Observation of Two New Excited Ξ_{b}^{0} States Decaying to Λ_{b}^{0}K^{-}π^{+}

Two narrow resonant states are observed in the Λ_{b}^{0}K^{-}π^{+} mass spectrum using a data sample of proton-proton collisions at a center-of-mass energy of 13 TeV, collected by the LHCb experiment and corresponding to an integrated luminosity of 6  fb^{-1}. The minimal quark content of the Λ_{b}^{0}K^{-}π^{+} system indicates that these are excited Ξ_{b}^{0} baryons. The masses of the Ξ_{b}(6327)^{0} and Ξ_{b}(6333)^{0} states are m[Ξ_{b}(6327)^{0}]=6327.28_{-0.21}^{+0.23}±0.12±0.24 and m[Ξ_{b}(6333)^{0}]=6332.69_{-0.18}^{+0.17}±0.03±0.22  MeV, respectively, with a mass splitting of Δm=5.41_{-0.27}^{+0.26}±0.12  MeV, where the uncertainties are statistical, systematic, and due to the Λ_{b}^{0} mass measurement. The measured natural widths of these states are consistent with zero, with upper limits of Γ[Ξ_{b}(6327)^{0}]<2.20(2.56) and Γ[Ξ_{b}(6333)^{0}]<1.60(1.92)  MeV at a 90% (95%) credibility level. The significance of the two-peak hypothesis is larger than nine (five) Gaussian standard deviations compared to the no-peak (one-peak) hypothesis. The masses, widths, and resonant structure of the new states are in good agreement with the expectations for a doublet of 1D Ξ_{b}^{0} resonances.

First Application of Mass Measurements with the Rare-RI Ring Reveals the Solar r-Process Abundance Trend at A=122 and A=123

The Rare-RI Ring (R3) is a recently commissioned cyclotronlike storage ring mass spectrometer dedicated to mass measurements of exotic nuclei far from stability at Radioactive Isotope Beam Factory (RIBF) in RIKEN. The first application of mass measurement using the R3 mass spectrometer at RIBF is reported. Rare isotopes produced at RIBF-^{127}Sn, ^{126}In, ^{125}Cd, ^{124}Ag, ^{123}Pd-were injected in R3. Masses of ^{126}In, ^{125}Cd, and ^{123}Pd were measured whereby the mass uncertainty of ^{123}Pd was improved. This is the first reported measurement with a new storage ring mass spectrometry technique realized at a heavy-ion cyclotron and employing individual injection of the preidentified rare nuclei. The latter is essential for the future mass measurements of the rarest isotopes produced at RIBF. The impact of the new ^{123}Pd result on the solar r-process abundances in a neutron star merger event is investigated by performing reaction network calculations of 20 trajectories with varying electron fraction Y_{e}. It is found that the neutron capture cross section on ^{123}Pd increases by a factor of 2.2 and β-delayed neutron emission probability, P_{1  n}, of ^{123}Rh increases by 14%. The neutron capture cross section on ^{122}Pd decreases by a factor of 2.6 leading to pileup of material at A=122, thus reproducing the trend of the solar r-process abundances. The trend of the two-neutron separation energies (S_{2n}) was investigated for the Pd isotopic chain. The new mass measurement with improved uncertainty excludes large changes of the S_{2n} value at N=77. Such large increase of the S_{2n} values before N=82 was proposed as an alternative to the quenching of the N=82 shell gap to reproduce r-process abundances in the mass region of A=112-124.

Detection rate of endoscopic ultrasound and computed tomography in diagnosing pancreatic neuroendocrine neoplasms including small lesions: a multicenter study

BACKGROUND/PURPOSE

The detection ability and role of different imaging modalities to detect pancreatic neuroendocrine neoplasms (PNENs) including small lesions is unclear. This study aimed to compare the ability of endoscopic ultrasound (EUS) and computed tomography (CT) to detect PNENs.

METHODS

Data of patients who underwent EUS and contrast-enhanced CT and were diagnosed with PNENs were analyzed. The detection rates of pancreatic lesions with EUS and CT based on tumor size and influencing factors were investigated.

RESULTS

For 256 PNEN lesions, the detection rate of EUS was better than that of CT (94.5% vs. 86.3%; p < 0.001). EUS was significantly superior to CT for PNENs ≤ 5 mm (58.3% vs 16.7%; p = 0.006) and 5-10 mm (97.7% vs 79.5%; p = 0.008). There was no significant difference in the detection rate between EUS and CT for PNENs > 10 mm (98.4% vs 96.4%; p = 0.375). Size (≤ 5 mm) and insulinoma were independent factors associated with poor EUS and CT detection rates.

CONCLUSIONS

EUS exhibited better detection ability than CT, with an excellent detection rate for PNENs > 5 mm, except for insulinomas. CT could detect PNENs > 10 mm, which are amenable to treatment.

Direct Measurement of the Nickel Spectrum in Cosmic Rays in the Energy Range from 8.8 GeV/n to 240 GeV/n with CALET on the International Space Station

The relative abundance of cosmic ray nickel nuclei with respect to iron is by far larger than for all other transiron elements; therefore it provides a favorable opportunity for a low background measurement of its spectrum. Since nickel, as well as iron, is one of the most stable nuclei, the nickel energy spectrum and its relative abundance with respect to iron provide important information to estimate the abundances at the cosmic ray source and to model the Galactic propagation of heavy nuclei. However, only a few direct measurements of cosmic-ray nickel at energy larger than ∼3  GeV/n are available at present in the literature, and they are affected by strong limitations in both energy reach and statistics. In this Letter, we present a measurement of the differential energy spectrum of nickel in the energy range from 8.8  to 240  GeV/n, carried out with unprecedented precision by the Calorimetric Electron Telescope (CALET) in operation on the International Space Station since 2015. The CALET instrument can identify individual nuclear species via a measurement of their electric charge with a dynamic range extending far beyond iron (up to atomic number Z=40). The particle's energy is measured by a homogeneous calorimeter (1.2 proton interaction lengths, 27 radiation lengths) preceded by a thin imaging section (3 radiation lengths) providing tracking and energy sampling. This Letter follows our previous measurement of the iron spectrum [1O. Adriani et al. (CALET Collaboration), Phys. Rev. Lett. 126, 241101 (2021).PRLTAO0031-900710.1103/PhysRevLett.126.241101], and it extends our investigation on the energy dependence of the spectral index of heavy elements. It reports the analysis of nickel data collected from November 2015 to May 2021 and a detailed assessment of the systematic uncertainties. In the region from 20 to 240  GeV/n our present data are compatible within the errors with a single power law with spectral index -2.51±0.07.

Impact of Gemcitabine Plus S1 Neoadjuvant Chemotherapy on Borderline Resectable Perihilar Cholangiocarcinoma

BACKGROUND

Surgical resection is the only curative strategy for perihilar cholangiocarcinoma (PHC), but recurrence rates are high even after purported curative resection. This study aimed to evaluate the efficacy and safety of gemcitabine/S-1 (GS) combination chemotherapy in the neoadjuvant setting.

METHODS

In an open-label, single-arm, phase 2 study, neoadjuvant chemotherapy (NAC) with GS, repeated every 21 days, was administered for three cycles to patients with histologic or cytologically confirmed borderline resectable (BR) PHC who were eligible for inclusion in the study. In this study, BR PHC was defined as positive for lymph node metastasis and for cancerous vascular invasion or Bismuth type 4 on preoperative imaging. The primary end point consisted of the 3- and 5-year survival rates. The secondary end points were feasibility, resection rate, and pathologic effect.

