAL AND METHODS

A multicentre, descriptive, prospective and longitudinal study of patients with CRC who were treated by elective surgery. A total of 50 hospitals in 15 Autonomous Regions took part, with 496 treated cases in 2008. A total of 88 variables were collected.

RESULTS

The median age was 72 years, increase in ASA III patients; correct preoperative studies, 4% with no staging in the rectum. There was a tendency not to use the colon cleansing or to do it only one day. The percentage of complications is within the ranges in the literature, with the exception of surgical wound infections (19%). Mean of resected lymph nodes: 13.2; 4.3% no mesorectal resection. Mechanical anastomosis: 80.8%, 65.9% of the operations performed by a colorectal surgeon. Preoperative radiotherapy in 43.5% of rectal cancers. Chemotherapy: 32.9%. Laparoscopy: 35.1% of cases, conversion rate 13.8%. Use of antibiotics: 37.1%, blood transfusion: 20.6% and parenteral nutrition: 26.5%.

CONCLUSIONS

Surgical treatment of CRC in Spain has a level of quality and peri-operative results similar to the rest of Europe. Compared to previous studies, it was observed that there were advances in preparation of the patient, preoperative studies, imaging techniques, and improvements in surgical techniques with adoption of mesorectal excision, appropriate lymphadenectomies and preservation of sphincters. There are areas for improvement, such as a reduction in surgical wound infections, increase use of protective stoma, appropriate use of antibiotics, parenteral nutrition or neoadjuvants and complete colonoscopies.

Urinary bladder catheter drainage following pelvic surgery--is it necessary for that long?

PURPOSE

Urinary bladder drainage for several days after pelvic surgery is a common surgical practice, despite insufficient evidence supporting its routine use. The aim of this study was to prospectively evaluate the utility of urinary bladder drainage after pelvic colorectal surgery.

METHODS

Patients undergoing pelvic surgery were prospectively randomly assigned to 3 groups. In group A, the Foley catheter was removed on postoperative day 1, and in groups B and C it was removed on postoperative days 3 and 5, respectively. Male patients with severe prostatic symptoms were excluded from the study. The main outcome criterion was acute urinary retention requiring reinsertion of the Foley catheter.

RESULTS

A total of 118 patients (68 males) at a mean age of 55 years were included in this study (group A, 41 patients; group B, 38; and group C, 39). Overall, urinary retention after removal of the Foley catheter occurred in 12 (10%) of the patients: 6 (14.6%) in group A, 2 (5.3%) in group B, and 4 (10.5%) in group C (P = .39). Symptomatic urinary tract infection was diagnosed in 5 patients in group A, 3 in group B, and 9 in group C, but this difference did not reach statistical significance. Likewise, there were no significant differences in anastomotic leak and intra-abdominal abscess rates among the 3 groups.

CONCLUSIONS

Routine prolonged urinary bladder catheterization after pelvic surgery may not be required, and the Foley catheter may be safely removed on postoperative day 1. Larger studies are needed to confirm the findings of this study.

How to optimize autonomic nerve preservation in total mesorectal excision: clinical topography and morphology of pelvic nerves and fasciae

BACKGROUND

Urogenital dysfunction after rectal and pelvic surgery was significantly decreased with the introduction of nerve-preserving dissection and total mesorectal excision (TME). Profound topographic knowledge of the pelvic connective tissue spaces is indispensable for identification and preservation of autonomic pelvic nerves. The purpose of this cadaver study was to highlight the course of important autonomous nerve structures and to identify potential injury sites.

METHODS

Eleven cadavers were dissected according to TME with subsequent preparation of the pelvic nerves. The pelves of further three cadavers were sliced horizontally and cubed. Specimens were harvested and processed for light microscopy and immunohistochemistry to analyze both fascia and the types of nerves and their localization.

RESULTS

The neurovascular bundle, arising from the inferior pelvic plexus, shows the highest nerve density. At the lateral edge of Denonvilliers' fascia, it pierces the parietal pelvic fascia. Several fine nerve branches spread into the loose periprostatic tissue up to the prostate or pass the prostate toward the urinary bladder. En route, we consistently find perikarya of autonomic nerves. Within the mesorectum, nerve fibers are distributed heterogeneously with laterally high densities, ventrally and dorsally low densities.

CONCLUSION

The highest risk for pelvic nerve damage-apart from lesions of the superior hypogastric plexus itself-is anterolaterally of the rectum where the neurovascular bundle releases from the pelvic sidewall. Careful dissection helps to identify and protect these nerve structures. The retroprostatic Denonvilliers' fascia contains no important nerve structures.

