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The aim of this study was to investigate the prognostic impact of postoperative infections in patients who underwent resection for biliary malignancy, including intrahepatic cholangiocarcinoma, perihilar cholangiocarcinoma, distal cholangiocarcinoma, gallbladder carcinoma, and carcinoma of the ampulla of Vater. This study was conducted in an 11-center retrospective cohort study. Patients with biliary tract cancer who underwent curative resection between April 2013 and March 2015 at 11 institutions in Japan were enrolled. We analyzed the prevalence of postoperative infection, infection-related factors, and prognostic factors. Of the total 290 cases, 33 were intrahepatic cholangiocarcinoma, 60 were perihilar cholangiocarcinoma, 120 were distal cholangiocarcinoma, 55 were gallbladder carcinoma, and 22 were carcinoma of the ampulla of Vater. Postoperative infectious complications, including remote infection, were observed in 146 patients (50.3%), and Clavien–Dindo ≥III in 115 patients (39.7%). Postoperative infections occurred more commonly in the patients who received pancreaticoduodenectomy and bile duct resection. Patients with infectious complications had a significantly poorer prognosis than those without (median overall survival 38 months vs 62 months, P =.046). In a diagnosis-specific analysis, although there was no correlation between infectious complications and overall survival in intrahepatic cholangiocarcinoma, perihilar cholangiocarcinoma, distal cholangiocarcinoma, and carcinoma of the ampulla of Vater, infectious complications were a significantly poor prognostic factor in gallbladder carcinoma (P =.031). Postoperative infection after surgery for biliary tract cancer commonly occurred, especially in patients who underwent pancreaticoduodenectomy and bile duct resection. Postoperative infection is relatively associated with the prognosis of patients with biliary malignancy, especially gallbladder carcinoma. [ABSTRACT FROM AUTHOR]

The prognosis for metastatic colorectal cancer patients (mCRC) with the BRAF V600E mutation is poor. BRAF V600E mutation frequency is reportedly low among Asians; however, the frequency of the BRAF V600E mutation in right-side colon cancer may not be low, even among Asians. In addition, spatial heterogeneity of BRAF V600E mutations also exists, as for RAS mutations. In this prospective observational study, we evaluated BRAF V600E mutations in cancer tissue and plasma of Japanese right-side colon cancer patients. 215 patients with right-side colon cancer were included. BRAF V600E mutations of cancer tissue and plasma were detected using droplet digital PCR. Blood plasma of patients with BRAF V600E mutations in cancer tissue or plasma was drawn at intervals throughout chemotherapy, and BRAF V600E mutations were evaluated. BRAF V600E mutations were detected in tissue samples from 35 of 215 patients (16.3%, cecum; 22.4%, ascending colon; 17.8%, and transverse colon; 9.0%). BRAF V600E mutations were detected in plasma of 10 of 215 (4.7%) patients. Eight of the ten patients had BRAF V600E mutations in their primary tumours, but two (both were Stage IV) patients did not. Sensitivity of liquid biopsy to detect BRAF V600E mutations was 10.3% (3/29) in Stage I-III patients and 83.3% (5/6) in Stage IV patients. BRAF V600E mutations are observed in right-side colon cancer at high frequency, especially in the cecum. BRAF V600E mutations can be detected in plasma and the detection rate is high in patients with advanced cancer. Spatial heterogeneity was observed using liquid biopsy. [ABSTRACT FROM AUTHOR]

Circulating tumour DNA (ctDNA) is very useful for purposes of cancer genetics; however, it has some limitations. Recently, ctDNA in body fluids, such as urine, sputum, and pleural effusion, has been investigated. The aim of this study was to evaluate the quantity of ctDNA derived from urine (trans -renal ctDNA) and the accuracy of KRAS mutation detection in relation to disease stage in colorectal cancer. Urine, plasma, and tissue samples were collected from consecutively resected colorectal cancer patients. DNA was extracted from each sample and the quantity was determined. From each DNA sample, KRAS mutations were detected using droplet digital PCR. 200 patients participated and KRAS mutations were detected in 84 patients (42.0%) from tumour tissue. The concentration of trans -renal ctDNA (trtDNA) was significantly lower than that of plasma; however, there was no significant difference between the sensitivity using ctDNA and that using trtDNA (29.8% VS 33.3%, p = 0.62). Concordance between these two tests was only 17.5%. Combination analysis (ctDNA + trtDNA) improved the sensitivity to 53.6%, and sensitivity was significantly higher than that of corresponding single assays (p = 0.003). In early cancer stages, trtDNA had greater sensitivity for detecting KRAS mutations than ctDNA (37.7% vs. 21.3%, p = 0.047). Conversely, it was less useful for advanced cancer stages (21.7% vs. 52.2%, p = 0.07). Notably, KRAS mutations were detected using ctDNA or trtDNA in 12 of 116 (10.3%) patients who had no KRAS mutations in their tissue samples. Conclusions: trtDNA and ctDNA have equal potential and combination analysis significantly improved the sensitivity. [ABSTRACT FROM AUTHOR]