RESULTS

The study enrolled 60 patients between January 2011 and December 2016. With respect to toxicity, the major adverse effect was neutropenia, which reached grade 3 or 4 in 53.3% of cases. The overall disease control rate was 91.3%. The median survival time for the entire cohort was 30.3 months. For all the patients, the estimated 3-year survival rate was 44.1%, and the 5-year survival rate was 30.0%. Resection with curative intent was performed for 43 (71%) of the 60 patients. For 81% of the resected patients, R0 resection was performed, and Clavien-Dindo grade 3 complications or a higher morbidity rate was seen in 41% of the patients. The median survival time was 50.1 months for the resected and 14.8 months for the unresected patients. For the resected patients, the estimated 3-year survival rate was 55.8%, and the estimated 5-year survival rate was 36.4%.

CONCLUSIONS

Gemcitabine/S-1 combination NAC has promising efficacy and good tolerability for patients with BR PHC.

Study of Z Bosons Produced in Association with Charm in the Forward Region

Events containing a Z boson and a charm jet are studied for the first time in the forward region of proton-proton collisions. The data sample used corresponds to an integrated luminosity of 6  fb^{-1} collected at a center-of-mass energy of 13 TeV with the LHCb detector. In events with a Z boson and a jet, the fraction of charm jets is determined in intervals of Z-boson rapidity in the range 2.0<y(Z)<4.5. A sizable enhancement is observed in the forwardmost y(Z) interval, which could be indicative of a valencelike intrinsic-charm component in the proton wave function.

Evidence for a New Structure in the J/ψp and J/ψp[over ¯] Systems in B_{s}^{0}→J/ψpp[over ¯] Decays

An amplitude analysis of flavor-untagged B_{s}^{0}→J/ψpp[over ¯] decays is performed using a sample of 797±31 decays reconstructed with the LHCb detector. The data, collected in proton-proton collisions between 2011 and 2018, correspond to an integrated luminosity of 9  fb^{-1}. Evidence for a new structure in the J/ψp and J/ψp[over ¯] systems with a mass of 4337_{-4}^{+7} _{-2}^{+2}  MeV and a width of 29_{-12}^{+26} _{-14}^{+14}  MeV is found, where the first uncertainty is statistical and the second systematic, with a significance in the range of 3.1 to 3.7σ, depending on the assigned J^{P} hypothesis.

Adjuvant S-1 versus observation in curatively resected biliary tract cancer: A phase III trial (JCOG1202: ASCOT)

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Background: Capecitabine is usually used for patients with curatively resected biliary tract cancer (BTC) in EU and US, but no clear survival benefit has been shown in phase III trials. S-1, an oral fluoropyrimidine derivative, has shown promising efficacy, with a mild toxicity profile, in patients with advanced BTC. The aim of this trial was to confirm whether adjuvant S-1 therapy might improve the overall survival (OS) in patients with curatively resected BTC. Methods: This open-label, multicenter, randomized phase III trial was conducted in 38 Japanese hospitals. Eligible patients were aged 20 to 80 years old, had undergone R0/R1 resection for histologically confirmed adeno(squamous) carcinoma of the extrahepatic bile duct, gallbladder or ampulla of Vater (T2-4, N0, M0 or T1-4, N1, M0) or the intrahepatic bile duct (T1-4, N0-1, M0) (7th UICC classification), and had an ECOG performance status (PS) of 0 or 1.The calculated sample size was 440 to detect hazard ratio for OS of 0.74 with one-sided alpha of 5% and a power of 80%. Patients in surgery-alone arm received no further anti-cancer treatment, while those in adjuvant S-1 arm received 4 cycles of oral S-1 chemotherapy at the dose of 40 mg/m2 twice daily for 4 weeks, followed by 2 weeks of rest. Primary endpoint was OS, and secondary endpoints were relapse-free survival (RFS), incidence of adverse events, and proportion of treatment completion. Results: A total of 440 patients (surgery-alone, n = 222; adjuvant S-1, n = 218) were enrolled from September 2013 to June 2018. The data cutoff date was June 23, 2021, and the median follow-up duration was 45.4 months. Of all randomized patients, OS was significantly longer with adjuvant S-1 than surgery-alone (hazard ratio [HR] 0.694, 95%CI, 0.514-0.935; one-sided p = 0.008; the 3-year OS, 67.6% [surgery-alone; 95%CI, 61.0-73.3%] and 77.1% [adjuvant S-1; 95%CI, 70.9-82.1%]). Adjuvant S-1 was also better for RFS (HR 0.797 [95%CI, 0.613-1.035], 3-year RFS, 50.9% [surgery-alone; 95%CI, 44.1-57.2%] and 62.4% [adjuvant S-1; 95%CI, 55.6-68.4%]). All preplanned subgroup analyses (PS, age, cancer type, cancer stage, R factor, and serum CA19-9) revealed favorable OS and RFS for adjuvant S-1 arm. The main grade 3-4 adverse events in adjuvant S-1 arm were biliary tract infection (7.2%), diarrhea (2.9%), appetite loss (2.9%), fatigue (2.9%), and the treatment was well-tolerated. Conclusions: Adjuvant S-1 therapy led to significantly longer survival than surgery alone and becomes the standard of care for resected BTC. Clinical trial information: UMIN000011688.

Feasibility of adjuvant S-1 chemotherapy after major hepatectomy for biliary tract cancers: An exploratory subset analysis of JCOG1202

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Background: JCOG1202 (UMIN000011688) is a randomized phase III trial conducted in patients (pts) with biliary tract cancers (BTCs) that showed the superiority of adjuvant S-1, in terms of the overall survival (OS). Previous reports have suggested that major hepatectomy (MH) may affect the dose intensity as well as frequency of adverse events (AEs) and reduce the treatment efficacy of chemotherapy, due to impaired liver function and drug metabolism. Therefore, we investigated whether MH might affect the feasibility of adjuvant S-1 chemotherapy. Methods: Among the 440 pts enrolled in the JCOG1202 study, 207 pts who received adjuvant S-1 were included in this analysis. We compared the rate of treatment completion, the frequency of AEs, and the dose intensity of adjuvant S-1 after MH versus non-major hepatectomy (NMH). MH was defined as right hemi-hepatectomy, right trisectionectomy, left trisectionectomy, and central bi-sectionectomy, with or without pancreatoduodenectomy. Results: Of the 207 pts, 42 pts had undergone MH and 165 pts had undergone NMH. The primary cancers in the MH group were mainly intrahepatic cholangiocarcinoma and hilar cholangiocarcinoma. The pretreatment characteristics of the pts were as follows: performance status 0 (MH vs. NMH: 81.0% vs. 89.1%), biliary reconstruction (performed: 81.0% vs. 82.4%), time from hepatectomy to initiation of adjuvant S-1 therapy (median: 60 vs. 57 days), platelet count (17.7 vs. 23.4 x 104/μL), and serum albumin (3.5 vs. 3.8 g/dL). The treatment completion proportion was lower in the MH group as compared to the NMH group (59.5% vs. 75.8%; treatment completion ratio, 0.786 (95% CI, 0.603-1.023), p = 0.0733), and the median dose intensity was lower in the MH group than in the NMH group (90% vs. 100%, p = 0.0358). The proportion of pts who discontinued adjuvant S-1 due to occurrence of AEs in the MH group vs. the NMH group was 23.8% vs. 10.3%. The major reasons for treatment discontinuation were biliary infection, nausea/vomiting, and diarrhea; these AEs were mainly observed in the first cycle; the frequency of grade 3-4 biliary infection during adjuvant S-1 therapy was 19.0% in the MH group versus 4.2% in the NMH group. Conclusions: In regard to adjuvant S-1 therapy for pts with resected BTC, the treatment completion proportion and dose intensity were lower in the MH group as compared to the NMH group. Caution should be exercised against the development of biliary infections during postoperative adjuvant S-1 therapy after MH in BTC pts.

