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PurposePatients with centrally located early-stage non-small-cell lung cancer (NSCLC) are at a higher risk of toxicity from high-dose ablative radiotherapy. NRG Oncology/RTOG 0813 was a phase I/II study designed to determine the maximum tolerated dose (MTD), efficacy, and toxicity of stereotactic body radiotherapy (SBRT) for centrally located NSCLC.Materials and methodsMedically inoperable patients with biopsy-proven, positron emission tomography-staged T1 to 2 (≤ 5 cm) N0M0 centrally located NSCLC were accrued into a dose-escalating, five-fraction SBRT schedule that ranged from 10 to 12 Gy/fraction (fx) delivered over 1.5 to 2 weeks. Dose-limiting toxicity (DLT) was defined as any treatment-related grade 3 or worse predefined toxicity that occurred within the first year. MTD was defined as the SBRT dose at which the probability of DLT was closest to 20% without exceeding it.ResultsOne hundred twenty patients were accrued between February 2009 and September 2013. Patients were elderly, there were slightly more females, and the majority had a performance status of 0 to 1. Most cancers were T1 (65%) and squamous cell (45%). Organs closest to planning target volume/most at risk were the main bronchus and large vessels. Median follow-up was 37.9 months. Five patients experienced DLTs; MTD was 12.0 Gy/fx, which had a probability of a DLT of 7.2% (95% CI, 2.8% to 14.5%). Two-year rates for the 71 evaluable patients in the 11.5 and 12.0 Gy/fx cohorts were local control, 89.4% (90% CI, 81.6% to 97.4%) and 87.9% (90% CI, 78.8% to 97.0%); overall survival, 67.9% (95% CI, 50.4% to 80.3%) and 72.7% (95% CI, 54.1% to 84.8%); and progression-free survival, 52.2% (95% CI, 35.3% to 66.6%) and 54.5% (95% CI, 36.3% to 69.6%), respectively.ConclusionThe MTD for this study was 12.0 Gy/fx; it was associated with 7.2% DLTs and high rates of tumor control. Outcomes in this medically inoperable group of mostly elderly patients with comorbidities were comparable with that of patients with peripheral early-stage tumors.

Simple Summary: The very poor prognosis and the absence of radical treatment options in cases of unresectable "locally advanced pancreatic cancer (LAPC)" focus its management on palliation. An "overall survival (OS)" benefit has been shown with new systemic therapy agents; however, not all patients are good candidates for systemic treatments at diagnosis, and LAPC is often associated with a high symptom burden that greatly impacts patients' quality of life. Studying dose optimization of radiation as an option for local progression cessation is therefore necessary. Research in this setting as opposed to other treatment sites is under-represented in the literature and the guidelines are based on very scarce data. We aim to present the outcomes of "stereotactic body radiotherapy (SBRT)" (ablative radiotherapy) vs. non-ablative radiotherapy through our patient population and the available data in the literature. We studied the dose–local control (LC) relationship in ablative vs. non-ablative radiotherapy in a non-radical treatment setting of "locally advanced pancreatic cancer (LAPC)" by comparing our patients (n = 89) treated with SBRT on the CyberKnife unit vs. conventional radiation between January 2005 and January 2021, and by reviewing the literature. A systematic search was performed leveraging Medline for references on SBRT use in pancreatic cancer without date terms or language restrictions. A total of 3702 references were identified and the search was then repeated in Embase and the Cochrane database. Ultimately, 12 studies were eligible for inclusion, which either compared SBRT to conventional radiation, or SBRT use in dose escalation for primary LAPC in a non-neoadjuvant setting. Our cohort's median overall survival was 152 days (CI 95%, 118–185); including 371 days (CI 95%, 230–511) vs. 126 days (CI 95%, 90–161) favoring SBRT, p = 0.004. The median time to local progression was 170 days (48–923) for SBRT vs. 107 days (27–489) for the non-ablative group. In our SBRT patients, no local progressions were seen with BED10 > 60 Gy. Even when palliating LAPC, SBRT should be considered as an alternative to conventional radiation, especially in patients with a low disease burden. BED10 ≥ 60–70 Gy offers better local control without increasing toxicity rates. Less local progression may provide a better quality of life to those patients who already have a short life expectancy. [ABSTRACT FROM AUTHOR]

