Radiation Oncology最新文献

Background: To evaluate treatment outcomes, toxicity, and recurrence patterns by dose level in nasopharyngeal carcinoma (NPC) patients treated with intensity-modulated radiotherapy (IMRT) and weekly cisplatin.

Methods: We retrospectively analyzed 48 NPC patients treated between 2005 and 2019 with IMRT and weekly cisplatin (40 mg/m²). The planning target volume (PTV) received a median total dose of 57.6 Gy (1.8 Gy/fraction) with a simultaneous integrated boost to the primary tumor and nodal metastases up to 70.4 Gy. To assess recurrence patterns, follow-up imaging was deformably co-registered with planning CTs (pCT), and recurrent gross tumor volumes (rGTVs) were delineated and mapped to pCTs. Recurrences were categorized using a centroid-based system into five types: A (central high-dose), B (peripheral high-dose), C (central intermediate-/low-dose), D (peripheral intermediate-/low-dose), and E (extraneous dose).

Results: With a median follow-up of 73 months (range 24-156), 9 patients (19%) had died. The 3-, 5-, and 10-year overall survival rates were 98%, 96%, and 67%, respectively. Local control rates (LCR) at 2, 3, and 5 years were 92%, 89%, and 89%; regional control was 96%, 94%, and 94%; and distant control was 92%, 89%, and 89%. Treatment was well tolerated, with no grade ≥ 4 toxicities. Grade 3 acute toxicities occurred in 23 patients (48%), most commonly dysphagia, with nearly all resolving within 90 days. Among treatment failures, distant metastases (13%) and local relapses (10%) were most frequent. Of 8 local and/or regional recurrences analyzed, 2 were type A (central high-dose), 3 type B ("marginal"), 2 type C (central intermediate-/low-dose), and 1 type E ("out-of-field").

Conclusion: IMRT with weekly cisplatin yields excellent survival and locoregional control with acceptable toxicity in NPC. Distant metastasis as one of the predominant failure patterns highlights the need for more effective systemic therapies. Most local recurrences arose within high-dose areas, suggesting a potential opportunity for treatment optimization.

Background: To address the issue where single Volumetric Modulated Arc Therapy (VMAT) delivery times often exceed a patient's comfortable breath-hold capacity of approximately 20s during Deep Inspiration Breath-Hold (DIBH) radiotherapy for breast cancer, this study proposes and systematically evaluates a novel time-control optimization strategy. The goal is to reduce overall delivery time and improve temporal uniformity across individual arcs within the United Imaging Healthcare (UIH) uTPS platform.

Methods: The study included 32 left-sided breast cancer patients, with 16 having undergone breast-conserving surgery and 16 having undergone mastectomy. For each patient, 16 distinct VMAT plans were generated to compare combinations of optimization algorithms (FMO/SPO), fluence modes (FF/FFF), and various dose rates. A novel bounding factor analysis was introduced to quantify delivery bottlenecks by assessing the relative contributions of gantry rotation, MLC movement, and MU delivery to the overall treatment time.

Results: The time-control strategy effectively reduced the mean arc delivery time and improved its uniformity across all tested combinations. The bounding factor analysis revealed that FMO plans were primarily limited by Multi-Leaf Collimator (MLC) movement, whereas SPO plans were predominantly limited by Monitor Unit (MU) delivery. Consequently, when the time-control strategy was applied to FMO plans, it shortened delivery times by restricting MLC mobility, which led to some dosimetric degradation. In contrast, for SPO plans, the strategy maintained or enhanced MLC movement while significantly reducing time, thus preserving or even improving dosimetric quality. Notably, the combination of SPO with the high-dose-rate (1400 MU/min) FFF mode reduced single-arc delivery times to approximately 10s.

Conclusions: The proposed time-control strategy is a superior solution for shortening delivery time and enhancing patient comfort without significant dosimetric compromise.

Objective: Immune checkpoint inhibitors plus thoracic radiotherapy (RT) may magnify the radiation pneumonitis (RP) risk. Data on the risk for symptomatic RP in small cell lung cancer (SCLC) patients following RT after induction immunochemotherapy using anti-programmed cell death protein-1 monoclonal antibody Serplulimab, cisplatin plus etoposide are limited.

Methods: This retrospective study included 443 SCLC patients from two hospitals who finished thoracic intensity-modulated radiation therapy or volumetric modulated arc therapy between April 1, 2022 and March 31, 2025. The primary endpoint was the incidence of grade 2 or worse (grade 2+) RP. Fine-Gray competing risks regression analyses were used to identify the potential risk factors of RP2+.

