Stereotactic Radiotherapy for Brain Metastases: Imaging Tools and Dosimetric Predictive Factors for Radionecrosis

Radionecrosis (RN) is the most important side effect after stereotactic radiotherapy (SRT) for brain metastases, with a reported incidence ranging from 3% to 24%. To date, there are no unanimously accepted criteria for iconographic diagnosis of RN, as well as no definitive dose-constraints correlated with the onset of this late effect. We reviewed the current literature and gave an overview report on imaging options for the diagnosis of RN and on dosimetric parameters correlated with the onset of RN. We performed a PubMed literature search according to the preferred reporting items and meta-analysis (PRISMA) guidelines, and identified articles published within the last ten years, up to 31 December 2019. When analyzing data on diagnostic tools, perfusion magnetic resonance imaging (MRI) seems to be very useful allowing evaluation of the blood flow in the lesion using the relative cerebral blood volume (rCBV) and blood vessel integrity using relative peak weight (rPH). It is necessary to combine morphological with functional imaging in order to match information about lesion morphology, metabolism and blood-flow. Eventually, serial imaging follow-up is needed. Regarding dosimetric parameters, in radiosurgery (SRS) V12 < 8 cm3 and V10 < 10.5 cm3 of normal brain are the most reliable prognostic factors, whereas in hypo-fractionated stereotactic radiotherapy (HSRT) V18 and V21 are considered the main predictive independent risk factors of RN

Biparametric prostate MRI: impact of a deep learning-based software and of quantitative ADC values on the inter-reader agreement of experienced and inexperienced readers

Objective To investigate the impact of an artificial intelligence (AI) software and quantitative ADC (qADC) on the inter-reader agreement, diagnostic performance, and reporting times of prostate biparametric MRI (bpMRI) for experienced and inexperienced readers. Materials and methods A total of 170 multiparametric MRI (mpMRI) of patients with suspicion of prostate cancer (PCa) were retrospectively reviewed by one experienced and one inexperienced reader three times, following a wash-out period. First, only the bpMRI sequences, including T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI) sequences, and apparent diffusion coefficient (ADC) maps, were used. Then, bpMRI and quantitative ADC values were used. Lastly, bpMRI and the AI software were used. Inter-reader agreement between the two readers and between each reader and the mpMRI original reports was calculated. Detection rates and reporting times were calculated for each group. Results Inter-reader agreement with respect to mpMRI was moderate for bpMRI, Quantib, and qADC for both the inexperienced (weighted k of 0.42, 0.45, and 0.41, respectively) and the experienced radiologists (weighted k of 0.44, 0.46, and 0.42, respectively). Detection rate of PCa was similar between the inexperienced (0.24, 0.26, and 0.23) and the experienced reader (0.26, 0.27 and 0.27), for bpMRI, Quantib, and qADC, respectively. Reporting times were lower for Quantib (8.23, 7.11, and 9.87 min for the inexperienced reader and 5.62, 5.07, and 6.21 min for the experienced reader, for bpMRI, Quantib, and qADC, respectively). Conclusions AI and qADC did not have a significant impact on the diagnostic performance of both readers. The use of Quantib was associated with lower reporting times

Tomotherapy-based moderate hypofractionation for localized prostate cancer: a mono-institutional analysis

Background: To date, few studies have been published on image-guided helical tomotherapy (HT) in a moderate hypofractionation of localized PCa. We report outcome and toxicity of localized PCa patients treated with HT-based moderate hypofractionated radiotherapy. Materials and methods: 76 patients were retrospectively analyzed. A total dose of 60 Gy (20 x 3 Gy) or 67.5 Gy (25 x 2.7 Gy) was prescribed. The Chi2 test was used to analyze associations between toxicity and dosimetric and clinical parameters. The Cox proportional hazard regression model was used for multivariate analysis. Kaplan-Meier method was used for survival analysis. Results: median follow-up was 42.26 months [interquartile (IQR), 23–76). At 4-year, overall survival (OS) and metastasis-free survival (MFS) were 91% and 89%, respectively. At multivariate analysis, smoking habitude was associated with MFS [hazard ratio (HR) 7.32, 95% CI: 1.57–34.16, p = 0.011]. Acute and late grade ≥ 2 gastro-intestinal (GI) toxicity was observed in 6.5% and 2.6% of patients, respectively. Acute and late grade ≥ 2 genito-urinary (GU) toxicity were 31.5% and 3.9%. Four-year late GI and GU grade ≥ 2 toxicity were 3% and 7%, respectively. Acute GI toxicity was associated with statins medication (p = 0.04) and androgen deprivation therapy (p = 0.013). Acute GU toxicity was associated with the use of anticoagulants (p = 0.029) and antiaggregants (p = 0.013). Conclusions: HT-based moderate hypofractionation shows very low rates of toxicity. Smoking habitude is associated with the risk of developing metastases after radical treatment for localized PCa

