Artificial intelligence applied to image-guided radiation therapy (IGRT): a systematic review by the Young Group of the Italian Association of Radiotherapy and Clinical Oncology (yAIRO).

INTRODUCTION: The advent of image-guided radiation therapy (IGRT) has recently changed the workflow of radiation treatments by ensuring highly collimated treatments. Artificial intelligence (AI) and radiomics are tools that have shown promising results for diagnosis, treatment optimization and outcome prediction. This review aims to assess the impact of AI and radiomics on modern IGRT modalities in RT. METHODS: A PubMed/MEDLINE and Embase systematic review was conducted to investigate the impact of radiomics and AI to modern IGRT modalities. The search strategy was "Radiomics" AND "Cone Beam Computed Tomography"; "Radiomics" AND "Magnetic Resonance guided Radiotherapy"; "Radiomics" AND "on board Magnetic Resonance Radiotherapy"; "Artificial Intelligence" AND "Cone Beam Computed Tomography"; "Artificial Intelligence" AND "Magnetic Resonance guided Radiotherapy"; "Artificial Intelligence" AND "on board Magnetic Resonance Radiotherapy" and only original articles up to 01.11.2022 were considered. RESULTS: A total of 402 studies were obtained using the previously mentioned search strategy on PubMed and Embase. The analysis was performed on a total of 84 papers obtained following the complete selection process. Radiomics application to IGRT was analyzed in 23 papers, while a total 61 papers were focused on the impact of AI on IGRT techniques. DISCUSSION: AI and radiomics seem to significantly impact IGRT in all the phases of RT workflow, even if the evidence in the literature is based on retrospective data. Further studies are needed to confirm these tools' potential and provide a stronger correlation with clinical outcomes and gold-standard treatment strategies.

Contact skin radiotherapy (brachytherapy) for the treatment of non-melanoma skin cancers during COVID-19 pandemic.

In the context of the SARS-CoV-2 pandemic, it is important to ensure the quality of cancer treatment as well as patients and health professionals' safety. Individual-based treatment options should be considered in patients with advanced epithelial skin cancer, who are typically elderly and frail. Aim of this study was to assess feasibility and safety of Contact Skin Radiation Therapy (CSRT) to treat basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) during SARS-CoV-2 pandemic. Patients with advanced and difficult-to-treat BCC or SCC were discussed at skin multidisciplinary tumor board (S-MDTB) from February the 21st to May the 4th (phase 1 Italian Pandemic) and retrospectively analyzed. Patient's triage following internal recommendations was daily performed. CSRT was delivered in 8 fractions of 5 Gy each, twice a day. Beyond the clinical outcomes, treatment success indicators, such as the completion of CSRT without SARS-CoV-2 occurrence, were identified to evaluate the feasibility of CSRT during pandemic. A post-treatment psychological assessment regarding patient's safety perception was performed. Six male patients (median age 80 years; range 62-92) with histologically confirmed BCC or SCC were treated with CSRT. Complete clinical remission was achieved in 5/6 patients (83.4%). No high-grade acute toxicities occurred during treatment. No patients or healthcare personnel developed SARS-CoV-2 infection. All the treatment success indicators were achieved. CSRT represents a safe, and feasible treatment option even during the pandemic emergency period. Hypofractionation could be an option to reduce total number of fractions and, consequently, infective risk exposition.

Multidisciplinary personalized approach in the management of vulvar cancer - the Vul.Can Team experience.

