Assessing the use of magnetic resonance imaging virtopsy as an alternative to autopsy: a systematic review and meta-analysis

Background The post mortem examination or autopsy is a trusted method of identifying the cause of death. Patients and their families may oppose an autopsy for a variety of reasons, including fear of mutilation or owing to religious and personal beliefs. Imaging alternatives to autopsy have been explored, which may provide a viable alternative. Objective To explore the possibility of using MRI virtopsy to establish the cause of death as an alternative to the traditional post mortem examination or autopsy. Methods Systematic review was carried out of all studies, without language restriction, identified from Medline, Cochrane (1960-2016) and Embase (1991-2016) up to December 2016. Further searches were performed using the bibliographies of articles and abstracts. All studies reporting the diagnosis of the cause of death by both MRI virtopsy and traditional autopsy were included. Results Five studies with 107 patients, contributed to a summative quantitative outcome in adults. The combined sensitivity of MRI virtopsy was 0.82 (95% CI 0.56 to 0.94) with a diagnostic odds ratio (DOR) of 11.1 (95% CI 2.2 to 57.0). There was no significant heterogeneity between studies (Q=1.96, df=4, p=0.75, I-2=0). Eight studies, with 953 patients contributed to a summative quantitative outcome in children. The combined sensitivity of MRI virtopsy was 0.73 (95% CI 0.59 to 0.84) with a DOR of 6.44 (95% CI 1.36 to 30.51). There was significant heterogeneity between studies (Q=34.95, df=7, p<0.01, I-2=80). Conclusion MRI virtopsy may offer a viable alternative to traditional autopsy. By using MRI virtopsy, a potential cost reduction of at least 33% is feasible, and therefore ought to be considered in eligible patients

PET/MR in oncology:an introduction with focus on MR and future perspectives for hybrid imaging

After more than 20 years of research, a fully integrated PET/MR scanner was launched in 2010 enabling simultaneous acquisition of PET and MR imaging. Currently, no clinical indication for combined PET/MR has been established, however the expectations are high. In this paper we will discuss some of the challenges inherent in this new technology, but focus on potential applications for simultaneous PET/MR in the field of oncology. Methods and tracers for use with the PET technology will be familiar to most readers of this journal; thus this paper aims to provide a short and basic introduction to a number of different MRI techniques, such as DWI-MR (diffusion weighted imaging MR), DCE-MR (dynamic contrast enhanced MR), MRS (MR spectroscopy) and MR for attenuation correction of PET. All MR techniques presented in this paper have shown promising results in the treatment of patients with solid tumors and could be applied together with PET increasing the amount of information about the tissues of interest. The potential clinical benefit of applying PET/MR in staging, radiotherapy planning and treatment evaluation in oncology, as well as the research perspectives for the use of PET/MR in the development of new tracers and drugs will be discussed

In vitro vascular differentiation system efficiently produces natural killer cells for cancer immunotherapies

ABSTRACTBackground Immunotherapeutic innovation is crucial for limited operability tumors. CAR T-cell therapy displayed reduced efficiency against glioblastoma (GBM), likely due to mutations underlying disease progression. Natural Killer cells (NKs) detect cancer cells despite said mutations – demonstrating increased tumor elimination potential. We developed an NK differentiation system using human pluripotent stem cells (hPSCs). Via this system, genetic modifications targeting cancer treatment challenges can be introduced during pluripotency – enabling unlimited production of modified “off-the-shelf” hPSC-NKs.Methods hPSCs were differentiated into hematopoietic progenitor cells (HPCs) and NKs using our novel organoid system. These cells were characterized using flow cytometric and bioinformatic analyses. HPC engraftment potential was assessed using NSG mice. NK cytotoxicity was validated using in vitro and in vitro K562 assays and further corroborated on lymphoma, diffuse intrinsic pontine glioma (DIPG), and GBM cell lines in vitro.Results HPCs demonstrated engraftment in peripheral blood samples, and hPSC-NKs showcased morphology and functionality akin to same donor peripheral blood NKs (PB-NKs). The hPSC-NKs also displayed potential advantages regarding checkpoint inhibitor and metabolic gene expression, and demonstrated in vitro and in vivo cytotoxicity against various cancers.Conclusions Our organoid system, designed to replicate in vivo cellular organization (including signaling gradients and shear stress conditions), offers a suitable environment for HPC and NK generation. The engraftable nature of HPCs and potent NK cytotoxicity against leukemia, lymphoma, DIPG, and GBM highlight the potential of this innovative system to serve as a valuable tool that will benefit cancer treatment and research – improving patient survival and quality of life

The sigmoid take-off: An anatomical imaging definition of the rectum validated on specimen analysis

Background A pre-operative imaging landmark to define the rectum would optimise clinical care of rectal cancer patients and research efforts to improve outcomes. The sigmoid take-off has been suggested as an imaging landmark for the rectosigmoid junction (RSJ). This study aimed to investigate whether this imaging definition of the rectum was validated by surgical specimen analysis. Methods This prospective study recruited 20 patients undergoing surgery and undertook radiological and pathological analysis of their rectal specimens. The radiological landmark of the sigmoid take-off was identified on pre-operative magnetic resonance imaging (MRI), and the distance to the anterior peritoneal reflection was measured by two readers. After surgery, the distance from the beginning of the sigmoid mesocolon to the anterior peritoneal reflection to the beginning of the sigmoid mesocolon on the specimen was measured, and compared to the distance on MRI using Pearson's Correlation Coefficient and Bland-Altman plots. Results In 17 patients, the mean distance from the anterior peritoneal reflection to the RSJ on MRI was 20.3 mm and 23.1 mm for two readers, and on pathology was 20.6 mm. The mean differences between MRI and specimen measurements were −0.31 mm (−2.83 to 2.20 mm), and 2.51 mm (95% confidence interval −0.31 to 5.33 mm) for each reader, with correlation coefficients of 0.77 and 0.81. Conclusion The sigmoid take-off has been validated on specimen analysis to be an imaging landmark that defines the termination of the rectum. This anatomical landmark can be used to classify tumours and guide treatment and research of sigmoid colon and rectal cancer

Тerminology of rectal cancer: consensus agreement of the expert working group

Unified terminology is a necessary condition for successful interdisciplinary communication within the field of oncology. The variety of anatomical, pathomorphological, and clinical terms used in rectal cancer is often accompanied by their ambiguous interpretation both in domestic and foreign scientific literature. This not only complicates the interaction between specialists, but also complicates the comparison of the results of rectal cancer treatment obtained in different medical institutions. Based on the analysis of recent domestic and international scientific and methodological literature on rectal cancer, the key terms used in the diagnosis and treatment planning of rectal cancer were selected, followed by a two-time online discussion of their interpretations by experts from the Russian Society of Radiologists and Therapeutic Radiation Oncologists, the Association of Oncologists of Russia, and the Russian Association of Therapeutic Radiation Oncologists until reaching consensus (≥80%) of experts on all items. Terms that fail to attain consensus were excluded in the final list. A list of anatomical, pathomorphological, and clinical terms used in the diagnosis, staging, and treatment planning of rectal cancer has been compiled and, based on expert consensus, their interpretation has been determined. A lexicon recommended in the description and formulation of the conclusion of diagnostic studies in patients with rectal cancer is proposed