BACKGROUND: Part of the current stereotactic arrythmia radioablation (STAR) workflow is transfer of findings from the electroanatomic mapping (EAM) to computed tomography (CT). Here, we analyzed inter- and intraobserver variation in a modified EAM-CT registration using automatic registration algorithms designed to yield higher robustness. MATERIALS AND METHODS: This work is based on data of 10 patients who had previously undergone STAR. Two observers participated in this study: (1) an electrophysiologist technician (cardiology) with substatial experience in EAM-CT merge, and (2) a clinical engineer (radiotherapy) with minimum experience with EAM-CT merge. EAM-CT merge consists of 3 main steps: segmentation of left ventricle from CT (CT LV), registration of the CT LV and EAM, clinical target volume (CTV) delineation from EAM specific points. Mean Hausdorff distance (MHD), Dice Similarity Coefficient (DSC) and absolute difference in Center of Gravity (CoG) were used to assess intra/interobserver variability. RESULTS: Intraobserver variability: The mean DSC and MHD for 3 CT LVs altogether was 0.92 ± 0.01 and 1.49 ± 0.23 mm. The mean DSC and MHD for 3 CTVs altogether was 0,82 ± 0,06 and 0,71 ± 0,22 mm. Interobserver variability: Segmented CT LVs showed great similarity (mean DSC of 0,91 ± 0,01, MHD of 1,86 ± 0,47 mm). The mean DSC comparing CTVs from both observers was 0,81 ± 0,11 and MHD was 0,87 ± 0,45 mm. CONCLUSIONS: The high interobserver similarity of segmented LVs and delineated CTVs confirmed the robustness of the proposed method. Even an inexperienced user can perform a precise EAM-CT merge following workflow instructions.
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- časopisecké články MeSH
BACKGROUND: The optimal radiotherapy technique for cardiac sparing in left-sided early breast cancer (EBC) is not clear. In this context, the aim of our dosimetric study was to compare cardiac and lung doses according to the type of radiotherapy - whole breast irradiation (WBI), external partial breast irradiation (PBI), and multicatheter interstitial brachytherapy-accelerated partial breast irradiation (MIB-APBI). The dosimetric results with the WBI and PBI were calculated with and without DIBH. MATERIALS AND METHODS: Dosimetric study of 23 patients treated with WBI, PBI, with and without DIBH, or MIB-APBI. The prescribed dose was 40 Gy in 15 fractions for WBI and PBI and 34 Gy in 10 fractions (bid) for MIB-APBI. Doses to the organs-at-risk (OAR) - heart, left anterior descending coronary artery (LAD), left ventricle (LV), and left lung - were recalculated to the equivalent dose in 2-Gy fractions (EQD2). RESULTS: The addition of DIBH significantly reduced EQD2 doses to all OARs (except for the left lung maximal dose) in WBI and PBI. MHD values were 0.72 Gy for DIBH-WBI, 1.01 Gy for MIB-APBI and 0.24 Gy for DIBH-PBI. There were no significant differences in cardiac doses between WBI with DIBH and PBI without DIBH. DIBH-PBI resulted in significantly lower mean doses to all OARs (except for maximum lung dose) compared to MIB-APBI. Conclusions: These results show that the use of DIBH significantly reduces cardiac doses in patients with left EBC. Partial irradiation techniques (PBI, MIB-APBI) significantly reduced cardiac doses due to the smaller clinical target volume. The best results were obtained with DIBH-PBI.
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- časopisecké články MeSH
BACKGROUND: The aim was to assess therapeutic outcomes and tolerance in patients with metastatic castration resistant prostate cancer (mCRPC) treated with androgen receptor targeted agents (ARTA) treatment at one oncological center in the Czech Republic. MATERIALS AND METHODS: Retrospective analysis of 64 patients with mCRPC treated with abiraterone (50 patients) and enzalutamide (14 patients) in the first line of this disease was conducted. Kaplan-Meier analysis was used to calculate progression free survival (PFS) and overall survival (OS). We performed a multivariate analysis of risk factors for treatment outcomes (PFS, OS) by Cox regression analysis. RESULTS: The median follow-up was 28.4 months. The median PFS was 15.4 months [95% confidence interval (CI): 12.3-18.5], median OS was 38.2 months (95% CI: 19.9-56.5). Regression analysis demonstrated a favorable prognostic effect on PFS in patients with reduction of PSA ≥ 50 %, in patients with early reduction of prostate-specific antigen (PSA) ≥ 50% within 3 months, in patients younger than 74 years and in overall performance status (PS) 0. Regression analysis demonstrated a favorable prognostic effect on OS in patients with reduction of PSA ≥ 50 %, in patients with early reduction of PSA ≥ 50 % within 3 months and in patients with overall PS 0. Adverse effects grade 3-4 were reported in 17 (27.9%) patients in abirateron arm and in 1 (7.1%) patient in enzalutamide arm. CONCLUSION: The analysis of patients with mCRPC treated with ARTA in the first line showed that ARTA represents an effective and safe therapy and contributes to longer survival.
