Radiation Oncology最新文献

Background: A predictive assay for late radiation toxicity would allow more personalized treatment planning, reducing the burden of toxicity for the more sensitive minority, and improving the therapeutic index for the majority. In a previous study in prostate cancer patients, the γ-H2AX foci decay ratio (γ-FDR) was the strongest predictor of late radiation toxicity. The current study aimed to validate this finding in a more varied group of patients with pelvic cancer. Additionally, the potential correlation between the γ-FDR and patient-reported outcomes was investigated.

Methods: Prostate and gynecological cancer patients with ≥ 24 months of follow-up were included in the current analysis. Toxicity was evaluated by physician (CTCAE version 4) and patient (EORTC questionnaires). γ-FDRs were determined in ex vivo irradiated lymphocytes. Correlation between γ-FDR and toxicity was assessed using both linear and logistic regression analyses. The highest toxicity grade recorded during follow-up was used. The association between global quality of life and γ-FDR was tested by comparing the change in quality of life over time in patients with γ-FDR < or ≥ 3.41, a previously established threshold.

Results: Eighty-eight patients were included. Physician-assessed and patient-reported cumulative grade ≥ 2 toxicity was 25% and 29%, respectively; which is much lower than in the previous cohort (i.e., 51% CTCAE grade ≥ 2). Patients with toxicity exhibited less favorable dose-volume parameters. In men, these parameters showed significant improvement compared to the previous cohort. The proportion of patients with a low γ-FDR increased with severity of toxicity, but this trend was not statistically significant. In addition, a γ-FDR < 3.41 was not correlated with the development of moderate to severe toxicity. Post-treatment decline in global quality of life was minimal, and similar for patients with γ-FDR < or ≥ 3.41.

Conclusions: In the present study, the γ-H2AX foci decay ratio could not be validated as a predictor of late radiation toxicity in patients with pelvic cancer. Improved radiotherapy techniques with smaller irradiated bladder and bowel volumes have probably resulted in less toxicities. Future studies on genetic markers of toxicity should be powered on these lower incidences. We further recommend taking persistency, next to severity, into consideration.

Objective: Explore the efficacy and safety of involved-field irradiation (IFI) combined with S-1 as definitive concurrent chemoradiotherapy (dCRT) for locally advanced elderly esophageal squamous cell carcinoma (ESCC), under the premise of intensity-modulated radiotherapy (IMRT).

Methods: We designed a prospective single-arm phase II study. The study enrolled 91 patients aged 75 to 92 years. Eligible participants had histologically confirmed squamous cell carcinoma, stage II to IV disease based on the 8th edition of the American Joint Committee on Cancer (AJCC). All elderly patients (EPs) received dCRT with S-1. which was administered orally twice daily for 28 days. The radiotherapy dose was 61.2 Gy delivered in 34 fractions or 50.4 Gy delivered in 28 fractions. The primary endpoint was 2-year overall survival (OS), and the secondary endpoints were progression-free survival (PFS), local control rate (LCR), and safety.

Results: From July 2017 to July 2021, we enrolled EPs with ESCC who were treated at the Jiangsu Cancer hospital. As of August 1, 2023, the median follow-up of surviving EPs was 31.4 months (IQR: 25.2 to 72.6 months). 83 patients (91.2%) completed the whole course of treatment. The 2-year OS rate was 59.2%, and the PFS rate was 43.7%. The most common grade 1 to 2 adverse effects (AEs) were radiation esophagitis (79.1%), and then were radiation pneumonia (46.2%). Anemia (41.8%) was the most common of grade 1 to 2 hematologic toxicity. The incidence of grade 3 or above AEs was 24.2%, and the incidence of leukopenia was the highest (11.0%). There was not one death due to treatment-related toxicity. In a subgroup analysis of radiotherapy doses, we found no statistically significant differences in PFS (P = 0.465) and OS (P = 0.345) in EPs with ESCC who received 50.4 Gy and 61.2 Gy, and that patients in the 50.4 Gy group had lower dermatitis (P = 0.045) and anemia (P = 0.004).

