Validation of the Danish Colorectal Cancer Group (DCCG.dk) database - on behalf of the Danish Colorectal Cancer Group.

AIM: The aim of this study was to validate the clinical quality database of the Danish Colorectal Cancer Group. The validation is meant to focus on core data regarding staging of the disease, treatment provided, patient-related factors and key complications. METHOD: This was a database validation study assessing the completeness of the database and the accuracy of the data by re-entering core variables into an online module in a blinded fashion and comparing re-entered data with the original database data. A sample of 5% of patients from the years 2014-2017 was randomly selected. RESULTS: The sample of 936 patients was identified and data were re-entered. The completeness of the data retrieved was a median of 96%, 100% and 99% for preoperative, intra-operative and postoperative variables, respectively. The overall accuracy was a median of 95%. The least accurate variable was date of diagnosis (50% perfect agreement), with agreement rising to 96% when near matches defined as correct date ± 30 days were included. Intra-operative variables were of high quality, as were data on surgical complications including anastomotic leakage, where agreement was 97%. CONCLUSION: This was the first major validation of the Danish Colorectal Cancer Group's database. Overall, the completeness and quality of data were high, but the validation process also identified weaknesses, which can be crucial for future users to acknowledge and consider.

Impact of bowel and stoma dysfunction on female sexuality after treatment for rectal cancer.

AIM: The aim of this study was to measure the impact of bowel dysfunction and a poorly functioning stoma on the risk of sexual inactivity and sexual dysfunction in female patients. METHOD: In a population-based cross-sectional study, Danish rectal cancer patients diagnosed between 2001 and 2014 were invited to answer a comprehensive questionnaire regarding cancer- and treatment-related late side effects after rectal cancer treatment. Bowel function was assessed using the Low Anterior Resection score and stoma function using the Colostomy Impact score. Female sexuality was measured by sexual activity, overall sexual dysfunction (the Rectal Cancer Female Sexuality score) and by different domains of sexual dysfunction (Sexual Vaginal Changes questionnaire). RESULTS: Eight-hundred and thirteen female patients completed the questionnaire (response rate 49.2%). Major bowel dysfunction did not significantly increase the risk of sexual inactivity (OR 1.39, 95% CI 0.93-2.07) but clearly increased the risk of sexual dysfunction (OR 3.03, 95% CI 1.67-5.51). The most distinct problems were dyspareunia and inability to complete intercourse. On the contrary, poor stoma function increased the risk sexual inactivity (OR 2.26, 95% CI 1.16-4.40) but not the risk of sexual dysfunction (OR 0.74, 95% CI 0.27-1.99). The most distinct problem was dissatisfaction with own physical appearance. CONCLUSIONS: Both bowel dysfunction and stoma dysfunction negatively, but differently, affect sexuality. After restorative surgery, bowel dysfunction was primarily associated with sexual dysfunction while poor stoma function after abdominoperineal excision was associated with sexual inactivity.

Long-term impact of incisional hernia on quality of life after colonic cancer resection.

PURPOSE: The objective of the current study was to examine the long-term quality of life (QOL) after colonic cancer resection according to whether or not the patients developed incisional hernia. Furthermore, the impact of incisional hernia repair on QOL was examined in the patient group diagnosed with an incisional hernia. METHODS: This was a nationwide register-based study including patients undergoing colonic cancer resection identified in the Danish Colorectal Cancer Group database. Surviving patients were contacted and answered the EORTC QLQ-C30 questionnaire and grouped according to subsequent incisional hernia diagnosis, and in a subgroup analysis of patients with subsequent incisional hernia according to incisional hernia repair or not. RESULTS: A total of 2466 patients were included. The median time from colonic cancer resection to QOL assessment was 9.9 years, during which a total of 215 (8.7%) patients were diagnosed with incisional hernia, and 156 (72.6%) of these underwent incisional hernia repair. After adjustment for confounders, incisional hernia subsequent to colonic cancer resection was significantly associated with reduced QOL in the domains Global health, Physical functioning, Role functioning, Emotional functioning and Social functioning, as well as significantly associated with increased symptoms in the scales of pain, dyspnoea and insomnia. Of patients with incisional hernia, surgical repair was associated with increased QOL in the domains Physical functioning and Role functioning. CONCLUSIONS: Incisional hernia subsequent to colonic cancer resection was associated with reduced QOL several years after surgery and should be considered taken into account when evaluating the long-term outcome of colonic cancer resection.

