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Objective: Postoperative radiotherapy (PORT) is indicated in almost two-thirds of patients treated with transoral robotic surgery (TORS) for head and neck tumors. The aim of this study was to quantify the toxicity profile of patients treated with PORT after TORS in oropharyngeal and supraglottic laryngeal cancer focusing on soft tissue necrosis (STN)., Methods: We retrospectively reviewed 28 patients. Acute and late toxicity were examined. Incidence and severity of STN were recorded., Results: No patient experienced acute grade 3 skin or mucosal toxicity; 1 patient had grade 3 dysphagia. At 12 months, no evaluated patient required enteral nutrition and 2 patients had tracheostomy. STN occurred in 4 (14%) patients: 3 out of 4 (75%) patients with STN had diabetes, whereas 6 out of 13 (25%) patients without STN had diabetes ( p = 0.05)., Conclusion: We found an acceptable toxicity profile of PORT performed after a TORS procedure. Diabetes mellitus might be a risk factor for STN.

Simple Summary: The present study has been suggested by the previous experience of our group showing that patients treated with conventional radiotherapy (named 3D conformal radiotherapy—3D-CRT) performed after conservative surgery (CS) for tumors of the supraglottic regions experienced a high rate of severe long-term toxicity. Therefore, we reported the toxicity profile of a similar cohort of patients treated with a high-precision radiotherapy technique (named intensity-modulated radiotherapy—IMRT). Moreover, to investigate the advantage of IMRT, we performed a comparison with a historical cohort treated with 3D-CRT. Results showed that patients treated with IMRT achieved a very low toxicity profile and comparison with 3D-CRT was in favor of IMRTs. Therefore, we believe that the results of the present study provide preliminary findings on the potential of IMRT in improving the toxicity profile of patients treated with surgical organ preservation strategies for laryngeal tumors. The aim of the present study was to investigate the role of intensity-modulated radiotherapy (IMRT) on the toxicity profile of patients treated with conservative surgery (CS) of the supraglottic (SG) region. Data on patients treated with CS and postoperative radiotherapy (PORT)-IMRT were prospectively collected. Results. In total, 20 patients were analyzed. Of these, six patients (35%) required the positioning of a temporary tracheostomy. The functional larynx preservation rate was 95%. Females had a higher risk of both endoscopic intervention and chondronecrosis, while the median age was significantly higher in patients requiring enteral nutrition. The incidence of long-term severe toxicities was lower in patients treated with IMRT than in the historical 3D-CRT cohort. Patients who had received PORT-IMRT achieved a lower rate of permanent laryngeal and swallowing dysfunctions. Overall, results from the comparison with the historical 3D-CRT cohort favor the IMRTs. [ABSTRACT FROM AUTHOR]

Objectives Atlas-based automatic segmentation (ABAS) addresses the challenges of accuracy and reliability in manual segmentation. We aim to evaluate the contribution of specific-purpose in ABAS of breast cancer (BC) patients with respect to generic-purpose libraries. Materials and methods One generic-purpose and 9 specific-purpose libraries, stratified according to type of surgery and size of thorax circumference, were obtained from the computed tomography of 200 BC patients. Keywords about contralateral breast volume and presence of breast expander/prostheses were recorded. ABAS was validated on 47 independent patients, considering manual segmentation from scratch as reference. Five ABAS datasets were obtained, testing single-ABAS and multi-ABAS with simultaneous truth and performance level estimation (STAPLE). Center of mass distance (CMD), average Hausdorff distance (AHD) and Dice similarity coefficient (DSC) between corresponding ABAS and manual structures were evaluated and statistically significant differences between different surgeries, structures and ABAS strategies were investigated. Results Statistically significant differences between patients who underwent different surgery were found, with superior results for conservative-surgery group, and between different structures were observed: ABAS of heart, lungs, kidneys and liver was satisfactory (median values: CMD<2 mm, DSC≥0.80, AHD<1.5 mm), whereas chest wall, breast and spinal cord obtained moderate performance (median values: 2 mm ≤ CMD<5 mm, 0.60 ≤ DSC<0.80, 1.5 mm ≤ AHD<4 mm) and esophagus, stomach, brachial plexus and supraclavicular nodes obtained poor performance (median CMD≥5 mm, DSC<0.60, AHD≥4 mm). The application of STAPLE algorithm generally yields higher performance and the use of keywords improves results for breast ABAS. Conclusion The homogeneity in the selection of atlases based on multiple anatomical and clinical features and the use of specific-purpose libraries can improve ABAS performance with respect to generic-purpose libraries. [ABSTRACT FROM AUTHOR]

