Risk-factors for nodular hyperplasia of parathyroid glands in sHPT patients.

INTRODUCTION: Nodular hyperplasia of parathyroid glands (PG) is the most probable cause of medical treatment failure in secondary hyperparathyroidism (sHPT). This prospective cohort study is located at the interface of medical and surgical consideration of sHPT treatment options and identifies risk-factors for nodular hyperplasia of PG. MATERIAL AND METHODS: One-hundred-eight resected PG of 27 patients with a broad spectrum of sHPT severity were classified according to the degree of hyperplasia by histopathology. Twenty routinely gathered parameters from medical history, ultrasound findings of PG and laboratory results were analyzed for their influence on nodular hyperplasia of PG by risk-adjusted multivariable binary regression. A prognostic model for non-invasive assessment of PG was developed and used to weight the individual impact of identified risk-factors on the probability of nodular hyperplasia of single PG. RESULTS: Independent risk-factors for nodular hyperplasia of single PG were duration of dialysis in years, PG volume in mm3 determined by ultrasound and serum level of parathyroid hormone in pg/mL. Multivariable analyses computed a model with an Area Under the Receiver Operative Curve of 0.857 (95%-CI:0.773-0.941) when predicting nodular hyperplasia of PG. Theoretical assessment of risk-factor interaction revealed that the duration of dialysis had the strongest influence on the probability of nodular hyperplasia of single PG. CONCLUSIONS: The three identified risk-factors (duration of dialysis, PG volume determined by ultrasound and serum level of parathyroid hormone) can be easily gathered in daily routine and could be used to non-invasively assess the probability of nodular hyperplasia of PG. This assessment would benefit from periodically collected data sets of PG changes during the course of sHPT, so that the choice of medical or surgical sHPT treatment could be adjusted more to the naturally changing type of histological PG lesion on an individually adopted basis in the future.

Risk Balancing of Cold Ischemic Time against Night Shift Surgery Possibly Reduces Rates of Reoperation and Perioperative Graft Loss.

Background. This retrospective cohort study evaluates the advantages of risk balancing between prolonged cold ischemic time (CIT) and late night surgery. Methods. 1262 deceased donor kidney transplantations were analyzed. Multivariable regression was used to determine odds ratios (ORs) for reoperation, graft loss, delayed graft function (DGF), and discharge on dialysis. CIT was categorized according to a forward stepwise pattern ≤1h/>1h, ≤2h/>2h, ≤3h/>3h,…, ≤nh/>nh. ORs for DGF were plotted against CIT and a nonlinear regression function with best R2 was identified. First and second derivative were then implemented into the curvature formula k(x) = f''(x)/(1 + f'(x)2)3/2 to determine the point of highest CIT-mediated risk acceleration. Results. Surgery between 3 AM and 6 AM is an independent risk factor for reoperation and graft loss, whereas prolonged CIT is only relevant for DGF. CIT-mediated risk for DGF follows an exponential pattern f(x) = A · (1 + k · e(I · x)) with a cut-off for the highest risk increment at 23.5 hours. Conclusions. The risk of surgery at 3 AM-6 AM outweighs prolonged CIT when confined within 23.5 hours as determined by a new mathematical approach to calculate turning points of nonlinear time related risks. CIT is only relevant for the endpoint of DGF but had no impact on discharge on dialysis, reoperation, or graft loss.

Liver Transplantation for Hepatocellular Carcinoma: A Single Center Resume Overlooking Four Decades of Experience.