Quality of life with or without sphincter preservation for rectal cancer.

AIM: The aim of this investigation was to examine quality of life after surgical treatment for low rectal cancer. METHOD: This was a population-based, cross-sectional study on quality of life in patients treated for rectal cancer from 2001 to 2007. The European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire (QLQ-C30) and a single question on the impact of bowel/stoma function on quality of life were sent to patients who had undergone abdominoperineal excision (APE) or low anterior resection (LAR) for rectal cancer with tumours below 10 cm from the anal verge. RESULTS: Informative answers were obtained from 898 patients (87%). EORTC QLQ-C30 outcomes were very similar for APE and LAR patients in univariate analysis. When adjusted for neoadjuvant radiotherapy and gender, multivariate analysis showed that LAR patients had lower global health status (OR 1.32, 95% CI 1.03; 1.68, P = 0.026) and higher occurrence of constipation (OR 0.47, 95% CI 0.32; 0.69, P < 0.001) and diarrhoea (OR 0.47, 95% CI 0.35; 0.64, P < 0.001). Analysis of the anchor question showed that LAR patients had significantly higher negative impact of bowel function on quality of life in both univariate (OR 3.38, 95% CI 2.62; 4.37, P < 0.001) and multivariate analysis (OR 3.71, 95% CI 2.86; 4.83, P < 0.001) compared with APE. CONCLUSION: For patients with low rectal cancer, we found LAR patients had worse global health status and problems with diarrhoea and constipation compared with APE patients.

Female sexual problems after treatment for colorectal cancer - a population-based study.

AIM: There has been limited focus on female sexuality after treatment for colorectal cancer. The aim of this study was to investigate long-term female sexual dysfunction in disease-free colorectal cancer survivors in the Danish population. METHOD: All female Danish patients treated for colorectal cancer between 2001 and 2014 were included if they reported to have been sexually active at the time of diagnosis. They were requested to answer the validated Sexual Vaginal Changes Questionnaire. RESULTS: A total of 2402 patients were included for analysis (43%). Overall, rectal cancer patients reported more sexual inactivity and problems compared to colon cancer patients, but there were no differences in any sexual function domains when excluding irradiated patients and patients with a permanent stoma. A permanent stoma was associated with sexual inactivity [OR 2.56 (95% CI 1.42-4.70)] and overall sexual dysfunction [OR 2.95 (95% CI 1.05-6.38)] in colon cancer patients, as well as inactivity [OR 1.43 (95% CI 1.01-2.04)] and overall dysfunction [OR 2.0 (95% CI 1.18-3.41)] in rectal cancer patients. Furthermore, a permanent stoma was associated with dyspareunia [OR 2.17 (95% CI 1.39-3.38)] and reduced vaginal dimension [OR 3.16 (95% CI 1.99-5.01)]. In rectal cancer patients, radiotherapy exposure increased the odds for overall sexual dysfunction [OR 1.80 (95% CI 1.02-3.16)] and was associated with dyspareunia [OR 1.72 (95% CI 0.95-3.12)]. CONCLUSION: Sexual problems after treatment of colorectal cancer are common. Major risk factors are a permanent stoma and radiotherapy. Relevant patients should be offered professional counselling and treatment.

Bowel dysfunction after sigmoid resection for cancer and its impact on quality of life.

BACKGROUND: Several studies have explored functional outcomes after rectal cancer surgery, but bowel dysfunction after sigmoid resection for cancer has hardly been considered. The aim of this study was to identify the prevalence and pattern of bowel dysfunction after resection for sigmoid cancer, and the impact of bowel function on quality of life (QoL) by comparison with patients who had polypectomy for cancer. METHODS: This was a national cross-sectional study. Data were collected from the Danish Colorectal Cancer Group database, and a questionnaire regarding bowel function and European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 QoL questionnaire was sent to all Danish colonic cancer survivors treated with sigmoid resection or polypectomy between 2001 and 2014. RESULTS: A total of 3295 patients (3061 sigmoid resection, 234 polypectomy) responded to the questionnaire (response rate 63·8 per cent). Twelve bowel symptoms were more prevalent after sigmoid resection, including: excessive straining, fragmentation, bloating, nocturnal defaecation, bowel false alarm, liquid stool incontinence, incomplete evacuation and sense of outlet obstruction. QoL impairment owing to bowel symptoms was reported in 16·6 per cent of patients in the resection group and 10·1 per cent after polypectomy (P = 0·008). Obstructed defaecation symptoms (ODS) were encountered significantly more often after sigmoid resection than following polypectomy (17·9 versus 7·3 per cent; P < 0·001). In the resection group, patients with ODS had substantial impairment on most aspects of QoL assessed by the EORTC QLQ-C30. CONCLUSION: Sigmoid resection for cancer is associated with an increased risk of long-term bowel dysfunction; obstructed defaecation is prevalent and associated with substantial impairment of QoL.

