Analysis of fistula formation of T4 esophageal cancer patients treated by chemoradiotherapy.

BACKGROUND AND AIM: Fistula is one of the known complications of T4 esophageal cancer (T4-EC). The standard treatment for T4-EC is chemoradiotherapy, but detailed data about fistula resulting from chemoradiotherapy in this condition are limited. In particular, radiographic findings of T4-EC with fistula have not been reported. This study assessed the risk factors of fistula based on clinical information on patients with chemoradiotherapy for T4-EC. METHODS: We retrospectively reviewed the clinical data of 59 T4-EC patients who had squamous cell carcinoma without any fistula before receiving definitive or palliative chemoradiotherapy. RESULTS: A fistula was observed in 18 patients (31%) throughout their clinical course. The overall survival in the fistula group was significantly shorter than that in the non-fistula group (259 vs. 346 days; p = 0.0341). The axial tumor size on computed tomography (CT) was confirmed as an independent risk factor for esophageal fistula in multivariate analysis of stepwise methods [OR 1.226; 95% CI 1.109-1.411; p < 0.0001]. Twelve out of 14 patients with an axial tumor size of 50 mm or greater had developed a fistula. CONCLUSIONS: A large tumor size on the axial plane on CT is a risk factor for fistula formation.

High Axial Ratio Nanochitins for Ultrastrong and Shape-Recoverable Hydrogels and Cryogels via Ice Templating.

High yield (>85%) and low-energy deconstruction of never-dried residual marine biomass is proposed following partial deacetylation and microfluidization. This process results in chitin nanofibrils (nanochitin, NCh) of ultrahigh axial size (aspect ratios of up to 500), one of the largest for bioderived nanomaterials. The nanochitins are colloidally stable in water (ζ-potential = +95 mV) and produce highly entangled networks upon pH shift. Viscoelastic and strong hydrogels are formed by ice templating upon freezing and thawing with simultaneous cross-linking. Slow supercooling and ice nucleation at -20 °C make ice crystals grow slowly and exclude nanochitin and cross-linkers, becoming spatially confined at the interface. At a nanochitin concentration as low as 0.4 wt %, highly viscoelastic hydrogels are formed, with a storage modulus of ∼16 kPa, at least an order of magnitude larger compared to those measured for the strongest chitin-derived hydrogels reported so far. Moreover, the water absorption capacity of the hydrogels reaches a value of 466 g g-1. Lyophilization is effective in producing cryogels with a density that can be tailored in a wide range of values, from 0.89 to 10.83 mg·cm-3, and corresponding porosity, between 99.24 and 99.94%. Nitrogen adsorption results indicate reversible adsorption and desorption cycles of macroporous structures. A fast shape recovery is registered from compressive stress-strain hysteresis loops. After 80% compressive strain, the cryogels recovered fast and completely upon load release. The extreme values in these and other physical properties have not been achieved before for neither chitin nor nanocellulosic cryogels. They are explained to be the result of (a) the ultrahigh axial ratio of the fibrils and strong covalent interactions; (b) the avoidance of drying before and during processing, a subtle but critical aspect in nanomanufacturing with biobased materials; and (c) ice templating, which makes the hydrogels and cryogels suitable for advanced biobased materials.