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BACKGROUND: The aim of this retrospective study is to analyze a consecutive cohort of brain metastasis (BM) patients treated off clinical trials through combination of surgery and radiotherapy over the last 15 years in a tertiary neurooncology center. MATERIALS AND METHODS: All BM patients operated between 2007-2019 received adjuvant linac-based radiotherapy categorized to whole brain radiotherapy (WBRT) and tumor bed stereotactic radiotherapy. Survival outcomes and local control was analyzed. RESULTS: In total, 118 patients were enrolled, those with stereotactic radiotherapy (41%) had better baseline characteristics mirrored in longer overall survival (OS) [18 vs. 7.1 months, p < 0.001; hazard ratio (HR) 0.47, p = 0.004] with median follow-up of 58 months. Cumulative incidence for local, distant, and extracranial control was not significantly different between groups, with 12-month cumulative control of 22% vs. 18%, 44% vs. 29%, and 35% vs. 32% for stereotactic and WBRT group, respectively. WBRT was an independent factor for better distal brain control. CONCLUSIONS: Real world data demonstrating significantly better overall survival in patients treated with postoperative targeted radiotherapy compared with postoperative WBRT is presented, with no significant difference in cumulative incidence for local or distant brain control. The majority of patients with targeted radiotherapy had a fractionated dose schedule with outcomes comparable to single-dose radiation trials of postoperative targeted radiotherapy.
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- časopisecké články MeSH
Prophylactic cranial irradiation (PCI) is considered an important technological advance made in oncology in an effort to reduce the incidence of brain metastases (BM) and improve overall survival (OS) of patients with small cell lung cancer (SCLC). Although it is often reported that PCI improves the therapeutic potential in limited-stage (LS) SCLC, no randomised trial has ever conclusively confirmed this. Nevertheless, PCI has been considered the standard of care for LS-SCLC since the late 1990s. The data supporting the use of PCI in LS-SCLC are based on an analysis of work performed prior to the current approach to staging [brain magnetic resonance imaging (MRI), positron emission tomography (PET)/computed tomography (CT)]. The evidence for the rationale and feasibility of this approach in the modern diagnostic era should be demonstrated. The situation with extensive stage (ES) SCLC is seemingly easier because, unlike LS-SCLC, we have data from two randomised trials. Unfortunately, their results are in direct conflict with each other. Although it is generally assumed that good control of brain disease leads to better quality of life, this has never been prospectively demonstrated. In fact, PCI is associated not only with increased treatment costs and some patient discomfort, but also with non-negligible potential toxicity. For this reason, efforts have been made to preserve cognitive function by sparing the hippocampus. This concept is called hippocampal avoidance. The optimal fractionation regimen is currently less controversial than the optimal integration of PCI into the treatment algorithm. A dose of 25 Gy administered in 10 fractions should remain the standard for the eventual use of PCI in patients with SCLC. In summary, PCI is not a conditio sine qua non in any indication. Neither in patients with LS-SCLC nor in patients with ES-SCLC has a clear improvement in OS been demonstrated at follow-up using current imaging modalities.
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- přehledy MeSH
BACKGROUND: The objective was to evaluate the efficacy and toxicity of curative radiotherapy in patients with sinonasal carcinoma and to identify prognostic factors influencing treatment outcomes. MATERIALS AND METHODS: The authors conducted a retrospective study of 61 consecutive patients treated with postoperative or definitive radiotherapy from 2002 to 2018 (median age 59 years, current/former smokers 71%, maxillary sinus 67%, nasal cavity 26%). The majority of patients were diagnosed with locally advanced disease (85% clinical stage ≥ III). Regional cervical metastases were initially diagnosed in 23% of patients. The most common histology was squamous cell carcinoma (61%). Radiation therapy was preceded by radical surgery in 64% of patients. 29 patients received chemotherapy (48%). RESULTS: The median follow-up was 53 months. The median total dose of radiotherapy achieved was 70 Gy. The 5- and 10-year locoregional control, distant control, overall survival, and disease-free survival were 74% and 64%, 90% and 90%, 51% and 35%, and 38% and 25%, respectively. Severe acute toxicity occurred in 36%, severe late toxicity in 23% of patients. Severe unilateral visual impairment occurred in 6 patients, temporal lobe necrosis in 1 patient, and osteoradionecrosis requiring surgery in 2 patients. CONCLUSION: The results of the study demonstrated the high effectiveness of curative treatment in patients with sinonasal carcinoma with long-term locoregional and distant control. The multivariate analysis indicated that N-staging, age, comorbidity score [as assessed by Adult Comorbidity Evaluation 27 (ACE-27)] and initial response to treatment were the strongest prognostic factors.