New insights into the genetic contribution of ALDH2 rs671 in pancreatic carcinogenesis: evaluation by mediation analysis

A functional variant on ALDH2 rs671 (G>A) confers a protective effect against alcohol‐induced carcinogenesis through an indirect pathway mediated by decreased alcohol consumption. Conversely, this variant also contributes to the accumulation of carcinogenic agents, resulting in a direct carcinogenic effect. This study aimed to separately quantify these two opposing effects of the rs671 A allele on pancreatic cancer risk and explore the impact of the rs671 A allele and alcohol consumption on pancreatic carcinogenesis. We included 426 cases and 1456 age‐ and sex‐matched controls. Odds ratio (OR) and 95% confidence interval (CI) for alcohol consumption were estimated using a conditional logistic regression model. By defining rs671 A allele and alcohol consumption as exposure and mediator, respectively, we used mediation analysis to decompose the total‐effect OR of the rs671 A allele into direct‐ and indirect‐effect ORs. Alcohol consumption (10 g/d) was associated with pancreatic cancer risk (OR, 1.05; 95% CI, 1.01‐1.10), but tests for interaction between the rs671 A allele and alcohol consumption were nonsignificant, indicating that the effect of alcohol consumption did not vary by genotype. Mediation analysis showed that the nonsignificant total effect (OR, 1.15; 95% CI, 0.92‐1.44) can be decomposed into the carcinogenic direct (OR, 1.34; 95% CI, 1.04‐1.72) and protective indirect effect (OR, 0.86; 95% CI, 0.77‐0.95). This study supports the association between alcohol consumption and pancreatic cancer risk and indicates the potential contribution of the rs671 A allele to pancreatic carcinogenesis through impaired metabolism of known or unknown ALDH2 substrates.

Transition from spin glass to paramagnetism in the magnetic properties of PrAu2Si2

It is unexpected that a spin-glass (SG) transition, which generally occurs only in systems with some form of disorder, was observed in the ThCr₂Si₂-type compound PrAu₂Si₂at a temperature of ∼3 K. This puzzling phenomenon was later explained based on a novel dynamic frustration model that does not involve static disorder. We present the results of re-verification of the reported SG behaviors by measuring the physical properties of three polycrystalline PrAu₂Si₂samples annealed under different conditions. Indeed, in the sample annealed at 827 °C for one week, a SG transition does occur at a temperature ofT_f∼ 2.8 K as that reported previously in the literature. However, it is newly found that the SG effect is actually more pronounced in the as-cast sample, and almost completely disappears in the well-annealed (at 850 °C for four weeks) sample. The annealing effect observed in PrAu₂Si₂, that is, SG to paramagnetism transition is discussed by comparing with earlier results reported on the same system and other isomorphic compounds.

PCR-based quantitative detection of intraperitoneal free cancer cells for predicting locoregional recurrence after rectal cancer resection

INTRODUCTION

Locoregional recurrence after curative resection remains an important issue in the treatment of colorectal cancer (CRC). The aim of the present study was to investigate the clinical significance of quantitative detection of intraperitoneal free cancer cells by a PCR-based method for predicting locoregional recurrence after CRC resection.

METHOD

A total of 114 patients with CRC were enrolled between March 2017 and December 2018, and 95 patients with Stage I-III CRC were analyzed. Peritoneal lavage fluid was collected before and after tumour resection and subjected to cytology and quantitative reverse transcription-PCR (qRT-PCR) with carcinoembryonic antigen (CEA) as a genetic marker.

RESULTS

2.1% of patients had positive cytology after resection, whereas 9.5% had positive CEA qRT-PCR (PCR+) after resection. Eight of nine PCR+ patients after resection had tumours in the rectum. Fifteen (15.8%) patients developed recurrence during the follow-up period, including three with locoregional recurrence. One of 86 (1.2%) PCR- patients and 2 of 9 (22.2%) PCR+ patients after resection developed locoregional recurrence. Overall and in rectal cancer patients, the 3-year cumulative risk of locoregional recurrence was 25.0% and 28.6% for PCR+ patients, which is significantly higher than PCR- patients (1.3% and 0%, P < 0.001 and P = 0.001, respectively).

CONCLUSION

Intraperitoneal free cancer cells can serve as a sensitive predictor of locoregional recurrence after rectal cancer resection. qRT-PCR for CEA can be a suitable method for detecting intraperitoneal free cancer cells in peritoneal lavage fluid.

Robot-assisted enucleation of a giant submucosal tumor in the upper esophagus

Few reports have demonstrated robotic surgery for large tumors in the upper esophagus. We report a case of a 52-year-old woman with a giant submucosal tumor in the upper esophagus successfully enucleated using robotic surgery. She presented with odynophagia and dysphagia, with subsequent evaluation revealing a submucosal mass measuring approximately 10 cm in diameter in the upper esophagus. The mass was compressing the trachea and enlarged over 3 years. Endoscopic ultrasound fine needle aspiration of the tumor was non-diagnostic. Robot-assisted esophageal submucosal tumor enucleation was performed for diagnosis and treatment. Flexible forceps control allowed for a multi-directional approach to dissect the tumor and stable forceps handling was critical in this delicate procedure. Subsequent pathological review revealed a well-differentiated esophageal liposarcoma. While surgical margins were not entirely negative, the local recurrence rate of the tumor is low. At the patient's request, we decided to observe the patient without additional resection.

Influence of Perceived Ageism on Older Adults: Focus on Attitudes toward Young People and Life Satisfaction

The world’s population is aging, and intergenerational conflicts between older adults and young people are becoming more serious. This study focused on ageism as a cause of intergenerational conflicts and older adults’ diminished mental health status. We conducted an online survey of older Japanese participants (n = 1.096). Our results indicated that older adults who perceived more ageism directed toward them (1) had more negative attitudes toward young people and (2) had lower life satisfaction, which persisted even after controlling for variables such as old age identity and depressive tendencies. Accordingly, we suggest that ageism may reinforce intergenerational conflicts between older adults and young people and compromise older adults’ mental health status. The findings of this study can aid gerontological and psychological research aimed at reducing ageism.

OUP accepted manuscript

There are two techniques for a spleen-preserving distal pancreatectomy (SPDP): SPDP with splenic vessel preservation, and SPDP with splenic vessel resection. In some cases, although the splenic artery (SpA) can be preserved, the splenic vein (SpV) must be resected. We report the short- and long-term outcomes of three patients who underwent a new technique of laparoscopic SPDP with SpA preservation and SpV resection (SPDP-VRes). A grade B pancreatic fistula, which occurred in two patients, was successfully treated with drainage tube management. In all cases, the omental branches of the left gastroepiploic vein functioned as a drainage vein, and there was no splenomegaly, thrombocytopenia, or varix formation during the follow-up period (19 months to 5 years). Patients undergoing laparoscopic SPDP-VRes had no severe complications during the follow-up period; preserving the left omental branch is a key to this procedure. Laparoscopic SPDP-VRes might be a useful treatment option for patients undergoing SPDP.