INTRODUCTION: Multidisciplinary treatment strategy involving adjuvant radiotherapy for advanced vulvar cancer could be useful in offering the best personalized clinical approach. In 2013, the VULvar CANcer Multi-Disciplinary Team (Vul.Can MDT) was set up in our institution, in order to share knowledge and expertise, high-quality diagnosis, and evidence-based decision making in the context of personalized medicine. The aim of this observational study was to report on our series of vulvar cancer patients managed postoperatively with radiotherapy within the framework of a formal multidisciplinary tumor board. METHODS: Coupling surgical and oncological international guidelines with "case-by-case" discussions, a multi-specialist consensus was progressively reached and internal recommendations were developed and introduced in the daily routine. Data from vulvar cancer patients who underwent primary surgery and adjuvant radiotherapy throughout a 5-year period were retrospectively collected. Actuarial local control was the primary endpoint, while secondary end-points were acute and late toxicities, disease-free survival, and overall survival. Toxicity was evaluated according to the Common Toxicity Criteria Adverse Event v 4.0 scale. RESULTS: The analysis included 35 patients with squamous vulvar cancer treated with adjuvant radiotherapy±chemotherapy, from April 2013 to September 2017. Median age was 70 years (range 18-87), all patients underwent surgery followed by concomitant chemoradiation (45.7%) or radiotherapy alone (54.3%). The median prophylactic dose on lymphatic drainage was 45 Gy, while positive nodes and perineal area received 51.2 Gy and 52.6 Gy, respectively. Chemotherapy involved the cisplatin-based regimen (45.7%)±5-fluorouracil (37.1%). Median follow-up was 32 months (range 6-72): the 24-months local control, disease-free survival, and actuarial overall survival rates were 88.6%, 82.0%, and 91.0%, respectively. Low rates of severe acute (12%) and late (3%) toxicities occurred. DISCUSSION: The outcomes of this series support the benefit of a multidisciplinary personalized approach in the management of vulvar cancer.

Interventional radiotherapy (brachytherapy) for re-irradiation of recurrent head and neck malignancies: oncologic outcomes and morbidity.

Objective: Management of recurrent head and neck cancer (HNC) is challenging. One option in previously irradiated patients is re-irradiation using interventional radiotherapy (IRT), the modern form of brachytherapy. Re-irradiation using IRT can be delivered as an exclusive strategy for salvage or through a postoperative or perioperative approach after salvage surgery. The aim of the present study is to analyse a bicentric Italian series focusing on the use of IRT as a re-irradiation modality and assess the resulting evidence concerning oncologic outcomes and morbidity. Methods: This is a retrospective study performed in two referral centres in Italy: Policlinico Universitario Agostino Gemelli in Rome and Azienda Ospedaliera Universitaria in Sassari. All patients who had previously received a full course of external beam RT and have been re-irradiated using high-dose-rate IRT between December 2010 and June 2023 were included. Patients were retreated either by a combination of surgery and perioperative (either endocavitary or interstitial) IRT or by exclusive interstitial IRT. Results: Thirty-four patients were included in the present series, 2 of whom underwent more than one IRT re-irradiation. Notably, no patient reported specific IRT-related toxicities. Median follow-up, excluding patients who died of HNC, was 24.5 months. Two-year local relapse-free survival was 26%, disease-specific survival 39.1%, and overall survival 36.6%. Conclusions: The present series is the largest reported experience of re-irradiation by IRT for HNC in Italy. The very low rate of toxicity confirms IRT as the safest re-irradiation modality. It is noteworthy to underline that IRT is a multidisciplinary strategy based on the close cooperation between surgeons and radiation oncologists during every phase, from the recommendation of treatment and implantation in the operating theatre, to its prescription and dose painting.

Impact of bias field correction on 0.35 T pelvic MR images: evaluation on generative adversarial network-based OARs' auto-segmentation and visual grading assessment.