Chronic pain after rectal cancer surgery - development and validation of a scoring system.

AIM: The aim was to develop and validate a scoring system for the assessment of chronic pain on quality of life (QoL) following surgical treatment of rectal cancer (RC). METHOD: Patients diagnosed with RC between 2001 and 2014 in Denmark were evaluated for inclusion. Eligible patients were mailed questionnaires concerning pain and QoL. Questionnaire items were associated with QoL by odds ratio using regression analyses. The patients were randomized into a development group and a validation group. The most significant items were each assigned a score value based on multivariate-adjusted odds ratio. Validity was tested in the validation group using receiver operating characteristic curves and European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire - Core 30 (EORTC QLQ-30). RESULTS: A total of 1928 eligible patients completed the questionnaire; 1072 were randomized to the development group and 856 to the validation group. The calculated scores included the six most important questionnaire items giving a score range of 0-45 which identified three groups: no significant pain, minor pain syndrome and major pain syndrome. Our results suggest a significant correlation between QoL assessment and the presence of major pain. CONCLUSION: We have developed and validated a reliable, QoL-based scoring system for chronic post-surgical pain following RC.

The risk of long-term bowel dysfunction after resection for sigmoid adenocarcinoma: a cross-sectional survey comparing complete mesocolic excision with conventional surgery.

AIM: To investigate whether complete mesocolic excision (CME) might carry a higher risk of bowel dysfunction and subsequent reduction in quality of life compared with conventional resection. METHOD: A cross-sectional questionnaire study based on data from a national survey regarding long-term bowel function and a population-based cohort study comparing CME (study group) with conventional resection (control group). A total of 622 patients undergoing elective resection for Stage I-III sigmoid adenocarcinoma at four university colorectal centres between June 2008 and December 2014 were eligible to receive the questionnaire in mid-November 2015. Primary outcomes were four or more bowel movements daily, nocturnal bowel movements, unproductive call to stool, obstructive sensation and impact of bowel function on quality of life (QOL). RESULTS: One hundred and twenty-seven (69.0%) and 289 (66.0%) patients in the study and control groups, respectively, responded to the questionnaire after medians of 4.41 [interquartile range (IQR) 2.50, 5.83] and 4.57 (IQR 3.15, 5.82) years, respectively (P = 0.048). CME was not associated with: increased risk of four or more bowel movements daily [adjusted OR 1.14 (95% CI 0.59-2.14; P = 0.68)], nocturnal bowel movements [adjusted OR 1.31 (0.66-2.53; P = 0.43)], unproductive call to stool [adjusted OR 0.99 (0.54-1.77; P = 0.97)] or obstructive sensation [adjusted OR 1.01 (0.56-1.78; P = 0.96)]. While one in five patients in both groups had moderate to severe impact of bowel function on QOL, there was no association with CME. CONCLUSION: For patients with sigmoid cancer, CME is associated with neither higher risk of bowel dysfunction nor impaired QOL.

The colostomy impact score: development and validation of a patient reported outcome measure for rectal cancer patients with a permanent colostomy. A population-based study.

AIM: The aim was to develop and validate a simple scoring system evaluating the impact of colostomy dysfunction on quality of life (QOL) in patients with a permanent stoma after rectal cancer treatment. METHOD: In this population-based study, 610 patients with a permanent colostomy after previous rectal cancer treatment during the period 2001-2007 completed two questionnaires: (i) the basic stoma questionnaire consisting of 22 items about stoma function with one anchor question addressing the overall stoma impact on QOL and (ii) the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ) C30. Answers from half of the cohort were used to develop the score and subsequently validated on the remaining half. Logistic regression analyses identified and selected items for the score and multivariate analysis established the score value allocated to each item. RESULTS: The colostomy impact score includes seven items with a total range from 0 to 38 points. A score of ≥ 10 indicates major colostomy impact (Major CI). The score has a sensitivity of 85.7% for detecting patients with significant stoma impact on QOL. Using the EORTC QLQ scales, patients with Major CI experienced significant impairment in their QOL compared to the Minor CI group. CONCLUSION: This new scoring system appears valid for the assessment of the impact on QOL from having a permanent colostomy in a Danish rectal cancer population. It requires validation in non-Danish populations prior to its acceptance as a valuable patient-reported outcome measure for patients internationally.

