International Journal of Radiation Oncology Biology Physics最新文献

Purpose/objectives: There are limited data on outcomes in patients with ultracentral pulmonary oligometastases treated with SABR. The purpose of this study was to determine whether ultracentral location was prognostic for toxicity and survival.

Material and methods: Oligometastatic lung lesions treated on the single-arm phase 2 SABR-5 trial were retrospectively stratified into 2 cohorts: ultracentral tumors (UC), defined as planning target volume overlap or direct tumor abutment to the proximal bronchial tree, esophagus, great vessels, or heart, and nonultracentral tumors. Cohorts were compared with respect to grade ≥ 2 toxicity, progression-free survival (PFS), and overall survival (OS).

Results: In total, 41 patients with 45 ultracentral metastases and 93 patients with 172 nonultracentral metastases underwent SABR. The most common primary histologies were colorectal (30%), lung (13%), and renal (13%), and these did not differ between groups. Patients with UC had a lower median PFS of 5.8 months compared with 15.8 months in patients with non ultracentral tumors (P < .001). OS was also worse in the UC cohort: median 29.0 months versus not yet reached (P < .001). On multivariable regression, UC remained prognostic for worse PFS (hazard ratio 2.18, P = .004) and OS (hazard ratio 3.45, P < .001). Groups had similar rates of local tumor control. Patients with UC had higher 2-year cumulative incidence of polymetastatic progression: 69.2% versus 31.4% (P < .001). The 2-year cumulative incidence of grade ≥ 2 toxicity was 14.6% for patients with UC and 9.8% for patients with nonultracentral tumors (P = .74). There were no grade 4 or 5 toxicities.

Conclusions: In this prospective patient cohort, SABR for ultracentral tumor had low toxicity rates and good local control. However, ultracentral location was an adverse prognostic feature for survival. This finding should be validated with larger studies and may be a factor when weighing the benefit versus risk of SABR in patients with pulmonary oligometastases.

Purpose: We investigated the efficacy and toxicity of thoracic radiation therapy (RT) plus concurrent and consolidation carboplatin with either solvent-based paclitaxel (sb-paclitaxel) or solvent-free nanoparticle albumin-bound paclitaxel (nab-paclitaxel).

Methods and materials: This multicenter phase 1/2 randomized trial included patients with inoperable stage IIIA/B nonsmall cell lung cancer (AJCC 7) and an Eastern Cooperative Oncology Group performance status of 0-1. In phase 1, 6 patients received weekly nab-paclitaxel (50 mg/m²) and carboplatin (AUC 2) with concurrent thoracic RT (60 Gy in 30 fractions), followed by nab-paclitaxel (100 mg/m²) on days 1, 8, and 15 and carboplatin (AUC 6) on day 1 for two 21-day cycles. In phase 2, 92 patients were randomly assigned to weekly sb-paclitaxel (50 mg/m²) or nab-paclitaxel (40 mg/m²) with concurrent RT, followed by consolidation therapy with sb-paclitaxel or nab-paclitaxel and carboplatin for 2 cycles.

Results: Two phase 1 patients had dose-limiting toxicities, setting the phase 2 nab-paclitaxel dose at 40 mg/m². For the phase 2 cohort, 2-year overall survival was 67% for sb-paclitaxel and 56% for nab-paclitaxel (P = .10), with progression-free survival of 44% and 27%, respectively (P = .14). Fewer patients completed consolidation with nab-paclitaxel (26%) versus sb-paclitaxel (58%) (P = .005). Grade 3 and higher adverse events were more frequent with nab-paclitaxel (56%) than with sb-paclitaxel (30%) (P = .029).

Conclusions: Nab-paclitaxel was associated with higher toxicity and numerically lower efficacy than sb-paclitaxel when used with thoracic radiation in locally advanced nonsmall cell lung cancer.