Purpose: Magnetic resonance imaging (MRI)-guided radiotherapy enables adaptive treatment plans based on daily anatomical changes and accurate organ visualization. However, the bias field artifact can compromise image quality, affecting diagnostic accuracy and quantitative analyses. This study aims to assess the impact of bias field correction on 0.35 T pelvis MRIs by evaluating clinical anatomy visualization and generative adversarial network (GAN) auto-segmentation performance. Materials and methods: 3D simulation MRIs from 60 prostate cancer patients treated on MR-Linac (0.35 T) were collected and preprocessed with the N4ITK algorithm for bias field correction. A 3D GAN architecture was trained, validated, and tested on 40, 10, and 10 patients, respectively, to auto-segment the organs at risk (OARs) rectum and bladder. The GAN was trained and evaluated either with the original or the bias-corrected MRIs. The Dice similarity coefficient (DSC) and 95th percentile Hausdorff distance (HD95th) were computed for the segmented volumes of each patient. The Wilcoxon signed-rank test assessed the statistical difference of the metrics within OARs, both with and without bias field correction. Five radiation oncologists blindly scored 22 randomly chosen patients in terms of overall image quality and visibility of boundaries (prostate, rectum, bladder, seminal vesicles) of the original and bias-corrected MRIs. Bennett's S score and Fleiss' kappa were used to assess the pairwise interrater agreement and the interrater agreement among all the observers, respectively. Results: In the test set, the GAN trained and evaluated on original and bias-corrected MRIs showed DSC/HD95th of 0.92/5.63 mm and 0.92/5.91 mm for the bladder and 0.84/10.61 mm and 0.83/9.71 mm for the rectum. No statistical differences in the distribution of the evaluation metrics were found neither for the bladder (DSC: p = 0.07; HD95th: p = 0.35) nor for the rectum (DSC: p = 0.32; HD95th: p = 0.63). From the clinical visual grading assessment, the bias-corrected MRI resulted mostly in either no change or an improvement of the image quality and visualization of the organs' boundaries compared with the original MRI. Conclusion: The bias field correction did not improve the anatomy visualization from a clinical point of view and the OARs' auto-segmentation outputs generated by the GAN.

Stereotactic Radiotherapy for penile metastasis: case report and systematic literature review.

Introduction Penile metastases (PM) are a rare clinical presentation mainly related to advanced stages of disease. Considering the low incidence, an optimal treatment approach has not yet been defined; surgery, chemotherapy, and radiotherapy are different options used in the vast majority with palliative intent. The advances in modern RT can represent an innovative tool in PM management and a curative option. This paper aims to report the case of a PM patient treated with Stereotactic Body Radiotherapy (SBRT) and perform a systematic literature review of current evidence on the RT approach to PM. Case report We reported the case of an 80-year-old patient with PM from primary bladder cancer. Following the surgical approach for the primary tumor, evidence of PM was shown, and the patient was admitted to SBRT treatment on PM after an adjuvant RT course on the pelvis. A 25 Gy in 5 fractions SBRT treatment was performed, and a complete clinical response was shown at the first follow-up. Methods A Pubmed/MEDLINE and Embase systematic review was carried out. The search strategy terms were [('penile metastasis'/exp OR 'penile metastasis' OR (penile AND ('metastasis'/exp OR metastasis))) AND ('radiotherapy'/exp OR radiotherapy)] and only original articles up to the 24.10.2023 were considered. Results A total of 174 studies were obtained using the previously mentioned search strategy, and the analysis was performed on 15 papers obtained following the complete selection process. All reported evidence was focused on the palliative approach of PM showing good results in terms of symptom control. Discussion The potential role of modern RT in the management of PM has yet to be defined. The reported case showed the feasibility and the clinical impact of SBRT in PM treatment.

Stereotactic Radiotherapy in Early-Stage Breast Cancer in Neoadjuvant and Exclusive Settings: A Systematic Review.