Background: To assess correlation of pretreatment specific growth rate (SGR) value of 0.43 × 10‐2 with overall and failure‐free survival of patients with early‐stage non‐small cell lung cancer (NSCLC) treated with stereotactic body radiation therapy (SBRT). Methods: A retrospective chart review of 160 patients with pathologically confirmed stage I NSCLC treated with SBRT between June 2010 and December 2012 in a large, tertiary cancer institute was undertaken. Both diagnostic and archived planning CT were uploaded to the treatment planning system to determine tumor volume at diagnosis (GTV1) and planning time (GTV2). The time (t) between both CTs was recorded. SGR was calculated using GTV1, GTV2, and t. The median SGR (0.43 × 10‐2) from our previous data was used to group patients into low and high SGR cohorts. Log‐rank test was used to compare overall (OS) and failure‐free survivals (FFS) of SGR groups. Results: The median time interval between diagnostic and planning CT scans was 87 days. The median OS was 38 and 66 months for high and low SGR cohorts, respectively (P = 0.03). The median FFS was 27 and 55 months for high and low SGR cohorts, respectively (P = 0.005). High SGR (P < 0.05), male gender (P = <0.01), and GTV2 (P = <0.05) were associated with poorer FFS. Conclusions: High SGR was associated with poorer outcome in patients with early‐stage NSCLC treated with SBRT. SGR can be used in conjunction with other well‐known predictive factors to formulate a practical predictive model to identify subgroups of the patient at higher risk of recurrence after SBRT. [ABSTRACT FROM AUTHOR]

Background and Purpose: The purpose of this study is to review our experience with platinum fiducials in terms of feasibility of placement and detectability by both MRI and orthogonal x-ray images used in robotic SABR. Materials and Methods: 29 consecutive SABR patients (30 tumors) treated using fiducial tracking between January 2011 and February 2012 were reviewed. A total of 108 fiducials implanted in or around various tumor sites were identified. The pixel value contrast (PVC) of fiducials seen on MRI mages and treatment unit x-ray images of patients and phantoms were analysed. Results: Migration rates were similar for PS versus GS and GC (6.2%). No difference was noted between the mean PVC in cirrhotic versus non-cirrhotic liver (60.4 vs. 47.9; p = 0.074). MRI sequences for tumors in the liver and other organs revealed a mean PVC for platinum superior to that of gold (p<0.001). No PVC difference was seen between gold and platinum on analysis of the treatment unit x-rays. Conclusion: Platinum seeds provide a superior detectability in comparison to gold seeds or coils on MRI images and are detected equally well by an image guidance system using orthogonal x-rays, making them a better choice for fiducial-based CT-MRI registration. [ABSTRACT FROM AUTHOR]

The prognosis of patients with metastatic liver disease remains dismal with a median survival of only 6-12 mo. As 80%-90% of patients are not candidates for surgical therapy, there is a need for effective non-surgical therapies that would improve outcomes in these patients. The body of evidence related to the use of stereotactic ablative radiotherapy (SABR) in metastatic liver disease has substantially grown and evolved over the past decade. This review summarizes the current evidence supporting liver SABR with particular attention given to patient selection, target delineation, organ at risk dose volume constraints, response evaluation imaging and the various SABR techniques for delivering ablative radiotherapy to the liver. Even though it is unclear what dose-fractionation scheme, delivery system, concomitant therapy or patient selection strategy yields the optimum liver SABR outcomes, clear and growing evidence is available that SABR is a safe and effective therapy for the treatment of oligometastatic liver disease.