Purpose: A previous, individual patient-level meta-analysis of randomized controlled trials (RCTs) demonstrated the overall survival (OS) benefit of short-term androgen deprivation therapy (ST-ADT) when delivered with radiation therapy (RT) for the subset of patients with intermediate-risk prostate cancer (IR-PCa). However, because of inclusion criteria, several studies such as NRG/RTOG 0815, GETUG-14, and DFCI 95-096 were excluded. Thus, we conducted the present analysis, inclusive of all studies to define the current role of ST-ADT in IR-PCa.

Methods and materials: A systematic review was conducted of phase 3 RCTs published or presented between January 1980 and October 2024 which profiled the comparative efficacy of radiation therapy ± ST-ADT in patients with IR-PCa. A study-level, random-effects meta-analysis was performed. The primary endpoint of this meta-analysis was OS, with secondary endpoints of time-to-biochemical failure (BF) ± biochemical-progress-free survival (bPFS). Meta-regression was used to explore trial-level factors associated with treatment effects. Synthetic individual patient-level OS data were pooled for confirmation and used to estimate the relative and absolute survival benefit.

Results: Seven RCTs (NRG/RTOG 9408, DFCI 95-096, TROG 96.01, PCS III, EORTC 22991, NRG/RTOG 0815, and GETUG-14) reporting outcomes of 6179 patients were identified. The pooled hazard ratios (HRs) for HR_OS, HR_BF, and HR_BF+bPFS were 0.88 (95% confidence interval [CI], 0.79-0.97; P = .01), 0.50 (95% CI, 0.37-0.68; P < .001), and 0.54 (95% CI, 0.46-0.65; P < .001), respectively. ST-ADT duration, RT dose, and Gleason score trial population composition were each associated with an increased benefit of ST-ADT for biochemical disease control (all P < .05) but not for OS (all P > .05). Pooling of simulated, patient-level data confirmed the presence of a survival benefit (HR_OS, 0.85 [95% CI, 0.76-0.96], log-rank P = .021), corresponding to an absolute survival benefit of 5% benefit at 10 years.

Conclusions: The present analysis confirms current knowledge that ST-ADT improves both OS and prostate-specific antigen-based outcomes for unselected patients with IR-PCa to a clinically significant degree.

Purpose: To evaluate the toxicities and survival outcomes associated with carbon ion radiation therapy (CIRT) using pencil beam scanning (PBS) technique and to assess the prognostic factors for patients with stage III non-small cell lung cancer (NSCLC) using a local effect model (LEM)-based biological dose calculation.

Methods and materials: This analysis included patients with stage III NSCLC (n = 181) who received CIRT between December 2016 and June 2023. CIRT was administered at a relative biological effectiveness-weighted dose of 77 Gy (range, 69-83.6 Gy) in 22 fractions (Fx) (range, 19-24 Fx). Most patients (96.1%) underwent systemic therapy before and/or after CIRT. Toxicities and survival outcomes were recorded, and statistical analyses conducted.

Results: The median follow-up period was 18.2 months. Grade 1, 2, 3, and 4 acute toxicities were observed in 62.4%, 30.4%, 2.8%, and 0.6% of patients, respectively, with hematological toxicities accounting for all grade ≥ 3 acute toxicities. Grade 1, 2, 3, and 4 late toxicities occurred in 40.3%, 30.9%, 4.4%, and 1.7% of patients, respectively, with most grade ≥ 3 CIRT-induced late toxicities (72.7%) observed in patients receiving a CIRT dose ≥ 79.2 Gy. The median overall survival (OS) and progression-free survival (PFS) were 37.1 and 16.7 months, respectively. The 2-year locoregional control, OS, PFS, and distant metastasis-free survival rates were 66.1%, 64.2%, 40.3%, and 49.5%, respectively. Patients who received a CIRT dose ≤ 77 Gy had better OS (P = .047), but worse locoregional control compared with those who received higher doses (P = .026). Post-CIRT immunotherapy was an independent prognostic factor for improved OS, distant metastasis-free survival, and PFS (P = .002, P < .001, and P < .001, respectively).