Conclusions: IF-IMRT combined with S-1 is a promising regimen for elderly ESCC. And the radiotherapy dose of 50.4 Gy remains the standard dose for EPs with ESCC undergoing CCRT.

Objective: To identify variables associated with a patients' ability to reproducibly hold their breath for deep-inspiration breath-hold (DIBH) radiotherapy (RT) and to develop a predictive model for DIBH eligibility.

Methods: This prospective, single-institution, IRB-approved observational study included women with left-sided breast cancer treated between January 2023 and March 2024. Patients underwent multiple breath-hold sessions over 2-3 consecutive days. DIBH waveform metrics and clinical factors were recorded and analysed. Logistic mixed modelling was used to predict DIBH eligibility, and a temporal validation cohort was used to assess model performance.

Results: In total, 253 patients were included, with 206 in the model development cohort and 47 in the temporal validation cohort. The final logistic mixed model identified increasing average breath-hold duration (OR, 95% CI: 0.308, 0.104-0.910. p = 0.033) and lower amplitude (OR, 95% CI: 0.737, 0.641-0.848. p < 0.001) as significant predictors of DIBH eligibility. Increasing age was associated with higher odds of being ineligible for DIBH (OR, 95% CI: 1.040, 1.001-1.081. p = 0.044). The model demonstrated good discriminative performance in the validation cohort with an AUC of 80.9% (95% CI: 73.0-88.8).

Conclusion: The identification of variables associated with DIBH eligibility and development of a predictive model has the potential to serve as a decision-support tool. Further external validation is required before its integration into routine clinical practice.

Purpose/objective: Currently, there are few prospective data on the tolerability of combining targeted therapies (TT) with radiation therapy (RT). The objective of this prospective study was to assess the feasibility and toxicity of pairing RT with concurrent TT in cancer patients. The aim was to enhance the existing evidence base for the simultaneous administration of targeted substances together with radiotherapy.

Methods: Prospective study enrollment was conducted at a single institution between March 1, 2020, and December 31, 2021, for all patients diagnosed with histologically confirmed cancer who underwent external beam radiotherapy in combination with targeted therapy. The study, known as the "targeted RT study," was registered in the German Clinical Trials Register under DRKS00026193. Systematic documentation of the toxicity profiles of different targeted therapies was performed, and the assessment of acute toxicity followed the guidelines of the National Cancer Institute Common Terminology Criteria for Adverse Events Version v5.0.

Results: A total of 334 patients underwent 683 radiation therapy series. During the course of RT, 51 different TT substances were concurrently administered. External beam radiotherapy was employed for various anatomical sites. The combination of RT and concurrent TT administration was generally well tolerated, with no instances of severe acute toxicity observed. The most commonly reported toxicity was fatigue, ranging from mild to moderate Common Terminology Criteria for Adverse Events (CTCAE) °I-°III. Other frequently observed toxicities included dermatitis, dyspnea, dysphagia, and dry cough. No toxicity greater than moderate severity was recorded at any point. In only 32 patients (4.7% of evaluated RT series), the concurrent substance administration was discontinued due to side effects. However, these side effects did not exceed mild severity according to CTCAE, suggesting that discontinuation was a precautionary measure. Only one patient receiving Imatinib treatment experienced a severe CTCAE °III side effect, leading to discontinuation of the concurrent substance due to the sudden occurrence of melaena during RT.

Conclusion: In conclusion, the current study did not demonstrate a significant increase or additional toxicity when combining radiotherapy and concurrent targeted therapy. However, additional research is required to explore the specific toxicity profiles of the various substances that can be utilized in this context.

Trial registration number: DRKS00026193. Date of registration 12/27/2022 (retrospectively registered).

Background: Local therapies may benefit patients with oligometastatic cancer. However, there were limited data about pancreatic cancer. Here, we compared the efficacy and safety of stereotactic body radiation therapy (SBRT) to the primary tumor and all oligometastases with SBRT to the primary tumor alone in patients with metastatic pancreatic cancer.