INTRODUCTION: Breast cancer (BC) is one of the most common tumors; better screening policies and multidisciplinary approach allow personalized treatment. Radiotherapy (RT) plays a central role in the multimodal approach in BC, and recent evidence has shown the non-inferiority of hypofractionated treatments. The aim of this study was to describe the feasibility and validity of stereotactic RT (SBRT) in BC in a neoadjuvant and exclusive setting. METHODS: A PubMed/MEDLINE and Embase systematic review was conducted to assess the role of radiomics in BC. The search strategy was "breast [All Fields] AND "stereotactic" [All Fields] AND "radiotherapy" [All Fields]" and only original articles referred to BC in humans in the English language were considered. RESULTS: A total of 2,149 studies were obtained using the mentioned search strategy on PubMed and Embase. After the complete selection process, a total of 12 papers were considered eligible for the analysis of the results. SBRT in BC was described in 8 studies regarding neoadjuvant approach and 4 papers regarding exclusive approach. CONCLUSIONS: Relative low toxicity rates, the reduced treatment volumes in the neoadjuvant setting, and the possibility to replace surgery when not feasible in exclusive setting resulted to be main advantages for SBRT in BC. Current evidence shows that both the neoadjuvant and the definitive settings seem to be promising clinical scenarios for SBRT, especially for EBC.

KIT 1 (Keep in Touch) Project-Televisits for Cancer Patients during Italian Lockdown for COVID-19 Pandemic: The Real-World Experience of Establishing a Telemedicine System.

To evaluate the adoption of an integrated eHealth platform for televisit/monitoring/consultation during the COVID-19 pandemic. METHODS: During the lockdown imposed by the Italian government during the COVID19 pandemic spread, a dedicated multi-professional working group was set up in the Radiation Oncology Department with the primary aim of reducing patients' exposure to COVID-19 by adopting de-centralized/remote consultation methodologies. Each patient's clinical history was screened before the visit to assess if a traditional clinical visit would be recommended or if a remote evaluation was to be preferred. Real world data (RWD) in the form of patient-reported outcomes (PROMs) and patient reported experiences (PREMs) were collected from patients who underwent televisit/teleconsultation through the eHealth platform. RESULTS: During the lockdown period (from 8 March to 4 May 2020) a total of 1956 visits were managed. A total of 983 (50.26%) of these visits were performed via email (to apply for and to upload of documents) and phone call management; 31 visits (1.58%) were performed using the eHealth system. Substantially, all patients found the eHealth platform useful and user-friendly, consistently indicating that this type of service would also be useful after the pandemic. CONCLUSIONS: The rapid implementation of an eHealth system was feasible and well-accepted by the patients during the pandemic. However, we believe that further evidence is to be generated to further support large-scale adoption.

Magnetic resonance guided SBRT reirradiation in locally recurrent prostate cancer: a multicentric retrospective analysis.

AIMS: Reirradiation of prostate cancer (PC) local recurrences represents an emerging challenge for current radiotherapy. In this context, stereotactic body radiation therapy (SBRT) allows the delivery of high doses, with curative intent. Magnetic Resonance guided Radiation Therapy (MRgRT) has shown promising results in terms of safety, feasibility and efficacy of delivering SBRT thanks to the enhanced soft tissue contrast and the online adaptive workflow. This multicentric retrospective analysis evaluates the feasibility and efficacy of PC reirradiation, using a 0.35 T hybrid MR delivery unit. METHODS: Patients affected by local recurrences of PC and treated in five institutions between 2019 and 2022 were retrospectively collected. All patients had undergone previous Radiation Therapy (RT) in definitive or adjuvant setting. Re-treatment MRgSBRT was delivered with a total dose ranging from 25 to 40 Gy in 5 fractions. Toxicity according to CTCAE v 5.0 and treatment response were assessed at the end of the treatment and at follow-up. RESULTS: Eighteen patients were included in this analysis. All patients had previously undergone external beam radiation therapy (EBRT) up to a total dose of 59.36 to 80 Gy. Median cumulative biologically effective dose (BED) of SBRT re-treatment was 213,3 Gy (103,1-560), considering an α/ß of 1.5. Complete response was achieved in 4 patients (22.2%). No grade ≥ 2 acute genitourinary (GU) toxicity events were recorded, while gastrointestinal (GI) acute toxicity events occurred in 4 patients (22.2%). CONCLUSION: The low rates of acute toxicity of this experience encourages considering MRgSBRT a feasibile therapeutic approach for the treatment of clinically relapsed PC. Accurate gating of target volumes, the online adaptive planning workflow and the high definition of MRI treatment images allow delivering high doses to the PTV while efficiently sparing organs at risk (OARs).

