Variation in treatment and survival of older patients with non-metastatic breast cancer in five European countries: a population-based cohort study from the EURECCA Breast Cancer Group.

BACKGROUND: Older patients are poorly represented in breast cancer research and guidelines do not provide evidence based recommendations for this specific group. We compared treatment strategies and survival outcomes between European countries and assessed whether variance in treatment patterns may be associated with variation in survival. METHODS: Population-based study including patients aged ≥ 70 with non-metastatic BC from cancer registries from the Netherlands, Belgium, Ireland, England and Greater Poland. Proportions of local and systemic treatments, five-year relative survival and relative excess risks (RER) between countries were calculated. RESULTS: In total, 236,015 patients were included. The proportion of stage I BC receiving endocrine therapy ranged from 19.6% (Netherlands) to 84.6% (Belgium). The proportion of stage III BC receiving no breast surgery varied between 22.0% (Belgium) and 50.8% (Ireland). For stage I BC, relative survival was lower in England compared with Belgium (RER 2.96, 95%CI 1.30-6.72, P < .001). For stage III BC, England, Ireland and Greater Poland showed significantly worse relative survival compared with Belgium. CONCLUSIONS: There is substantial variation in treatment strategies and survival outcomes in elderly with BC in Europe. For early-stage BC, we observed large variation in endocrine therapy but no variation in relative survival, suggesting potential overtreatment. For advanced BC, we observed higher survival in countries with lower proportions of omission of surgery, suggesting potential undertreatment.

A European, Observational Study of Endocrine Therapy Administration in Patients With an Initial Diagnosis of Hormone Receptor-Positive Advanced Breast Cancer.

BACKGROUND: Despite guideline recommendations, reports suggest that a proportion of patients with hormone receptor (HR)-positive locally advanced or metastatic breast cancer (LA/MBC) might not receive endocrine therapy. The aims of this study were to estimate the proportion of postmenopausal patients with an initial (primary) diagnosis of HR-positive LA/MBC in Europe, and to assess the administration of endocrine treatment in these patients. MATERIALS AND METHODS: Fourteen national and regional cancer registries across Europe were invited to participate in this observational study. Six registries each provided anonymized clinical information on > 5000 postmenopausal women with breast cancer diagnosed between January 2000 and December 2014, including age at diagnosis, estrogen and/or progesterone receptor status, disease stage, and receipt of endocrine therapy. The proportion of patients with an initial diagnosis of HR-positive LA/MBC and, of these, the proportion who received endocrine therapy, was calculated. RESULTS: Registries from Belgium, England, Ireland, Norway, The Netherlands, and Munich, Germany provided data. In total, 316,680 postmenopausal women were diagnosed with breast cancer, including 244,268 with known HR status and disease stage. Of these patients, 19,002 (7.8%) had a primary diagnosis of HR-positive LA/MBC. This proportion ranged from 5.4% (N = 4484) in England to 12.7% (N = 4085) in Germany. Most of these patients (n = 14,157; 74.5%) received endocrine treatment, ranging from 55.5% (n = 445) in Norway to 88.1% (n = 443) in Belgium. CONCLUSION: These results indicate that a sizeable proportion of postmenopausal patients in Europe received a primary diagnosis of HR-positive LA/MBC, and that almost three-quarters received subsequent endocrine therapy as per guideline recommendations.

Beneficial Effects of Early Enteral Nutrition After Major Rectal Surgery: A Possible Role for Conditionally Essential Amino Acids? Results of a Randomized Clinical Trial.