Results: The follow-up duration was (15.8 ± 4.6) weeks since the end of RT. In detail, 87 (19.6%), 35 (7.9%), and 6 (1.4%) patients developed grade 2, grade 3, and grade 4 RP respectively. Six patients died from non-RP-related diseases were treated as competing events. On univariate analysis, male, pneumoconiosis, ECOG status, concurrent chemoradiotherapy (CCRT) were positively correlated with the incidence of RP2+, with subdistribution hazard ratio (SHR) and 95% confidence interval (CI) of 1.81 (1.29-2.55), 2.56 (1.35-4.87), 1.53 (1.17-1.99) and 2.15 (1.35-3.42), respectively (all P < 0.05), while VO_2max, left ventricular ejection fraction (LVEF), and forced expiratory volume in one second (FEV₁) were negatively correlated with RP2+, with SHR and 95%CI of 0.89 (0.84-0.935), 0.98 (0.96-1.00), and 0.34 (0.19-0.61), respectively (all P < 0.05). Further multivariate competing risks analysis revealed that male, CCRT, and VO2max were independent predictors of RP2+, with SHR and 95% as 1.84 (1.22-2.78), 1.72 (1.04-2.87), and 0.92 (0.86-0.98), respectively (all P < 0.05). Additionally, immunochemotherapy before RT, preexisting pulmonary co-morbidities and smoking history were not significant indicators of RP2+ (P > 0.05, respectively).

Conclusion: The incidence of RP2 + following sequential immunochemotherapy and RT was positively associated with male and CCRT, but negatively correlated with VO₂ max in SCLC patients.

Clinical trial number: Not applicable.

Aim: To evaluate sex-based differences in survival outcomes, toxicity, and patterns of local recurrence in patients with locally advanced head and neck squamous cell carcinoma (HNSCC) treated with definitive or adjuvant radiotherapy (RT).

Methods: We conducted a retrospective review of 309 patients (246 males, 63 females) diagnosed with primary squamous cell carcinoma of the oropharynx, larynx, or hypopharynx treated with curative-intent RT at our institution between 2016 and 2023. Inclusion criteria comprised histologically confirmed SCC, stage T3/T4 and/or node-positive disease, and complete RT treatment with adequate follow-up. Survival endpoints-overall survival (OS), progression-free survival (PFS), and metastasis-free survival (MFS)-were analyzed using the Kaplan-Meier method and log-rank tests. Patterns of local failure were classified using an established five-type system: A (central high-dose), B (peripheral high-dose), C (central intermediate- or low-dose), D (peripheral intermediate- or low-dose), and E (extraneous dose). Treatment-related toxicity was also compared between sexes.

Results: No significant differences in OS, PFS, or MFS were found between male and female patients across all treatment subgroups. Log rank test did not identify any significant prognostic factor for survival and local recurrence. However, female patients experienced a higher rate of grade ≥ 3 dermatitis (12.7% vs. 5.3%, p = 0.037). Pattern A nodal failures (central high-dose volume) were significantly more common in females (64.3%) than in males (28.8%; p = 0.014), while other recurrence patterns showed no significant sex-based differences.

Conclusion: Sex was not an independent predictor of survival in this cohort of locally advanced HNSCC patients. Nevertheless, the higher rate of severe skin toxicity and nodal failures in females highlights a potential need for sex-adapted radiotherapy strategies and further prospective investigation.

Clinical trial number: Not applicable.

Background: Radiotherapy is considered as a second or third-line treatment for recurrent pituitary adenomas. As it is a benign tumor, the balance should clearly favor the benefit and induce the least amount of side effects.

Purpose: This retrospective study aims to evaluate the incidence of side effects after treatment and their actual causality with radiotherapy through dosimetric analysis.

Methods: A cohort of 35 patients who underwent normofractionated radiation therapy following unsuccessful surgical or medical interventions was identified. 48.6% (17/35) had functioning adenomas (29.41% adrenocorticotrophic hormone-secreting, 35.3% growth hormone-secreting, and 23.5% prolactin-secreting adenomas). Surgery was previously employed in 94.29% of patients. A median dose of 54 Gy was prescribed in the planning target volume (PTV) in a normofractionated schedule. Patients were clinically monitored by endocrinologists, ophthalmologists, and radiation oncologists, and patients underwent MRI and hormonal analyses frequently.

Results: The median follow-up time was 54.94 months. None of the patients experienced acute side effects of grade 3 or higher. Regarding late side effects, new-onset hypopituitarism was observed in 14.3% of patients, with all patients exceeding the dose constraint to pituitary gland. Additionally, 25.7% reported subjective memory loss complaints, 4 underwent a neuropsychological assessment, and only 2 were confirmed. Furthermore, 8 out of 9 patients did not adhere to the maximum dose constraints for the hippocampus. Subjective auditory impairment was experienced by 31.3% of patients, with 4 out of 11 undergoing ENT evaluation, and 1 out of 4 describing radio-induced tubal catharsis. All 11 patients adhered to the cochlear constraints. Five cases of cataracts were reported, with all patients adhering to lens constraints, although they were significantly older than those without cataracts. Two cases of temporary cranial nerve deficits, one visual impairment, one epilepsy, and one transient ischemic attack were also documented.