• Contouring variability is a well-known issue in breast cancer radiotherapy. • Dosimetric impact of contouring variability of axillary nodes is scarcely investigated. • Variations in dosimetric coverage of axillary nodes emerged from a multicentric study. • The use of intensity modulated radiotherapy has amplified the dosimetric variations. • Consensus, quality assurance programme and automated outlining techniques are encouraged. To quantify the dosimetric impact of contouring variability of axillary lymph nodes (L2, L3, L4) in breast cancer (BC) locoregional radiotherapy (RT). 18 RT centres were asked to plan a locoregional treatment on their own planning target volume (single centre, SC-PTV) which was created by applying their institutional margins to the clinical target volume of the axillary nodes of three BC patients (P1, P2, P3) previously delineated (SC-CTV). The gold standard CTVs (GS-CTVs) of P1, P2 and P3 were developed by BC experts' consensus and validated with STAPLE algorithm. For each participating centre, the GS-PTV of each patient was created by applying the same margins as those used for the SC-CTV to SC-PTV expansion and replaced the SC-PTV in the treatment plan. Datasets were imported into MIM v6.1.7 [MIM Software Inc.], where dose-volume histograms (DVHs) were extracted and differences were analysed. 17/18 centres used intensity-modulated RT (IMRT). The CTV to PTV margins ranged from 0 to 10 mm (median 5 mm). No correlation was observed between GS-CTV coverage by 95% isodose and GS-PTV margins width. Doses delivered to 98% (D98) and 95% (D95) of GS-CTVs were significantly lower than those delivered to the SC-CTVs. No significant difference between SC-CTV and GS-CTV was observed in maximum dose (D2), always under 110%. Mean dose ≥99% of the SC-CTVs and GS-CTVs was satisfied in 84% and 50%, respectively. In less than one half of plans, GS-CTV V95% was above 90%. Breaking down the GS-CTV into the three nodal levels (L2, L3 and L4), L4 had the lowest probability to be covered by the 95% isodose. Overall, GS-CTV resulted worse coverage, especially for L4. IMRT was largely used and CTV-to-PTV margins did not compensate for contouring issues. The results highlighted the need for delineation training and standardization. [ABSTRACT FROM AUTHOR]

Abstract: When local recurrences arise within an irradiated region involving metastatic spinal cord compression, the dose limit to the spinal cord reduces the chance to re-treat the patient by 3D-conformational RT technique. The possibility of using volumetric modulated arc RT by RapidArc was evaluated for dose sparing at spinal cord level and preserving target coverage. A clinically satisfactory PTV coverage and dose sparing to the spinal cord were obtained. An upcoming trial on patients will provide clinical outcomes. [Copyright &y& Elsevier]

Purpose: A planning study was performed comparing volumetric modulated arcs, RapidArc (RA), fixed beam IMRT (IM), and conformal radiotherapy (CRT) with multiple static fields or short conformal arcs in a series of patients treated with hypofractionated stereotactic body radiation therapy (SBRT) for solitary or oligo-metastases from different tumors to abdominal lymph nodes. Methods and Materials: Fourteen patients were included in the study. Dose prescription was set to 45 Gy (mean dose to clinical target volume [CTV]) in six fractions of 7.5 Gy. Objectives for CTV and planning target volume (PTV) were as follows: Dosemin >95%, Dosemax <107%. For organs at risk the following objectives were used: Maximum dose to spine <18 Gy; V15Gy <35% for both kidneys, V36Gy <1% for duodenum, V36Gy <3% for stomach and small bowel, V15Gy <(total liver volume − 700 cm3) for liver. Dose–volume histograms were evaluated to assess plan quality. Results: Planning objectives on CTV and PTV were achieved by all techniques. Use of RA improved PTV coverage (V95% = 90.2% ± 5.2% for RA compared with 82.5% ± 9.6% and 84.5% ± 8.2% for CRT and IM, respectively). Most planning objectives for organs at risk were met by all techniques except for the duodenum, small bowel, and stomach, in which the CRT plans exceeded the dose/volume constraints in some patients. The MU/fraction values were as follows: 2186 ± 211 for RA, 2583 ± 699 for IM, and 1554 ± 153 for CRT. Effective treatment time resulted as follows: 3.7 ± 0.4 min for RA, 10.6 ± 1.2 min for IM, and 6.3 ± 0.5 min for CRT. Conclusions: Delivery of SBRT by RA showed improvements in conformal avoidance with respect to standard conformal irradiation. Delivery parameters confirmed logistical advantages of RA, particularly compared with IM. [Copyright &y& Elsevier]