OBJECTIVES: To investigate direct postoperative outcome and plasma amino acid concentrations in a study comparing early enteral nutrition versus early parenteral nutrition after major rectal surgery. Previously, it was shown that a low plasma glutamine concentration represents poor prognosis in ICU patients. DESIGN: A preplanned substudy of a previous prospective, randomized, open-label, single-centre study, comparing early enteral nutrition versus early parenteral nutrition in patients at high risk of postoperative ileus after surgery for locally advanced or locally recurrent rectal cancer. Early enteral nutrition reduced postoperative ileus, anastomotic leakage, and hospital stay. SETTING: Tertiary referral centre for locally advanced and recurrent rectal cancer. PATIENTS: A total of 123 patients with locally advanced or recurrent rectal carcinoma requiring major rectal surgery. INTERVENTIONS: Patients were randomized (ALEA web-based external randomization) preoperatively into two groups: early enteral nutrition (early enteral nutrition, intervention) by nasojejunal tube (n = 61) or early parenteral nutrition (early parenteral nutrition, control) by jugular vein catheter (n = 62). Eight hours after the surgical procedure artificial nutrition was started in hemodynamically stable patients, stimulating oral intake in both groups. Blood samples were collected to measure plasma glutamine, citrulline, and arginine concentrations using a validated ultra performance liquid chromatography-tandem mass spectrometric method. MEASUREMENTS AND MAIN RESULTS: Baseline concentrations were comparable for both groups. Directly after rectal surgery, a decrease in plasma amino acids was observed. Plasma glutamine concentrations were higher in the parenteral group than in the enteral group on postoperative day 1 (p = 0.027) and day 5 (p = 0.008). Arginine concentrations were also significantly increased in the parenteral group at day 1 (p < 0.001) and day 5 (p = 0.001). CONCLUSIONS: Lower plasma glutamine and arginine concentrations were measured in the enteral group, whereas a better clinical outcome was observed. We conclude that plasma amino acids do not provide a causal explanation for the observed beneficial effects of early enteral feeding after major rectal surgery.

Variations in compliance to quality indicators by age for 41,871 breast cancer patients across Europe: a European Society of Breast Cancer Specialists database analysis.

OBJECTIVE: The aim of this study is to assess age-specific compliance to quality indicators (QIs) regarding the treatment of breast cancer as defined by European Society of Breast Cancer Specialists (EUSOMA) for patients across Europe. METHODS: All patients entered into this study were affected by in situ or invasive breast cancer, diagnosed and treated between 2003 and 2012 at 27 Breast Units across Europe, who were entered into the EUSOMA database. Patients were categorised according to age; compliance to thirteen QIs was assessed for each age group and per time period (2003-2007 and 2008-2012). Compliance to QIs was tested by multivariable logistic regression models adjusted for breast unit, incidence year and tumour characteristics. RESULTS: Overall, 41,871 patients with a mean age of 59.6years were available for analysis. The highest compliance was reached for patients aged 55-64years and in the time period 2008-2012, whilst the lowest compliance was observed for women aged over 74 or under 40years and in the earlier time period. In multivariable logistic regression models, a significant difference between age categories was shown for 12 out of 13 QIs (P<0.001). Compliance to the QIs for patients aged ⩾75years was significantly lower when compared to patients aged 55-64years for ten QIs, whilst for patients in the youngest age group this was true for seven QIs. CONCLUSION: In conclusion, we found that among the 27 included breast units across Europe, compliance to QIs for breast cancer treatment is often lower in the youngest and oldest breast cancer patients, with a tendency to overtreatment in the youngest patients, and to under-treatment in the elderly.

Treatment strategies and survival of older breast cancer patients - an international comparison between the Netherlands and Ireland.

OBJECTIVES: Forty percent of breast cancers occur among older patients. Unfortunately, there is a lack of evidence for treatment guidelines for older breast cancer patients. The aim of this study is to compare treatment strategy and relative survival for operable breast cancer in the elderly between The Netherlands and Ireland. MATERIAL AND METHODS: From the Dutch and Irish national cancer registries, women aged ≥65 years with non-metastatic breast cancer were included (2001-2009). Proportions of patients receiving guideline-adherent locoregional treatment, endocrine therapy, and chemotherapy were calculated and compared between the countries by stage. Secondly, 5-year relative survival was calculated by stage and compared between countries. RESULTS: Overall, 41,055 patients from The Netherlands and 5,826 patients from Ireland were included. Overall, more patients received guideline-adherent locoregional treatment in The Netherlands, overall (80% vs. 68%, adjusted p<0.001), stage I (83% vs. 65%, p<0.001), stage II (80% vs. 74%, p<0.001) and stage III (74% vs. 57%, P<0.001) disease. On the other hand, more systemic treatment was provided in Ireland, where endocrine therapy was prescribed to 92% of hormone receptor-positive patients, compared to 59% in The Netherlands. In The Netherlands, only 6% received chemotherapy, as compared 24% in Ireland. But relative survival was poorer in Ireland (5 years relative survival 89% vs. 83%), especially in stage II (87% vs. 85%) and stage III (61% vs. 58%) patients. CONCLUSION: Treatment for older breast cancer patients differed significantly on all treatment modalities between The Netherlands and Ireland. More locoregional treatment was provided in The Netherlands, and more systemic therapy was provided in Ireland. Relative survival for Irish patients was worse than for their Dutch counterparts. This finding should be a strong recommendation to study breast cancer treatment and survival internationally, with the ultimate goal to equalize the survival rates for breast cancer patients across Europe.

