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Halyomorpha halys (Heteroptera: Pentatomidae) is an insect pest native to Asia that has spread over the last two decades to most of the North America, parts of South America, Europe and North Africa. Its impact is significant as it can feed on more than 300 host plants, rendering affected fruits and vegetable crops unsellable or of lower quality. Various chemical and biological methods have been used to control this pest, with varying degrees of success. The sterile insect technique (SIT) is a pest control method involving the sterilization of insects via ionizing radiation and their subsequent mass release into the field. In the present contribution, the spermiogenesis of H. halys was studied from an ultrastructural point of view in both irradiated and non-irradiated adult males. In both cases, we observed ultrastructural characteristics typical of hemipteran sperm cells: bridges connecting the mitochondrial derivatives and the axonemal microtubules, the absence of accessory bodies, and the presence of two or three crystalline inclusions within the mitochondrial derivatives, an acrosome composed of tightly packed tubules, and an atypical, plaque-shaped microtubular organizing center (MTOC) in the centriolar region. Moreover, in the same region, we seldom observed the presence of two centrioles in the spermatids, one of which disappeared at a later stage of maturation. This feature is a novelty for insect spermiogenesis. The cysts of irradiated adults were not all uniformly affected by the radiation. However, irradiated cysts sometimes exhibited a general disorganization of sperm arrangement, incomplete divisions of sperm cells resulting in multiple copies of the same organelle within the same cell, failure to reabsorb the cytoplasm, and the lack of axonemes. Finally, rod-shaped viruses or virus-like particles were observed in vasa deferentia independently of irradiation.
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The brown marmorated stink bug, Halyomorpha halys, is a pentatomid bug of Eastern Asian origin that became an economically relevant pest in the Eurasian and American continents. Management of this species is limited to use of chemical insecticides: an inefficient method due to the strong adaptability of the target pest. The sterile insect technique (SIT) is potentially a valid tactic in the search for nontoxic alternatives. In this work, we investigated the suitability of mass-trapped overwintering males, collected during the aggregation phase before the winter diapause, for their release as competitive sterile males in an SIT programme. Differently from previous studies, irradiation was applied with a linear accelerator device that produced high-energy photons. Following a similar scientific protocol with newly emerged irradiated males, the effects of X-ray irradiation on physiological parameters (longevity, fecundity and fertility) were assessed. In addition, behavioural bioassays were carried out in no-choice conditions to evaluate if irradiation interferes with mating processes. The results are very encouraging; the effects of the irradiation at 32 Gy did not differ from the controls in the longevity or fecundity of the exposed overwintering adults. The hatching rate of the eggs laid by the fertile females that had mated with the irradiated males was less than 5%. The results of behavioural bioassays showed that the irradiation did not cause a significant impact on the quality of the sterile males. More research is warranted to evaluate the mating competitiveness of sterile males in semi-field and field conditions.
