This study introduces a novel enhanced voxel-by-voxel fused filament fabrication approach utilizing a custom 3D printer. The key innovation is the simultaneous, real-time manipulation of both filament flow and printing speed per voxel. By adjusting the printing speed proportionally to the extrusion rate, the method ensures sufficient time for precise material deposition, effectively countering under-extrusion effects and significantly improving the process’s responsiveness and accuracy. The method was validated through a calibration process and in the fabrication of a breast phantom derived from a patient’s MRI data. Calibration demonstrated a strong linear correlation between HUs, extrusion rate, and speed, with a coefficient of R = 0.99. CT scans of the phantom confirmed consistent replication of the expected HU distribution and anatomical features, visually demonstrating high correlation with the original patient images. The dual-parameter control strategy successfully enhances the fidelity of soft tissue phantoms fabrication. Future work will focus on adapting the method for high-speed printing and multi-material applications.

Introduction: Copeptin is known to be associated with heart damage, while melatonin is a regulatory hormone related to circadian rhythm and represents the levels of inflammation in the body. Methods and Patients: The aim of the study was to measure in different surgeries the levels of copeptin and melatonin at different times before and after surgery in 56 patients aged from 5 days to 13.6 years. We measured copeptin in 50-microL serum and plasma samples from patients before surgery, immediately after surgery, and 24 hours after surgery. The measured levels are aligned with the published GC / MS data, and the sensitivity of the analysis is such that serum and plasma levels can only be measured by rapid extraction. The measurement was made before surgery, immediately after surgery, and 24 hours after surgery. Results: The multifactorial statistical analysis revealed a statistically significant difference between the 24-hour postoperative copeptin values in group 1 (mild-moderate gravity surgery) and group 2 (severe surgery) of the severity of the surgery. Post-hoc tests with Tukey correction for age groups in multiple comparisons of the multifactorial analysis revealed a statistically significant difference (p <0.05) between 24-hour postoperative melatonin values in age groups 3 (3-6 years) and 5 (6-12 years old). The age group 3 showed significantly (p <0.05) lower 24 hours postoperative melatonin values compared to the age group 5 (6-12 years). Again, these 3-6-year-olds were more likely to have inflammation due to the severity of the surgery and the presence of inflammation after the surgery. Discussion: In summary, copeptin is a reliable biomarker for assessing a patient's health both preoperatively and postoperatively. Copeptin and melatonin are two independent agents and are not related to each other, and more studies will be needed with more patients of the same age and with the same underlying disease to assess their diagnostic value. Finally, melatonin could be considered an indicator of inflammation on its own and based on pre-and post-surgery values to determine a patient's health status and take appropriate actions.

Despite the optimal treatment given to children with medulloblastoma, many relapses are seen after combining treatments. Re-irradiation is part of salvage therapy for children who relapse and might provide long-term disease control. Nevertheless, it is challenging because there is a concern about exceeding radiation tolerances and late treatment toxicities. Re-irradiation is an option for many brain tumors, including medulloblastoma in children. This study presents a case of recurrent medulloblastoma treated with re-irradiation. A systematic review of the literature provided up-to-date data on the re-irradiation of medulloblastoma in children. This study aims to contribute to the scarce literature on the treatment strategy, which may help improve patients' outcomes.

Bilateral elective nodal irradiation (ENI) remains standard for treating most head and neck squamous cell carcinomas (HNSCC) but is associated with significant toxicity. Advances in lymphatic mapping, particularly with SPECT/CT-guided sentinel lymph node (SLN) identification, have enabled more personalized radiotherapy strategies. This systematic review evaluates the efficacy and quality-of-life impact of ENI strategies using SPECT/CT-guided SLN mapping. This systematic review, conducted according to PRISMA guidelines, included ten studies published between January 2014 and March 2024, including prospective, retrospective studies, randomized trials, and systematic reviews, examining oncologic outcomes and toxicity in patients undergoing SPECT/CT-guided SLN mapping or individualized ENI. Findings show that in well-lateralized, early stage carcinomas, SPECT/CT-guided ENI safely allows for unilateral treatment in up to 82% of patients, with a low contralateral regional failure rate. This approach significantly reduces radiation exposure to organs at risk and rates of xerostomia, dysphagia, and hypothyroidism, leading to improved quality of life. However, its applicability to advanced or midline tumors remains limited. SPECT/CT-guided SLN mapping and individualized ENI offer a promising, less toxic alternative for selected patients. Further prospective, multicenter, and randomized studies are needed to confirm these benefits and support broader clinical adoption.

Hippocampus protection, as an organ at risk in brain radiotherapy, might protect patients' quality of life. Prophylactic cranial irradiation (PCI) has been used traditionally in small cell lung cancer (SCLC) patients as it increases survival. This study aimed to discover the contributing parameters for a successful PCI with simultaneous protection of the hippocampus by using three different treatment machines. For this purpose, treatment plans were generated for 45 SCLC patients using three half -arcs in three linear accelerators (LINACs; Elekta Infinity, Synergy, and Axesse; Elekta Ltd, Stockholm, Sweden) with different radiation field sizes and multileaf collimator (MLC) leaf thickness characteristics. The prescribed dose was 25 Gy in 10 fractions. Thresholds for the hippocampus were calculated based on the Radiation Therapy Oncology Group 0933 dose constraints. The planning and treatment system templates were common to all three LINACs. Plan evaluation was based on the dosimetric target coverage by the 95% isodose, the maximum dose of the plan, the conformity index (CI), the degree of plan modulation (MOD), and the patient -specific quality assurance (QA) pass rate. The mean target coverage was highest for Infinity (97.3%), followed by Axesse (96.6%) and Synergy (95.5%). The mean maximum dose was higher for Synergy (27.5 Gy), followed by Infinity (27.0 Gy) and Axesse (26.9 Gy). Axesse plans had the highest CI (0.93), followed by Infinity (0.91) and Synergy (0.88). Plan MOD was lower for Synergy (2.88) compared with Infinity (3.07) and Axesse (3.69). Finally, patient -specific QA was successful in all Infinity plans, in all but one Synergy plan, and in 17/45 Axesse plans, as was expected from the field size in that treatment unit. Based on overall performance, the most favorable combination of target coverage, hippocampus sparing, and plan deliverability was obtained with the LINAC, which has the largest field opening and thinnest MLC leaves.

A standard practice in the treatment of patients with small-cell lung cancer (SCLC) is prophylactic cranial irradiation (PCI) to reduce the chance of brain metastases. However, whole brain radiation therapy (WBRT) has been associated with concerns about neurocognitive decline. This has led to the development of WBRT techniques with the simultaneous avoidance of the hippocampus (HA). This article reviews the existing literature on the incidence of hippocampal failure after HA PCI in patients with SCLC. The effort to protect the hippocampus aims to reduce side effects at a cognitive level, but, as reported in various studies, the results regarding safety and effectiveness are ambiguous. Some indicate a higher risk of recurrence in the hippocampal and perihippocampal regions, particularly in non-oligometastatic patients. Despite any concerns, many trials have shown that HA in PCI significantly reduces cognitive decline without compromising overall survival or control of brain metastases. The mixed results noted between studies indicate the necessity of clinical trials to elucidate the benefits and risks of PCI with simultaneous hippocampal protection in patients suffering from SCLC.