Colorectal cancer.

Colorectal cancer had a low incidence several decades ago. However, it has become a predominant cancer and now accounts for approximately 10% of cancer-related mortality in western countries. The 'rise' of colorectal cancer in developed countries can be attributed to the increasingly ageing population, unfavourable modern dietary habits and an increase in risk factors, such as smoking, low physical exercise and obesity. New treatments for primary and metastatic colorectal cancer have emerged, providing additional options for patients; these treatments include laparoscopic surgery for primary disease, more-aggressive resection of metastatic disease (such as liver and pulmonary metastases), radiotherapy for rectal cancer, and neoadjuvant and palliative chemotherapies. However, these new treatment options have had limited impact on cure rates and long-term survival. For these reasons, and the recognition that colorectal cancer is long preceded by a polypoid precursor, screening programmes have gained momentum. This Primer provides an overview of the current state of the art of knowledge on the epidemiology and mechanisms of colorectal cancer, as well as on diagnosis and treatment.

Involving patients in a multidisciplinary European consensus process and in the development of a 'patient summary of the consensus document for colon and rectal cancer care'.

CONTEXT: High-quality cancer care should be accessible for patients and healthcare professionals. Involvement of patients as partners in guideline formation and consensus processes is still rarely found. EURECCA, short for European Registration of Cancer Care, is the platform to improve outcomes of cancer care by reducing variation in the diagnostic and treatment process. EURECCA acknowledges the important role of patients in implementation of consensus information in clinical practice. OBJECTIVE: The aim of this article is to describe the process of involving patients in the consensus process and in developing the patient summary of the consensus for colon and rectal cancer care. METHODS: The Delphi method for achieving consensus was used. Three online voting rounds and one tele-voting round were offered to an expert panel of oncology professionals and patient representatives. At four different stages, patients and/or patient representatives were involved in the process: (1) during the consensus process, (2) lecturing about the role of the patient, (3) development of the patient summary, and (4) testing the patient summary. RESULTS: Representatives were invited to the voting and commenting rounds of this process and given an equal vote. Although patients were not consulted during the planning stages of this process, patient involvement increased following the panel's discussion of the implementation of the consensus among the patient population. After the consensus meeting, the patient summary was written by patient representatives, oncologists and nurses. A selection of proactive patients reviewed the draft patient summary; responses were positive and several patient-reported outcomes were added. Questionnaires to evaluate the use and implementation of the patient summary in daily practice are currently being developed and tested. Patient consultation will be needed in future planning for selection of topics. DISCUSSION: The present study may function as a model for future consensus processes to involve patients at different stages and to implement both patient and healthcare professional versions in daily practice.

Reduction of postoperative ileus by early enteral nutrition in patients undergoing major rectal surgery: prospective, randomized, controlled trial.

BACKGROUND: The current trend in postoperative nutrition is to promote a normal oral diet as early as possible. However, postoperative ileus is a frequent and common problem after major abdominal surgery. This study was designed to investigate whether early enteral nutrition (EEN), as a bridge to a normal diet, can reduce postoperative ileus. METHODS: Patients undergoing major rectal surgery for locally advanced primary or recurrent rectal carcinoma (after neoadjuvant (chemo)-radiation, with or without intraoperative radiotherapy) were randomly assigned to EEN (n = 61) or early parenteral nutrition (EPN, n = 62) in addition to an oral diet. Early nutrition was started 8 hours after surgery. Early parenteral nutrition was given as control nutrition to obtain caloric equivalence and minimize confounding. The primary endpoint was time to first defecation; secondary outcomes were morbidity, other ileus symptoms, and length of hospital stay. RESULTS: Baseline characteristics were similar for both groups. In intention-to-treat analysis, the time to first defecation was significantly shorter in the enteral nutrition arm than in the control arm (P = 0.04). Moreover, anastomotic leakage occurred significantly less frequently in the enteral group (1 patient) compared with parenteral supplementation (9 patients, P = 0.009). Mean length of stay in the enteral group was 13.4 ± 2.2 days versus 16.7 ± 2.3 days in the parenteral group (P = 0.007). CONCLUSIONS: Early enteral nutrition is safe and associated with significantly less ileus. Early enteral nutrition is associated with less anastomotic leakage in patients undergoing extensive rectal surgery.