Hepatectomy Followed by mFOLFOX6 Versus Hepatectomy Alone for Liver-Only Metastatic Colorectal Cancer (JCOG0603): A Phase II or III Randomized Controlled Trial

PURPOSE

Adjuvant chemotherapy after hepatectomy is controversial in liver-only metastatic colorectal cancer (CRC). We conducted a randomized controlled trial to examine if adjuvant modified infusional fluorouracil, leucovorin, and oxaliplatin (mFOLFOX6) is superior to hepatectomy alone for liver-only metastasis from CRC.

PATIENTS AND METHODS

In this phase II or III trial (JCOG0603), patients age 20-75 years with confirmed CRC and an unlimited number of liver metastatic lesions were randomly assigned to hepatectomy alone or 12 courses of adjuvant mFOLFOX6 after hepatectomy. The primary end point of phase III was disease-free survival (DFS) in intention-to-treat analysis.

RESULTS

Between March 2007 and January 2019, 300 patients were randomly assigned to hepatectomy alone (149 patients) or hepatectomy followed by chemotherapy (151 patients). At the third interim analysis of phase III with median follow-up of 53.6 months, the trial was terminated early according to the protocol because DFS was significantly longer in patients treated with hepatectomy followed by chemotherapy. With median follow-up of 59.2 months, the updated 5-year DFS was 38.7% (95% CI, 30.4 to 46.8) for hepatectomy alone compared with 49.8% (95% CI, 41.0 to 58.0) for chemotherapy (hazard ratio, 0.67; 95% CI, 0.50 to 0.92; one-sided P = .006). However, the updated 5-year overall survival (OS) was 83.1% (95% CI, 74.9 to 88.9) with hepatectomy alone and 71.2% (95% CI, 61.7 to 78.8) with hepatectomy followed by chemotherapy. In the chemotherapy arm, the most common grade 3 or higher severe adverse event was neutropenia (50% of patients), followed by sensory neuropathy (10%) and allergic reaction (4%). One patient died of unknown cause after three courses of mFOLFOX6 administration.

CONCLUSION

DFS did not correlate with OS for liver-only metastatic CRC. Adjuvant chemotherapy with mFOLFOX6 improves DFS among patients treated with hepatectomy for CRC liver metastasis. It remains unclear whether chemotherapy improves OS.

Effects of Gas Adsorption Properties of an Au-Loaded Porous In2O3 Sensor on NO2-Sensing Properties

Gas adsorption properties of semiconductor-type gas sensors using porous (pr-) In₂O₃ powders loaded with and without 0.5 wt % Au (Au/pr-In₂O₃ and pr-In₂O₃ sensors, respectively) at 100 °C were examined by using diffuse reflectance infrared Fourier transform spectroscopy, and the effect of the Au loading onto pr-In₂O₃ on the NO₂-sensing properties were discussed in this study. We found the following: the resistance of the Au/pr-In₂O₃ sensor in dry air is lower than that of the pr-In₂O₃ sensor; the DRIFT spectra of both the sensors show a broad positive band between 1600 and 1000 cm^-1 in dry air (reference: in dry N₂ at 100 °C), which mainly originates from oxygen adsorbates and/or lattice oxygen, and that this band is much larger for the Au/pr-In₂O₃ sensor than for the pr-In₂O₃ sensor; the Au loading also increases the adsorption amount of H₂O and the reactivity of NO₂ on the pr-In₂O₃ surface; and the NO₂ response of the Au/pr-In₂O₃ sensor in dry air is marginally higher than that of the pr-In₂O₃ sensor in the examined concentration range of NO₂ (0.6-5 ppm) in dry air. The obtained results strongly support the enhancement of the NO₂ adsorption onto the pr-In₂O₃ surface by Au loading, which contributed to the improvement of the NO₂-sensing properties.

Continuous suture is a risk factor for benign hepaticojejunostomy stenosis after pancreatoduodenectomy in patients with a non-dilated bile duct

BACKGROUND

It is unclear whether hepaticojejunostomy with a continuous suture is suitable for patients with a non-dilated bile duct.

METHODS

Medical records of patients who underwent pancreatoduodenectomy between 2003 and 2013 were retrospectively reviewed, focusing on the incidence of benign anastomotic stenosis and its relationship with suture method (continuous vs interrupted) and common hepatic duct size.

RESULTS

Among 336 patients, 172 had a non-dilated (<8 mm) duct, and the remaining 164 had a dilated duct. Benign stenosis occurred in 12.2% (21/172) in the former, but in only 0.6% (1/164) in the latter (p < 0.001; median follow-up period, 43.5 months). Thus, further analysis was conducted in the 172 patients with a non-dilated duct, among whom 116 received a continuous suture and 56 received an interrupted suture. The cumulative incidence of benign anastomotic stenosis was significantly higher in patients who received a continuous suture vs those who received an interrupted suture (15.6% vs 1.8%, respectively, at 3 years; p = 0.006). Multivariable analysis identified continuous suture, male gender, and cholangitis (within 3 months after surgery) as independent risk factors for benign stenosis.

CONCLUSIONS

In this observational study, the use of a continuous suture was associated with benign anastomotic stricture in patients with a non-dilated hepatic duct.

Predictors of thermal increase in magnetic resonance-guided focused ultrasound treatment for essential tremor: histogram analysis of skull density ratio values for 1024 elements

OBJECTIVE

Sufficient thermal increase capable of generating thermocoagulation is indispensable for an effective clinical outcome in patients undergoing magnetic resonance-guided focused ultrasound (MRgFUS). The skull density ratio (SDR) is one of the most dominant predictors of thermal increase prior to treatment. However, users currently rely only on the average SDR value (SDRmean) as a screening criterion, although some patients with low SDRmean values can achieve sufficient thermal increase. The present study aimed to examine the numerical distribution of SDR values across 1024 elements to identify more precise predictors of thermal increase during MRgFUS.

METHODS

The authors retrospectively analyzed the correlations between the skull parameters and the maximum temperature achieved during unilateral ventral intermediate nucleus thalamotomy with MRgFUS in a cohort of 55 patients. In addition, the numerical distribution of SDR values was quantified across 1024 elements by using the skewness, kurtosis, entropy, and uniformity of the SDR histogram. Next, the authors evaluated the correlation between the aforementioned indices and a peak temperature > 55°C by using univariate and multivariate logistic regression analyses. Receiver operating characteristic curve analysis was performed to compare the predictive ability of the indices. The diagnostic performance of significant factors was also assessed.

RESULTS

The SDR skewness (SDRskewness) was identified as a significant predictor of thermal increase in the univariate and multivariate logistic regression analyses (p < 0.001, p = 0.013). Moreover, the receiver operating characteristic curve analysis indicated that the SDRskewness exhibited a better predictive ability than the SDRmean, with area under the curve values of 0.847 and 0.784, respectively.