One hundred years of curative surgery for rectal cancer: 1908-2008

In 1908, William Ernest Miles published his article in the Lancet, introducing the basis of modern rectal cancer surgery. He established the basis for curative cancer treatment by combining the knowledge of anatomy and biological behaviour with improved surgical options as a result of better anaesthesiological techniques. Miles' contribution comprised the introduction of the concept of lymphatic spread of cancer cells and his consequent radical surgical resection, removing all primary lymph nodes en bloc. Miles' concept has dominated the minds of surgeons throughout the 20th century and his abdominoperineal resection has been the golden standard for several decades. However, his concept of downward spread of rectal cancer was proven wrong, which initiated the historical shift from radical abdominoperineal resection to the use of sphincter-saving surgery. Since the introduction of total mesorectal excision, abdominoperineal excision has been performed in only a minority of patients. Further improvement in surgical technique consisted of autonomic nerve preservation, improving functional outcome. From a historical overview, it can be concluded that the management of rectal cancer has been progressed tremendously over the past 100 years, mainly because of an increased understanding of the pathology and natural history of the disease, which has been initiated by Miles.

Causes of Fecal and Urinary Incontinence After Total Mesorectal Excision for Rectal Cancer Based on Cadaveric Surgery: A Study From the Cooperative Clinical Investigators of the Dutch Total Mesorectal Excision Trial

Purpose

Total mesorectal excision (TME) for rectal cancer may result in anorectal and urogenital dysfunction. We aimed to study possible nerve disruption during TME and its consequences for functional outcome. Because the levator ani muscle plays an important role in both urinary and fecal continence, an explanation could be peroperative damage of the nerve supply to the levator ani muscle.

Methods

TME was performed on cadaver pelves. Subsequently, the anatomy of the pelvic floor innervation and its relation to the pelvic autonomic innervation and the mesorectum were studied. Additionally, data from the Dutch TME trial were analyzed to relate anorectal and urinary dysfunction to possible nerve damage during TME procedure.

Results

Cadaver TME surgery demonstrated that, especially in low tumors, the pelvic floor innervation can be damaged. Furthermore, the origin of the levator ani nerve was located in close proximity of the origin of the pelvic splanchnic nerves. Analysis of the TME trial data showed that newly developed urinary and fecal incontinence was present in 33.7% and 38.8% of patients, respectively. Both types of incontinence were significantly associated with each other (P = .027). Low anastomosis was significantly associated with urinary incontinence (P = .049). One third of the patients with newly developed urinary and fecal incontinence also reported difficulty in bladder emptying, for which excessive perioperative blood loss was a significant risk factor.

Conclusion

Perioperative damage to the pelvic floor innervation could contribute to fecal and urinary incontinence after TME, especially in case of a low anastomosis or damage to the pelvic splanchnic nerves.

Anorectal, bladder, and sexual function in females following colorectal surgery for carcinoma

BACKGROUND

The aim of this study was to establish the incidence of potential postoperative anorectal, bladder, and sexual dysfunction in women following excision of rectal cancer with total mesorectal excision (TME).

MATERIALS AND METHODS

All women who underwent a transabdominal rectal resection with TME for cancer between 2000 and 2003 were included. Women with a colonic resection for cancer during the same time period served as the control group. Exclusion criteria were strict. Standardized questionnaires were sent to all patients.

RESULTS

Twenty-six patients fulfilled the inclusion criteria and were evaluated. Fifteen patients had TME and 11 patients had colonic resection. The median Wexner score showed a higher rate of anal incontinence in the rectal group. The difference was due to a higher rate of severe incontinence in the rectal group. The King's Health Questionnaire showed normal urinary function in both groups. The Female Sexual Function Index showed worse sexual function in the rectal group, reaching statistical significance in the categories 'arousal' and 'lubrication'.

CONCLUSION

After rectal excision, the women showed impairment of their anorectal and sexual function. Urinary function was normal. This is in contrast to the incidence of urinary dysfunction in men observed by others. Our study indicates that women seem to have less functional problems when compared to literature data on dysfunction in male following rectal surgery for cancer.

Urinary dysfunction after rectal cancer treatment is mainly caused by surgery

BACKGROUND

Urinary dysfunction (UD) is common after rectal cancer treatment, but the contribution of each treatment component (surgery and radiotherapy) to its development remains unclear. This study aimed to evaluate UD during 5 years after total mesorectal excision (TME) and to investigate the influence of preoperative radiotherapy (PRT) and surgical factors.

METHODS

Patients with operable rectal cancer were randomized to TME with or without PRT. Questionnaires concerning UD were completed by 785 patients before and at several time points after surgery. Possible risk factors, including PRT, demographics, tumour location, and type and extent of resection, were investigated by multivariable regression analysis.

