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Background: Individualised risk prediction is crucial if targeted pre-operative risk reduction strategies are to be deployed effectively. Radiologically determined sarcopenia has been shown to predict outcomes across a range of intra-abdominal pathologies. Access to pre-operative cross-sectional imaging has resulted in a number of studies investigating the predictive value of radiologically assessed sarcopenia over recent years. This systematic review and meta-analysis aimed to determine whether radiologically determined sarcopenia predicts post-operative morbidity and mortality following abdominal surgery. Method: CENTRAL, EMBASE and MEDLINE databases were searched using terms to capture the concept of radiologically assessed sarcopenia used to predict post-operative complications in abdominal surgery. Outcomes included 30 day post-operative morbidity and mortality, 1-, 3- and 5-year overall and disease-free survival and length of stay. Data were extracted and meta-analysed using either random or fixed effects model (Revman 5.3). Results: A total of 24 studies involving 5267 patients were included in the review. The presence of sarcopenia was associated with a significant increase in major post-operative complications (RR 1.61 95% CI 1.24-4.15 p = <0.00001) and 30-day mortality (RR 2.06 95% CI 1.02-4.17 p = 0.04). In addition, sarcopenia predicted 1-, 3- and 5-year survival (RR 1.61 95% CI 1.36-1.91 p = <0.0001, RR 1.45 95% CI 1.33-1.58 p = <0.0001, RR 1.25 95% CI 1.11-1.42 p = 0.0003, respectively) and 1- and 3-year disease-free survival (RR 1.30 95% CI 1.12-1.52 p = 0.0008). Conclusion: Peri-operative cross-sectional imaging may be utilised in order to predict those at risk of complications following abdominal surgery. These findings should be interpreted in the context of retrospectively collected data and no universal sarcopenic threshold. Targeted prehabilitation strategies aiming to reverse sarcopenia may benefit patients undergoing abdominal surgery. [ABSTRACT FROM AUTHOR]

Pancreatic ductal adenocarcinoma ( PDAC) is considered a non-immunogenic tumor, and immune checkpoint inhibitor monotherapy lacks efficacy in this disease. Radiotherapy ( RT) can stimulate the immune system. Here, we show that treatment of KPC and Pan02 murine PDAC cells with RT and gemcitabine upregulated PD-L1 expression in a JAK/Stat1-dependent manner. In vitro, PD-L1 inhibition did not alter radio- and chemosensitivity. In vivo, addition of anti- PD-L1 to high (12, 5 × 3, 20 Gy) but not low (6, 5 × 2 Gy) RT doses significantly improved tumor response in KPC and Pan02 allografts. Radiosensitization after PD-L1 blockade was associated with reduced CD11b+Gr1+ myeloid cell infiltration and enhanced CD45+ CD8+ T-cell infiltration with concomitant upregulation of T-cell activation markers including CD69, CD44, and FasL, and increased CD8:Treg ratio. Depletion of CD8+ T cells abrogated radiosensitization by anti- PD-L1. Blockade of PD-L1 further augmented the effect of high RT doses (12 Gy) in preventing development of liver metastases. Exploring multiple mathematical models reveals a mechanism able to explain the observed synergy between RT and anti- PD-L1 therapy. Our findings provide a rationale for testing the use of immune checkpoint inhibitors with RT in PDAC. [ABSTRACT FROM AUTHOR]

The article presents information from a study on remote learning methods in medical education using the videoconferencing software Skype. It compares learning via traditional face-to-face instruction with learning via an audiovisual link accessed through Skype.

Emerging evidence suggests a role for radiation in eliciting anti‐tumour immunity. We aimed to investigate the role of macrophages in modulating the immune response to radiation. Irradiation to murine tumours generated from colorectal (MC38) and pancreatic (KPC) cell lines induced colony‐stimulating factor 1 (CSF‐1). Coincident with the elevation in CSF‐1, macrophages increased in tumours, peaking 5 days following irradiation. These tumour‐associated macrophages (TAMs) were skewed towards an immunosuppressive phenotype. Macrophage depletion via anti‐CSF (aCSF) reduced macrophage numbers, yet only achieved tumour growth delay when combined with radiation. The tumour growth delay from aCSF after radiation was abrogated by depletion of CD8 T cells. There was enhanced recognition of tumour cell antigens by T cells isolated from irradiated tumours, consistent with increased antigen priming. The addition of anti‐PD‐L1 (aPD‐L1) resulted in improved tumour suppression and even regression in some tumours. In summary, we show that adaptive immunity induced by radiation is limited by the recruitment of highly immunosuppressive macrophages. Macrophage depletion partly reduced immunosuppression, but additional treatment with anti‐PD‐L1 was required to achieve tumour regression. Synopsis: Increased CSF‐1 is here observed in response to tumour irradiation. Subsequent recruitment of immunosuppressive macrophages rendered the tumour microenvironment resistant to immune‐mediated tumour cell killing. Blocking CSF‐1 reduced tumour‐associated macrophages and increased sensitivity to immune checkpoint blockade. Irradiation stimulates CSF‐1 secretion by tumour cells.Immunosuppressive macrophages are increased in the tumour microenvironment after irradiation.Macrophage depletion via anti‐CSF permits CD8+ T‐cell‐mediated tumour cell killing.Macrophage depleted tumours are more sensitive to immune checkpoint blockade. Increased CSF‐1 is here observed in response to tumour irradiation. Subsequent recruitment of immunosuppressive macrophages rendered the tumour microenvironment resistant to immune‐mediated tumour cell killing. Blocking CSF‐1 reduced tumour‐associated macrophages and increased sensitivity to immune checkpoint blockade. [ABSTRACT FROM AUTHOR]

An abstract of the article "Dialogue Vodcasts: A Qualitative Assessment" by Keaton Jones et al. is presented.