Methods: A retrospective review of patients with synchronous oligometastatic pancreatic cancer (up to 5 lesions) receiving SBRT to all lesions (including all oligometastases and the primary tumor) were performed. Another comparable group of patients with similar baseline characteristics, including metastatic burden, SBRT doses, and chemotherapy regimens, receiving SBRT to the primary tumor alone were identified. The primary endpoint was overall survival (OS). The secondary endpoints were progression frees survival (PFS), polyprogression free survival (PPFS) and adverse events.

Results: There were 59 and 158 patients receiving SBRT to all lesions and to the primary tumor alone. The median OS of patients with SBRT to all lesions and the primary tumor alone was 10.9 months (95% CI 10.2-11.6 months) and 9.3 months (95% CI 8.8-9.8 months) (P < 0.001). The median PFS of two groups was 6.5 months (95% CI 5.6-7.4 months) and 4.1 months (95% CI 3.8-4.4 months) (P < 0.001). The median PPFS of two groups was 9.8 months (95% CI 8.9-10.7 months) and 7.8 months (95% CI 7.2-8.4 months) (P < 0.001). Additionally, 14 (23.7%) and 32 (20.2%) patients in two groups had grade 3 or 4 treatment-related toxicity.

Conclusions: SBRT to all oligometastases and the primary tumor in patients with pancreatic cancer may improve survival, which needs prospective verification.

Background and purpose: Cone beam computed tomography (CBCT) is routinely used in radiotherapy to localize target volume. The aim of our study was to determine the biological effects of CBCT dose compared to subsequent therapeutic dose by using in vitro chromosome dosimetry.

Materials and methods: Peripheral blood samples from five healthy volunteers were irradiated in two phantoms (water filled in-house made cylindrical, and Pure Image CTDI phantoms) with 6 MV FFF X-ray photons, the dose rate was 800 MU/min and the absorbed doses ranged from 0.5 to 8 Gy. Irradiation was performed with a 6 MV linear accelerator (LINAC) to generate a dose-response calibration curve. In the first part of the investigation, 1-5 CBCT imaging was used, in the second, only 2 Gy doses were delivered with a LINAC, and then, in the third part, a combination of CBCT and 2 Gy irradiation was performed mimicking online adapted radiotherapy treatment. Metaphases were prepared from lymphocyte cultures, using standard cytogenetic techniques, and chromosomal aberrations were evaluated. Estimate doses were calculated from chromosome aberrations using dose-response curves.

Results: Samples exposed to X-ray from CBCT imaging prior to treatment exhibited higher chromosomal aberrations and Estimate dose than the 2 Gy therapeutic (real) dose, and the magnitude of the increase depended on the number of CBCTs: 1-5 CBCT corresponded to 0.04-0.92 Gy, 1 CBCT + 2 Gy to 2.32 Gy, and 5 CBCTs + 2 Gy to 3.5 Gy.

Conclusion: The estimated dose based on chromosomal aberrations is 24.8% higher than the physical dose, for the combination of 3 CBCTs and the therapeutic 2 Gy dose, which should be taken into account when calculating the total therapeutic dose that could increase the risk of a second cancer. The clinical implications of the combined radiation effect may require further investigation.

Purpose: To explore the influence of circulating lymphocyte subsets, serum markers, clinical factors, and their impact on overall survival (OS) in locally advanced nasopharyngeal carcinoma (LA-NPC). Additionally, to construct a nomogram predicting OS for LA-NPC patients using independent prognostic factors.

Methods: A total of 530 patients with LA-NPC were included in this study. In the training cohort, Cox regression analysis was utilized to identify independent prognostic factors, which were then integrated into the nomogram. The concordance index (C-index) was calculated for both training and validation cohorts. Schoenfeld residual analysis, calibration curves, and decision curve analysis (DCA) were employed to evaluate the nomogram. Kaplan-Meier methods was performed based on risk stratification using the nomogram.

