Pancreatic SABR using peritumoral fiducials, triggered imaging and breath-hold

Background: We aim to present our linear accelerator-based workflow for pancreatic stereotactic ablative radiotherapy (SABR) in order to address the following issues: intrafractional organ motion management, Cone Beam CT (CBCT) image quality, residual errors with dosimetric consequences, treatment time, and clinical results.Methods: Between 2016 and 2021, 14 patients with locally advanced pancreatic cancer were treated with induction chemotherapy and SABR using volumetric modulated arc therapy (VMAT). Internal target volume (ITV) concept (5), phase-gated (4), or breath hold (5) techniques were used. Treatment was verified by CBCT before and after irradiation, while tumor motion was monitored and controlled by kV triggered imaging and beam hold using peritumoral surgical clips. Beam interruptions and treatment time were recorded. The CBCT image quality was scored and supplemented by an agreement analysis (Krippendorff’s-α) of breath-hold CBCT images to determine the position of OARs relative to the planning risk volumes (PRV). Residual errors and their dosimetry impact were also calculated. Progression free (PFS) and overall survival (OS) were assessed by the Kaplan-Meier analysis with acute and late toxicity reporting (CTCAEv4).Results: On average, beams were interrupted once (range: 0–3) per treatment session on triggered imaging. The total median treatment time was 16.7 ± 10.8 min, significantly less for breath-hold vs. phase-gated sessions (18.8 ± 6.2 vs. 26.5 ± 13.4, p < 0.001). The best image quality was achieved by breath hold CBCT. The Krippendorff’s-α test showed a strong agreement among five radiation therapists (mean K-α value: 0.8 (97.5%). The mean residual errors were <0.2 cm in each direction resulting in an average difference of <2% in dosimetry for OAR and target volume. Two patients received offline adaptation. The median OS/PFS after induction chemotherapy and SABR was 20/12 months and 15/8 months. No Gr. ≥2 acute/late RT-related toxicity was noted.Conclusion: Linear accelerator based pancreatic SABR with the combination of CBCT and triggered imaging + beam hold is feasible. Peritumoral fiducials improve utility while breath-hold CBCT provides the best image quality at a reasonable treatment time with offline adaptation possibilities. In well-selected cases, it can be an effective alternative in clinics where CBCT/MRI-guided online adaptive workflow is not available

Impact of expanded criteria variables on outcomes of kidney transplantation from donors after cardiac death

Introduction To expand the donor pool, kidney transplants are being performed using donors who were previously considered unacceptable. We applied the United Network for Organ Sharing criteria to define expanded criteria donors (ECD) within the donation after cardiac death (DCD) and donation after brain stem death (DBD) cohorts. We compared outcomes of DCD and DBD transplants with and without (standard criteria donor [SCD]) the ECD criteria. Methods This was a single-center retrospective study of all deceased donor transplants from 2004 to 2010 (n=359). Four groups were identified—DBD-SCD (n=154), DBD-ECD (n=93), DCD-SCD (n=78), and DCD-ECD (n=34). Kaplan-Meier analysis of graft and patient survival and multiple regression analysis of 1-year graft function were performed. Results One-year and two-year uncensored graft survivals were similar between DCD-ECD and DCD-SCD cohorts (1 year, 90% and 93%; 2 years, 81% and 93% respectively; log-rank test P=0.2). Median estimated glomerular filtration rate (eGFR) was lower in DCD-ECD recipients at 12 months (41 vs. 53 mL/min, P=0.003) and 24 months (33 vs. 54 mL/min, P<0.001) compared with DCD-SCD recipients. Compared with DBD-ECD recipients also at 24 months, DCD-ECD recipients showed a lower graft function (median, eGFR 33 vs. 47 mL/min; P=0.007) but similar graft survival. Expanded criteria donor status (B=−9.7, P=0.01) was associated with a lower 1-year eGFR within the DCD cohort, with donor age (B=−0.42, P=0.002) being the only significant ECD variable. Conclusion Short-term graft survival in DCD-ECD transplants was comparable to DCD-SCD and DBD-ECD transplants albeit with poorer allograft function at 2 years. Quality-of-life studies are needed to determine the true value of these transplants, particularly when performed to older recipients

L'habitant-chercheur : nouvelle figure des sciences impliquées

International audienceOur article presents a scientific collaboration between inhabitants and researchers, in which the researchers are asked to conduct research based on questions raised by the inhabitants. The research project looks at the relations of the inhabitants to nature, the environment and the landscape. The group of inhabitants and researchers focus on private gardens as spaces which preserve biodiversity and construct the landscape. This experiment confers a central role to the co-construction of methods and knowledge over time. It implies employing a special didactic two-way researcher-inhabitant approach. We introduce the figure of the «inhabitant-researcher» to express the changes in posture among the participants.Notre article présente une collaboration scientifique entre habitants et chercheurs, où les chercheurs ont été sollicités pour mettre en œuvre une recherche sur un questionnement initié par les habitants. Le projet de recherche interroge les rapports des habitants à la nature, à l’environnement et au paysage. Le collectif d’habitants et de chercheurs s’intéresse plus particulièrement aux jardins privés comme espaces de préservation de la biodiversité et de fabrication paysagère. Cette expérience accorde une place centrale à la coconstruction des méthodes et des connaissances dans la durée. Elle engage la mise en place d’une didactique particulière à double sens qui s’opère du chercheur vers l’habitant mais aussi de l’habitant vers le chercheur. Nous introduisons la figure de « l'habitant-chercheur » pour traduire les changements de posture qui se sont opérés chez les participant

Influence of delayed graft function and acute rejection on outcomes after kidney transplantation from donors after cardiac death

Background Delayed graft function (DGF) and acute rejection (AR) exert an adverse impact on graft outcomes after kidney transplantation using organs from donation after brain-stem death (DBD) donors. Here, we examine the impact of DGF and AR on graft survival in kidney transplants using organs from donation after cardiac death (DCD) donors. Methods We conducted a single-center retrospective study of DCD and DBD donor kidney transplants. We compared 1- and 4-year graft and patient survival rates, as well as death-censored graft survival (DCGS) rates, between the two groups using univariate analysis, and the impact of DGF and AR on graft function was compared using multivariate analysis. Results Eighty DCD and 206 DBD donor transplants were analyzed. Median follow-up was 4.5 years. The incidence of DGF was higher among DCD recipients (73% vs. 27%, P<0.001), and AR was higher among DBD recipients (23% vs. 9%, P<0.001). One-year and 4-year graft survival rates were similar (DCD 94% and 79% vs. DBD 90% and 82%). Among recipients with DGF, the 4-year DCGS rate was better for DCD recipients compared with DBD recipients (100% vs. 92%, P=0.04). Neither DGF nor AR affected the 1-year graft survival rate in DCD recipients, whereas in DBD recipients, the 1-year graft survival rate was worse in the presence of DGF (88% vs. 96%, P=0.04) and the 4-year DCGS rate was worse in the presence of AR (88% vs. 96%, P=0.04). Conclusion Despite the high incidence of DGF, medium-term outcomes of DCD kidney transplants are comparable to those from DBD transplants. Short-term graft survival from DCD transplants is not adversely influenced by DGF and AR, unlike in DBD transplants