Prevalence, one-year-incidence and predictors of carcinoid heart disease.

BACKGROUND: Carcinoid heart disease (CHD) caused by neuroendocrine tumours (NET) is associated with an increased morbidity and mortality due to valvular dysfunction and right sided heart failure. The present study aimed to assess the prevalence and one-year-incidence of CHD in NET patients. Tumour characteristics, laboratory measurements, and echocardiographic findings were evaluated to identify predictors of CHD manifestation. METHODS: The study was an investigator-initiated, monocentric, prospective trial. Patients with NET without previously diagnosed CHD were included and underwent comprehensive gastroenterological and oncological diagnostics. Echocardiographic examinations were performed at baseline and after one year. RESULTS: Forty-seven NET patients were enrolled into the study, 64% of them showed clinical features of a carcinoid syndrome (CS). Three patients presented with CHD at baseline and three patients developed cardiac involvement during the follow-up period corresponding to a prevalence of 6% at baseline and an incidence of 6.8% within one year. Hydroxyindoleacetic acid (5-HIAA) was identified to predict the occurrence of CHD (OR, 1.004; 95% CI, 1.001-1.006 for increase of 5-HIAA), while chromogranin A (CgA), and Kiel antigen 67 (Ki 67%) had no predictive value. Six patients with CHD at twelve-month follow-up revealed a tendency for larger right heart diameters and increased values of myocardial performance index (MPEI) at baseline compared to NET patients. CONCLUSION: The prevalence at baseline and one-year-incidence of CHD was 6-7%. 5-HIAA was identified as the only marker which predict the development of CHD.

Increased Activity of the Immunoregulatory Enzyme Indoleamine-2,3-Dioxygenase with Consecutive Tryptophan Depletion Predicts Death in Patients with Neuroendocrine Neoplasia.

BACKGROUND/AIMS: Data from a considerable number of malignancies demonstrate that depletion of the essential amino acid tryptophan via induction of the immunoregulatory enzyme indoleamine-2,3-dioxygenase (IDO) serves as an important tumour escape strategy and is of prognostic importance. Here we investigate the predictive value of the activity of IDO as well as levels of tryptophan and respective downstream catabolites in a large cohort of patients with neuroendocrine neoplasms (NEN). METHODS: 142 consecutive Caucasian patients (62 male, aged 60.3 ± 11.9 years) with histologically confirmed NEN were systematically analysed in a retrospective blinded end point analysis. Patients were followed up for a mean period of about 3.9 ± 1.9 years. Clinical outcome, levels of established biomarkers, and tryptophan degradation markers (assessed using tandem mass spectrometry) including estimated IDO activity were recorded. Cox proportional hazards regression models were performed for the assessment of prognostic power. RESULTS: We found that baseline tryptophan levels were significantly lower and IDO activity was significantly increased in non-survivors. The risk for death inclined stepwise and was highest in patients in the upper tertile of IDO activity. Cox proportional regression models identified IDO activity as an independent predictor of death. CONCLUSIONS: In this retrospective analysis, we observed that baseline activity of the immunoregulatory enzyme IDO was significantly increased in non-survivors. IDO activity was identified as an independent predictor of death in this cohort of NEN patients. Whether IDO activity or tryptophan depletion serves to guide future therapeutic interventions in NEN remains to be established.

Management of follow-up of neuroendocrine neoplasias.

Neuroendocrine neoplasias (NEN) comprise heterogeneous epithelial neoplasms with a large variety of clinical presentations, treatment options and outcomes. Since potentially all NEN bear malignant potential it is important for long-term clinical management and improvement of outcome to decide on successful and oncologically and economically meaningful follow-up strategies. Evidence-based outcome data validating specific follow-up strategies are, however, not available to date and thus outcome data, known prognostic factors and clinical experience guide the decisions on follow-up regimens. The review summarizes general recommendations as well as specific considerations based on tumor entities, clinicopathological tumor characteristics and clinical experience. Follow-up shall serve the patient to improve outcome, benefit from more effective therapies and suffer less from unnecessary and/or toxic therapeutic interventions and finally preserve or gain a good quality of life.