Prognostic Genomic Tissue-Based Biomarkers in the Treatment of Localized Prostate Cancer

In localized prostate cancer clinicopathologic variables have been used to develop prognostic nomograms quantifying the probability of locally advanced disease, of pelvic lymph node and distant metastasis at diagnosis or the probability of recurrence after radical treatment of the primary tumor. These tools although essential in daily clinical practice for the management of such a heterogeneous disease, which can be cured with a wide spectrum of treatment strategies (i.e., active surveillance, RP and radiation therapy), do not allow the precise distinction of an indolent instead of an aggressive disease. In recent years, several prognostic biomarkers have been tested, combined with the currently available clinicopathologic prognostic tools, in order to improve the decision-making process. In the following article, we reviewed the literature of the last 10 years and gave an overview report on commercially available tissue-based biomarkers and more specifically on mRNA-based gene expression classifiers. To date, these genomic tests have been widely investigated, demonstrating rigorous quality criteria including reproducibility, linearity, analytical accuracy, precision, and a positive impact in the clinical decision-making process. Albeit data published in literature, the systematic use of these tests in prostate cancer is currently not recommended due to insufficient evidence

Post-operative radiotherapy in the management of metastatic inflammatory breast cancer

With this review, we aimed to describe the role of adjuvant radiotherapy in the therapeutic management of metastatic inflammatory breast cancer, a rare and aggressive disease historically characterized by high rates of recurrence and poor prognosis. In the context of a multimodality approach, Post-Mastectomy Radiotherapy (PMRT) affirms its role as an appriopriate treatment strategy to improve loco-regional tumor control in selected patients. Further validation in prospective trials is required to better define a standardized therapeutic management of this disease

Stereotactic Radiotherapy for Brain Metastases: Imaging Tools and Dosimetric Predictive Factors for Radionecrosis

Radionecrosis (RN) is the most important side effect after stereotactic radiotherapy (SRT) for brain metastases, with a reported incidence ranging from 3% to 24%. To date, there are no unanimously accepted criteria for iconographic diagnosis of RN, as well as no definitive dose-constraints correlated with the onset of this late effect. We reviewed the current literature and gave an overview report on imaging options for the diagnosis of RN and on dosimetric parameters correlated with the onset of RN. We performed a PubMed literature search according to the preferred reporting items and meta-analysis (PRISMA) guidelines, and identified articles published within the last ten years, up to 31 December 2019. When analyzing data on diagnostic tools, perfusion magnetic resonance imaging (MRI) seems to be very useful allowing evaluation of the blood flow in the lesion using the relative cerebral blood volume (rCBV) and blood vessel integrity using relative peak weight (rPH). It is necessary to combine morphological with functional imaging in order to match information about lesion morphology, metabolism and blood-flow. Eventually, serial imaging follow-up is needed. Regarding dosimetric parameters, in radiosurgery (SRS) V12 &lt; 8 cm3 and V10 &lt; 10.5 cm3 of normal brain are the most reliable prognostic factors, whereas in hypo-fractionated stereotactic radiotherapy (HSRT) V18 and V21 are considered the main predictive independent risk factors of RN

The Use of Cardiac Stereotactic Radiation Therapy (SBRT) to Manage Ventricular Tachycardia: A Case Report, Review of the Literature and Technical Notes