EURECCA colorectal: multidisciplinary management: European consensus conference colon & rectum.

BACKGROUND: Care for patients with colon and rectal cancer has improved in the last 20years; however considerable variation still exists in cancer management and outcome between European countries. Large variation is also apparent between national guidelines and patterns of cancer care in Europe. Therefore, EURECCA, which is the acronym of European Registration of Cancer Care, is aiming at defining core treatment strategies and developing a European audit structure in order to improve the quality of care for all patients with colon and rectal cancer. In December 2012, the first multidisciplinary consensus conference about cancer of the colon and rectum was held. The expert panel consisted of representatives of European scientific organisations involved in cancer care of patients with colon and rectal cancer and representatives of national colorectal registries. METHODS: The expert panel had delegates of the European Society of Surgical Oncology (ESSO), European Society for Radiotherapy & Oncology (ESTRO), European Society of Pathology (ESP), European Society for Medical Oncology (ESMO), European Society of Radiology (ESR), European Society of Coloproctology (ESCP), European CanCer Organisation (ECCO), European Oncology Nursing Society (EONS) and the European Colorectal Cancer Patient Organisation (EuropaColon), as well as delegates from national registries or audits. Consensus was achieved using the Delphi method. For the Delphi process, multidisciplinary experts were invited to comment and vote three web-based online voting rounds and to lecture on the subjects during the meeting (13th-15th December 2012). The sentences in the consensus document were available during the meeting and a televoting round during the conference by all participants was performed. This manuscript covers all sentences of the consensus document with the result of the voting. The consensus document represents sections on diagnostics, pathology, surgery, medical oncology, radiotherapy, and follow-up where applicable for treatment of colon cancer, rectal cancer and metastatic colorectal disease separately. Moreover, evidence based algorithms for diagnostics and treatment were composed which were also submitted to the Delphi process. RESULTS: The total number of the voted sentences was 465. All chapters were voted on by at least 75% of the experts. Of the 465 sentences, 84% achieved large consensus, 6% achieved moderate consensus, and 7% resulted in minimum consensus. Only 3% was disagreed by more than 50% of the members. CONCLUSIONS: Multidisciplinary consensus on key diagnostic and treatment issues for colon and rectal cancer management using the Delphi method was successful. This consensus document embodies the expertise of professionals from all disciplines involved in the care for patients with colon and rectal cancer. Diagnostic and treatment algorithms were developed to implement the current evidence and to define core treatment guidance for multidisciplinary team management of colon and rectal cancer throughout Europe.

EURECCA consensus conference highlights about rectal cancer clinical management: the radiation oncologist's expert review.

BACKGROUND AND PURPOSE: Although rectal and colon cancer management has progressed greatly in the last few decades clinical outcomes still need to be optimized. Furthermore, consensus is required on several issues as some of the main international guidelines provide different recommendations. The European Registration of Cancer Care (EURECCA) drew up documents to standardize management and care in Europe and aid in decision-making. MATERIAL AND METHODS: In the present section the panel of experts reviews and discusses data from the literature on rectal cancer, focusing on recommendations for selecting between short-course radiotherapy (SCRT) and long-course radio-chemotherapy (LCRTCT) as preoperative treatment as well as on the controversies about adjuvant treatment in patients who had received a pre-operative treatment. RESULTS: The starting-point of the present EURECCA document is that adding SCRT or LCRTCT to TME improved loco-regional control but did not increase overall survival in any single trial which, in any case, had improved with the introduction of total mesorectal excision (TME) into clinical practice. Moderate consensus was achieved for cT3 anyNM0 disease. In this frame, agreement was reached on either SCRT followed by immediate surgery or LCRTCT with delayed surgery for mesorectal fascia (MRF) negative tumors at presentation. LCRTCT was recommended for tumor shrinkage in MRF+ at presentations but if patients were not candidates for chemotherapy, SCRT with delayed surgery is an option/alternative. LCRTCT was recommended for cT4 anycNM0. SCRT offers the advantages of less acute toxicity and lower costs, and LCRTCT tumor shrinkage and down-staging, with 13-36% pathological complete response (pCR) rates. To improve the efficacy of preoperative treatment both SCRT and LCRTCT have been, or are being, associated with diverse schedules of chemotherapy and even new targeted therapies but without any definitive evidence of benefit. Nowadays, standard treatment is fluoropyrimidine alone since alternative agents and regimens have not been shown to be more active, only more toxic. CONCLUSIONS: The EURECCA panel summarized available evidence in an attempt to reduce variance in rectal cancer management. This is expected to benefit patients. Results from ongoing randomized trials will help clarify some of the issues that are still under debate.