Maximizing Information From Routine Staging Computed Tomography in Functional Neuroendocrine Neoplasms: Are There Findings Indicating the Presence of Carcinoid Heart Disease?

PURPOSE: The aim of this study was to evaluate signs of right-sided heart dysfunction on staging computed tomography (CT) as indirect indicators of carcinoid heart disease. PATIENTS AND METHODS: Patients with functionally active neuroendocrine neoplasm and different grades of tricuspid valve regurgitation (TR) were identified. Two readers independently reviewed contrast-enhanced staging CT performed within 90 days before or after echocardiography. Logistic regression and receiver operating analyses were used to asses the predictive value of right ventricle-left ventricle ratio (RV-LV ratio), ventricular septal bowing, retrograde contrast filling of the hepatic veins during contrast injection, and time to aortal enhancement greater than 100 Hounsfield units during bolus tracking for TR. RESULTS: Forty-four examinations were evaluated (11 with TR = 0, 16 with TR = 1, 9 with TR = 2, and 8 with TR = 3). Right ventricle-LV ratio was found to predict TR less than or equal to 1 versus TR greater than 1 (P = 0.0188) and TR less than or equal to 1 versus TR equals 2 (P = 0.0082). A prolonged time to aortal enhancement greater than 100 Hounsfield units during bolus tracking predicted TR less than or equal to 1 versus TR greater than 1 (P = 0.0077). Area under the curve for RV-LV ratio was 0.86 when differentiating TR less than or equal to 1 versus TR equals 2. With a cutoff of 1.07, sensitivity was 0.89, and specificity was 0.72. CONCLUSIONS: In patients with functionally active neuroendocrine neoplasm, an RV-LV ratio of more than 1.07 predicted TR with a relatively high sensitivity and moderate specificity and thus could serve as an indicator of subclinical carcinoid heart disease on routine staging CT.

Staged Catheter-Based Valve Treatment of Severe Carcinoid Heart Disease.

PURPOSE: Carcinoid heart disease (CHD) with severe valve destruction represents the major cause of high morbidity and mortality in patients with carcinoid syndrome. In this paper, we present a novel interventional treatment approach and report the first clinical result achieved in a patient with extensive CHD. METHODS AND RESULTS: A woman with an ileal neuroendocrine tumour (G2, Ki67: 5%) presented with severe CHD (NYHA IV) affecting both the pulmonary and the tricuspid valve. First, a balloon-expandable 23-mm Edwards SAPIEN™ was successfully implanted percutaneously into the pulmonary valve. Since no catheter-based techniques were available for the replacement of the native tricuspid valve, we implanted an Edwards SAPIEN 26-mm valve into the vena cava inferior between the right atrium and the ostium of the hepatic veins to reduce abdominal congestion. The implantation was technically successful and completely prevented regurgitation into the vena cava inferior and abdominal veins. After this procedure, the patient's clinical condition improved significantly, and she achieved near-normal exercise tolerance (VO2 max: 24.4 ml O2/kg/min, NYHA II). CONCLUSION: We demonstrated that percutaneous valve implantation may offer a novel, minimally invasive option in high-risk patients with severe CHD.

Systemic changes of tryptophan catabolites via the indoleamine-2,3-dioxygenase pathway in primary cervical cancer.