CONCLUSIONS

The SDRskewness is a more accurate predictor of thermal increase than the conventional SDRmean. The authors suggest setting the SDRskewness cutoff value to 0.68. SDRskewness may allow for the inclusion of treatable patients with essential tremor who would have been screened out based on the SDRmean exclusion criterion.

Significance of Antimicrobial Prophylaxis for the Prevention of Early-Onset Pneumonia After Radical Esophageal Cancer Resection: A Retrospective Analysis of 356 Patients Undergoing Thoracoscopic Esophagectomy

BACKGROUND

Postoperative pneumonia is a common complication after esophagectomy and is associated with a high mortality rate. Although many randomized, controlled trials have been conducted on the prevention of postoperative pneumonia, little attention has been paid to the efficacy of antimicrobial prophylaxis. The purpose of this study was to investigate the impact of antimicrobial prophylaxis on the prevention of postoperative pneumonia.

METHODS

Data of patients with esophageal cancer who underwent thoracoscopic esophagectomy between 2016 and 2020 were collected. Early-period patients received cefazolin (CEZ) per protocol as antimicrobial prophylaxis (n = 250), and later-period patients received ampicillin/sulbactam (ABPC/SBT) (n = 106) because of the unavailability of CEZ in Japan. The incidence of pneumonia was compared between treatments in this quasi-experimental setting. Pneumonia detected by routine computed tomography (CT) on postoperative Days 5-6 was defined as early-onset pneumonia, and pneumonia that developed later was defined as late-onset pneumonia.

RESULTS

The incidence of early-onset pneumonia was significantly lower (3.8% vs. 13.6%, P = 0.006), and the median length of postoperative hospital stay was significantly shorter (17 vs. 20 days, P < 0.001) in the ABPC/SBT group than in the CEZ group. The incidence of late-onset pneumonia was similar between groups (9.4% vs. 10.0%, P = 0.870). The incidence of Clostridioides difficile infections and the incidence of multidrug-resistant organisms were similar between groups. Multivariate analyses consistently showed the superiority of ABPC/SBT to CEZ in preventing early-onset pneumonia (odds ratio: 0.20, P = 0.006).

CONCLUSIONS

ABPC/SBT after esophagectomy was better at preventing early-onset pneumonia compared with CEZ and was feasible regarding the development of antimicrobial resistance.

Should the Supraclavicular Lymph Nodes be Considered Regional Lymph Nodes in Cervical Esophageal Cancer?

BACKGROUND

The importance of supraclavicular lymph node (SCLN) metastases in esophageal cancer (EC) remains unknown. Few studies have reported on the prognostic impact of SCLN metastases on patients with cervical EC (CEC). This study aimed to investigate whether SCLNs should be considered regional lymph nodes and be dissected in patients with CEC.

METHODS

This retrospective study enrolled 835 consecutive patients who underwent radical esophagectomy. Of these patients, 67 underwent radical surgery for CEC. These 67 patients were divided into three groups based on the presence of lymph node metastases with or without metastatic SCLNs or the absence of lymph node metastases.

RESULTS

Of the 67 patients, 23 (34.3%) did not have metastatic lymph nodes (pN-negative group), 27 (40.3%) had metastatic lymph nodes except for metastatic SCLNs (pN-positive group without metastatic SCLN), and 17 (25.4%) had metastatic lymph nodes including metastatic SCLNs (pN-positive group with metastatic SCLNs). The 5-year overall survival rate was 58.4% for the pN-negative group, 46.2% for the pN-positive group without metastatic SCLNs, and 7.8% for the pN-positive group with metastatic SCLNs. The pN-positive group with metastatic SCLNs tended to show residual tumor cells and complications after surgery. The presence of metastatic SCLNs was a significantly poor prognostic factor (p = 0.004). The efficacy index was lowest for the lymph nodes in the supraclavicular region.

CONCLUSIONS

The prognosis of the CEC patients with metastatic SCLNs was dismal. Although the cervical esophagus is located adjacent to the SCLNs, the SCLNs may be considered extra-regional lymph nodes in patients with CEC.

A novel laparoscopic assisted mediastinal dissection with gastric tube inversion technique for gastric tube cancer reconstructed through a retrosternal route

A median sternotomy is often performed in patients with gastric tube cancer reconstructed through the retrosternal route; however, this procedure is invasive and has the risk of severe infectious complications. To overcome these problems, we created a novel method to perform the reconstructed gastric tube resection using a gastric tube inversion technique combined with a laparoscopic mediastinal approach. After the duodenum was divided, the oral side of the cut end was sutured with silken threads for traction. The gastric tube was dissected from the caudal side under a laparoscopic mediastinal approach, whereas the cervical esophagus was taped. After the adhesion between the middle side of the posterior sternum and the reconstructed gastric tube was dissected to the cervix, the gastric tube was inverted by guiding and pulling the thread toward the cervical side. Sharp dissection was facilitated between the inverted gastric tube and the surrounding organs under moderate traction and a favorable surgical view. We have performed this procedure and evaluated the short-term outcomes in six cases. The laparoscopic mediastinal approach was completed without a median sternotomy in all six cases. Restorable intraoperative lung injury was observed in one case and no major vessel injuries were observed. The postoperative course was satisfactory with a 29.5-day median length of hospital stay (range, 16-60 days). The gastric tube inversion technique combined with the laparoscopic mediastinal approach for patients with retrosternal-reconstructed gastric tube cancer was shown to be safe and less invasive and should be considered in resection of the reconstructed gastric tube.

MYB mediates downregulation of the colorectal cancer metastasis suppressor heterogeneous nuclear ribonucleoprotein L-like during epithelial-mesenchymal transition

Heterogeneous nuclear ribonucleoprotein L-like (HNRNPLL), a suppressor of colorectal cancer (CRC) metastasis, is transcriptionally downregulated when CRC cells undergo epithelial-mesenchymal transition (EMT). Here we show that decrease of MYB mediates the downregulation of HNRNPLL during EMT. The promoter activity was attributed to a region from -273 to -10 base pairs upstream of the transcription start site identified by 5'-RACE analysis, and the region contained potential binding sites for MYB and SP1. Luciferase reporter gene assays and knockdown or knockout experiments for genes encoding the MYB family proteins, MYB, MYBL1, and MYBL2, revealed that MYB was responsible for approximately half of the promoter activity. On the other hand, treatment with mithramycin A, an inhibitor for SP1 and SP3, suppressed the promoter activity and their additive contribution was confirmed by knockout experiments. The expression level of MYB was reduced on EMT while that of SP1 and SP3 was unchanged, suggesting that the downregulation of HNRNPLL during EMT was mediated by the decrease of MYB expression while SP1 and SP3 determine the basal transcription level of HNRNPLL. Histopathological analysis confirmed the accumulation of MYB-downregulated cancer cells at the invasion front of clinical CRC tissues. These results provide an insight into the molecular mechanism underlying CRC progression.

A pilot study to investigate the histomorphometric changes of murine maxillary bone around the site of mini-screw insertion in regenerated bone induced by anabolic reagents

OBJECTIVE

The objective of this study was to investigate the histomorphometric changes around the site of mini-screw insertion in the regenerated bone which was induced by an anabolic-injection method using both anabolic peptide and bone morphogenetic protein 2 (BMP-2).