EURECCA colorectal: multidisciplinary mission statement on better care for patients with colon and rectal cancer in Europe.

BACKGROUND: Care for patients with colon and rectal cancer has improved in the last twenty years however still considerable variation exists in cancer management and outcome between European countries. Therefore, EURECCA, which is the acronym of European Registration of cancer care, is aiming at defining core treatment strategies and developing a European audit structure in order to improve the quality of care for all patients with colon and rectal cancer. In December 2012 the first multidisciplinary consensus conference about colon and rectum was held looking for multidisciplinary consensus. The expert panel consisted of representatives of European scientific organisations involved in cancer care of patients with colon and rectal cancer and representatives of national colorectal registries. METHODS: The expert panel had delegates of the European Society of Surgical Oncology (ESSO), European Society for Radiotherapy & Oncology (ESTRO), European Society of Pathology (ESP), European Society for Medical Oncology (ESMO), European Society of Radiology (ESR), European Society of Coloproctology (ESCP), European CanCer Organisation (ECCO), European Oncology Nursing Society (EONS) and the European Colorectal Cancer Patient Organisation (EuropaColon), as well as delegates from national registries or audits. Experts commented and voted on the two web-based online voting rounds before the meeting (between 4th and 25th October and between the 20th November and 3rd December 2012) as well as one online round after the meeting (4th-20th March 2013) and were invited to lecture on the subjects during the meeting (13th-15th December 2012). The sentences in the consensus document were available during the meeting and a televoting round during the conference by all participants was performed. All sentences that were voted on are available on the EURECCA website www.canceraudit.eu. The consensus document was divided in sections describing evidence based algorithms of diagnostics, pathology, surgery, medical oncology, radiotherapy, and follow-up where applicable for treatment of colon cancer, rectal cancer and stage IV separately. Consensus was achieved using the Delphi method. RESULTS: The total number of the voted sentences was 465. All chapters were voted on by at least 75% of the experts. Of the 465 sentences, 84% achieved large consensus, 6% achieved moderate consensus, and 7% resulted in minimum consensus. Only 3% was disagreed by more than 50% of the members. CONCLUSIONS: It is feasible to achieve European Consensus on key diagnostic and treatment issues using the Delphi method. This consensus embodies the expertise of professionals from all disciplines involved in the care for patients with colon and rectal cancer. Diagnostic and treatment algorithms were developed to implement the current evidence and to define core treatment guidance for multidisciplinary team management of colon and rectal cancer throughout Europe.

Accurate perioperative flow measurement of the portal vein and hepatic and renal artery: a role for preoperative MRI?

BACKGROUND: Quantification of abdominal blood flow is essential for a variety of gastrointestinal and hepatic topics such as liver transplantation or metabolic flux measurement, but those need to be performed during surgery. It is not clear whether Duplex Doppler Ultrasound during surgery or MRI before surgery is the tool to choose. OBJECTIVE: To examine whether preoperative evaluation of abdominal blood flow using MRI could prove to be a useful and reliable alternative for the perioperative sonographic approach. METHODS: In this study portal and renal venous flow and hepatic arterial flow were sequentially quantified by preoperative MRI, preoperative and perioperative Duplex Doppler Ultrasound (DDUS). 55 Patients scheduled for major abdominal surgery were studied and methods and settings were compared. Additionally, average patient population values were compared. RESULTS: Mean (±SD) plasmaflow measured by perioperative DDUS, preoperative DDUS and MRI, respectively was 433±200/423±162/507±96 ml/min (portal vein); 96±70/74±41/108±91 ml/min (hepatic artery); 248±139/201±118/219±69 ml/min (renal vein). No differences between the different settings of DDUS measurement were detected. Equality of mean was observed for all measurements. Bland Altman Plots showed widespread margins. Hepatic arterial flow measurements correlated with each other, but portal and renal venous flow correlations were absent. CONCLUSIONS: Surgery and method (DDUS vs. MRI) do not affect mean flow values. Individual comparison is restricted due to wide range in measurements. Since MRI proves to be more reliable with respect to inter-observer variability, we recommend using mean MRI results in experimental setups.