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PURPOSE: Comparative outcome data after intraoperative radiation therapy and whole breast irradiation (WBI) for breast cancer at >10 years median follow-up are rare. We present a mature, single-institution, matched-pair comparison reporting survival and relapse rates in patients treated with either modality. METHODS AND MATERIALS: Complete data sets for 258 intraoperative electron radiation therapy (IOERT) patients treated between 2000 and 2010 were matched with 258 patients postoperatively treated with WBI by age/histology/tumor size, grading/lymph-node-status/hormone receptors/type of adjuvant therapy/surgical margins, and treatment date. Relapse at surgical intervention site was classified as true local recurrence (LR). All recurrences in the treated breast (any quadrant) were classified as ipsilateral recurrence (IR). RESULTS: Median follow-up was 157 months (12-251) for the IOERT group and 154 months (31-246) for the WBI group. Cumulative incidence of IR at 5, 10, and 15 years was 2.4%, 7.9%, and 12.7% for IOERT and 1.2%, 4.1%, and 5.0% for WBI (P = .02). Cumulative incidence of LR at 5, 10, and 15 years was 1.6%, 5.1%, and 8.3% for IOERT and 0.4%, 2.1%, and 2.5% for WBI (P = .02). No differences in overall survival, disease-free survival, second cancer incidence, or cardiac events were recorded in either treatment group. Outcome was better in the accelerated partial breast irradiation (APBI)-suitable group than in the APBI-unsuitable group (2009 criteria) (cumulative incidence of IR at 5, 10, and 15 years was 0% vs 7.3%, 6.1% vs 13.3%, and 7.3% vs 19.9% for IOERT and 0% vs 1.8%, 2.0% vs 3.9%, and 3.1% vs 3.9% for WBI) and in the revised APBI-suitable group than in the APBI-cautionary group (2017 criteria) (cumulative incidence of IR at 5, 10, and 15 years was 1.1% vs 6.4%, 6.2% vs 13.3%, and 7.8% vs 27.5% for IOERT and 1.7% vs 0%, 4.1% vs 4.4%, and 5.4% vs 4.4% for WBI). CONCLUSIONS: The IR and LR rate were higher after IOERT than after WBI for the American Society for Radiation Oncology suitable patient group, although without reaching statistical significance. Thus, IOERT could be an alternative to WBI upon stringent patient selection, but patients should be counseled carefully about the potential for increased IR rate with IOERT. Second cancer incidence and cardiac events did not differ between IOERT and WBI.
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Braquiterapia , Neoplasias da Mama , Doenças Cardiovasculares , Segunda Neoplasia Primária , Humanos , Feminino , Intervalo Livre de Progressão , Elétrons , Segunda Neoplasia Primária/cirurgia , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Mastectomia Segmentar/métodos , Recidiva , Recidiva Local de Neoplasia/cirurgia , Braquiterapia/métodosRESUMO
Current follow-up policies for early breast cancer aim to detect loco-regional recurrences and manage treatment-related adverse effects. Their "one size fits all" approach does not take into account differences in subtypes at initial diagnosis, individual prognosis and treatments received. They are derived from clinical trials conducted when early detection means - other than mammography - and treatment options were limited. Herein, we address the arguments for re-evaluating current breast cancer follow-up strategies starting from recent advances in breast cancer local and systemic treatments and discussing individual risk of recurrence prediction models, time-adapted imaging and biomarker assessment for disease diagnostic anticipation. This change in perspective would transform breast cancer follow-up into an integrated, multidisciplinary team medical practice. Hence we discuss the important role of patient-centered approaches, but also of general practitioners and other health professionals, in the final promotion of personalized surveillance programs and patient education.
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Neoplasias da Mama , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/terapia , Feminino , Seguimentos , Humanos , Mamografia , Recidiva Local de Neoplasia/diagnósticoRESUMO
PURPOSE: A radiomics features classifier was implemented to evaluate segmentation quality of heart structures. A robust feature set sensitive to incorrect contouring would provide an ideal quantitative index to drive autocontouring optimization. METHODS: Twenty-five cardiac sub-structures were contoured as regions of interest in 36 CTs. Radiomic features were extracted from manually-contoured (MC) and Hierarchical-Clustering automatic-contouring (AC) structures. A robust feature-set was identified from correctly contoured CT datasets. Features variation was analyzed over a MC/AC dataset. A supervised-learning approach was used to train an Artificial-Intelligence (AI) classifier; incorrect contouring cases were generated from the gold-standard MC datasets with translations, expansions and contractions. ROC curves and confusion matrices were used to evaluate the AI-classifier performance. RESULTS: Twenty radiomics features, were found to be robust across structures, showing a good/excellent intra-class correlation coefficient (ICC) index comparing MC/AC. A significant correlation was obtained with quantitative indexes (Dice-Index, Hausdorff-distance). The trained AI-classifier detected correct contours (CC) and not correct contours (NCC) with an accuracy of 82.6% and AUC of 0.91. True positive rate (TPR) was 85.1% and 81.3% for CC and NCC. Detection of NCC at this point of the development still depended strongly on degree of contouring imperfection. CONCLUSIONS: A set of radiomics features, robust on "gold-standard" contour and sensitive to incorrect contouring was identified and implemented in an AI-workflow to quantify segmentation accuracy. This workflow permits an automatic assessment of segmentation quality and may accelerate expansion of an existing autocontouring atlas database as well as improve dosimetric analyses of large treatment plan databases.