Covid-19 and radiotherapy: a systematic review after 2 years of pandemic.

Introduction: Following the Covid-19 pandemic spread, changes in clinical practice were necessary to limit the pandemic diffusion. Also, oncological practice has undergone changes with radiotherapy (RT) treatments playing a key role.Although several experiences have been published, the aim of this review is to summarize the current evidence after 2 years of pandemic to provide useful conclusions for clinicians. Methods: A Pubmed/MEDLINE and Embase systematic review was conducted. The search strategy was "Covid AND Radiotherapy" and only original articles in the English language were considered. Results: A total of 2.733 papers were obtained using the mentioned search strategy. After the complete selection process, a total of 281 papers were considered eligible for the analysis of the results. Discussion: RT has played a key role in Covid-19 pandemic as it has proved more resilient than surgery and chemotherapy. The impact of the accelerated use of hypofractionated RT and telemedicine will make these strategies central also in the post-pandemic period.

Bullous pemphigoid and radiotherapy: Case report and literature review update.

Bullous pemphigoid (BP) is a common autoimmune bullous disease generally occurring in elderly patients. Itchy and tense blisters on normal skin or erythematous and edematous lesions on the trunk and extremities usually characterize BP. Trigger factors are still unclear while several case reports suggest a potential role of radiotherapy (RT) as BP trigger for disease onset or recrudescence. A review was performed to provide an update of literature. A case report of a patient affected by BP undergoing two radiotherapy courses for a primary breast cancer was also reported. A comprehensive review of the published literature was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The review included studies describing BP and its relationships with RT treatments. A total of 13 articles were reviewed. Studies characteristics analysis resulted in eleven case reports, one case series and one large-scale case- control study. Literature update confirms the existence of a reasonable connection between RT and BP. Case report showed that a multidisciplinary management seems to assure the feasibility of RT in patients affected by BP, not depriving them of standard therapeutic opportunities.

Radiofrequency Thermoablation and Hypofractionated Radiotherapy Combined Treatment for Bone Metastases: A Retrospective Study.

INTRODUCTION: Bone metastases (BMs) are the common cause of cancer-related pain, as approximately 45% of cancer patients suffer from bone pain (BP). Radiotherapy (RT) is well established as BP treatment strategy; also, other approaches have been shown to be effective in this setting. Radiofrequency thermoablation (RFA) in a combined strategy with RT appears to be feasible and effective in the treatment of metastatic BP ensuring a better quality of life. Aim of this retrospective study was to describe a case series of patients with painful osteolytic lesions at risk of fracture treated with the RFA-RT combined approach, analyzing local control and pain control as outcomes. METHODS: Data of all patients with BM treated with combined approach in our center from April 2016 to June 2020 were retrospectively analyzed. Patients underwent RFA followed by cementoplasty on the same day and RT in a second phase. RT dose ranged between 30 and 37.5 Gy in 5/10 fractions. BP was evaluated according to the numeric rating scale (NRS), at the beginning of treatment and at 1, 2, 3, 6, 9, and 12 months from the end of combined treatment. RESULTS: A total of 27 patients were treated from April 2016 to June 2020 with RFA-RT combined approach. The large majority of patients underwent stereotactic body radiotherapy (SBRT) (23/27). All patients experienced an NRS value decrease >2 at 1 month and between the first and second months. NRS mean value reached 0 at 3, 6, 9, and 12 months' evaluations. DISCUSSION/CONCLUSION: The results of this retrospective analysis of patients treated with RFA-RT combined approach for BP support its safety and efficacy in terms of pain reduction. SBRT role in this combined approach has to be investigated in randomized trials.

Heel Spur and Radiotherapy: Case Report and Systematic Literature Review.

