Citations

Abstract Additive manufacturing (AM), commonly referred to as 3D printing, has been broadly used in the field of medical imaging and radiotherapy. In medical imaging applications, patient‐specific anatomic models have been used to aid in preoperative planning, patient communication, imaging technique assessment and optimization, and medical education. Within the field of radiation therapy, 3D printing finds significance in fabricating patient‐specific immobilization devices, custom bolus devices, anthropomorphic phantoms, brachytherapy devices, and electron therapy devices. Consistent with standard medical physics practices there is a need to establish quality assurance and quality control (QA/QC) protocols, tolerances, and testing frequencies. The diversity of 3D printing technologies and products poses challenges for medical adoption and thus requires guidelines in workflow standardization and establishment of testing procedures. This report is centered around providing comprehensive vendor‐neutral implementation guidelines and recommendations for QC and QA processes. The scope of this report encompasses diverse requirements within medical imaging and radiation therapy settings, serving both clinical and research purposes. Brief overview of 3D printing technology, common materials, and potential clinical applications is provided. QA team, infrastructure, measurement techniques and challenges are discussed. QA processes for each step in 3D printing are discussed in great detail and baseline and action limits are recommended. This report also touched on regulatory considerations. Key recommendations are summarized at the end of the report.

Background/Objectives: Hypofractionated ablative radiation is an increasingly popular option for patients with hepatocellular carcinoma (HCC). However, concern remains about the risk for radiation-induced liver toxicity in patients with decompensated liver function. Methods: We retrospectively identified patients with underlying Child-Pugh (CP) B or C liver function treated at our University and Veterans Affairs (VA) departments from 2014 to 2019. Primary endpoints included treatment-related toxicity and dosimetric parameters. Results: 38 patients were included in the analysis. Most patients (98%) had CP B or Albumin-Bilirubin (ALBI) grade 2–3 (100%) liver disease. The median dose was 50 Gy (range 30–50) delivered in 5 or 10 fractions. Most patients had a single tumor treated (66%) with a median size of 3.1 cm (Interquartile Range (IQR) 2.3–4.1). The mean liver dose was 9.28 Gy (IQR 6.76–13.64) with a liver D800cc of 3.99 Gy (IQR 1.41–8.02). All patients completed their intended course with a median follow-up of 43 months. Four patients (10.3%) developed non-classical radiation-induced liver disease (RILD), comparable to the rate for patients with CP A function treated contemporaneously (8.3%). Otherwise, one patient (2.6%) experienced acute grade 3+ (non-RILD) hepatobiliary toxicity, while one patient (2.6%) experienced late grade 3+ hepatobiliary toxicity. Local control was promising with 2-year freedom from progression in the treated lesion of 73% (95% CI 38–91%). Median overall survival was 12 months (95% CI 5–25 months). Conclusions: Ablative radiation for patients with decompensated liver function and HCC appears well tolerated with low rates of RILD and encouraging local control. With careful selection, these patients should be considered for inclusion in future randomized trials.