Antioxidant-enriched enteral nutrition and immuno-inflammatory response after major gastrointestinal tract surgery.

Major surgery induces an immuno-inflammatory response accompanied by oxidative stress that may impair cellular function and delay recovery. The objective of the study was to investigate the effect of an enteral supplement, containing glutamine and antioxidants, on circulating levels of immuno-inflammatory markers after major gastrointestinal tract surgery. Patients (n 21) undergoing major gastrointestinal tract surgery were randomised in a single-centre, open-label study. The effects on circulating levels of immuno-inflammatory markers were determined on the day before surgery and on days 1, 3, 5 and 7 after surgery. Major gastrointestinal surgery increased IL-6, TNF receptor 55/60 (TNF-R55) and C-reactive protein (CRP). Surgery reduced human leucocyte antigen-DR (HLA-DR) expression on monocytes. CRP decrease was more pronounced in the first 7 d in the treatment group compared with the control group. In the treatment group, from the moment Module AOX was administered on day 1 after surgery, TNF receptor 75/80 (TNF-R75) level decreased until the third post-operative day and then stabilised, whereas in the control group the TNF-R75 level continued to increase. The results of the present pilot study suggest that enteral nutrition enriched with glutamine and antioxidants possibly moderates the immuno-inflammatory response (CRP, TNF-R75) after surgery.

Enteral administration of alanyl-[2-(15)N]glutamine contributes more to the de novo synthesis of arginine than does intravenous infusion of the dipeptide in humans.

BACKGROUND: We previously confirmed in humans the existence of a pathway of glutamine into citrulline and arginine, which is preferentially stimulated by luminally provided glutamine. However, because glutamine is unstable, we tested this pathway with a stable dipeptide of glutamine. OBJECTIVES: The objectives were to explore whether alanyl-glutamine contributes to the synthesis of arginine in humans and whether this depends on the route of administration. DESIGN: The study was conducted under postabsorptive conditions during surgery. Sixteen patients received alanyl-[2-(15)N]glutamine enterally or intravenously together with intravenously administered stable-isotope tracers of citrulline and arginine. Blood was collected from an artery, the portal vein, a hepatic vein, and the right renal vein. Arterial and venous enrichments and (tracer) net balances of alanyl-glutamine and glutamine, citrulline, and arginine across the portal-drained viscera, liver, and kidneys were determined. Parametric tests were used to test results (mean +/- SEM). P < 0.05 was considered significant. RESULTS: Twice as much exogenous glutamine was used for the synthesis of citrulline when alanyl-glutamine was provided enterally (5.9 +/- 0.6%) than when provided intravenously (2.8 +/- 0.3%) (P < 0.01). Consequently, twice as much exogenous glutamine was used for the synthesis of arginine when alanyl-glutamine was provided enterally (5 +/- 0.7%) than when provided intravenously (2.4 +/- 0.2%) (P < 0.01). However, results at the organ level did not explain the differences due to route of administration. CONCLUSIONS: Alanyl-glutamine contributes to the de novo synthesis of arginine, especially when provided enterally. A stable-isotope study using a therapeutic dose of alanyl-glutamine is needed to investigate the clinical implications of this finding.

Antioxidant enriched enteral nutrition and oxidative stress after major gastrointestinal tract surgery.

AIM: To investigate the effects of an enteral supplement containing antioxidants on circulating levels of antioxidants and indicators of oxidative stress after major gastrointestinal surgery. METHODS: Twenty-one patients undergoing major upper gastrointestinal tract surgery were randomised in a single centre, open label study on the effect of postoperative enteral nutrition supplemented with antioxidants. The effect on circulating levels of antioxidants and indicators of oxidative stress, such as F2-isoprostane, was studied. RESULTS: The antioxidant enteral supplement showed no adverse effects and was well tolerated. After surgery a decrease in the circulating levels of antioxidant parameters was observed. Only selenium and glutamine levels were restored to pre-operative values one week after surgery. F2-isoprostane increased in the first three postoperative days only in the antioxidant supplemented group. Lipopolysaccharide binding protein (LBP) levels decreased faster in the antioxidant group after surgery. CONCLUSION: Despite lower antioxidant levels there was no increase in the circulating markers of oxidative stress on the first day after major abdominal surgery. The rise in F2-isoprostane in patients receiving the antioxidant supplement may be related to the conversion of antioxidants to oxidants which raises questions on antioxidant supplementation. Module AOX restored the postoperative decrease in selenium levels. The rapid decrease in LBP levels in the antioxidant group suggests a possible protective effect on gut wall integrity. Further studies are needed on the role of oxidative stress on outcome and the use of antioxidants in patients undergoing major abdominal surgery.