Background: Carbon-ion radiotherapy (CIRT) for head and neck tumors is typically delivered in the supine posture using fixed beam lines, which limits beam angle selection. Combining upright posture with fixed beam lines offers expanded angular access and potential dosimetric advantages, yet optimal angle configurations remain unclear. This study identifies optimal beam angles in head and neck CIRT by comparing dosimetry and robustness of upright and supine plans for fixed-beam systems, thereby supporting beam angle optimization and clinical implementation of upright treatment in fixed-beam systems.

Methods: Twenty patients with head and neck cancer were retrospectively robustly optimized using four beam configurations: horizontal beams at 0° (S0) and with a 15° superior-oblique tilt (S15) in the supine posture, anterior beams at 15° (U15) and 45° (U45) in the upright posture. Plans were generated in RayStation (v10B) accounting for ± 3 mm setup and ± 3.5% range uncertainties. Target coverage (D_95%, D_2%, V_95%, conformity index [CI], homogeneity index [HI]), plan robustness (DVH bands, worst-case scenario), and organ-at-risk (OAR) dosimetry (mean dose to cochleae and parotid glands, and brainstem D_1cc) were compared. Statistical analyses used paired t-tests or Wilcoxon signed-rank tests.

Results: All plans achieved comparable nominal target coverage and similar CI values. S15 showed significantly improved robustness (DVH band ΔD_95% = 0.5 Gy(RBE), ΔV_95% = 1.4%; worst-case ΔD_95% = 0.3 Gy(RBE), ΔHI = 0.01, ΔCI = 0.02, all p < 0.05) and lower OAR doses versus S0 (cochlea: 28.4 vs. 30.6 Gy(RBE), parotid: 13.5 vs. 18.5 Gy(RBE), brainstem D_1cc: 40.1 vs. 41.7 Gy(RBE), all p < 0.001). U15 exhibited comparable robustness to S15 with further reductions in cochlea (18.5 vs. 28.4 Gy(RBE), p < 0.001) and parotid sparing (11.9 vs. 13.5 Gy(RBE), p < 0.05). U45 showed the highest robustness and OAR sparing, except for the brainstem, where D_1cc was significantly increased (50.9 Gy(RBE), p < 0.05).

Conclusions: The anterior beams at 15°in the upright setup (U15) showed the best balance of robustness and OAR sparing, making it the preferred option. The 15°-angled supine setup (S15) is a practical alternative. S0 and U45 are not recommended due to inferior robustness and higher brainstem dose, respectively.

Background: Tumor heterogeneity is a significant factor contributing to the marked differences in survival rates among glioblastoma multiforme (GBM) patients, who face a poor prognosis. To improve personalized treatment, it is essential to identify specific tumor characteristics that capture this variability and aid in predicting survival. This study aimed to evaluate the utility of dosiomics and radiomics in predicting overall survival (OS). The central hypothesis was that integrating dosiomics and radiomics could improve survival outcome predictions.

Methods: A total of 74 GBM patients from The Cancer Imaging Archive were retrospectively included. Dosiomic features from the gross tumor volume (GTV) of planned dose distributions, along with radiomic features from the contrast-enhanced tumor (CET) and edema/non-contrast-enhanced tumor (ED/nCET) subregions across various pre-radiation MRI modalities, were extracted and optimized using L1-based feature selection. Logistic Regression (LR) models were built utilizing different feature configurations to assess the discriminative power of dosiomic and radiomic features, considering the impact of heterogeneous subregions. Model performance was assessed through stratified 10-fold cross-validation (CV).

Results: The dosiomic model exhibited a mean area under the receiver operating characteristic (ROC) curve (AUC) of 0.80 ± 0.12. The subregion-based models demonstrated mean AUC values of 0.90 ± 0.09 for the CET subregion and 0.76 ± 0.10 for the ED/nCET subregion, indicating that the CET subregion significantly outperformed the ED/nCET subregion (p-value < 0.05). The mean AUC values for modality-based models were as follows: 0.86 ± 0.12 for T1-weighted contrast-enhanced (T1CE), 0.84 ± 0.18 for T1-weighted (T1), 0.85 ± 0.14 for T2-weighted (T2), and 0.76 ± 0.21 for fluid-attenuated inversion recovery (FLAIR) sequences. There was no significant difference in discrimination power among the four modalities (p-value > 0.05). The combined dosiomic and CET model improved performance to 0.96 ± 0.07 (p < 0.05).

Conclusions: Dosiomic and pre-radiotherapy MRI-derived radiomic features are capable of stratifying GBM patients into two long-term and short-term groups. Notably, the integration of dosiomics and radiomics significantly enhances survival prediction in GBM patients.