Background. This is a single center oncological resume overlooking four decades of experience with liver transplantation (LT) for hepatocellular carcinoma (HCC). Methods. All 319 LT for HCC that were performed between 1975 and 2011 were included. Predictors for HCC recurrence (HCCR) and survival were identified by Cox regression, Kaplan-Meier analysis, Log Rank, and χ (2)-tests where appropriate. Results. HCCR was the single strongest hazard for survival (exp⁡(B) = 10.156). Hazards for HCCR were tumor staging beyond the histologic MILAN (exp⁡(B) = 3.645), bilateral tumor spreading (exp⁡(B) = 14.505), tumor grading beyond G2 (exp⁡(B) = 8.668), and vascular infiltration of small or large vessels (exp⁡(B) = 11.612, exp⁡(B) = 18.324, resp.). Grading beyond G2 (exp⁡(B) = 10.498) as well as small and large vascular infiltrations (exp⁡(B) = 13.337, exp⁡(B) = 16.737, resp.) was associated with higher hazard ratios for long-term survival as compared to liver transplantation beyond histological MILAN (exp⁡(B) = 4.533). Tumor dedifferentiation significantly correlated with vascular infiltration (χ (2) p = 0.006) and intrahepatic tumor spreading (χ (2) p = 0.016). Conclusion. LT enables survival from HCC. HCC dedifferentiation is associated with vascular infiltration and intrahepatic tumor spreading and is a strong hazard for HCCR and survival. Pretransplant tumor staging should include grading by biopsy, because grading is a reliable and easily accessible predictor of HCCR and survival. Detection of dedifferentiation should speed up the allocation process.

Value of oral effervescent powder administration for multidetector CT evaluation of esophageal cancer.

PURPOSE: To assess the value of oral effervescent powder (EP) for evaluation of esophageal distension, and for detection and staging of esophageal cancer with contrast-enhanced CT. MATERIALS AND METHODS: 84 patients without esophageal pathology and 52 patients with histological confirmed diagnosis of esophageal cancer were included in this prospective IRB-approved study. Half of the patients in both groups received EP prior to CT. Esophageal distension was assessed by planimetry of the inner (IA) and outer area (OA). Two blinded readers evaluated the datasets separately with regard to diagnosis of esophageal cancer (yes/no) and staging (T0-T4), if applicable. Distension results were compared (t-Test). In patients with cancer sensitivity, specificity, NPV and PPV were calculated. CT staging results were compared to histopathology (Cohen-k). RESULTS: IA and IA/OA were significantly larger after EP as compared to the group without EP (p<0.05). Sensitivity, specificity, NPV and PPV for cancer detection cancer were as follows: 78%/78%, 98%/98%, 95%/95%, 87%/87% with EP; 60%/68%, 98%/98%, 94%/94%, 80%/83% without EP. Staging with EP was good (k=0.84/0.67) and moderate without EP (k=0.58/0.59). CONCLUSIONS: Administration of EP prior to CT results in good distension of the esophagus, and improves detection and staging of esophageal cancer, as compared to control studies without EP.

Characterization and staging of central bile duct stenosis--evaluation of the hepatocyte specific contrast agent gadoxetate disodium.

OBJECTIVE: To assess the value of gadoxetate disodium for characterization and staging of central bile duct stenosis (CBDS). MATERIALS AND METHODS: This prospective HIPAA-compliant study was IRB approved. 14 patients (8 male, 6 female; 36-80 years) with clinical suspicion of CBDS underwent preoperative MRI. To estimate the value of hepatocyte phase images (10, 20, 120 min p.i.), only T2w images (T2), only post-contrast images (CM), or both image datasets were assessed in three reading sessions by 3 readers. Agreement of each reading session with the intraoperative findings in terms of CBDS etiology and tumor extension (weighted kappa statistic) was calculated. RESULTS: CBDS was caused by hilar cholangiocarcinoma (n=9), gallbladder carcinoma (n=4) and pancreatic carcinoma (n=1). Characterization of CBDS etiology was correct by use of: T2w images in 57%, 64%, 50%; CM images in 64%, 57%, 50%; both in 71%, 64%, 64%. Agreement comparing reading sessions and intraoperative findings regarding tumor extension was fair up to moderate (κ-range=0.21-0.54) as a result of common underestimation. Interobserver agreement for tumor extension was fair (κ-range=0.31-0.33). CONCLUSIONS: By means of combined evaluation of T2 and CM images a more reliable characterization of CBDS was possible. Even though CBDS tended to be underestimated assessment of exact tumor extension was improved by contrast administration.