Glutamine is an important precursor for de novo synthesis of arginine in humans.

BACKGROUND: A metabolic relation exists between glutamine and arginine, 2 amino acids with properties that enhance the recovery of seriously ill patients. It is possible that glutamine exerts part of its beneficial effects by enhancing the availability of arginine. OBJECTIVES: We aimed to quantify under postabsorptive conditions the metabolic pathway of plasma glutamine into arginine via the intermediate citrulline and to establish the contribution of the kidneys to the synthesis of arginine. DESIGN: The study was conducted in patients during surgery. The metabolism of glutamine, citrulline, and arginine was studied by using intravenous administration of stable isotope tracers of the amino acids. Results were interpreted by using established equations. Parametric tests were used to test and correlate results. P < 0.05 was regarded as significant. RESULTS: Mean (+/-SE) whole-body plasma turnover rates of glutamine, citrulline, and arginine were 240 +/- 14, 6.2 +/- 0.6, and 42 +/- 2.9 micromol x kg(-1) x h(-1), respectively (P < 0.01). Plasma turnover of citrulline derived from glutamine was shown to be 5.1 +/- 0.7 micromol x kg(-1) x h(-1), and arginine derived from citrulline was shown to be 4.9 +/- 0.9 micromol x kg(-1) x h(-1) (P < 0.01). The contribution of plasma glutamine to plasma arginine derived from plasma citrulline was calculated to be 64%. The kidneys were observed to take up >50% of circulating plasma citrulline and to release equimolar amounts of arginine into plasma. CONCLUSIONS: This study shows that glutamine is an important precursor for the synthesis of arginine in humans. It also provides a firm basis for future studies exploring the effect of a treatment dose and the route of administration (enteral or parenteral) of glutamine.

Specific amino acids in the critically ill patient--exogenous glutamine/arginine: a common denominator?

OBJECTIVE: Glutamine and arginine are both used as nutritional supplements in critically ill patients. Although glutamine has been shown to be beneficial for the metabolically stressed patient, considerations about arginine supplementation are not unanimously determined. Our aim is to review the current knowledge on the possible interplay between glutamine and arginine generation in the stressed patient and to elaborate on whether these amino acids may function as a common denominator. Because glutamine can be given by the parenteral and enteral routes, possible different actions on the metabolic fate (e.g., generation of citrulline) with both routes are analyzed. DATA SOURCE: A summary of data on the clinical effect of glutamine and arginine metabolism is given, incorporating data on glutamine and arginine supplementation. Differences between the route of administration, parenteral or enteral, and the molecular form of supplied glutamine, free or as dipeptide, on citrulline generation by the gut and production of arginine are discussed. RESULTS: Glutamine and arginine influence similar organ systems; however, they differ in their targets. For example, glutamine serves as fuel for the immune cells, increases human leukocyte antigen-DR expression on monocytes, enhances neutrophil phagocytosis, and increases heat shock protein expression. Arginine affects the immune system by stimulating direct or indirect proliferation of immune cells. This indirect effect is possibly mediated by nitric oxide, which also enhances macrophage cytotoxicity. Furthermore, glutamine serves as a precursor for the de novo production of arginine through the citrulline-arginine pathway. Glutamine has shown to be beneficial in the surgical and critically ill patient, whereas arginine supplementation is still under debate. The route of glutamine administration (parenteral or enteral) determines the effect on citrulline and on the de novo arginine generation. There is a marked difference between the administration of free glutamine and dipeptide enterally or parenterally. Splanchnic extraction of the hydrolyzed glutamine in mice when administering the dipeptide enterally is higher compared with administering free glutamine from the enteral site. In patients, splanchnic extraction of the dipeptide given enterally is 100% when comparing supplementation of the dipeptide intravenously. CONCLUSIONS: The beneficial effects of free glutamine or dipeptide may depend on the route of administration but also on the metabolic fate of amino acids generated (e.g., citrulline, arginine). Glutamine serves as a substrate for de novo citrulline and arginine synthesis. More research needs to be done to establish the direct clinical relevance of the different metabolic pathways. Future perspectives might include combining enteral and parenteral routes of administrating free glutamine or dipeptide.