PURPOSE Previous studies suggest that SPOP mutations result in increased sensitivity to androgen receptor pathway inhibitors (ARPIs) but are limited by lack of granular data. We hypothesize that SPOP mutations are associated with improved outcomes across the spectrum of advanced prostate cancer (PC). METHODS Using the real-world clinicogenomic Prostate Cancer Precision Medicine Multi-Institutional Collaborative Effort database, we analyzed outcomes based on SPOP mutation status. The primary end point was overall survival (OS) from the diagnosis of metastatic disease. Secondary end points included real-world progression-free survival (PFS) and PSA90 response. RESULTS Among 2,097 patients with metastatic PC, 5.5% (N = 115) had SPOP -mutated tumors. Compared with SPOP wild-type, patients with SPOP mutations were older at diagnosis (median 65 v 63 years; P = .001) and had higher (≥8) Gleason sum (68% v 54%; P = .02), higher incidence of lung metastasis (17% v 6%; P = .001), and increased frequency of intraductal features (13% v 5%; P < .001). SPOP mutations were associated with improved PSA90 response with first ARPI exposure in the castrate-resistant setting (60% v 40.6%; OR, 2.20 [95% CI, 1.15 to 4.19]; P = .02) but not in the castrate-sensitive setting (78.9% v 71.5%; OR, 1.49 [95% CI, 0.66 to 3.37]; P = .43). Median PFS with first ARPI did not differ in SPOP- mutated versus wild-type group in both the castrate-sensitive (24.2 v 19.2 months; hazard ratio [HR], 0.80 [95% CI, 0.49 to 1.32]; P = .39) and castrate-resistant settings (15.0 v 12.4 months; HR, 0.81 [95% CI, 0.58 to 1.12]; P = .20). In multivariable analysis, SPOP mutations were associated with improved OS (HR, 0.65, P = .02). CONCLUSION SPOP mutations were associated with longer OS despite the presence of aggressive clinical features. The distinct clinical and molecular features of SPOP -mutated PC support its consideration as a unique molecular subtype with prognostic implications.

Background: The AFFINITY trial (NCT05890872) is a prospective, non-randomized, open-label, single-arm study evaluating the safety, immunological impact, and preliminary efficacy of Aliya pulsed electric field ablation in patients with solid tumors. Thirty-one patients were enrolled; thirty received lung lesion ablation prior to continuation on standard-of-care treatment. This manuscript reports six-month local control outcomes and immunological response characteristics. Radiological outcomes were assessed using a modified RECIST 1.1, and immunological impact was evaluated via changes in peripheral blood immunocyte populations and detection of immunoglobulins (Ig) to tumor-associated antigens in serum post-ablation. Methods: Twenty-eight patients underwent radiological assessment of ablated lesions at approximately 1-, 3-, and 6-month post-ablation to evaluate local control. Peripheral blood was collected for immune monitoring using flow cytometry and to detect IgG responses to biopsy-specific and tumor-associated antigens. Results: At 6 months, two cohorts emerged: 12 received ablation only, and 16 received ablation plus systemic and/or focal therapies (radiotherapy or second ablation). In the ablation-only group, imaging showed local control in all ablated lesions (8/12 SD, 4/12 PR), suggesting local efficacy without systemic therapy in those patients. Immunophenotyping showed dynamic changes in circulating immune cells, including T and B cell activation. A subset also exhibited modulation of tumor antigen-specific IgG, indicating a systemic humoral response. Conclusions: This analysis provides preliminary evidence that this form of ablation may promote local tumor control and modulate systemic immune function. These findings support the immunogenic potential of this specialized energy and warrant further investigation. Extended 12-month data for the full cohort will be reported in a future manuscript.

Respiratory muscle fatigue could occur following involuntary breathing movements during maximal breath-holds. We measured respiratory muscle strength pre and post three preparatory and maximal breath-holds. We found significant reductions in diaphragm strength and total inspiratory and expiratory strength in some, but not all, divers. Divers that had respiratory muscle fatigue had a lower pseudo O 2 delivery (HR × [Formula: see text]) during the struggle phase. This suggests that reduced oxygen delivery may contribute to respiratory muscle fatigue during a breath-hold.

