Early clinical experience with volumetric modulated arc therapy in head and neck cancer patients

<p>Abstract</p> <p>Background</p> <p>To report about early clinical experience in radiation treatment of head and neck cancer of different sites and histology by volumetric modulated arcs with the RapidArc technology.</p> <p>Methods</p> <p>During 2009, 45 patients were treated at Istituto Clinico Humanitas with RapidArc (28 males and 17 females, median age 65 years). Of these, 78% received concomitant chemotherapy. Thirty-six patients were treated as exclusive curative intent (group A), three as postoperative curative intent (group B) and six with sinonasal tumours (group C). Dose prescription was at Planning Target Volumes (PTV) with simultaneous integrated boost: 54.45Gy and 69.96Gy in 33 fractions (group A); 54.45Gy and 66Gy in 33 fractions (group B) and 55Gy in 25 fractions (group C).</p> <p>Results</p> <p>Concerning planning optimization strategies and constraints, as per PTV coverage, for all groups, D_98%> 95% and V_95%> 99%. As regards organs at risk, all planning objectives were respected, and this was correlated with observed acute toxicity rates. Only 28% of patients experienced G3 mucositis, 14% G3 dermitis 44% had G2 dysphagia. Nobody required feeding tubes to be placed during treatment. Acute toxicity is also related to chemotherapy. Two patients interrupted the course of radiotherapy because of a quick worsening of general clinical condition.</p> <p>Conclusions</p> <p>These preliminary results stated that volumetric modulated arc therapy in locally advanced head and neck cancers is feasible and effective, with acceptable toxicities.</p

Multimodal imaging for clinical target volume definition in prone whole-breast irradiation: a single institution experience

Aim: The aim was identification of reference structures for breast clinical target volume (CTV) in prone position, throughout image fusion process. Materials & methods: We analyzed breast glandular tissue distribution in 20 diagnostic MRIs, referring to structures reported in ESTRO guidelines for supine irradiation. The volume containing breast glandular tissue in all cases was defined as MRI prone CTV (MRIpCTV). Then in ten subsequent patients planned for prone irradiation, MRI and computed tomography (CT) simulation was acquired. MRIpCTV was defined followed by our findings and transferred to CT for definitive delineation. Results: MRIpCTV was defined by the caudal edge of clavicular head, 3 mm above inframammary fold, by the medial thoracic artery, by a plane passing through the lateral surface of pectoralis muscles, by the anterior surface of pectoralis muscles and 3 mm from the skin. Deformed CTV was consistent with anatomy on CT; the limits chosen for MRIpCTV fit adequately also for CT. Conclusion: Prone irradiation is an alternative set up for selected cases, so the sample is very small. However, our suggestions could be of aid in defining prone CTV. The good consistency between MRI and CT seems to confirm that MRI may be unnecessary in routine practice

Spotting local environments in self-assembled monolayer-protected gold nanoparticles

Organic-inorganic (O-I) nanomaterials are versatile platforms for an incredible high number of applications, ranging from heterogeneous catalysis, molecular sensing, cell targeting, imaging, cancer diagnosis and therapy, just to name a few. Much of their potential stems from the unique control of organic environments around inorganic sites within a single O-I nanomaterial, which allows for new properties inaccessible using purely organic or inorganic materials. Structural and mechanistic characterization plays a key role in understanding and rationally designing such hybrid nanoconstructs. Here, we introduce a general methodology to identify and classify local (supra)molecular environments in an archetypal class of O-I nanomaterials, i.e. self-assembled monolayer-protected gold nanoparticles (SAM-AuNPs). By using an atomistic machine-learning guided workflow based on the Smooth Overlap of Atomic Positions (SOAP) descriptor, we analyze a collection of chemically different SAM-AuNPs, and detect and compare local environments in a way that is agnostic and automated, i.e. with no need of a-priori information and minimal user intervention. In addition, the computational results coupled with experimental electron spin resonance measurements prove that is possible to have more than one local environment inside SAMs, being thickness of the organic shell and solvation primary factors in determining number and nature of multiple co-existing environments. These indications are extended to complex mixed hydrophilic-hydrophobic SAMs. This work demonstrates that it is possible to spot out and compare local molecular environments in SAM-AuNPs exploiting atomistic machine-learning approaches, establishes ground rules to control them, and holds the potential for rational design of O-I nanomaterials instructed from data

Hysterectomy by transvaginal natural orifice transluminal endoscopic surgery: An Italian initial experience