The route of administration (enteral or parenteral) affects the conversion of isotopically labeled L-[2-15N]glutamine into citrulline and arginine in humans.

BACKGROUND: Glutamine exhibits numerous beneficial effects in experimental and clinical studies. It has been suggested that these effects may be partly mediated by the conversion of glutamine into citrulline and arginine. The intestinal metabolism of glutamine appears to be crucial in this pathway. The present study was designed to establish the effect of the feeding route, enteral or parenteral, on the conversion of exogenously administered glutamine into citrulline and arginine at an organ level in humans, with a focus on gut metabolism. METHODS: Sixteen patients undergoing upper gastrointestinal surgery received an IV or enteral (EN) infusion of L-[2-(15)N]glutamine. Blood was sampled from a radial artery and from the portal and right renal vein. Amino acid concentrations and enrichments were measured, and net fluxes of [(15)N]-labeled substrates across the portal drained viscera (PDV) and kidneys were calculated from arteriovenous differences and plasma flow. RESULTS: Arterial [(15)N]glutamine enrichments were significantly lower during enteral tracer infusion (tracer-to-tracee ratio [labeled vs unlabeled substrate, TTR%] IV: 6.66 +/- 0.35 vs EN: 3.04 +/- 0.45; p < .01), reflecting first-pass intestinal metabolism of glutamine during absorption. Compared with IV administration, enteral administration of the glutamine tracer resulted in a significantly higher intestinal fractional extraction of [(15)N]glutamine (IV: 0.15 +/- 0.03 vs EN: 0.44 +/- 0.08 micromol/kg/h; p < .01). Furthermore, enteral administration of the glutamine tracer resulted in higher arterial enrichments of [(15)N]citrulline (TTR% IV: 5.52 +/- 0.44 vs EN: 8.81 +/- 1.1; p = .02), and both routes of administration generated a significant enrichment of [(15)N]arginine (TTR% IV: 1.43 +/- 0.12 vs EN: 1.68 +/- 0.18). This was accompanied by intestinal release of [(15)N]citrulline across the PDV, which was higher with enteral glutamine (IV: 0.38 +/- 0.07 vs EN: 0.72 +/- 0.11 micromol/kg/h; p = .02), and subsequent [(15)N]arginine release in both groups. CONCLUSIONS: In humans, the gut preferably takes up enterally administered glutamine compared with intravenously provided glutamine. The route of administration, enteral or IV, affects the quantitative conversion of glutamine into citrulline and subsequent renal arginine synthesis in humans.

Intestinal and hepatic metabolism of glutamine and citrulline in humans.

Glutamine plays an important role in nitrogen homeostasis and intestinal substrate supply. It has been suggested that glutamine is a precursor for arginine through an intestinal-renal pathway involving inter-organ transport of citrulline. The importance of intestinal glutamine metabolism for endogenous arginine synthesis in humans, however, has remained unaddressed. The aim of this study was to investigate the intestinal conversion of glutamine to citrulline and the effect of the liver on splanchnic citrulline metabolism in humans. Eight patients undergoing upper gastrointestinal surgery received a primed continuous intravenous infusion of [2-(15)N]glutamine and [ureido-(13)C-(2)H(2)]citrulline. Arterial, portal venous and hepatic venous blood were sampled and portal and hepatic blood flows were measured. Organ specific amino acid uptake (disposal), production and net balance, as well as whole body rates of plasma appearance were calculated according to established methods. The intestines consumed glutamine at a rate that was dependent on glutamine supply. Approximately 13% of glutamine taken up by the intestines was converted to citrulline. Quantitatively glutamine was the only important precursor for intestinal citrulline release. Both glutamine and citrulline were consumed and produced by the liver, but net hepatic flux of both amino acids was not significantly different from zero. Plasma glutamine was the precursor of 80% of plasma citrulline and plasma citrulline in turn was the precursor of 10% of plasma arginine. In conclusion, glutamine is an important precursor for the synthesis of arginine after intestinal conversion to citrulline in humans.