High preoperative carcinoembryonic antigen (CEA) is a well-known risk factor for stage II-III colorectal cancer (CRC); however, in most cases, cancer does not recur. Conversely, postoperative CEA (post-CEA) is occasionally measured, and high post-CEA patients often develop recurrence; however, the clinical significance of post-CEA testing is unknown. The purpose of this study was to determine whether post-CEA elevation might indicate a poor prognosis for stage II-III CRC patients who underwent curative surgery. 482 patients with pathological stage II-III CRC were included. Univariate and multivariate analyses were performed to evaluate post-CEA levels. Multivariate analysis showed that elevated post-CEA (hazard ratio (HR): 3.14, P < 0.001), pathological lymph node metastasis (pN+), and pathological T4 (pT4) are associated with poor recurrence-free survival (RFS), and that elevated post-CEA (HR: 3.12; P = 0.002), pN+, pT4, age >70, and smoking are independently associated with poor overall survival. Subgroup analysis among stage III patients, in combination with the risk classification of the International Duration Evaluation of Adjuvant Chemotherapy (IDEA) study, showed that elevated post-CEA is a significant indicator of poor prognosis for RFS in both low-risk (73.8% vs. 21.2%, P < 0.001) and high-risk (49.9% vs. 25.0%, P = 0.04) groups. Post-surgical CEA elevation is independently associated with poor prognosis in stage II-III CRC. Adding post-CEA levels to the IDEA risk classification may provide a more reliable indicator of the need for individualized surveillance and adjuvant chemotherapeutic strategies. [ABSTRACT FROM AUTHOR]

Most patients with colorectal liver metastases, who undergo hepatectomy, experience recurrence. Although the prognosis is poorer for patients with early recurrence (within 6 months after hepatectomy) compared with later recurrence, no biomarker has been identified to predict early recurrence. Minimal residual disease (MRD) in patients who undergo curative surgery is the main cause of recurrence. In cancer patients, long fragment cell-free DNA is detected, and the presence of long fragments of cell-free DNA after surgery can indicate MRD. In this study, we developed a novel biomarker to predict early recurrence of colorectal liver metastases using cell-free DNA. Forty-one patients with colorectal liver metastases were enrolled. Peripheral blood samples were collected before and at 1 month after hepatectomy. Cell-free DNA was extracted from 1 ml plasma, and the long fragment/β-globin ratio, which can indicate MRD, was measured by real-time polymerase chain reaction. Three of 21 patients (14.3%) with decreases in the long cell-free DNA fragment/β-globin ratio after hepatectomy developed early recurrence compared with twelve of 20 patients (60.0%) with an increased ratio (P = 0.002). Patients with a decreased long fragment/β-globin ratio after hepatectomy had significantly longer recurrence-free survival compared with patients with an increased ratio (366 vs 102 days, P < 0.001). The cell-free DNA long fragment/β-globin ratio may serve as an effective biomarker of early recurrence in patients with colorectal liver metastases, who undergo hepatectomy. [ABSTRACT FROM AUTHOR]

We demonstrate the recent developments in the high-rate deposition technique of thin film silicon using a novel approach of plasma enhanced chemical vapor deposition. Hydrogenated amorphous silicon has been developed for thin film solar cells in the past three decades, however the severe photodegradation of the film as well as of the devices prepared at a high deposition rate has hindered the industrialization of this material. The SiH2 structure in the film has been identified as a cause of the photodegradation, and its formation mechanism has been clarified in terms of the electron temperature of the plasma, gaseous phase reactions and surface reactions. We found that the combination of a VHF plasma, proper hydrogen dilution and higher deposition temperature improves the efficiency of solar cells after photodegradation up to 8.2%, which is the highest efficiency under high deposition rate conditions. The high deposition rate technique for microcrystalline silicon has also been developed on the basis of the knowledge that a sufficiently high amount of atomic hydrogen and the reduction in the ion bombardment are the key factors for high quality microcrystalline silicon. A novel deposition technique under high-pressure depletion conditions has been developed in combination with a VHF plasma to obtain a deposition rate as high as 5 nm/s, and further development has been achieved by means of a hollow mesh so that a lot of migrating bright spot appear on the mesh to obtain a deposition rate of 5.8 nm/s with good crystallinity and a defect density as low as 2.6×1016 cm−3, which implies a device grade material. A solar cell with an efficiency of 8.1% has been prepared at a deposition rate of 1.2 nm/s. [Copyright &y& Elsevier]