Neoadjuvant therapy abolishes the functional benefits of a larger rectal remnant, as measured by magnetic resonance imaging after restorative rectal cancer surgery.

BACKGROUND: The combination of advances in surgical technique and neoadjuvant therapy for rectal cancer has resulted in more patients undergoing sphincter-preserving surgery. Unfortunately, numerous patients subsequently experience bowel dysfunction, and may suffer from lifelong severe disability with major impact on their quality of life. The aim of the present study was to investigate whether the risk of severe LARS in patients was associated with the length of remnant rectum. METHODS: A total of 125 patients who underwent sphincter-preserving surgery for rectal cancer were included. Postoperative bowel function was assessed using the low anterior resection syndrome (LARS) score a minimum of one year following surgery. The length of remnant rectum was measured on postoperative MRI of the pelvis and was correlated with the risk of having major LARS. RESULTS: Overall, major LARS was observed in 38 per cent of patients. In the patients who underwent surgery alone, major LARS was reported by 27 per cent, and a larger remnant rectum was associated with a better functional outcome. In contrast, 80 per cent of patients who underwent combined preoperative chemoradiotherapy and surgery reported having major LARS. No association between the length of remnant rectum and the risk of major LARS was observed in patients treated with combined neoadjuvant therapy and surgery. CONCLUSION: Both the length of remnant rectum and preoperative chemoradiotherapy had a major impact on the severity of bowel dysfunction after restorative rectal cancer surgery. No functional benefit from an irradiated rectal remnant was observed.

Life with a stoma after curative resection for rectal cancer: a population-based cross-sectional study.

AIM: The aim of the investigation was to examine life with a stoma after rectal cancer surgery. METHOD: This was a population-based, cross-sectional study of patients with a stoma treated for rectal cancer from 2001 to 2007. A questionnaire was mailed to patients who had undergone abdominoperineal excision, Hartmann's procedure and anterior resection with a permanent stoma. RESULTS: Informative answers were obtained from 644 (88%) of 732 patients. Most (91%) managed the stoma on their own. There was an impact of the stoma on the quality of life in 68% of patients but this was minor in 50%. Leakage of the appliance was reported in 59%, and 58% of patients were disturbed by the smell of faeces. A parastomal hernia was reported in 57% and pain at the stoma site in 30%. There was no association between the impact of the stoma on the quality of life and gender, type of surgery, use of radiochemotherapy or the interval from surgery. CONCLUSION: Most patients reported little or no impact on quality of life resulting from the stoma, but many patients were disturbed by the smell or leakage of faeces. The parastomal hernia rate was extremely high.

Validation of the English translation of the low anterior resection syndrome score.

AIM: Many patients having anterior resection for rectal cancer suffer from severe long-term bowel dysfunction, known as low anterior resection syndrome (LARS). The LARS score was developed in Denmark, and Swedish, Spanish and German versions have been validated. The aim of this study was to validate the English translation of the LARS score in British rectal cancer patients. METHOD: Rectal cancer patients who underwent an anterior resection in 12 UK centres received the LARS score questionnaire, the EORTC QLQ-C30 and a single ad hoc quality of life question. A subgroup of patients received the LARS score questionnaire twice. RESULTS: The response rate was 80% and 451 patients were included in the analyses. A strong association between LARS score and quality of life (convergent validity) was found (P < 0.01), discriminative validity was good (P < 0.02) and the test-retest reliability was high (intraclass correlation coefficient 0.83). CONCLUSION: The English translation of the LARS score has shown good psychometric properties comparable with recently published results from an international multicentre study. Thus, the English translation of the LARS score can be considered a valid and reliable tool for measuring LARS.

Urinary and sexual dysfunction in women after resection with and without preoperative radiotherapy for rectal cancer: a population-based cross-sectional study.

