Red blood cells metabolome changes upon treatment with different X-ray irradiation doses.

The upholding of red blood cells (RBC) quality and the removal of leukocytes are two essential issues in transfusion therapy. Leukodepletion provides optimum results, nonetheless there are cases where irradiation is recommended for some groups of hematological patients such as the ones with chronic graft-vs-host disease, congenital cellular immunodeficiency, and hematopoietic stem cell transplant recipients. The European guidelines suggest irradiation doses from 25 to 50 Gray (Gγ). We evaluated the effect of different prescribed doses (15 to 50 Gγ) of X-ray irradiation on fresh leukodepleted RBCs bags using a novel protocol that provides a controlled irradiation. Biochemical assays integrated with RBCs metabolome profile, assessed by nuclear magnetic resonance spectroscopy, were performed on RBC units supernatant, during 14 days storage. Metabolome analysis evidenced a direct correlation between concentration increase of three metabolites, glycine, glutamine and creatine, and irradiation dose. Higher doses (35 and 50 Gγ) effect on RBC mean corpuscular volume, hemolysis, and ammonia concentration are considerable after 7 and 14 days of storage. Our data show that irradiation with 50 Gγ should be avoided and we suggest that 35 Gγ should be the upper limit. Moreover, we suggest for leukodepleted RBCs units the irradiation with the prescribed dose of 15 Gγ, value at center of bag, and ranging between 13.35-15 Gγ, measured over the entire bag volume, may guarantee the same benefits of a 25 Gγ dose assuring, in addition, a better quality of RBCs.

LatticeOpt: An automatic tool for planning optimisation of spatially fractionated stereotactic body radiotherapy.

PURPOSE: Lattice radiotherapy (LRT) is a three dimensional (3D) implementation of spatially fractionated radiation therapy, based on regular spatial distribution of high dose spheres (vertices) inside the target. Due to tumour shape heterogeneity, finding the best lattice arrangement is not trivial. The aim of this study was to develop the LatticeOpt tool to generate the best lattice structures on clinical cases for treatment planning. METHODS: Developed in MATLAB, LatticeOpt finds the 3D-spatial configurations that maximize the number of vertices within the gross target volume (GTV). If organs at risk (OARs) are considered, it chooses the solution that minimizes the overlapping volume histograms (OVH). Otherwise, the lattice structure with the minimum Hausdorff distance between vertices and GTV boundary is chosen to avoid unpopulated regions. Different lattice structures were created for 20 patients, with (OVHopt) and without (OVHunopt) OVH minimization. Imported into TPS (Eclipse, Varian), corresponding plans were generated and evaluated in terms of OAR mean and maximum doses, GTV vertex coverage and dose gradients, as well as pre-clinical plan dosimetry. RESULTS: Plans based on an optimized lattice structure (OVHopt, OVHunopt) had similar dose distributions in terms of vertex coverage and gradient index score. OAR sparing was observed in all patients, with a 4 % and 9 % difference for mean and max dose (both p-values <0.01), respectively. The best vertices dimensions and their relative distances were patient dependent. CONCLUSIONS: LatticeOpt was able to reduce the time-consuming procedures of LRT, as well as to achieve standardized and reproducible results, useful for multicentre studies.

Reduction of EpCAM-Positive Cells from a Cell Salvage Product Is Achieved by Leucocyte Depletion Filters Alone.

Intraoperative cell salvage reduces the need for allogeneic blood transfusion in complex cancer surgery, but concerns about the possibility of it re-infusing cancer cells have hindered its application in oncology. We monitored the presence of cancer cells on patient-salvaged blood by means of flow cytometry; next, we simulated cell salvage, followed by leucodepletion and irradiation on blood contaminated with a known amount of EpCAM-expressing cancer cells, assessing also residual cancer cell proliferation as well as the quality of salvaged red blood cell concentrates (RBCs). We observed a significant reduction of EpCAM-positive cells in both cancer patients and contaminated blood, which was comparable to the negative control after leucodepletion. The washing, leucodepletion and leucodepletion plus irradiation steps of cell salvage were shown to preserve the quality of RBCs in terms of haemolysis, membrane integrity and osmotic resistance. Finally, cancer cells isolated from salvaged blood lose their ability to proliferate. Our results confirm that cell salvage does not concentrate proliferating cancer cells, and that leucodepletion allows for the reduction of residual nucleated cells, making irradiation unnecessary. Our study gathers pieces of evidence on the feasibility of this procedure in complex cancer surgery. Nevertheless, it highlights the necessity of finding a definitive consensus through prospective trials.

