Oesophageal cancer: assessment of tumour response to chemoradiotherapy with tridimensional CT.

PURPOSE: To investigate whether changes in tumour volume were predictive of histopathological response to neoadjuvant therapy for oesophageal cancer. MATERIALS AND METHODS: Thirty-five consecutive patients with locally advanced oesophageal cancer were treated with chemoradiotherapy and surgery in responders from July 2007 to July 2009. Tumour volume (TV) was calculated using innovative tumour volume estimation software which analysed computed tomography (CT) data. Tumour diameter and area were also evaluated. Variations in tumour measurements following neoadjuvant treatment were compared with the histopathological data. RESULTS: Median baseline tumour diameter, area and volume were 3.51 cm (range 1.67-6.61), 7.51 cm(2) (range 1.79-21.0) and 33.80 cm(3) (range 3.36-101.6), respectively. Differences in TV between the pre- and post-treatment values were significantly correlated with the pathological stage (τ = 0.357, p = 0.004) and the tumour regression grade index (τ = 0.368, p = 0.005). According to the receiver operating characteristic analysis, TV measurements following treatment had moderate predictive values for the pathological T stage (area under the curve, AUC = 0.742, sensitivity = 55.56 %, specificity = 92.86 %, p = 0.005).Comparison of pathological and radiological volume showed a good precision (Pearson rho 0.77). CONCLUSIONS: Changes in TV calculated on CT scans have a limited role in predicting pathological response to neoadjuvant treatment in oesophageal cancer patients. New imaging techniques based on metabolic imaging may provide better results.

Predicting Long-Term Endothelial Cell Loss after Preloaded Descemet Membrane Endothelial Keratoplasty in Fuchs' Endothelial Corneal Dystrophy: A Mathematical Model.

(1) Background: This study offers a biexponential model to estimate corneal endothelial cell decay (ECD) following preloaded "endothelium-in" Descemet membrane endothelial keratoplasty (DMEK) in Fuchs' endothelial corneal dystrophy (FECD) patients; (2) Methods: A total of 65 eyes undergoing DMEK alone or combined with cataract surgery were evaluated. The follow-up period was divided into an early phase (first 6 months) and a late phase (up to 36 months). Endothelial cell count (ECC) and endothelial cell loss (ECL) were analyzed; (3) Results: The half time of the ECD was 3.03 months for the early phase and 131.50 months for the late phase. The predicted time-lapse interval to reach 500 cells/mm2 was 218 months (18.17 years), while the time-lapse interval to reach 250 cells/mm2 was 349 months (29.08 years). There was no statistically significant difference between the ECL in DMEK combined with cataract extraction and DMEK alone at 24 months (p ≥ 0.20). At the late phase, long-term ECL prediction revealed a lower ECC half time in patients undergoing DMEK combined with cataract surgery (98.05 months) than DMEK alone (250.32 months); (4) Conclusions: Based on the mathematical modeling, a predicted average half-life of a DMEK graft could reach 18 years in FECD. Moreover, combining cataract extraction with DMEK could result in excessive ECL in the long term.

Practical high-dimensional quantum key distribution protocol over deployed multicore fiber.

Quantum key distribution (QKD) is a secure communication scheme for sharing symmetric cryptographic keys based on the laws of quantum physics, and is considered a key player in the realm of cyber-security. A critical challenge for QKD systems comes from the fact that the ever-increasing rates at which digital data are transmitted require more and more performing sources of quantum keys, primarily in terms of secret key generation rate. High-dimensional QKD based on path encoding has been proposed as a candidate approach to address this challenge. However, while proof-of-principle demonstrations based on lab experiments have been reported in the literature, demonstrations in realistic environments are still missing. Here we report the generation of secret keys in a 4-dimensional hybrid time-path-encoded QKD system over a 52-km deployed multicore fiber link forming by looping back two cores of a 26-km 4-core optical fiber. Our results indicate that robust high-dimensional QKD can be implemented in a realistic environment by combining standard telecom equipment with emerging multicore fiber technology.