Heel spur is a chronic inflammatory condition causing pain and other typical symptoms. Therapeutic recommendations include the use of several drug or orthotic/physical therapies, performed alone or in combination. Surgery is usually reserved for refractory conditions. Radiotherapy has been shown to ensure good clinical outcomes in this clinical setting. A systematic review was performed to describe the feasibility and effectiveness of radiotherapy in the treatment of heel spur, evaluating its role in alleviating pain and consequently ensuring a better quality of life. A case report of 45-year-old patient treated for refractary right hindfoot pain was reported. A single fraction of 6 Gy RT was delivered with symptomatic complete response at 2 months observed. A systematic database search was conducted according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The systematic review included studies describing heel spur treatment and providing complete information about radiotherapy. Fifteen articles published between 1996 and 2020 were reviewed. Study characteristic analysis resulted in seven prospective randomized studies and eight retrospective studies. Radiotherapy of painful heel spur seems to be safe and effective, with high response rates even at low doses and with an overall favorable toxicity profile. Predictive parameters and modern tailored treatment should be investigated with further studies.

Immunosuppressive treatment and radiotherapy in kidney transplant patients: A systematic review.

BACKGROUND: Immunosuppression (IS) therapy may contribute to cancer development. Some authors have proposed to reduce immunosuppression drugs dose in case of viral infections, in immunosuppression-related diseases, and in patients undergoing radiotherapy. The present analysis reports the results of a systematic review on kidney transplant recipients undergoing immunosuppression and radiotherapy. AIM: To define if it is necessary reduce immunosuppression drugs during radiotherapy. METHODS: The literature search was based on three electronic databases (Pubmed, Scopus, and Web of Science) using selected keywords linked through the "AND" and "OR" Boolean operators to build specific strings for each electronic search engine. Two researchers independently screened the citations, and disagreement was resolved by discussion or through the intervention of a third author. The review was conducted and reported according to the PRISMA statement. Extracted data were narratively synthesized, and, where possible, frequencies, percentages, and ranges were calculated. RESULTS: The literature search resulted in 147 citations. After abstracts screening, 21 records were selected for full-text evaluation. Fifteen of these were excluded, leaving six papers considered suitable for analysis. There is still no clear evidence that withdrawing antimetabolites and/or calcineurin inhibitors and/or mammalian target of rapamycin-inhibitors, as opposed to continuing maintenance IS, improves patient survival in kidney transplant recipients with cancer undergoing radiotherapy. Only few retrospective studies on small cancer patient cohorts are available in this setting, but without comparison of different immunosuppression treatments. Even where immunosuppression therapy was described, patient survival seemed to be correlated only with cancer stage and type. CONCLUSION: The results of this systematic review do not support the reduction of immunosuppression dose in patients undergoing radiotherapy.

Dosimetric Impact of Inter-Fraction Variability in the Treatment of Breast Cancer: Towards New Criteria to Evaluate the Appropriateness of Online Adaptive Radiotherapy.

Purpose: As a discipline in its infancy, online adaptive RT (ART) needs new ontologies and ad hoc criteria to evaluate the appropriateness of its use in clinical practice. In this experience, we propose a predictive model able to quantify the dosimetric impact due to daily inter-fraction variability in a standard RT breast treatment, to identify in advance the treatment fractions where patients might benefit from an online ART approach. Methods: The study was focused on right breast cancer patients treated using standard adjuvant RT on an artificial intelligence (AI)-based linear accelerator. Patients were treated with daily CBCT images and without online adaptation, prescribing 40.05 Gy in 15 fractions, with four IMRT tangential beams. ESTRO guidelines were followed for the delineation on planning CT (pCT) of organs at risk and targets. For each patient, all the CBCT images were rigidly aligned to pCT: CTV and PTV were manually re-contoured and the original treatment plan was recalculated. Various radiological parameters were measured on CBCT images, to quantify inter-fraction variability present in each RT fraction after the couch shifts compensation. The variation of these parameters was correlated with the variation of V95% of PTV (ΔV95%) using the Wilcoxon Mann-Whitney test. Fractions where ΔV95% > 2% were considered as adverse events. A logistic regression model was calculated considering the most significant parameter, and its performance was quantified with a receiver operating characteristic (ROC) curve. Results: A total of 75 fractions on 5 patients were analyzed. The body variation between daily CBCT and pCT along the beam axis with the highest MU was identified as the best predictor (p = 0.002). The predictive model showed an area under ROC curve of 0.86 (95% CI, 0.82-0.99) with a sensitivity of 85.7% and a specificity of 83.8% at the best threshold, which was equal to 3 mm. Conclusion: A novel strategy to identify treatment fractions that may benefit online ART was proposed. After image alignment, the measure of body difference between daily CBCT and pCT can be considered as an indirect estimator of V95% PTV variation: a difference larger than 3 mm will result in a V95% decrease larger than 2%. A larger number of observations is needed to confirm the results of this hypothesis-generating study.