RESULTS

Long-term incontinence was reported by 38.1 per cent of patients, of whom 72.0 per cent had normal preoperative function. Preoperative incontinence (relative risk (RR) 2.75, P = 0.001) and female sex (RR 2.77, P < 0.001) were independent risk factors. Long-term difficulty in bladder emptying was reported by 30.6 per cent of patients, of whom 65.0 per cent had normal preoperative function. Preoperative difficulty in bladder emptying (RR 2.94, P < 0.001), peroperative blood loss (RR 1.73, P = 0.028) and autonomic nerve damage (RR 2.82, P = 0.024) were independent risk factors. PRT was not associated with UD.

CONCLUSION

UD is a significant clinical problem after rectal cancer treatment and is not related to PRT, but rather to surgical nerve damage.

Effects of NGF, NT-3 and GDNF family members on neurite outgrowth and migration from pelvic ganglia from embryonic and newborn mice

Background

Pelvic ganglia are derived from the sacral neural crest and contain both sympathetic and parasympathetic neurons. Various members of the neurotrophin and GDNF families of neurotrophic factors have been shown to play important roles in the development of a variety of peripheral sympathetic and parasympathetic neurons; however, to date, the role of these factors in the development of pelvic ganglia has been limited to postnatal and older ages. We examined the effects of NGF, NT-3, GDNF, neurturin and artemin on cell migration and neurite outgrowth from explants of the pelvic ganglia from embryonic and newborn mice grown on collagen gels, and correlated the responses with the immunohistochemical localization of the relevant receptors in fixed tissue.

Results

Cell migration assays showed that GDNF strongly stimulated migration of tyrosine hydroxylase (TH) cells of pelvic ganglia from E11.5, E14.5 and P0 mice. Other factors also promoted TH cell migration, although to a lesser extent and only at discrete developmental stages. The cells and neurites of the pelvic ganglia were responsive to each of the GDNF family ligands – GDNF, neurturin and artemin – from E11.5 onwards. In contrast, NGF and NT-3 did not elicit a significant neurite outgrowth effect until E14.5 onwards. Artemin and NGF promoted significant outgrowth of sympathetic (TH+) neurites only, whereas neurturin affected primarily parasympathetic (TH-negative) neurite outgrowth, and GDNF and NT-3 enhanced both sympathetic and parasympathetic neurite outgrowth. In comparison, collagen gel assays using gut explants from E11.5 and E14.5 mice showed neurite outgrowth only in response to GDNF at E11.5 and to neurturin only in E14.5 mice.

Conclusion

Our data show that there are both age-dependent and neuron type-dependent differences in the responsiveness of embryonic and neo-natal pelvic ganglion neurons to growth factors.

Evidence and research in rectal cancer

The main evidences of epidemiology, diagnostic imaging, pathology, surgery, radiotherapy, chemotherapy and follow-up are reviewed to optimize the routine treatment of rectal cancer according to a multidisciplinary approach. This paper reports on the knowledge shared between different specialists involved in the design and management of the multidisciplinary ESTRO Teaching Course on Rectal Cancer. The scenario of ongoing research is also addressed. In this time of changing treatments, it clearly appears that a common standard for large heterogeneous patient groups have to be substituted by more individualised therapies based on clinical-pathological features and very soon on molecular and genetic markers. Only trained multidisciplinary teams can face this new challenge and tailor the treatments according to the best scientific evidence for each patient.

Postoperative urinary retention after primary colorectal cancer resection via laparotomy: a prospective study of 2,355 consecutive patients

PURPOSE

The risk factors for postoperative urinary retention after colorectal carcinoma surgery can be clearly defined. This study was designed to determine risk factors for postoperative urinary retention after colorectal cancer surgery.

METHODS

A total of 2,355 consecutive patients with colorectal cancer who underwent open resection for colorectal cancer during a four-year period were included. The association between dependent and independent variables (including 19 clinicopathologic and surgical factors) was analyzed by using the chi-squared test or Fisher's exact test, as appropriate. The significant variables in the univariate analyses were included in multivariate analysis.

RESULTS

The overall prevalence of postoperative urinary retention was 5.5 percent (colon cancer, 1.7 percent; rectal cancer, 9.1 percent, P < 0.0001). Multivariate analysis showed an independent association between postoperative urinary retention and age, lung disease, tumor location, operation duration, and additional pelvic procedure. Of the 121 patients with postoperative urinary retention, urine catheterization was required in 42 patients one month postoperatively. Discriminate analysis showed that gender, American Society of Anesthesiologists' score, tumor location, presence of drainage, and pelvic infection were best able to discriminate between prolonged (>1 month) and transient urinary dysfunction.

CONCLUSIONS

Older patients, lung disease, rectal cancer, longer operation duration, and additional pelvic procedure were at greater risk. There is a time-dependent change in postoperative urinary dysfunction. Male gender, American Society of Anesthesiologists' score of 2 or 3, rectal tumor, surgical drain, and pelvic infection can identify patients at risk for prolonged urinary dysfunction.