METHODS

Twenty-seven eight-week-old C57BL/6J male mice were used. Some mice received submucosal co-injections of anabolic peptide and BMP-2 just in front of the maxillary first molar. Screw insertion was then performed 4 weeks after injection. All mice underwent a weekly in vivo micro-focal X-ray computed tomography (µCT) analysis before being sacrificed at week 8. The bone formation activity was evaluated using fluorescent labelling in the undecalcified sections. The analyses, including screw insertion, were performed in the frontal plane, in front of the site of screw insertion.

RESULTS

Reconstructed µCT images revealed that the co-injection of anabolic reagents could lead to a gradual increase in the bone mineral density (BMD) of the injection-induced thickened bone by week 8. Both radiological and histomorphometric analyses indicated that screw insertion did not have any deleterious effects on either the BMD or the bone formation activity of the induced bone. Furthermore, the injection of anabolic reagents also led to an increase in the BMD of the underlying maxillary bone at the injection site.

CONCLUSION

Our histomorphometric analyses suggest that performing such anabolic injection to thicken bone could stimulate bone formation in the basal bone as well as in the induced bone. Similar augmentation of bone formation could be obtained even after subsequent screw insertion at the site of the induced bone.

Identification of Blood-Based Biomarkers for the Prediction of the Response to Neoadjuvant Chemoradiation in Rectal Cancer

Simple Summary

Although pathologic complete response (pCR) to neoadjuvant chemoradiation (nCRT) in locally advanced rectal cancer (LARC) is associated with better outcomes, a subset of tumors exhibit resistance to nCRT. Therefore, there is a need of biomarkers to predict the nCRT response and increment efforts for personalized therapeutic options. To this end, we analyzed pretreatment plasma proteome of a mouse model of rectal cancer treated with concurrent chemoradiation, resulting in identification and validation of plasma VEGFR3 as a potential predicting biomarker. In addition, plasma levels of EGFR and COX2, previously validated tissue-based predicting biomarkers, were significantly higher in non-pCR than pCR LARC patients, indicating that EGFR and COX2 can also serve as blood-based biomarkers. The performance of the biomarker panel combining VEGFR3, EGFR, and COX2 were significantly improved compared to that of each marker alone, providing a rationale for further integration and refinement of the biomarker panel and validation in the larger sample sets.

Abstract

The current standard of care for patients with locally advanced rectal cancer (LARC) is neoadjuvant chemoradiation (nCRT) followed by total mesorectal excision surgery. However, the response to nCRT varies among patients and only about 20% of LARC patients achieve a pathologic complete response (pCR) at the time of surgery. Therefore, there is an unmet need for biomarkers that could predict the response to nCRT at an early time point, allowing for the selection of LARC patients who would or would not benefit from nCRT. To identify blood-based biomarkers for prediction of nCRT response, we performed in-depth quantitative proteomic analysis of pretreatment plasma from mice bearing rectal tumors treated with concurrent chemoradiation, resulting in the quantification of 567 proteins. Among the plasma proteins that increased in mice with residual rectal tumor after chemoradiation compared to mice that achieved regression, we selected three proteins (Vascular endothelial growth factor receptor 3 [VEGFR3], Insulin like growth factor binding protein 4 [IGFBP4], and Cathepsin B [CTSB]) for validation in human plasma samples. In addition, we explored whether four tissue protein biomarkers previously shown to predict response to nCRT (Epidermal growth factor receptor [EGFR], Ki-67, E-cadherin, and Prostaglandin G/H synthase 2 [COX2]) also act as potential blood biomarkers. Using immunoassays for these seven biomarker candidates as well as Carcinoembryonic antigen [CEA] levels on plasma collected before nCRT from 34 patients with LARC (6 pCR and 28 non-pCR), we observed that levels of VEGFR3 (p = 0.0451, AUC = 0.720), EGFR (p = 0.0128, AUC = 0.679), and COX2 (p = 0.0397, AUC = 0.679) were significantly increased in the plasma of non-pCR LARC patients compared to those of pCR LARC patients. The performance of the logistic regression model combining VEGFR3, EGFR, and COX2 was significantly improved compared with the performance of each biomarker, yielding an AUC of 0.869 (sensitivity 43% at 95% specificity). Levels of VEGFR3 and EGFR were significantly decreased 5 to 7 months after tumor resection in plasma from 18 surgically resected rectal cancer patients, suggesting that VEGFR3 and EGFR may emanate from tumors. These findings suggest that circulating VEGFR3 can contribute to the prediction of the nCRT response in LARC patients together with circulating EGFR and COX2.

Measurement of the Iron Spectrum in Cosmic Rays from 10 GeV/n to 2.0 TeV/n with the Calorimetric Electron Telescope on the International Space Station

The Calorimetric Electron Telescope (CALET), in operation on the International Space Station since 2015, collected a large sample of cosmic-ray iron over a wide energy interval. In this Letter a measurement of the iron spectrum is presented in the range of kinetic energy per nucleon from 10  GeV/n to 2.0  TeV/n allowing the inclusion of iron in the list of elements studied with unprecedented precision by space-borne instruments. The measurement is based on observations carried out from January 2016 to May 2020. The CALET instrument can identify individual nuclear species via a measurement of their electric charge with a dynamic range extending far beyond iron (up to atomic number Z=40). The energy is measured by a homogeneous calorimeter with a total equivalent thickness of 1.2 proton interaction lengths preceded by a thin (3 radiation lengths) imaging section providing tracking and energy sampling. The analysis of the data and the detailed assessment of systematic uncertainties are described and results are compared with the findings of previous experiments. The observed differential spectrum is consistent within the errors with previous experiments. In the region from 50  GeV/n to 2  TeV/n our present data are compatible with a single power law with spectral index -2.60±0.03.

Clinical benefits of a swallowing intervention for esophageal cancer patients after esophagectomy

Dysphagia after esophagectomy is the main cause of a prolonged postoperative stay. The present study investigated the effects of a swallowing intervention led by a speech-language-hearing therapist (SLHT) on postoperative dysphagia. We enrolled 276 consecutive esophageal cancer patients who underwent esophagectomy and cervical esophagogastric anastomosis between July 2015 and December 2018; 109 received standard care (control group) and 167 were treated by a swallowing intervention (intervention group). In the intervention group, swallowing function screening and rehabilitation based on each patient's dysfunction were led by SLHT. The start of oral intake, length of oral intake rehabilitation, and length of the postoperative stay were compared in the two groups. The patient's subgroups in the 276 patients were examined to clarify the more effectiveness of the intervention. The start of oral intake was significantly earlier in the intervention group (POD: 11 vs. 8 days; P = 0.009). In the subgroup analysis, the length of the postoperative stay was also significantly shortened by the swallowing intervention in patients without complications (POD: 18 vs. 14 days; P = 0.001) and with recurrent laryngeal nerve paralysis (RLNP) (POD: 30 vs. 21.5 days; P = 0.003). A multivariate regression analysis identified the swallowing intervention as a significant independent factor for the earlier start of oral intake and a shorter postoperative stay in patients without complications and with RLNP. Our proposed swallowing intervention is beneficial for the earlier start of oral intake and discharge after esophagectomy, particularly in patients without complications and with RLNP. This program may contribute to enhanced recovery after surgery.