New dosimetric parameters to predict ano-rectal toxicity during radiotherapy treatment.

PURPOSE: Radiotherapy is essential in the treatment of locally advanced rectal cancer. Side effects of radiotherapy in the treatment of rectal cancer have a great effect on quality of life. The aim of this retrospective study is to evaluate the correlation between dosimetric parameters and acute toxicity in rectal cancer patients. METHODS: We analyzed the Dose Volume Histogram parameters for both the target structures and the Organs at risk of 89 patients. A dedicated statistical analysis was performed for all the acute toxicities showing a frequency rate higher than 20%. A linear logistic regression model was elaborated using the variable showing the highest level of significance at the univariate analysis. RESULTS: The occurrence of proctitis was significantly correlated with three dosimetric parameters: D98% of low ano-rectum, D98% and Dmean of low ano-rectum wall. A predictive linear logistic regression model reports that the D98% of the wall of the low ano-rectum must be < 38.5 Gy to decrease the rate of proctitis. A general analysis on grade 2 acute toxicity occurrence reported that it was correlated with D98% of low ano rectum. CONCLUSIONS: Two dose constraints were elaborated: D98%<33.5 Gy for low ano rectum to prevent grade 2 acute toxicity and D98%<25 Gy for low ano-rectum wall to prevent proctitis (grade 1 or superior).

Five-Fraction Stereotactic Radiotherapy for Brain Metastases: A Single-Institution Experience on Different Dose Schedules.

INTRODUCTION: The most common intracranial neoplasm diagnosed in adults are brain metastases (BrM). The benefit in terms of clinical control and toxicity for stereotactic radiotherapy (SRT) has been investigated for patients with low load of BrM. AIM: The aim of this single-institution experience was to investigate the best dose schedule for five-fraction SRT (FFSRT). METHODS: A retrospective analysis of patients treated for BrM with different dose schedules of FFSRT was performed. Local control (LC) and clinical outcomes were evaluated with magnetic resonance imaging at 3, 6, and 9 months. Toxicity data were also collected. RESULTS: A total of 41 patients treated from November 2016 to September 2020 were enrolled in the analysis. Non-small cell lung cancer (51.2%) and breast cancer (24.3%) represented the most frequent primitive tumors. Treatment was performed on 5 consecutive days with prescribed dose ranging from 30 to 40 Gy, prescribed to the 95% isodose line that covered at least 98% of the gross tumor volume. Statistically significant differences (p = 0.025) with higher LC rates for dose schedules >6 Gy for fractions. Toxicity rates were not found to be higher than G1. CONCLUSION: The results of this retrospective analysis suggest that FFSRT for BrM seems to be safe and feasible. Our results also underline that a total dose lower than 30 Gy in 5 fractions should not be used due to the expected minor LC.

New fractionations in breast cancer: a dosimetric study of 3D-CRT versus VMAT.