BackgroundThe aim of this study is to evaluate the initial feasibility, safety, and outcomes of hysterectomy performed by transvaginal natural orifice transluminal endoscopic surgery (vNOTES) at three institutions in Italy.Materials and methodsAll women who underwent vNOTES hysterectomy ± salpingo-oophorectomy for benign indications at three tertiary referral medical centers between July 2019 and April 2021 were included in a retrospective analysis. All vNOTESs were performed with the use of Alexis® and Vpath Gel paths® (Applied Medical). Perioperative data were extracted from patient records. Patient satisfaction and dyspareunia were prospectively inquired about at 60 days and 6 months.ResultsForty-six patients underwent vNOTES in the study period. Indications for surgery included myomas ± metrorrhagia (52.2%), H-Sil/in situ cervical cancer (10.7%), adenomyosis ± metrorrhagia (8.7%), BRCA 1-2 mutations (6.5%), endometrial hyperplasia (6.5%), ovarian cyst + history of breast cancer (6.5%), metrorrhagia (6.5%), and hydatidiform mole (2.2%). The mean operation time was 91.1 (±32.6) minutes. The mean hemoglobin drop was 1.2 (±0.8). The mean visual analog scale at 24 h for post-operative pain was 3.3 (±1.8). Secondary to our limited experience with the surgical technique, we favor discharge only from day 1. The mean length of hospital stay was 2 (±1.4) days. Two conversions to conventional laparoscopy were reported (4.3%), due to an obliterated pouch of Douglas and a preoperative complication. Two post-operative complications were reported (4.3%). Overall, our data on peri- and post-operative outcomes are similar to those already published for vNOTES.ConclusionOur initial experience suggests that introducing vNOTES as an alternative to conventional surgery is feasible and may offer some advantages in selected women

Three-Dimensional Volumetric Changes in Severely Resorbed Alveolar Sockets After Ridge Augmentation with Bovine-Derived Xenograft and Resorbable Barrier: A Preliminary Study on CBCT Imaging

The primary aim of the study was to describe a novel technique to evaluate volumetric hard tissue dimensional changes after ridge augmentation procedures. The secondary aim was to apply this newly developed measuring method to compromised alveolar sockets grafted with a slowly resorbing biomaterial covered with a collagen membrane. Materials and Methods: Eleven patients (6 men and 5 women, mean age 52.7 ± 8.3 years) requiring extraction of one hopeless tooth for severe periodontitis in the maxillary anterior area were consecutively treated with a ridge augmentation procedure. All experimental sockets showed advanced buccal bone plate deficiency and were grafted with deproteinized bovine bone mineral with 10% collagen covered with a collagen membrane. Sockets healed by secondary intention. Three-dimensional volumetric alveolar bone changes were calculated by superimposing cone beam computed tomography scans obtained before and 12 months after the augmentation procedure. Results: After 12 months, the alveolar mineralized tissue filled 91.20% ± 7.96% of the maximum volume for regeneration. The augmentation procedure appeared not only to compensate for bone remodeling in most alveolar regions but also to repair a significant portion of the buccal wall. The most significant ridge width changes occurred 1 mm apical to the bone crest (2.33 ± 1.46 mm, P < .001). Conclusion: Within present limitations, this radiographic measuring methodology can be a useful tool to evaluate changes in socket volume. A ridge preservation technique performed with collagenated bovine bone and a collagen membrane was able to improve ridge shape and dimensions in compromised alveolar sockets

A novel image processing technique for three-dimensional volumetric analysis of severely resorbed alveolar sockets with cone beam computed tomography

The aim of this study was to present and validate a novel procedure for the quantitative volumetric assessment of extraction sockets that combines Cone-Beam Computed Tomography (CBCT) and image processing techniques

Endonasal Endoscopic Resection and Radiotherapy in Olfactory Neuroblastoma: our experience.

Background. Our aim was to evaluate the efficacy of a bimodal method of treatment consisting in endoscopic resection followed by radiotherapy in patients with olfactory neuroblastoma (ON). Methods. This is a retrospective review on 10 patients with ON treated at a tertiary referral center. All the patients were treated with endonasal endoscopic resection, and 1 refused postoperative radiotherapy. Results. No mortality was observed. Local tumor control was obtained in all the patients. Follow-up ranged from 15 to 79 months (median, 37 months). One patient developed a regional recurrence and for this was treated with bilateral, modified type III radical neck dissection plus radiotherapy on the neck. All patients regained a good quality of life after the treatment. Conclusions. This method of treatment causes minimal injury to the patients, reduces side effects, and improves the quality of life of those with olfactory neuroblastoma

Dual-Route Hydrogenation of the Graphene/Ni Interface

Nanostructured architectures based on graphene/metal interfaces might be efficiently exploited in hydrogen storage due to the attractive capability to provide adsorption sites both at the top side of graphene and at the metal substrate after intercalation. We combined in situ high-resolution X-ray photoelectron spectroscopy and scanning tunneling microscopy with theoretical calculations to determine the arrangement of hydrogen atoms at the graphene/Ni(111) interface at room temperature. Our results show that at low coverage H atoms predominantly adsorb as monomers and that chemisorption saturates when 3c25% of the surface is hydrogenated. In parallel, with a much lower rate, H atoms intercalate below graphene and bind to Ni surface sites. Intercalation progressively destabilizes the C-H bonds and triggers the release of the hydrogen chemisorbed on graphene. Valence band and near-edge absorption spectroscopy demonstrate that the graphene layer is fully lifted when the Ni surface is saturated with H. Thermal programmed desorption was used to determine the stability of the hydrogenated interface. Whereas the H atoms chemisorbed on graphene remain unperturbed over a wide temperature range, the intercalated phase abruptly desorbs 50-100 K above room temperature