The immunological impact of preoperative chemoradiotherapy on the tumor microenvironment of pancreatic cancer

Several therapeutic regimens, including neoadjuvant chemoradiation therapy (NACRT), have been reported to serve as anticancer immune effectors. However, there remain insufficient data regarding the immune response after NACRT in pancreatic ductal adenocarcinoma (PDAC) patients. Data from 40 PDAC patients that underwent surgical resection after NACRT (NACRT group) and 30 PDAC patients that underwent upfront surgery (US group) were analyzed to examine alterations in immune cell counts/distribution using a multiplexed fluorescent immunohistochemistry system. All immune cells were more abundant in the cancer stroma than in the cancer cell nest regardless of preoperative therapy. Although the stromal counts of CD4+ T cells, CD20+ B cells, and Foxp3+ T cells in the NACRT group were drastically decreased in comparison with those of the US group, counts of these cell types in the cancer cell nest were not significantly different between the two groups. In contrast, CD204+ macrophage counts in the cancer stroma were similar between the NACRT and US groups, while those in the cancer cell nests were significantly reduced in the NACRT group. Following multivariate analysis, only a high CD204+ macrophage count in the cancer cell nest remained an independent predictor of shorter relapse-free survival (odds ratio = 2.37; P = .033). NACRT for PDAC decreased overall immune cell counts, but these changes were heterogeneous within the cancer cell nests and cancer stroma. The CD204+ macrophage count in the cancer cell nest is an independent predictor of early disease recurrence in PDAC patients after NACRT.

Possibilities for and limits of upfront surgical strategy with lateral pelvic node dissection for low rectal cancer

BACKGROUND

Metastatic lateral pelvic nodes represent an important cause of pelvic recurrence in low rectal cancer patients even after preoperative chemoradiotherapy. This study aimed to evaluate the prognostic benefit of an upfront lateral pelvic nodes dissection strategy.

METHODS

A total of 175 consecutive patients with stage II/III low rectal adenocarcinoma who underwent mesorectal excision with lateral pelvic nodes dissection between 1998 and 2013 were identified. Regional lateral pelvic nodes were categorized as LD2 nodes (internal iliac, hypogastric and obturator) and LD3 nodes (external iliac, common iliac, lateral sacral, presacral and sacral promontory) according to the current Japanese Society for Cancer of the Colon and Rectum classification.

RESULTS

Five-year cumulative risks of local recurrence and recurrence-free survival were 4.8% and 78.1% for stage II patients, and 11.8% and 61.7% for stage III patients, respectively. Among stage III patients, no differences were observed in cumulative risks of local recurrence (5 years: 9.3% vs 14.7%, P= 0.463) and recurrence-free survival (5 years: 65.1 vs 61.2%, P = 0.890) between lateral pelvic nodes (-) and LD2 (+) patients. In multivariate analyses, metastatic lateral pelvic nodes had no impact on cumulative risks of local recurrence (hazard ratioadj: 1.389; 95% confidence interval: 0.409-4.716) and recurrence-free survival (hazard ratioadj: 0.884; 95% confidence interval: 0.425-1.837).

CONCLUSIONS

Metastatic lateral pelvic nodes had no impact on cumulative risks of local recurrence and recurrence-free survival based on an upfront lateral pelvic nodes strategy. Lateral pelvic nodes can improve recurrence and survival outcomes in locally advanced low rectal cancer patients with metastatic lateral pelvic nodes.

Survival benefit of surgery for very elderly patients with pancreatic cancer: what extent of pancreatectomy is acceptable?

The purpose of this study is to clarify the survival benefit and acceptable extent of surgery for very elderly patients with pancreatic cancer. Patients (n=55) ≥80 years with resectable pancreatic cancer were studied. 29 underwent pancreatectomy, 16 underwent chemotherapy, and 10 received best supportive care. Uni and multivariate analysis were performed to explore predictive factors for overall survival (OS) with surgery and chemotherapy (n=45). Postoperative survival of PD (pancreatoduodenectomy) and DP (distal pancreatectomy) and of PD-PVR (PD with portal vein resection) and PD were compared. OS was equivalent with surgery and chemotherapy (median survival time [MST]; 685 vs. 626 days, respectively; p=0.057); 6 patients surivived ≥3 years after surgery. Pancreatectomy was not a prognostic factor. Survival was significantly worse with PD-PVR than with PD, but equivalent with PD and DP. Within 2 years after PD-PVR, 8 patients have died. Surgery was not a positive prognostic factor for very elderly patients with pancreatic cancer, but was the sole chance for survival ≥3 years. Indication for PD-PVR for very elderly patients should be determined more cautiously compared with that for non-elderly patients.

Probing the Symmetry Energy with the Spectral Pion Ratio

Many neutron star properties, such as the proton fraction, reflect the symmetry energy contributions to the equation of state that dominate when neutron and proton densities differ strongly. To constrain these contributions at suprasaturation densities, we measure the spectra of charged pions produced by colliding rare isotope tin (Sn) beams with isotopically enriched Sn targets. Using ratios of the charged pion spectra measured at high transverse momenta, we deduce the slope of the symmetry energy to be 42<L<117  MeV. This value is slightly lower but consistent with the L values deduced from a recent measurement of the neutron skin thickness of ^{208}Pb.

Quasifree Neutron Knockout Reaction Reveals a Small s-Orbital Component in the Borromean Nucleus ^{17}B

A kinematically complete quasifree (p,pn) experiment in inverse kinematics was performed to study the structure of the Borromean nucleus ^{17}B, which had long been considered to have a neutron halo. By analyzing the momentum distributions and exclusive cross sections, we obtained the spectroscopic factors for 1s_{1/2} and 0d_{5/2} orbitals, and a surprisingly small percentage of 9(2)% was determined for 1s_{1/2}. Our finding of such a small 1s_{1/2} component and the halo features reported in prior experiments can be explained by the deformed relativistic Hartree-Bogoliubov theory in continuum, revealing a definite but not dominant neutron halo in ^{17}B. The present work gives the smallest s- or p-orbital component among known nuclei exhibiting halo features and implies that the dominant occupation of s or p orbitals is not a prerequisite for the occurrence of a neutron halo.

Bronchial fistula and esophageal stricture following endoscopic trans-gastric drainage for a mediastinal pancreatic pseudocyst

A 43-year-old man with alcoholic cirrhosis and chronic alcoholic pancreatitis was referred for evaluation of chest pain and an enlarging pleural effusion. Computed tomography revealed a bilateral pleural effusion and longitudinal multilocular pancreatic pseudocysts extending to the posterior mediastinum along the esophagus. He was diagnosed with a mediastinal pancreatic pseudocyst rupturing into the pleural cavity and was initially treated with endoscopic ultrasound-guided trans-gastric drainage. After 4 months of stable disease, dysphagia and a severe cough developed due to an esophageal stricture and main bronchial fistula. Considering the inadequate drainage, the trans-gastric drainage stent was surgically exchanged for a percutaneous external drain and the bronchial fistula was repaired using an intercostal muscle flap. After improvement of the mediastinal abscess and the symptoms, he was discharged on post-operative day 72. Two years post-operatively, he is in good health with no recurrence. We herein report a rare case of a bronchial fistula and esophageal stricture after endoscopic trans-gastric drainage of a mediastinal pancreatic pseudocyst. Endoscopic trans-gastric drainage is an effective treatment for mediastinal pancreatic pseudocysts, but it is important to provide appropriate alternative treatment depending on the course of treatment.