AIM: Knowledge of urinary and sexual dysfunction in women after rectal cancer treatment is limited. This study addresses this in relation to the use of preoperative radiotherapy, type of surgery and the presence of bowel dysfunction. METHOD: All living female patients who underwent abdominoperineal excision (APE) or low anterior resection (LAR) for rectal cancer in Denmark between 2001 and 2007 were identified. Validated questionnaires (the ICIQ-FLUTS and the SVQ) on urinary and sexual function were completed by 516 (75%) and 482 (72%) recurrence-free patients in 2009. RESULTS: Urgency and incontinence were reported by 77 and 63% of respondents, respectively. Vaginal dryness, dyspareunia and reduced vaginal dimensions occurred in 72, 53 and 29%, respectively, and 69% reported that they had little/no sexual desire. Preoperative radiotherapy was associated with voiding difficulties (OR = 1.63, 95% CI 1.09-2.44), reduced vaginal dimensions (OR = 4.77, 95% CI 1.97-11.55), dyspareunia (OR = 2.76, 95% CI 1.12-6.79), lack of desire (OR = 2.22, 95% CI 1.09-4.53) and reduced sexual activity (OR = 0.55, 95% CI 0.30-0.98). Patients undergoing APE had a higher risk of dyspareunia (OR = 2.61, 95% CI 1.00-6.85). Bowel dysfunction after LAR was associated with bladder storage difficulties (OR = 1.64, 95% CI 1.01-2.65), symptoms of incontinence (OR = 2.17, 95% CI 1.35-3.50), lack of sexual desire (OR = 2.69, 95% CI 1.21-5.98), sexual inactivity (OR = 0.48, 95% CI 0.24-0.96) and sexual dissatisfaction (OR = 0.40, 95% CI 0.20-0.82). CONCLUSION: Urinary and sexual problems are common in women after treatment for rectal cancer. Preoperative radiotherapy interferes with several aspects of urinary and sexual functioning. Bowel dysfunction after LAR is associated with urinary dysfunction and a reduction in sexual desire, activity and satisfaction.

Impact of bowel dysfunction on quality of life after sphincter-preserving resection for rectal cancer.

BACKGROUND: Bowel dysfunction after sphincter-preserving surgery for rectal cancer is a common complication, with the potential to affect quality of life (QoL) strongly. The aim of this study was to examine the extent of bowel dysfunction and impact on health-related QoL after curative sphincter-preserving resection for rectal cancer. METHODS: QoL was assessed using the European Organization for Research and Treatment of Cancer QLQ-C30 questionnaire, and bowel function using a validated questionnaire, including the recently developed low anterior resection syndrome (LARS) score. Assessments were carried out at the time of diagnosis, and at 3 and 12 months after surgery. RESULTS: A total of 260 patients were included in the study. At 3 months, 58·0 per cent of patients had a LARS score of 30 or more (major LARS), which declined to 45·9 per cent at 12 months (P < 0·001). The risk of major LARS was significantly increased in patients who received neoadjuvant therapy (odds ratio 2·41, 95 per cent confidence interval 1·00 to 5·83), and after total versus partial mesorectal excision (odds ratio 2·81, 1·35 to 5·88). Global health status was closely associated with LARS, and significant differences in global health status, functional and symptom scales of QoL were found between patients without LARS and those with major LARS. CONCLUSION: Bowel dysfunction is a major problem with an immense impact on QoL following sphincter-preserving resection. The risk of major LARS was significantly increased after neoadjuvant therapy and total mesorectal excision.

A hyperactive postprandial response in the neorectum--the clue to low anterior resection syndrome after total mesorectal excision surgery?

AIM: To investigate neorectal properties regarding biomechanical, sensory and postprandial response in patients after total mesorectal excision without neoadjuvant radiotherapy in groups of no low anterior resection syndrome (LARS) patients and major LARS patients. METHOD: Patients without LARS (n = 9) and patients with major LARS (n = 23) were investigated by multimodal rectal stimulation and standard anorectal physiological tests, and results were compared. RESULTS: Patients with major LARS had an increased postprandial response with a significant increase in pressure in the neorectum after a meal compared with patients without LARS (P = 0.017). No biomechanical differences could be detected. CONCLUSION: Low anterior resection syndrome seems to be caused by physiological changes due to neural damage more than structural changes in the ano-neorectum.

Bowel dysfunction after low anterior resection with and without neoadjuvant therapy for rectal cancer: a population-based cross-sectional study.