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BACKGROUND/OBJECTIVE: Hormone receptor (HR) status is one of the key factors in determining the treatment of breast cancer. Previous studies suggested that HR status may change in metastatic tissue. However, available studies focused mainly on primary biopsies and there are only few trials comparing HR status in the primary tumour and the metastasis using material from complete resection. The aim of the study was to determine the frequency of HR alterations in metastatic breast cancer. MATERIALS AND METHODS: The study retrospectively examines a total of 50 patients who underwent brain, lung, or liver metastasectomy for metastatic breast cancer between January 2000 and January 2019. RESULTS: HR conversion was observed in a total of 30 cases (60.0%), while HER-2/neu (human epidermal growth factor receptor 2) discrepancy surprisingly occurred only in one case (2.0%). A change in immunophenotype occurred in 28% of cases. Triple-negativity was more frequent in brain metastases (p = 0.039). CONCLUSIONS: We have confirmed that HR conversion between the primary tumour and its metastases occurs in a significant number of cases, which has important implications for further treatment decisions.
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BACKGROUND: The purpose of this work is to improve a sweeping beam technique for total body irradiation (TBI) on a low flat couch using a varying patient thickness model. We designed a flat couch for total body irradiation in supine and prone position. Three generic arcs with rectangular segments for a patient torso thickness of 16, 22 and 28 cm were generated with respect to varying patient thickness of four particular parts of the body: head, torso, thighs and calves. MATERIALS AND METHODS: Longitudinal and transversal dose profiles were measured using an ionization chamber and the EBT3 gafchromic film in a solid water slab phantom. The robustness of the method was examined in phantoms of different thicknesses. RESULTS: Measured dose homogeneity stays within ±10% of prescribed dose for all of the three patient thickness models. The robustness of the method was evaluated as the increase in dose in the phantom center of 0.7% per 1 cm reduction in phantom thickness. CONCLUSION: The method is applicable for the broad range of patient sizes, comfortable for patients, robust and suitable for standard treatment rooms with a standard linear accelerator. It requires minimal investments into equipment.
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- časopisecké články MeSH
Background: This retrospective analysis evaluated the long-term outcome of spinal stereotactic body radiotherapy (SBRT) treatment for hemangioblastomas. Materials and methods: Between 2010 and 2018, 5 patients with 18 Von-Hippel Lindau-related pial-based spinal hemangioblastomas were treated with fractionated SBRT. After precisely registering images of all relevant datasets, we delineated the gross tumor volume, spinal cord (including intramedullary cysts and/or syrinxes), and past radiotherapy regions. A sequential optimization algorithm was used for dose determinations, and patients received 25-26 Gy in five fractions or 24 Gy in three fractions. On-line image guidance, based on spinal bone structures, and two orthogonal radiographs were provided. The actuarial nidus control, surgery-free survival, cyst/syrinx changes, and progression-free survival were calculated with the Kaplan-Meier method. Toxicities were graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events v5.0. Results: The median follow-up was 5 years after SBRT. Patients displayed one nidus progression, one need of neurosurgery, and two cyst/syrinx progressions directly connected to symptom worsening. No SBRT-related complications or acute adverse radiation-related events occurred. However, one asymptomatic radiological sign of myelopathy occurred two years after SBRT. All tumors regressed; the one-year equivalent tumor volume reduction was 0.2 mL and the median volume significantly decreased by 28% (p = 0.012). Tumor volume reductions were not correlated with the mean (p = 0.19) or maximum (p = 0.16) dose. Conclusions: SBRT for pial-based spinal hemangioblastomas was an effective, safe, viable alternative to neurosurgery in asymptomatic patients. Escalating doses above the conventional dose-volume limits of spinal cord tolerance showed no additional benefit.
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Background: Here we aimed to evaluate the respiratory and cardiac-induced motion of a ICD lead used as surrogate in the heart during stereotactic body radiotherapy (SBRT) of ventricular tachycardia (VT). Data provides insight regarding motion and motion variations during treatment. Materials and methods: We analyzed the log files of surrogate motion during SBRT of ventricular tachycardia performed in 20 patients. Evaluated parameters included the ICD lead motion amplitudes; intrafraction amplitude variability; correlation error between the ICD lead and external markers; and margin expansion in the superior-inferior (SI), latero-lateral (LL), and anterior-posterior (AP) directions to cover 90% or 95% of all amplitudes. Results: In the SI, LL, and AP directions, respectively, the mean motion amplitudes were 5.0 ± 2.6, 3.4. ± 1.9, and 3.1 ± 1.6 mm. The mean intrafraction amplitude variability was 2.6 ± 0.9, 1.9 ± 1.3, and 1.6 ± 0.8 mm in the SI, LL, and AP directions, respectively. The margins required to cover 95% of ICD lead motion amplitudes were 9.5, 6.7, and 5.5 mm in the SI, LL, and AP directions, respectively. The mean correlation error was 2.2 ± 0.9 mm. Conclusions: Data from online tracking indicated motion irregularities and correlation errors, necessitating an increased CTV-PTV margin of 3 mm. In 35% of cases, the motion variability exceeded 3 mm in one or more directions. We recommend verifying the correlation between CTV and surrogate individually for every patient, especially for targets with posterobasal localization where we observed the highest difference between the lead and CTV motion.
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