BACKGROUND:Process mining (PM) is a powerful approach for analysing and optimising complex workflows. Radiation therapy (RT) involves multiple steps and resources, making it well suited for PM analysis.This study aims to apply a PM approach to characterise the real-world workflow of a high-volume RT department, with the goal of identifying critical transitions and bottlenecks, quantifying their impact on treatment timelines, and exploring the main factors associated with treatment suspensions and cancellations. MATERIAL AND METHODS:Patients treated with RT at our centre between January 2017 and December 2021 were included. All patient-related events were extracted from the institutional database. A first-order Markov model was used to analyse event sequences and identify anomalies, while the Kruskal-Wallis test compared median completion times across stratified sub-cohorts. RESULTS:The study analysed 43,183 events associated with 8608 treatments. The pathway diagram depicted key events, such as Prescription, Scheduling, CT simulation, RT start, RT cancelled, RT suspension, and RT end. Statistical analysis revealed a significant difference in terms of median time in case of suspension event during the path, leading to a delay in the start of RT treatment (p<0.05). The analysis of the employed time from Prescription to RT start demonstrated a significant impact of suspension on the time interval for breast, genitourinary, gastrointestinal, metastatic, head and neck, gynaecological, thoracic, and skin cancer (p<0.05). CONCLUSIONS:This study illustrates the applicability of PM as a methodological framework for analysing care pathways. By demonstrating how PM can identify delays, interruptions, and workflow inefficiencies, it highlights its potential to support process evaluation and optimisation.

AIMS:Ventricular tachycardia (VT) in patients with structural heart disease can be life-threatening and may persist despite anti-arrhythmic therapy and catheter ablation. When standard treatments are ineffective or contraindicated, stereotactic arrhythmia radioablation (STAR) has emerged as a non-invasive salvage option. METHODS AND RESULTS:This prospective, single-centre study included 19 patients with structural heart disease and recurrent VT unresponsive to conventional therapy and who were ineligible for ablation. Patients were selected by a multidisciplinary team and underwent cardiac CT and electroanatomic mapping for substrate characterization. STAR was delivered in a single 25 Gy fraction using volumetric modulated arc therapy. Primary endpoints included safety (adverse events within 12 months) and efficacy (reduction in VT burden, assessed by ICD-recorded anti-tachycardia pacing [ATP] and shocks). During a median follow-up of 14 months [IQR 9-15], STAR was associated with a significant reduction in ICD therapies, with an average decrease of 81%. Mean ATP interventions/month dropped from 4.5 ± 6.5 to 0.8 ± 2.3 (P = 0.029), and total ICD therapies/month decreased from 4.8 ± 7.0 to 0.9 ± 2.5 (P = 0.032). Mild pulmonary injury and pericardial effusion occurred in 22.2% of patients. Most cases were asymptomatic; one patient (5.5%) required non-urgent pericardiocentesis. No significant changes in left ventricular function, valvular status, or coronary artery disease progression (assessed by CAD-RADS and PCAT analysis) were observed. One-year mortality was 33.3%; no deaths were directly attributable to STAR. CONCLUSION:STAR shows promise as a safe, non-invasive option for patients with refractory VT and advanced cardiomyopathy. Larger multicentre studies are needed to confirm long-term outcomes and better define its clinical role.

In this technical development report, we present the strategic placement of fiducial markers within the prostate under the guidance of computed tomography (CT) and electromagnetic navigation (EMN) for the delivery of ultra-hypofractionated cyberknife (CK) therapy in a patient with localized prostate cancer (PCa) who had previously undergone chemo-radiotherapy for rectal cancer and subsequent abdominoperineal resection due to local recurrence. The patient was positioned in a prone position with a pillow under the pelvis to facilitate access, and an electromagnetic fiducial marker was placed on the patient's skin to establish a stable position. CT scans were performed to plan the procedure, mark virtual points, and simulate the needle trajectory using the navigation system. Local anesthesia was administered, and a 21G needle was used to place the fiducial markers according to the navigation system information. A confirmatory CT scan was obtained to ensure proper positioning. The implantation procedure was safe, without any acute side effects such as pain, hematuria, dysuria, or hematospermia. Our report highlights the ability to use EMN systems to virtually navigate within a pre-acquired imaging dataset in the interventional room, allowing for non-conventional approaches and potentially revolutionizing fiducial marker positioning, offering new perspectives for PCa treatment in selected cases.

The strategy to anticipate radiotherapy (RT) before surgery, for breast cancer (BC) treatment, has recently generated a renewed interest. Historically, preoperative RT has remained confined either to highly selected patients, in the context of personalized therapy, or to clinical research protocols. Nevertheless, in the recent years, thanks to technological advances and increased tumor biology understanding, RT has undergone great changes that have also impacted the preoperative settings, embracing the modern approach to breast cancer. In particular, the reappraisal of preoperative RT can be viewed within the broader view of personalized and tailored medicine. In fact, preoperative accelerated partial breast irradiation (APBI) allows a more precise target delineation, with less variability in contouring among radiation oncologists, and a smaller treatment volume, possibly leading to lower toxicity and to dose escalation programs. The aim of the present review, which represents a benchmark study for the AIRC IG-23118, is to report available data on different technical aspects of preoperative RT including dosimetric studies, patient’s selection and set-up, constraints, target delineation and clinical results. These data, along with the ones that will become available from ongoing studies, may inform the design of the future trials and representing a step toward a tailored APBI approach with the potential to challenge the current treatment paradigm in early-stage BC. Trial registration: The study is registered at clinicaltrials.gov (NCT04679454).

The aim is to evaluate the feasibility of ultra-hypofractionated (UH) SBRT with CyberKnife® (CK) radiosurgery (Accuray Inc., Sunnyvale, California, USA) for localized prostate cancer (PCa) with a concomitant focal boost to the dominant intraprostatic lesion (DIL). Patients with intermediate/high-risk PCa, with at least one visible DIL on multi-parametric MRI, were included. For each, two CK-SBRT in silico plans were calculated using 95% and 85% isodose lines (CK-95%, CK-85%) and compared with the UH-DWA plan delivered with VERO®. All plans simulated a SIB prescription of 40 Gy to PTV-DIL and 36.25 Gy to the whole prostate (PTV-prostate) in five fractions every other day. Fifteen patients were considered. All plans reached the primary planning goal (D95% > 95%) and compliance with organs at risk (OARs) constraints. DVH metrics median values increased (p < 0.05) from UH-DWA to CK-85%. The conformity index of PTV-DIL was 1.00 for all techniques, while for PTV-prostate was 0.978, 0.984, and 0.991 for UH-DWA, CK-95%, and CK-85%, respectively. The CK-85% plans were able to reach a maximum dose of 47 Gy to the DIL while respecting OARs constraints. CK-SBRT plus a focal boost to the DIL for localized PCa appears to be feasible. These encouraging dosimetric results are to be confirmed in upcoming clinical trials such as the phase-II “PRO-SPEED” IEO trial.