Azacitidine in 302 patients with WHO-defined acute myeloid leukemia: results from the Austrian Azacitidine Registry of the AGMT-Study Group

Data on efficacy and safety of azacitidine in acute myeloid leukemia (AML) with >30 % bone marrow (BM) blasts are limited, and the drug can only be used off-label in these patients. We previously reported on the efficacy and safety of azacitidine in 155 AML patients treated within the Austrian Azacitidine Registry (clinicaltrials.gov identifier NCT01595295). We herein update this report with a population almost twice as large (n = 302). This cohort included 172 patients with >30 % BM blasts; 93 % would have been excluded from the pivotal AZA-001 trial (which led to European Medicines Agency (EMA) approval of azacitidine for high-risk myelodysplastic syndromes (MDS) and AML with 20-30 % BM blasts). Despite this much more unfavorable profile, results are encouraging: overall response rate was 48 % in the total cohort and 72 % in patients evaluable according to MDS-IWG-2006 response criteria, respectively. Median OS was 9.6 (95 % CI 8.53-10.7) months. A clinically relevant OS benefit was observed with any form of disease stabilization (marrow stable disease (8.1 months), hematologic improvement (HI) (9.7 months), or the combination thereof (18.9 months)), as compared to patients without response and/or without disease stabilization (3.2 months). Age, white blood cell count, and BM blast count at start of therapy did not influence OS. The baseline factors LDH >225 U/l, ECOG ≥2, comorbidities ≥3, monosomal karyotype, and prior disease-modifying drugs, as well as the response-related factors hematologic improvement and further deepening of response after first response, were significant independent predictors of OS in multivariate analysis. Azacitidine seems effective in WHO-AML, including patients with >30 % BM blasts (currently off-label use). Although currently not regarded as standard form of response assessment in AML, disease stabilization and/or HI should be considered sufficient response to continue treatment with azacitidine.

Applicability of non-destructive substitutes for leaf area in different stands of Norway spruce (Picea abies L. Karst.) focusing on traditional forest crown measures

Since individual tree leaf area is an important measure for productivity as well as for site occupancy, it is of high interest in many studies about forest growth. The exact determination of leaf area is nearly impossible. Thus, a common way to get information about leaf area is to use substitutes. These substitutes are often variables which are collected in a destructive way which is not feasible for long term studies. Therefore, this study aimed at testing the applicability of using substitutes for leaf area which could be collected in a non-destructive way, namely crown surface area and crown projection area. In 8 stands of Norway spruce (Picea abies L. Karst.), divided into three age classes and two thinning treatments, a total of 156 trees were felled in order to test the relationship between leaf area and crown surface area and crown projection area, respectively. Individual tree leaf area of the felled sample trees was estimated by 3P-branch sampling with an accuracy of ±10%. Crown projection area and crown surface area were compared with other, more commonly used, but destructive predictors of leaf area, namely sapwood area at different heights on the bole. Our investigations confirmed findings of several studies that sapwood area is the most precise measure for leaf area because of the high correlation between sapwood area and the leaf area. But behind sapwood area at crown base and sapwood area at three tenth of the tree height the predictive ability of crown surface area was ranked third and even better than that of sapwood area at breast height (R(2) = 0.656 compared with 0.600). Within the stands leaf area is proportional to crown surface area. Using the pooled data of all stands a mixed model approach showed that additionally to crown surface area dominant height and diameter at breast height (dbh) improved the leaf area estimates. Thus, taking dominant height and dbh into account, crown surface area can be recommended for estimating the leaf area of individual trees. The resulting model was in line with many other findings on the leaf area and leaf mass relationships with crown size. From the additional influence of dominant height and dbh in the leaf area model we conclude that the used crown model could be improved by estimating the position of the maximum crown width and the crown width at the base of the crown depending on these two variables.

Impact of interobserver disagreement on phenotype-genotype associations in Crohn's disease

BACKGROUND

Nonvalidated definitions of disease-related parameters in inflammatory bowel disease cause variations in diagnosis and disease classification. We determined interobserver agreement on applications of definitions of the Vienna Classification variables and computed the potential influence of misclassification on genotype/phenotype associations.

METHODS

Ten records of patients with Crohn's disease (CD) were independently evaluated by 19 observers using a standardized inflammatory bowel disease documentation system, which included the Vienna Classification. Interobserver agreement (IOA) was calculated as a percentage of the observers' agreement with a predetermined reference observer and by Cohen's kappa. Randomized reclassifications were then computed with 10,000 simulation runs using the IOA results and published NOD2/CARD15 gene status. A chi-square independence test was calculated for each simulation run.

RESULTS

IOA for location and behavior was 70% (K = 0.57) and 95% (K = 0.91), respectively. IOA for location subgroups ranged from 48% to 88% and for behavior from 91% to 97%. By including the results of histopathology into the evaluation of location, the overall IOA increased significantly, to 80% (P = 0.019). Assuming a true genotype/phenotype association, the proportion of studies with nonsignificant findings (P > 0.05) because of the observed misclassification of location ranged from 13.3% to 63.8% and of behavior from 0.2% to 22.2%, depending on a study sample size of 500 or 150 patients respectively.

CONCLUSIONS

We concluded that there is appreciable interobserver disagreement on the location of CD according to the original Vienna Classification that may obscure true genotype/phenotype associations. Definitions of disease parameters have to be validated before being used as the bases for classifications.