Predictors of post-treatment stenosis in cervical esophageal cancer undergoing high-dose radiotherapy

AIM To evaluate toxicity and treatment outcome of highdose radiotherapy(RT) for cervical esophageal cancer(CEC).METHODS We reviewed a total of 62 consecutive patients who received definitive RT for stage Ⅰ to Ⅲ cervical esophageal cancer between 2001 and 2015. Patients who received < 45 Gy, treated for lesions below sternal notch, treated with palliative aim, treated with subsequent surgical resection, or diagnosed with synchronous hypopharyngeal cancer were excluded. Treatment failures were divided into local(occurring within the RT field), outfield-esophageal, and regional [occurring in regional lymph node(s)] failures. Factors predictive of esophageal stenosis requiring endoscopic dilation were analyzed.RESULTS Grade 1, 2, and 3 esophagitis occurred in 19(30.6%), 39(62.9%), and 4 patients(6.5%), respectively, without grade ≥ 4 toxicities. Sixteen patients(25.8%) developed post-RT stenosis, of which 7 cases(43.8%) were malignant. Four patients(6.5%) developed tracheoesophageal fistula(TEF), of which 3(75%) cases were malignant. Factors significantly correlated with post-RT stenosis were stage T3/4(P = 0.001), complete circumference involvement(P < 0.0001), stenosis at diagnosis(P = 0.024), and endoscopic complete response(P = 0.017) in univariate analysis, while complete circumference involvement was significant in multivariate analysis(P = 0.003). A higher dose(≥ 60 Gy) was not associated with occurrence of postRT stenosis or TEF. With a median follow-up of 24.3(range, 3.4-152) mo, the 2 y local control, outfield esophageal control, progression-free survival, and overall survival(OS) rates were 78.9%, 90.2%, 49.6%, and 57.3%, respectively. Factors significantly correlated with OS were complete circumference involvement(P = 0.023), stenosis at diagnosis(P < 0.0001), and occurrence of post-RT stenosis or TEF(P < 0.001) in univariate analysis, while stenosis at diagnosis(P = 0.004) and occurrence of post-RT stenosis or TEF(P = 0.023) were significant in multivariate analysis. CONCLUSION Chemoradiation for CEC was well tolerated, and a higher dose was not associated with stenosis. Patients with complete circumferential involvement require close follow-up.

Liver abscess and sepsis with Bacillus pantothenticus in an immunocompetent patient:A first case report

Bacillus species are aerobic,gram-positive,spore forming rods that are usually found in the soil,dust,streams,and other environmental sources.Except for Bacillus.anthracis(B.anthracis) ,most species display low virulence,and only rarely cause infections in hosts with weak or damaged immune systems.There are two case reports of B.cereus as a potentially serious bacterial pathogen causing a liver abscess in an immunologically competent patient.We herein report a case of liver abscess and sepsis caused by B.pantothenticus in an immunocompetent patient.Until now,no case of liver abscess due to B.pantothenticus has been reported.

Gate-versus defect-induced voltage drop and negative differential resistance in vertical graphene heterostructures

To enable the computer-aided design of vertically stacked two-dimensional(2D)van der Waals(vdW)heterostructure devices,we here introduce a non-equilibrium first-principles simulation method based on the multi-space constrained-search density functional formalism.Applying it to graphene/few-layer hBN/graphene field-effect transistors,we show that the negative differential resistance(NDR)characteristics can be produced not only from the gating-induced mismatch between two graphene Dirac cones in energy-momentum space but from the bias-dependent energetic shift of defect levels.Specifically,for a carbon atom substituted for a nitrogen atom(C_(N))within inner hBN layers,the increase of bias voltage is found to induce a self-consistent electron filling of in-gap C_(N)states,which in turn changes voltage drop profiles and produces symmetric NDR characteristics.With the CN placed on outer hBN layers,however,the pinning of C_(N)states to nearby graphene significantly modifies device characteristics,demonstrating the critical impact of atomic details for 2D vdW devices.