Conclusions: CIRT with pencil beam scanning was effective for locally advanced NSCLC, resulting in acceptable toxicities and promising OS outcomes, particularly with doses of 69 to 77 Gy and post-CIRT immunotherapy.

Purpose: The integration of advanced imaging and artificial intelligence technologies in radiation therapy has revolutionized cancer treatment by enhancing precision and adaptability. This study introduces a novel dual-energy computed tomography (DECT) guided intelligent radiation therapy (DEIT) platform designed to streamline and optimize the radiation therapy process. The DEIT system combines DECT, a newly designed dual-layer multileaf collimator, deep learning algorithms for auto-segmentation, and automated planning and quality assurance capabilities.

Methods and materials: The DEIT system integrates an 80-slice computed tomography (CT) scanner with an 87 cm bore size, a linear accelerator delivering 4 photon and 5 electron energies, and a flat panel imager optimized for megavoltage (MV) cone beam CT acquisition. A comprehensive evaluation of the system's accuracy was conducted using end-to-end tests. Virtual monoenergetic CT images and electron density images of the DECT were generated and compared on both phantom and patient. The system's auto-segmentation algorithms were tested on 5 cases for each of the 99 organs at risk, and the automated optimization and planning capabilities were evaluated on clinical cases.

Results: The DEIT system demonstrated systematic errors of less than 1 mm for target localization. DECT reconstruction showed electron density mapping deviations ranging from -0.052 to 0.001, with stable Hounsfield unit consistency across monoenergetic levels above 60 keV, except for high-Z materials at lower energies. Auto-segmentation achieved dice similarity coefficients above 0.9 for most organs with an inference time of less than 2 seconds. Dose-volume histogram comparisons showed improved dose conformity indices and reduced doses to critical structures in auto-plans compared to manual plans across various clinical cases. In addition, high gamma passing rates at 2%/2 mm in both 2-dimensional (above 97%) and 3-dimensional (above 99%) in vivo analyses further validate the accuracy and reliability of treatment plans.

Conclusions: The DEIT platform represents a viable solution for radiation treatment. The DEIT system uses artificial intelligence-driven automation, real-time adjustments, and CT imaging to enhance the radiation therapy process, improving efficiency and flexibility.

Background: Conventionally fractionated radiotherapy (CFRT) and hypofractionated radiotherapy (HFRT) are established treatments for intermediate-risk (IR) prostate cancer (PCa), with differing dose per fraction. Yet, their comparative patterns of failure remain unclear.

Objective: To analyze the distinct relapse patterns of HFRT versus CFRT in terms of local progression-free survival (LPFS), pelvic lymph node metastasis-free survival (pnMFS), extra-pelvic lymph node MFS (epnMFS), and bone MFS.

Design, setting, and participants: Patients with IR PCa included in French and Australian centers in the "PROstate Fractionated Irradiation Trial (PROFIT)" study (NCT00304759), a phase 3, multicenter, randomized controlled trial.

Intervention: Using molecular PET imaging, MRI and bone scintigraphy, the anatomical sites of relapse were retrospectively identified in biochemically relapsing patients following HFRT or CFRT.

Outcome measurements and statistical analysis: LPFS, pnMFS, epnMFS, bMFS were compared between both treatment arms using Kaplan-Meier analyses.

Results and limitations: With a median follow-up of 6.4 years, 274 patients (130 HFRT; 144 CFRT) were included, among whom 35 (24.3%) in the HFRT arm and 28 (19.4%) in the CFRT arm experienced relapse. Median time to relapse varied by site: 4.9 years locally, 3.96 years for pelvic lymph nodes, 2.95 years for extra-pelvic lymph nodes, and 3.6 years for bone metastasis. No significant differences were found between HFRT and CFRT arms in LPFS, pnMFS, epnMFS, or bMFS.

Conclusion: Relapse rates following HFRT or CFRT are low, with no discernible variance in anatomical relapse patterns between treatments. Tailored management strategies considering these relapse patterns could optimize care of IR patients, including initial staging and microboosting of dominant lesions.