Results: A total of 530 LA-NPC patients were included. Multivariate Cox regression analysis revealed that the circulating CD8⁺T cell, platelet-to-lymphocyte ratio (PLR), lactate dehydrogenase (LDH), albumin (ALB), gender, and clinical stage were independent prognostic factors for LA-NPC (p < 0.05). Schoenfeld residual analysis indicated overall satisfaction of the proportional hazards assumption for the Cox regression model. The C-index of the nomogram was 0.724 (95% CI: 0.669-0.779) for the training cohort and 0.718 (95% CI: 0.636-0.800) for the validation cohort. Calibration curves demonstrated good correlation between the model and actual survival outcomes. DCA confirmed the clinical utility enhancement of the nomogram over the TNM staging system. Significant differences were observed in OS among different risk stratifications.

Conclusion: Circulating CD8⁺ T cell, PLR, LDH, ALB, gender and clinical stage are independent prognostic factors for LA-NPC. The nomogram and risk stratification constructed in this study effectively predict OS in LA-NPC.

Radiation therapy (RT) continues to be the primary approach for treating cancer, and numerous cancer biomarkers associated with oncological outcomes have been investigated in the context of RT. The serum platelet-to-lymphocyte ratio (PLR) is one of the emerging landmark biomarker in the oncologic field. Mounting evidence indicates that an elevated serum PLR may function as a marker of unfavorable tumor characteristics, adverse treatment outcomes and treatment-related toxicities among individuals undergoing RT. However, the findings of these investigations have revealed a few disparities among researchers, highlighting the need for further meticulously planned studies to draw conclusive results. This article provides a comprehensive literature review and in-depth discussion regarding the clinical implications of the serum PLR in the modern RT era.

Purpose: Convolutional Neural Networks (CNNs) have emerged as transformative tools in the field of radiation oncology, significantly advancing the precision of contouring practices. However, the adaptability of these algorithms across diverse scanners, institutions, and imaging protocols remains a considerable obstacle. This study aims to investigate the effects of incorporating institution-specific datasets into the training regimen of CNNs to assess their generalization ability in real-world clinical environments. Focusing on a data-centric analysis, the influence of varying multi- and single center training approaches on algorithm performance is conducted.

Methods: nnU-Net is trained using a dataset comprising 161 ¹⁸F-PSMA-1007 PET images collected from four distinct institutions (Freiburg: n = 96, Munich: n = 19, Cyprus: n = 32, Dresden: n = 14). The dataset is partitioned such that data from each center are systematically excluded from training and used solely for testing to assess the model's generalizability and adaptability to data from unfamiliar sources. Performance is compared through a 5-Fold Cross-Validation, providing a detailed comparison between models trained on datasets from single centers to those trained on aggregated multi-center datasets. Dice Similarity Score, Hausdorff distance and volumetric analysis are used as primary evaluation metrics.

Results: The mixed training approach yielded a median DSC of 0.76 (IQR: 0.64-0.84) in a five-fold cross-validation, showing no significant differences (p = 0.18) compared to models trained with data exclusion from each center, which performed with a median DSC of 0.74 (IQR: 0.56-0.86). Significant performance improvements regarding multi-center training were observed for the Dresden cohort (multi-center median DSC 0.71, IQR: 0.58-0.80 vs. single-center 0.68, IQR: 0.50-0.80, p < 0.001) and Cyprus cohort (multi-center 0.74, IQR: 0.62-0.83 vs. single-center 0.72, IQR: 0.54-0.82, p < 0.01). While Munich and Freiburg also showed performance improvements with multi-center training, results showed no statistical significance (Munich: multi-center DSC 0.74, IQR: 0.60-0.80 vs. single-center 0.72, IQR: 0.59-0.82, p > 0.05; Freiburg: multi-center 0.78, IQR: 0.53-0.87 vs. single-center 0.71, IQR: 0.53-0.83, p = 0.23).

Conclusion: CNNs trained for auto contouring intraprostatic GTV in ¹⁸F-PSMA-1007 PET on a diverse dataset from multiple centers mostly generalize well to unseen data from other centers. Training on a multicentric dataset can improve performance compared to training exclusively with a single-center dataset regarding intraprostatic ¹⁸F-PSMA-1007 PET GTV segmentation. The segmentation performance of the same CNN can vary depending on the dataset employed for training and testing.