Risk factors for peristomal skin disorders associated with temporary ileostomy construction

PURPOSE

Skin disorders are the most common stoma-related complications after temporary diverting loop ileostomy with proctectomy. The aim of the present study was to investigate risk factors for skin disorders associated with temporary ileostomy construction.

METHODS

A total of 185 consecutive patients who underwent curative proctectomy with temporary diverting loop ileostomy for rectal malignancies at a single comprehensive cancer center between 2013 and 2018 were collected and analyzed.

RESULTS

The most frequent stoma-related complications were skin disorders (n = 62, 33.5%), followed by mucocutaneous separation (n = 38, 20.5%) and high-output stoma (n = 34, 18.4%). Patients with skin disorders had a higher median body mass index (BMI; 22.4 vs. 21.3 kg/m², P = 0.002) and lower stoma height (16 vs. 20 mm, P < 0.001) than those without skin disorders. According to a multivariable logistic regression analysis, independent predictors of skin disorders included overweight (median BMI ≥ 25 kg/m² [odds ratio = 3.6, 95% confidence interval: 1.5-8.6], P = 0.004) and lower stomal height (median stoma height < 20 mm [odds ratio = 3.2, 95% confidence interval: 1.6-6.3], P < 0.001).

CONCLUSION

Overweight and lower stoma height are correlated with the presence of skin disorders. Construction of a well-elevated stoma can reduce skin disorders associated with temporary ileostomy construction.

Aggressive and frequent resection of recurrences in retroperitoneal sarcoma contributes to long-term survival

PURPOSE

Retroperitoneal sarcoma (RPS) is a rare tumor with a poor prognosis and is often undetected until it is significantly enlarged. While surgical resection remains the primary treatment, there is little research on its benefits, especially that concerning the reoperation of recurrent disease. This study investigated the impact of surgical procedures, especially reoperation of recurrent RPS, on prognosis.

METHODS

This retrospective study included 51 patients who underwent radical resection surgery (R0 status) for primary or recurrent RPS without distant metastasis. Patient outcomes and prognosis were defined in terms of the clinicopathologic factors and surgical techniques performed.

RESULTS

In all cases, the 5-year disease-free survival (DFS) rate was 28.2%, 5-year overall survival rate was 89.9%, and 5-year no residual liposarcoma rate was 54.3% after operation and re-reoperation. There was a statistically significant difference between the 5-year DFS rate and 5-year no residual liposarcoma rate due to frequent re-reoperation (p = 0.011). On univariate analysis of primary and recurrent lesions, the histological type and the number of organs involved were identified as statistically significant prognostic factors. Patients with well-differentiated liposarcomas had a statistically better prognosis than those with other cancer types (primary RPS, p = 0.028; recurrence, p = 0.024).

CONCLUSIONS

Aggressive and frequent resection of recurrent RPS with combined resection of adjacent organs contributes to long-term survival. The establishment of a surgical strategy for RPS will require a prospective study.

Tolerability of Nab-Paclitaxel Plus Gemcitabine as Adjuvant Setting in Japanese Patients With Resected Pancreatic Cancer: Phase I Study

OBJECTIVE

The combination of gemcitabine plus nab-paclitaxel (GnP) has not been studied in Japanese patients with resectable pancreatic cancer (PC). This study aimed to assess the tolerability of adjuvant GnP in Japanese patients with resected PC.

METHODS

This was a Phase I, open-label, multicenter, single-arm study of patients with resected PC in Japan. Patients received 125 mg/m2 of nab-paclitaxel and 1000 mg/m2 of gemcitabine on days 1, 8, and 15 of a 28-day cycle for a total of 6 cycles. The primary end point was tolerability, defined as the absence of specific grade 3 or higher treatment-related adverse events by the end of cycle 2. Secondary end points included safety, disease-free survival, and overall survival.

RESULTS

Forty-one patients were enrolled between June 2016 and February 2017 (median age, 68 years; 51% male; stage II, 95%). Gemcitabine plus nab-paclitaxel met the tolerability criteria in 39 of the 40 patients included in the tolerability analysis set (97.5%). The most common treatment-related adverse events were leukopenia, neutropenia, alopecia, and peripheral sensory neuropathy. After a follow-up of 30.1 months, median disease-free survival was 17.0 months and median overall survival was not reached.

CONCLUSIONS

These results show that adjuvant GnP is tolerable in Japanese patients with resected PC.Clinical Trial Registration No.: JapicCTI-163179.

Limited Clinical Significance of Splenectomy and Splenic Hilar Lymph Node Dissection for Type 4 Gastric Cancer

Purpose

Type 4 gastric cancer (GC) has a very poor prognosis even after curative resection, and the survival benefit of splenectomy for splenic hilar lymph node (LN; #10) dissection in type 4 GC remains equivocal. This study aimed to clarify the clinical significance of splenectomy for #10 dissection in patients with type 4 GC.

Materials and Methods

The data of a total of 56 patients with type 4 GC who underwent total gastrectomy with splenectomy were retrospectively analyzed. Postoperative morbidity, state of LN metastasis, survival outcomes, and therapeutic value index (TVI) of each LN station were evaluated. TVI was calculated by multiplying the incidence of LN metastasis at each nodal station and the 5-year overall survival (OS) of patients who had metastasis to each node.

Results

Overall, the postoperative morbidity rate was 28.6%, and the incidence of #10 metastasis in the patients was 28.6%. The 5-year OS rate for all patients was 29.9%, and most patients developed peritoneal recurrence. Moreover, the 5-year OS rates with and without #10 metastasis were 6.7% and 39.1% (median survival time, 20.4 vs. 46.0 months; P=0.006). The TVI of #10 was as low as 1.92.

Conclusions

The clinical significance of splenectomy in the dissection of #10 for type 4 GC is limited and splenectomy for splenic hilar dissection alone should be omitted.

Direct Measurement of the Cosmic-Ray Carbon and Oxygen Spectra from 10 GeV/n to 2.2 TeV/n with the Calorimetric Electron Telescope on the International Space Station

In this paper, we present the measurement of the energy spectra of carbon and oxygen in cosmic rays based on observations with the Calorimetric Electron Telescope on the International Space Station from October 2015 to October 2019. Analysis, including the detailed assessment of systematic uncertainties, and results are reported. The energy spectra are measured in kinetic energy per nucleon from 10  GeV/n to 2.2  TeV/n with an all-calorimetric instrument with a total thickness corresponding to 1.3 nuclear interaction length. The observed carbon and oxygen fluxes show a spectral index change of ∼0.15 around 200  GeV/n established with a significance >3σ. They have the same energy dependence with a constant C/O flux ratio 0.911±0.006 above 25  GeV/n. The spectral hardening is consistent with that measured by AMS-02, but the absolute normalization of the flux is about 27% lower, though in agreement with observations from previous experiments including the PAMELA spectrometer and the calorimetric balloon-borne experiment CREAM.

Surface Localization of the Dineutron in ^{11}Li

The formation of a dineutron in the ^{11}Li nucleus is found to be localized to the surface region. The experiment measured the intrinsic momentum of the struck neutron in ^{11}Li via the (p,pn) knockout reaction at 246  MeV/nucleon. The correlation angle between the two neutrons is, for the first time, measured as a function of the intrinsic neutron momentum. A comparison with reaction calculations reveals the localization of the dineutron at r∼3.6  fm. The results also support the density dependence of dineutron formation as deduced from Hartree-Fock-Bogoliubov calculations for nuclear matter.