AIM: Bowel dysfunction was assessed after low anterior resection with and without neoadjuvant therapy (NT) for rectal cancer using a novel symptom-based scoring system correlated with quality of life. METHOD: We identified all patients who underwent curative resection for rectal cancer in Denmark between 2001 and 2007. A questionnaire on bowel function and quality of life, including the recently validated low anterior resection syndrome score (LARS score; range 0-42) was administered to recurrence-free patients in 2009. We used multivariate analysis to examine the association between major LARS (LARS score ≥ 30) and a number of patient and treatment-related factors. RESULTS: Of 1087 eligible patients, 980 agreed to participate and, of these, 938 were included in the analysis. Major LARS was observed in 41%. The use of NT (OR = 2.48; 95% CI: 1.73-3.55), long-course chemoradiotherapy vs short-course radiotherapy (OR = 0.90; 95% CI: 0.44-1.87), total mesorectal excision (TME) vs partial mesorectal excision (PME) (OR = 2.31; 95% CI: 1.69-3.16), anastomotic leakage (OR = 2.06; 95% CI: 0.93-4.55), age ≤ 64 years at surgery (OR = 1.90; 95% CI: 1.43-2.51) and female gender (OR = 1.35; 95% CI 1.02-1.79) were associated with major LARS. No association was found between major LARS and the time since surgery (OR = 0.78; 95% CI: 0.59-1.04) or neorectal reconstruction (colonic pouch vs straight colorectal or side-to-end anastomosis (OR = 0.96; 95% CI: 0.63-1.46). CONCLUSION: Severe bowel dysfunction is a frequent long-term outcome after resection for rectal cancer. Use of NT, regardless of a long- or short-course protocol, and TME (compared with PME) are strong independent risk factors for major LARS.

Intestinal microdialysis--applicability, reproducibility and local tissue response in a pig model.

BACKGROUND AND AIMS: Microdialysis has been applied to the intestinal wall for the purpose of monitoring local ischemia. The aim of this study was to investigate the applicability, reproducibility and local response to microdialysis in the intestinal wall. MATERIALS AND METHODS: In 12 pigs two microdialysis probes were inserted into the ileal wall, one in the peritoneal cavity and one in the psoas muscle. Relative recovery was measured for all probes by the no net flux method. Metabolic measurements of glucose, lactate and glycerol were performed over six hours. The ileal wall segments containing the probes were processed for histological examination. RESULTS: Large intra- and inter-group differences in the relative recovery were found between all locations. Absolute values of metabolites showed no significant changes during the study period. The lactate in blood was 25-30% of the intra-tissue values. A severe inflammatory reaction was seen in the ileal wall around all probes. CONCLUSION: Measurement of the relative recovery is essential for valid measurements of metabolites when using microdialysis. The inflammatory reaction around the probe in the intestinal wall is likely to affect metabolism and measurements hereof. Therefore intestinal wall microdialysis seems confined to experimental research, and future studies should consider the intra-peritoneal approach.

Increased platelet reactivity and significant changes in coagulation markers after cavopulmonary connection.

OBJECTIVE: To evaluate platelet reactivity and coagulation markers after surgical palliation of univentricular hearts. DESIGN AND PATIENTS: Cross sectional survey of 24 patients, median age 11 (range 4-22) years, at 2 (range 0.5-6) years after a total cavopulmonary connection (TCPC; n = 14) or a bidirectional Glenn anastomosis (Glenn; n = 10). MAIN OUTCOME MEASURES: Platelet reactivity and/or coagulation markers were measured in 20 patients (four excluded because of anticoagulant treatment) and compared with 33 healthy controls, median age 12 (range 6-16) years. RESULTS: None of the patients had clinically apparent thromboembolic events. However, increased platelet reactivity was observed ex vivo both after collagen induced platelet aggregation (median 73% (interquartile range 61-84%) in patients, and 61% (47-69%) in controls; p < 0.01), and after ADP induced platelet aggregation (69% (53-77%) in patients, and 56% (40-66%) in controls; p < 0.05). Concentrations of protein S antigen, antithrombin III, and protein C activity were reduced after both TCPC and Glenn. A concomitant decrease was seen in coagulation factor II, VII, X, and factor VII clot activity. CONCLUSIONS: Several abnormalities in the coagulation system were observed after bidirectional Glenn anastomosis, similar to alterations previously described in Fontan operated and TCPC patients. Antithrombotic treatment in these patients is still an unresolved issue, but aspirin is often recommended. This study shows that such a strategy is rational and the results suggest that antiplatelet treatment may be advantageous, either alone or in combination with oral anticoagulant treatment.