Background: among cardiac arrhythmias, ventricular tachycardia (VT) is one that can lead to cardiac death, although significant progress has been made in its treatment, including the use of implantable cardioverter-defibrillators (ICD) and radiofrequency catheter ablation. Nevertheless, long-term recurrence rates remain in about half of patients and drastically impact the patient’s quality of life. Moreover, recurrent ICD shocks are painful and are associated with higher mortality and worsening of heart failure. Recently, more and more experiences are demonstrating potential efficacy in the use of stereotactic body radiotherapy (SBRT) (also called cardiac radio-ablation) to treat this condition. In this paper, we report our experience in the use of cardiac radio-ablation for the treatment of refractory ventricular tachycardia with a focus on the technique used, along with a review of the literature and technical notes. Case presentation: an 81-year-old male patient with a long history of non-ischemic dilated cardiomyopathy and mechanical mitral prosthesis underwent a biventricular cardioverter defibrillator implant after atrial ventricular node ablation. At the end of 2021, the number of tachycardias increased significantly to about 10 episodes per day. After failure of medical treatment and conventional RT catheter ablation, the patient was treated with SBRT for a total dose of 25 Gy in a single session at the site of the ectopic focus. No acute toxicity was recorded. After SBRT (follow-up 7 months) no other VT episodes were recorded. Conclusion: SBRT appears to be safe and leads to a rapid reduction in arrhythmic storms as treatment for VT without acute toxicity, representing one of the most promising methods for treating VT storms

Stereotactic Body Radiation Therapy (SBRT) for Oligorecurrent/Oligoprogressive Mediastinal and Hilar Lymph Node Metastasis: A Systematic Review

Introduction: Mediastinal or hilar lymph node metastases are a challenging condition in patients affected by solid tumors. Stereotactic body radiation therapy (SBRT) could play a crucial role in the therapeutic management and in the so-called “no-fly zone”, delivering high doses of radiation in relatively few treatment fractions with excellent sparing of healthy surrounding tissues and low toxicity. The aim of this systematic review is to evaluate the feasibility and tolerability of SBRT in the treatment of mediastinal and hilar lesions with particular regard to the radiotherapy doses, dose constraints for organs at risk, and clinical outcomes. Materials and methods: Two blinded investigators performed a critical review of the Medline, Web of Knowledge, Google Scholar, Scopus, and Cochrane databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement (PRISMA), starting from a specific question: What is the clinical impact of SBRT for the treatment of oligorecurrent/oligoprogressive mediastinal and hilar metastasis? All retrospective and prospective clinical trials published in English up to February 2022 were analyzed. Results: A total of 552 articles were identified and 12 of them were selected with a total number of 478 patients treated with SBRT for mediastinal or hilar node recurrence. All the studies are retrospective, published between 2015 and 2021 with a median follow-up ranging from 12 to 42.2 months. Studies following SBRT for lung lesions or retreatments after thorax radiotherapy for stage III lung cancer were also included. The studies showed extensive heterogeneity in terms of patient and treatment characteristics. Non-small cell lung cancer was the most frequently reported histology. Different dose schemes were used, with a higher prevalence of 4–8 Gy in 5 or 6 fractions, but dose escalation was also used up to 52 Gy in 4 fractions with dose constraints mainly derived from RTOG 0813 trial. The radiotherapy technique most frequently used was volumetric modulated arc therapy (VMAT) with a median PTV volume ranging from 7 to 25.7 cc. The clinical outcome seems to be very encouraging with 1-year local control (LC), overall survival (OS) and progression-free survival (PFS) rates ranging from 84 to 94%, 53 to 88% and 23 to 53.9%, respectively. Half of the studies did not report toxicity greater than G3 and only five cases of fatal toxicity were reported. CONCLUSIONS: From the present review, it is not possible to draw definitive conclusions because of the heterogeneity of the studies analyzed. However, SBRT appears to be a safe and effective option in the treatment of mediastinal and hilar lymph node recurrence, with a good toxicity profile. Its use in clinical practice is still limited, and there is extensive heterogeneity in patient selection and fractionation schedules. Good performance status, small PTV volume, absence of previous thoracic irradiation, and administration of a high biologically effective dose (BED) seem to be factors that correlate with greater local control and better survival rates. In the presence of symptoms related to the thoracic lymph nodes, SBRT determines a rapid control that lasts over time. We look forward to the prospective studies that are underway for definitive conclusions