DWI-MR and PET-CT Functional Imaging for Boost Tumor Volume Delineation in Neoadjuvant Rectal Cancer Treatment

BACKGROUND/AIM T2 weighted magnetic resonance (MR) imaging is the gold standard for locally advanced rectal cancer (LARC) staging. The potential benefit of functional imaging, as diffusion-weighted MR (DWI) and positron emission tomography-computed tomography (PET-CT), could be considered for treatment intensification strategies. Dose intensification resulted in better pathological complete response (pCR) rates. This study evaluated the inter-observer agreement between two radiation oncologists, and the difference in gross tumor volume (GTV) delineation in simulation-CT, T2-MR, DWI-MR, and PET-CT in patients with LARC. PATIENTS AND METHODS Two radiation oncologists prospectively delineated GTVs of 24 patients on simul-CT (CT$_{GTV}$), T2-weighted MR (T2$_{GTV}$), echo planar b1000 DWI (DWI$_{GTV}$) and PET-CT (PET$_{GTV}$). Observers' agreement was assessed using Dice index. Kruskal-Wallis test assessed differences between methods. RESULTS Mean CT$_{GTV}$, T2$_{GTV}$, DWI$_{GTV}$, and PET$_{GTV}$ were 41.3±26.9 cc, 25.9±15.2 cc, 21±14.8 cc, and 37.7±27.7 cc for the first observer, and 42.2±27.9 cc, 27.6±16.9 cc, 19.9±14.9cc, and 34.8±24.3 cc for the second observer, respectively. Mean Dice index was 0.85 for CT$_{GTV}$, 0.84 for T2$_{GTV}$, 0.82 for DWI$_{GTV}$, and 0.89 for PET$_{GTV}$, representative of almost perfect agreement. Kruskal-Wallis test showed a statistically significant difference between methods (p=0.009). Dunn test showed there were differences between DWI$_{GTV}$ vs. PET$_{GTV}$ (p=0.040) and DWI$_{GTV}$ vs. CT$_{GTV}$ (p=0.008). CONCLUSION DWI resulted in smaller volume delineation compared to CT, T2-MR, and PET-CT functional images. Almost perfect agreements were reported for each imaging modality between two observers. DWI-MR seems to remain the optimal strategy for boost volume delineation for dose escalation in patients with LARC

European union leadership in biofuels regulation: Europe as a normative power?

The rapid emergence of the European Union (EU) as a leader in global environmental politics has led many scholars to argue in favour of the EU being a ‘normative power’ in international relations. This paper critically examines the EU's biofuels policy and evaluates whether its attempts to lead by example and shape international practice in this field could support such arguments. Europe's biofuel policies are evaluated through a sustainable development lens, so as to determine the extent to which it has embraced a holistic approach to sustainability. While not dismissing that the identity of the EU is indeed an explanatory factor and that normative intentions may well be regarded as a motivating force, this study argues that an interest-based perspective on international environmental regulation offers a supplementary view of how an actor's preferences for an international regime are shaped. By erecting barriers aimed at shielding its own inefficient domestic biofuels production the EU is in essence placing trade competitiveness and economic growth above environmental protection, thus permitting sustainability concerns to be addressed only in part

Photosynthetic process and activities of enzymes involved in the phenylpropanoid pathway in resistant ans sensitive genotypes of Lycopersicon esculentum L. exposed to ozone

Two differential pathogen-sensitive genotypes of Lycopersicon esculentum plants were treated with a single pulse of ozone (150 nL L1 for 3 h) and the photosynthetic process and activity of some enzymes of phenylpropanoid metabolism were studied. The sensitive to pathogen variety, Cuor di Bue, showed visible symptoms of injury following the ozone fumigation while the pathogen resistant line 93.1033/1 did not. CO2 fixation ability was compromised in both genotypes but in line 93.1033/1 a complete recovery in photoassimilation of CO2 was observed the day after the end of the fumigation when in Cuor di Bue a further decrease was recorded. No differences between the two tomato lines were found in chlorophyll fluorescence parameters. Shikimate dehydrogenase (SKDH; E.C. 1.1.1.25), L-phenylalanine ammonia-lyase (PAL; E.C. 4.3.1.5) and cinnamyl alcohol dehydrogenase (CAD; E.C. 1.1.1.195) activities in particular were assayed 24 h after the end of the O3 treatment in order to obtain additional information on the biochemical parameters involved in the ozone response. PAL and SKDH increased significantly only in line 93.1033/1 while CAD diminished in both the genotypes. In the resistant line a mechanism attributable to that induced by fungal pathogens was presumable. On the contrary, no clear behavior could be followed for Cuor di Bue

Prevalence and Functional Significance of Antipituitary Antibodies in Patients with Autoimmune and Non-Autoimmune Thyroid Diseases

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Post-operative residual disease and number of cycles of neoadjuvant chemotherapy in advanced epithelial ovarian carcinoma

BackgroundThe optimal number of neoadjuvant chemotherapy cycles in patients with advanced ovarian cancer is still disputed. ObjectiveTo evaluate the impact of the number of neoadjuvant chemotherapy cycles and role of optimal cytoreduction on the prognosis of patients with advanced ovarian cancer. MethodsClinical and pathological details were examined. Patients were evaluated combining the number of cycles of neoadjuvant chemotherapy-namely, 'interval debulking surgery' after up to four neoadjuvant chemotherapy cycles, and 'delayed debulking surgery' after more than four cycles of therapy. ResultsA total of 286 patients were included in the study. Complete cytoreduction with no residual peritoneal disease (CC0) was achieved in 74 (74%) patients with interval debulking surgery and 124 (66.7%) patients with delayed interval debulking. Of those with residual disease, there were 26/88 (29.5%) patients in the interval debulking surgery group and 62/88 (70.5%) patients in the delayed debulking surgery group. Comparison of patients with delayed debulking-CC0 and interval debulking-CC0 showed no difference in progression-free survival (p=0.3) or overall survival (p=0.4), while significantly worse outcomes were observed in patients with interval debulking-CC1 (p=0.02 and p=0.04, respectively). Specifically, patients with interval debulking-CC1 had an approximately 67% increased risk of disease progression (p=0.04; HR=2.01 (95% CI 1.04 to 4.18)) and a 69% higher risk of death than patients with delayed debulking-CC0 (p=0.03; HR=2.34 (95% CI 1.11 to 4.67)). ConclusionIncreasing the number of neoadjuvant chemotherapy cycles does not worsen patient outcomes if complete resection is achieved. Nevertheless, additional prospective trials are necessary to establish the optimum number of neoadjuvant chemotherapy cycles