Good clinical practice and the use of hypofractionation radiation schedules as weapons to reduce the risk of COVID-19 infections in radiation oncology unit: A mono-institutional experience.

BACKGROUND: After coronavirus disease outbreak emerged in 2019, radiotherapy departments had to adapt quickly their health system and establish new organizations and priorities. The purpose of this work is to report our experience in dealing with COVID-19 emergency, how we have reorganized our clinical activity, changed our priorities, and stressed the use of hypofractionation in the treatment of oncological diseases. MATERIALS AND METHODS: The patients' circuit of first medical examinations and follow-up was reorganized; a more extensive use of hypofractionated schedules was applied; a daily triage of the patients and staff, use of personal protective equipment, hand washing, environment sanitization, social distancing and limitations for the patients' caregivers in the department, unless absolutely essential, were performed; patients with suspected or confirmed COVID-19 were treated at the end of the day. In addition, the total number of radiotherapy treatment courses, patients and sessions, in the period from February 15 to April 30, 2020, comparing the same time period in 2018 were retrospectively investigated. In particular, changes in hypofractionated schedules adopted for the treatment of breast and prostate cancer and palliative bone metastasis were analyzed. RESULTS: Between February 15, and April 30, 2020, an increased number of treatments was carried out: Patients treated were overall 299 compared to 284 of the same period of 2018. Stressing the use of hypofractionation, 2036 RT sessions were performed, with a mean number of fractions per course of 6.8, compared to 3566 and 12.6, respectively, in 2018. For breast cancer, the schedule in 18 fractions has been abandoned and treatment course of 13 fractions has been introduced; a 27% reduction in the use of 40.5 Gy in 15 fractions, (67 treatments in 2018-49 in 2020) was reported. An increase of 13% of stereotactic body radiation therapy for prostate cancer was showed. The use of the 20 Gy in 4 or 5 sessions for the treatment of symptomatic bone metastasis decreased of 17.5% in favor of 8 Gy-single fraction. Three patients results COVID-19 positive swab: 1 during, 2 after treatment. Only one staff member developed an asymptomatic infection. CONCLUSIONS: The careful application of triage, anti-contagion and protective measures, a more extensive use of hypofractionation allowed us to maintain an effective and continuous RT service with no delayed/deferred treatment as evidenced by the very low number of patients developing COVID-19 infection during or in the short period after radiotherapy. Our experience has shown how the reorganization of the ward priority, the identification of risk factors with the relative containment measures can guarantee the care of oncological patients, who are potentially at greater risk of contracting the infection.

The role of radiation therapy technologist in interventional radiotherapy (brachytherapy) in Italy: Italian Association of Radiotherapy and Clinical Oncology (AIRO) and Italian Association of Radiation Therapy and Medical Physics Technologists (AITRO) joint project.

PURPOSE: Interventional radiotherapy (IRT, brachytherapy and intra-operative radiotherapy) is a complex treatment approach that requires a multi-professional approach. The aim of this work was to assess the role of radiation therapy technologist (RTT) in IRT team, with a special focus on brachytherapy as well as to define more appropriate ways to improve skills and training to promote cooperation of multi-professional team. MATERIAL AND METHODS: A nationwide survey consisting of 16 questions was proposed between April and May 2020, with collaboration between the Italian Association of Radiation Therapy and Medical Physics Technologists (AITRO) and the Interventional Radiotherapy Study Group of Italian Association of Radiotherapy and Clinical Oncology (AIRO). The survey was sent through the AITRO contact list to RTTs' contacts from all Italian radiotherapy (RT) departments. RESULTS: A total of 37 answered questionnaires returned (36% of all contacts reached), each from different center. 23 centers (62%) presented with dedicated team for IRT treatments, while 15 centers (41%) had dedicated RTT staff. The majority of RTT (86%) did not consider undergraduate training adequate to acquire the skills required to work in IRT departments or units. CONCLUSIONS: This survey underlines the need of additional education and training for RTTs that should focus on treatment management optimization in development of an IRT multi-professional team. Specific updates could be the key to develop further collaboration and to improve cancer patient care.