AbstractThis article investigates the performance of a commercial BeO optically stimulated luminescent (OSL) dosimetry system (myOSLchip, RadPro GmbH International, Remscheid, Germany) through the application of the commissioning framework for luminescent dosimeters as described in the American Association of Physicists in Medicine Task Group 191 (AAPM TG191) report. Initial clinical experiences and dosimetric results are also presented. The following properties of the system were characterized: linearity correction factors ranged from ‐0.5% to +3% for dose levels spanning 0.1 to 20 Gy. Beam quality correction factors (relative to 6 MV) ranged from ‐4.5% (2.5FFF) to +4.5% (15MV) for photon beams and +1.9% (6 MeV) to +4.3% (20 MeV) for electron beams. An average (µ) signal loss per reading of ‐2.13% ± 0.20% was measured, however greater signal loss was observed in the first reading (µ = ‐2.6% ± 0.46%). An initial decline in individual element sensitivity relative to baseline was observed from 0–15 Gy cumulative dose (µ = ‐1.98% ± 0.55%), with negligible further deterioration from 15–32 Gy (µ = ‐2.38% ± 0.85%). Post‐irradiation, there was a transient OSL signal which faded with a half‐life of 1.8 min; this signal enhancement was +5% at 5 min post‐irradiation and +1% at 15 min relative to 24 h. Dosimeter response was not dependent on average dose rate in the range of 100–2500 MU/min. With respect to clinical testing, equal or superior performance compared with aluminum oxide OSLs (nanoDots) is shown for a range of clinical techniques and modalities including TSET, TBI, en‐face electrons, and pacemaker/out‐of‐field measurements. The feasibility of myOSLchip to serve as a primary clinical in vivo dosimetry system and direct replacement for Landauer's microStar system is demonstrated.

This article addresses clinical challenges of photon-counting detector (PCD) CT in pediatric patients by outlining fundamental terminology, explaining technical aspects, and providing protocol guidance for the first commercially available PCD CT scanner.

Introduction: Advanced age is a risk factor for poor outcomes following left ventricular assist device (LVAD) implant. A means of identifying elderly patients with acceptable mortality risk following LVAD surgery is not currently available. The HeartMate II (HMII) Risk Score (HMRS) was recently developed and validated, providing good risk discrimination for predicting survival in patients undergoing HMII implant. Independent survival predictors in the model included age and markers of renal function, coagulopathy and nutrition. We hypothesize that the HMRS will provide utility for risk stratification of the elderly LVAD candidate. Methods: Elderly patients (age >65 years) enrolled into the HMII Destination Therapy (DT) and Bridge to Transplant trials were selected for the study (n=444). Complete data for HMRS calculation was available in 98% (n=435). Preoperative patient HMRS was calculated according to the formula: HMRS = ln(1.29)*decade of age + ln(0.71)*Albumin + ln(1.37)*Cr + ln(1.86)*INR + ln(0.52)*LVAD Center Volume >=15 + ln(0.67)*Implant after 2007. Patients were trichotimized into high (HMRS >1.0), medium (HMRS 0.50-1.0), and low (HMRS <=0.50) risk categories (as previously defined in model development) based on HMRS. The primary endpoint was survival at 1 year following LVAD implant, estimated using Kaplan-Meier methods. Results: The mean cohort age was 71±4 years and 84% (n=372) had devices implanted for DT. The table shows the HMRS along with mean±stddev values for the score's components. All between-group differences were statistically significant (Kruskal-Wallis p<0.05), although differences in age were not clinically significant. Survival based on HMRS strata is shown in the figure. Patients in the low and medium risk groups had survivals >80% at 1 year following LVAD implant. Conclusions: The HMRS can be used to identify elderly patients with survivals comparable to that of the general LVAD population.

Chronic myeloid leukemia (CML) is defined by the presence of Philadelphia chromosome resulting from a reciprocal translocation between chromosomes 9 and 22 [t9;22] that gives rise to a BCR::ABL1 fusion gene. CML occurs in 3 different phases (chronic, accelerated, and blast phase) and is usually diagnosed in the chronic phase in developed countries. Tyrosine kinase inhibitor (TKI) therapy is a highly effective treatment option for patients with chronic phase–CML. The primary goal of TKI therapy in patients with chronic phase–CML is to prevent disease progression to accelerated phase–CML or blast phase–CML. Discontinuation of TKI therapy with careful monitoring is feasible in selected patients. This manuscript discusses the recommendations outlined in the NCCN Guidelines for the diagnosis and management of patients with chronic phase–CML.