BACKGROUND/AIM: Induction of tryptophan catabolism is mediated by inflammatory mechanisms including up-regulation of the immunoregulatory enzyme indoleamine-2,3-dioxygenase (IDO). This leads to the formation of mediators collectively referred to as kynurenines. Kynurenines are involved in various diseases such as renal failure, sepsis and cancer. We aimed to investigate whether systemic levels of kynurenines are induced in primary cervical cancer (PCC). PATIENTS AND METHODS: Tryptophan, serotonin, kynurenine, kynurenic acid, quinolinic acid and estimated IDO activity were determined using tandem mass spectrometry for serum samples of 20 PCC patients (mean age: 45.1±11.3 years, FIGO-stage: 1b1-2b) prior to radical abdominal surgery. Data were compared to those from 40 healthy controls. Receiver operating curve (ROC) analyses were performed. RESULTS: Mean tryptophan (22.7±15.1 vs. 18.9±3.5 µM; p=0.27) and kynurenine levels (2.25±0.7 vs. 2.59±0.25 µM; p=0.1) were unchanged in PCC patients when compared to controls. Estimated IDO activity (kynurenine level × 100/tryptophan: 11.8±4.5 vs. 14.1±2.4; p=0.04) and mean levels of kynurenic acid (0.25±0.06 vs. 0.55±0.23 µM; p<0.0001) were significantly lower in PCC patients compared to controls, while mean levels of quinolinic acid (0.35±0.07 vs. 0.24±0.09 µM, p<0.0001) were significantly higher. The ratio of quinolinic acid to kynurenic acid (Q/K) differed significantly between patients with and those without cancer (p<0.0001). When this index was >0.95, the sensitivity and specificity for identification of PCC patients were 100% and 90%, respectively (AUC=0.981, 95% CI=0.907-0.999; positive likelihood ratio +10.0). CONCLUSION: PCC is associated with increased systemic levels of quinolinic acid and reduced levels of kynurenic acid. In our study population, the Q/K allowed identification of PCC patients with a high level of accuracy. The prognostic power and relevance of this novel proposed index remains to be elucidated in further larger prospective studies.

Treatment with granulocyte-macrophage colony-stimulating factor is associated with reduced indoleamine 2,3-dioxygenase activity and kynurenine pathway catabolites in patients with severe sepsis and septic shock.

The immunoregulatory enzyme indoleamine 2,3-dioxygenase (IDO) controls tryptophan metabolism and is induced by pro-inflammatory stimuli. We investigated whether immunostimulatory treatment with granulocyte-macrophage colony-stimulating factor (GM-CSF) influences IDO activity and tryptophan metabolism in sepsis. Thirty-six patients with severe sepsis/septic shock and sepsis-associated immunosuppression (assessed using monocytic human leukocyte antigen-DR (mHLA-DR) expression) were assessed in a controlled trial of GM-CSF or placebo treatment for 8 days. Using tandem mass spectrometry, levels of tryptophan, kynurenine, kynurenic acid, quinolinic acid, 5-hydroxytryptophan, serotonin, and estimated IDO activity were determined in a blinded fashion over a 9-day interval. At baseline, tryptophan and metabolite levels did not differ between the study groups. Although tryptophan levels were unchanged in both groups over the treatment interval (all p>0.8), IDO activity was markedly reduced after GM-CSF treatment (35.4 +/- 21.0 vs 21.6 +/-9.9 (baseline vs day 9), p = 0.02). IDO activity differed significantly between the 2 groups after therapy (p = 0.03). Metabolites downstream of IDO (kynurenine, quinolinic acid, kynurenic acid) were all induced in sepsis and declined in the GM-CSF group, but not in controls. Serotonin pathway metabolites remained unchanged in both groups (all p>0.15). Moreover, IDO activity correlated with procalcitonin (p< 0.0001, r = 0.56) and mHLA-DR levels (p = 0.005, r = -0.28) in the overall samples group. Thus, GM-CSF therapy is associated with decreased IDO activity and reduced kynurenine pathway catabolites in sepsis. This may be due to an improved antibacterial defence.

Granulocyte-macrophage colony-stimulating factor to reverse sepsis-associated immunosuppression: a double-blind, randomized, placebo-controlled multicenter trial.

