18 research outputs found
Quantitative assessment of the asphericity of pretherapeutic FDG uptake as an independent predictor of outcome in NSCLC
Background The aim of the present study was to evaluate the predictive value
of a novel quantitative measure for the spatial heterogeneity of FDG uptake,
the asphericity (ASP) in patients with non-small cell lung cancer (NSCLC).
Methods FDG-PET/CT had been performed in 60 patients (15 women, 45 men; median
age, 65.5 years) with newly diagnosed NSCLC prior to therapy. The FDG-PET
image of the primary tumor was segmented using the ROVER 3D segmentation tool
based on thresholding at the volume-reproducing intensity threshold after
subtraction of local background. ASP was defined as the relative deviation of
the tumor’s shape from a sphere. Univariate and multivariate Cox regression as
well as Kaplan-Meier (KM) analysis and log-rank test with respect to overall
(OAS) and progression-free survival (PFS) were performed for clinical
variables, SUVmax/mean, metabolically active tumor volume (MTV), total lesion
glycolysis (TLG), ASP and “solidity”, another measure of shape irregularity.
Results ASP, solidity and “primary surgical treatment” were significant
independent predictors of PFS in multivariate Cox regression with binarized
parameters (HR, 3.66; p < 0.001, HR, 2.11; p = 0.05 and HR, 2.09; p = 0.05),
ASP and “primary surgical treatment” of OAS (HR, 3.19; p = 0.02 and HR, 3.78;
p = 0.01, respectively). None of the other semi-quantitative PET parameters
showed significant predictive value with respect to OAS or PFS. Kaplan-Meier
analysis revealed a probability of 2-year PFS of 52% in patients with low ASP
compared to 12% in patients with high ASP (p < 0.001). Furthermore, it showed
a higher OAS rate in the case of low versus high ASP (1-year-OAS, 91% vs. 67%:
p = 0.02). Conclusions The novel parameter asphericity of pretherapeutic FDG
uptake seems to provide better prognostic value for PFS and OAS in NCSLC
compared to SUV, metabolic tumor volume, total lesion glycolysis and solidity
Comparison of different bronchial closure techniques following pneumonectomy in dogs
The comparison of the histologic healing and bronchopleural fistula (BPF) complications encountered with three different BS closure techniques (manual suture, stapler and manual suture plus tissue flab) after pneumonectomy in dogs was investigated for a one-month period. The dogs were separated into two groups: group I (GI) (n = 9) and group II (GII) (n = 9). Right and left pneumonectomies were performed on the animals in GI and GII, respectively. Each group was further divided into three subgroups according to BS closure technique: subgroup I (SGI) (n = 3), manual suture; subgroup II (SGII) (n = 3), stapler; and subgroup III (SGIII) (n = 3), manual suture plus tissue flab. The dogs were sacrificed after one month of observation, and the bronchial stumps were removed for histological examination. The complications observed during a one-month period following pneumonectomy in nine dogs (n = 9) were: BPF (n = 5), peri-operative cardiac arrest (n = 1), post-operative respiratory arrest (n = 1), post-operative cardiac failure (n = 1) and cardio-pulmonary failure (n = 1). Histological healing was classified as complete or incomplete healing. Histological healing and BPF complications in the subgroups were analyzed statistically. There was no significant difference in histological healing between SGI and SGIII (p = 1.00; p > 0.05), nor between SGII and SGIII (p = 1.00; p > 0.05). Similarly, no significant difference was observed between the subgroups in terms of BPF (p = 0.945; p > 0.05). The results of the statistical analysis indicated that manual suture, stapler or manual suture plus tissue flab could be alternative methods for BS closure following pneumonectomy in dogs