INTRODUCTION: Adjuvant radiation therapy (RT) following primary surgery in women affected by early breast cancer (EBC) plays a central role in reducing local recurrences and overall mortality. The FAST-FORWARD trial recently demonstrated that 1-week hypofractionated adjuvant RT is not inferior to the standard schedule in terms of local relapse, cosmetic outcomes and toxicity. The aim of this in silico study was to evaluate the dosimetric aspects of a 1-week RT course, administered through volumetric modulated arc therapy (VMAT), compared with traditional three-dimensional conformal radiation therapy (3D-CRT) with tangential fields. METHODS: Patients affected by left-side EBC undergoing adjuvant RT were selected. ESTRO guidelines for the clinical target volume (CTV) delineation and FAST-FORWARD protocol for CTV to planning target volume (PTV) margin definition were followed. Total prescribed dose was 26 Gy in five fractions. The homogeneity index (HI) and the global conformity index (GCI) were taken into account for planning and dose distribution optimisation purposes. Both 3D-CRT tangential fields and VMAT plans were generated for each patient. RESULTS: The analysis included 21 patients. PTV coverage comparison between 3D-CRT and VMAT plans showed significant increases for GCI (P < 0.05) in VMAT technique; no statistically significant differences were observed regarding HI. For organs at risks (OAR), statistically significant increases were observed in terms of skin V103% (P < 0.002) and ipsilateral lung V30% (P < 0.05) with 3D-CRT and of heart V5% (P < 0.05) with VMAT technique. CONCLUSIONS: This in silico study showed that both 3D-CRT and VMAT are dosimetrically feasible techniques in the framework of 1-week hypofractionated treatments for left EBC.

The impact of radiomics in diagnosis and staging of pancreatic cancer.

Introduction: Pancreatic cancer (PC) is one of the most aggressive tumours, and better risk stratification among patients is required to provide tailored treatment. The meaning of radiomics and texture analysis as predictive techniques are not already systematically assessed. The aim of this study is to assess the role of radiomics in PC. Methods: A PubMed/MEDLINE and Embase systematic review was conducted to assess the role of radiomics in PC. The search strategy was 'radiomics [All Fields] AND ("pancreas" [MeSH Terms] OR "pancreas" [All Fields] OR "pancreatic" [All Fields])' and only original articles referred to PC in humans in the English language were considered. Results: A total of 123 studies and 183 studies were obtained using the mentioned search strategy on PubMed and Embase, respectively. After the complete selection process, a total of 56 papers were considered eligible for the analysis of the results. Radiomics methods were applied in PC for assessment technical feasibility and reproducibility aspects analysis, risk stratification, biologic or genomic status prediction and treatment response prediction. Discussion: Radiomics seems to be a promising approach to evaluate PC from diagnosis to treatment response prediction. Further and larger studies are required to confirm the role and allowed to include radiomics parameter in a comprehensive decision support system.

The Added Value of [18F]Choline PET/CT in Low-Risk Prostate Cancer Staging: A Case Report.

In the management of prostate cancer (PCa), correct staging is crucial in order to assess the right therapeutic approach. [18F]Choline PET/CT has been shown to provide more accurate staging information than conventional imaging approaches. The aim of this paper is to provide a real practice demonstration of the impact of [18F]Choline PET/CT on low-risk prostate cancer staging and clinical management. We report a 64-year-old man with biochemical PCa recurrence diagnosis after transurethral resection of the prostate. The patient, after the detection of an increased level of PSA, underwent multi-parametric prostate magnetic resonance imaging (mpMRI) that did not show evidence of disease. The patient was admitted to perform [18F]Choline PET/CT that showed a macroscopic prostate recurrence. Patient underwent photon external beam radiation therapy (EBRT) treatment, and [18F]Choline PET/CT was also used to define treatment volumes. At 3- and 6-month clinical follow-up evaluations, no late toxicity was detected and a significant reduction in PSA value was shown. Therefore, our case highlights the potential usefulness of [18F]Choline PET/CT for the staging of low-risk prostate cancer and its impact on the management and quality of life of such patients. The presented case should urge the scientific community to enhance larger and multicentric studies, assessing more extensively the potential impact of [18F]Choline PET/CT in this clinical scenario.