RATIONALE: Sustained sepsis-associated immunosuppression is associated with uncontrolled infection, multiple organ dysfunction, and death. OBJECTIVES: In the first controlled biomarker-guided immunostimulatory trial in sepsis, we tested whether granulocyte-macrophage colony-stimulating factor (GM-CSF) reverses monocyte deactivation, a hallmark of sepsis-associated immunosuppression (primary endpoint), and improves the immunological and clinical course of patients with sepsis. METHODS: In a prospective, randomized, double-blind, placebo-controlled, multicenter trial, 38 patients (19/group) with severe sepsis or septic shock and sepsis-associated immunosuppression (monocytic HLA-DR [mHLA-DR] <8,000 monoclonal antibodies (mAb) per cell for 2 d) were treated with GM-CSF (4 microg/kg/d) or placebo for 8 days. The patients' clinical and immunological course was followed up for 28 days. MEASUREMENTS AND MAIN RESULTS: Both groups showed comparable baseline mHLA-DR levels (5,609 +/- 3,628 vs. 5,659 +/- 3,332 mAb per cell), which significantly increased within 24 hours in the GM-CSF group. After GM-CSF treatment, mHLA-DR was normalized in 19/19 treated patients, whereas this occurred in 3/19 control subjects only (P < 0.001). GM-CSF also restored ex-vivo Toll-like receptor 2/4-induced proinflammatory monocytic cytokine production. In patients receiving GM-CSF, a shorter time of mechanical ventilation (148 +/- 103 vs. 207 +/- 58 h, P = 0.04), an improved Acute Physiology and Chronic Health Evaluation-II score (P = 0.02), and a shorter length of both intrahospital and intensive care unit stay was observed (59 +/- 33 vs. 69 +/- 46 and 41 +/- 26 vs. 52 +/- 39 d, respectively, both not significant). Side effects related to the intervention were not noted. CONCLUSIONS: Biomarker-guided GM-CSF therapy in sepsis is safe and effective for restoring monocytic immunocompetence. Use of GM-CSF may shorten the time of mechanical ventilation and hospital/intensive care unit stay. A multicenter trial powered for the improvement of clinical parameters and mortality as primary endpoints seems indicated. Clinical trial registered with www.clinicaltrials.gov (NCT00252915).

Increased indoleamine 2,3-dioxygenase (IDO) activity and elevated serum levels of tryptophan catabolites in patients with chronic kidney disease: a possible link between chronic inflammation and uraemic symptoms.

BACKGROUND: Tryptophan (Trp) is catabolized by indoleamine 2,3-dioxygenase (IDO). Changes in Trp metabolism and IDO activity in chronic kidney disease (CKD) have not been widely studied, and the impact of haemodialysis is uncertain. Here we investigate Trp catabolism, IDO activity and the role of inflammation in moderate to very severe CKD and haemodialysis. METHODS: Eighty individuals were included in a prospective blinded endpoint analysis. Using tandem mass spectrometry, serum levels of Trp, kynurenine (Kyn), kynurenic-acid (Kyna), quinolinic-acid (Quin), 5-hydroxytryptophan (OH-Trp), serotonin (5-HT), estimated IDO activity and inflammatory markers were assessed in 40 CKD patients (age 57 +/- 14 years, 21 male, creatinine 4.5 +/- 2.7, n = 17 receiving haemodialysis), and in 40 healthy controls (age 34 +/- 9 years, 26 male). RESULTS: Trp levels were unchanged in CKD (P = 0.78 versus controls). Serum levels of Kyn, Kyna and Quin increased with CKD severity (stages 4, 5 versus controls all P < or = 0.01). IDO activity was significantly induced in CKD and correlated with disease severity (stages 3-5 versus controls, all P < or = 0.01) and inflammatory markers [high-sensitivity C-reactive protein (hsCRP), soluble TNF-receptor-1 (sTNFR-I); both P < or = 0.03]. IDO products (Kyn, Kyna, Quin) correlated also with hsCRP and sTNFR-I (all P < or = 0.04). Haemodialysis did not influence IDO activity (P = 0.26) and incompletely removed Kyn, Kyna, Quin, OH-Trp and 5-HT by 22, 26, 50, 44 and 34%, respectively. In multiple regression, IDO activity correlated with hsCRP and sTNFR-I (both P < or = 0.03) independent of serum creatinine, age and body weight. CONCLUSIONS: IDO activity and serum levels of tryptophan catabolites of the kynurenine pathway increase with CKD severity. In CKD, induction of IDO may primarily be a consequence of chronic inflammation.