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Processamento de Imagem Assistida por Computador , Planejamento da Radioterapia Assistida por Computador , Coração/diagnóstico por imagem , Radiometria , Tomografia Computadorizada por Raios XRESUMO
[This corrects the article DOI: 10.3389/fonc.2021.744956.].
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INTRODUCTION: For unresectable stage III non-small cell lung cancer (NSCLC), the standard therapy consists of chemoradiotherapy (CRT) followed by durvalumab maintenance for responding patients. The present study reports on the safety and outcome of durvalumab use after CRT in a real-world, multicenter, retrospective cohort. METHODS: Two hundred thirty-eight patients have been included. We collected data on systemic therapy, radiation therapy, the timing between CRT and durvalumab, number of durvalumab cycles, reasons for non-starting or discontinuation, incidence and grade of adverse events (AEs), and progression-free survival (PFS) and overall survival (OS). RESULTS: One hundred fifty-five patients out of 238 (65.1%) received at least one durvalumab dose: 91 (58.7%) after concomitant CRT (cCRT) and 64 (41.3%) after sequential CRT (sCRT). Programmed-death ligand 1 (PD-L1) status was unknown in 7/155 (4.5%), negative in 14 (9.1%), and positive ≥1% in 134/155 (86.4%). The main reasons for non-starting durvalumab were progression (10.1%), PD-L1 negativity (7.5%), and lung toxicity (4.6%). Median follow-up time was 14 months (range 229); 1-year PFS and OS were 65.5% (95%CI: 57.6-74.4) and 87.9% (95%CI: 82.26.6-93.9), respectively. No significant differences in PFS or OS were detected for cCRT vs. sCRT, but the median PFS was 13.5 months for sCRT vs. 23 months for cCRT. Potentially immune-related AEs were recorded in 76/155 patients (49.0%). Pneumonitis was the most frequent, leading to discontinuation in 11/155 patients (7.1%). CONCLUSIONS: Durvalumab maintenenace after concurrent or sequential chemoradiation for unresectable, stage III NSCLC showed very promising short-term survival results in a large, multicenter, restrospective, real-world study. Durvalumab was the first drug obtaining a survival benefit over CRT within the past two decades, and the present study contributes to validating its use in clinical practice.
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PURPOSE: Segmentation of cardiac sub-structures for dosimetric analyses is usually performed manually in time-consuming procedure. Automatic segmentation may facilitate large-scale retrospective analysis and adaptive radiotherapy. Various approaches, among them Hierarchical Clustering, were applied to improve performance of atlas-based segmentation (ABS). METHODS: Training dataset of ABS consisted of 36 manually contoured CT-scans. Twenty-five cardiac sub-structures were contoured as regions of interest (ROIs). Five auto-segmentation methods were compared: simultaneous automatic contouring of all 25 ROIs (Method-1); automatic contouring of all 25 ROIs using lungs as anatomical barriers (Method-2); automatic contouring of a single ROI for each contouring cycle (Method-3); hierarchical cluster-based automatic contouring (Method-4); simultaneous truth and performance level estimation (STAPLE). Results were evaluated on 10 patients. Dice similarity coefficient (DSC), average Hausdorff distance (AHD), volume comparison and physician score were used as validation metrics. RESULTS: Atlas performance improved increasing number of atlases. Among the five ABS methods, Hierarchical Clustering workflow showed a significant improvement maintaining a clinically acceptable time for contouring. Physician scoring was acceptable for 70% of the ROI automatically contoured. Inter-observer evaluation showed that contours obtained by Hierarchical Clustering method are statistically comparable with them obtained by a second, independent, expert contourer considering DSC. Considering AHD, distance from the gold standard is lower for ROIs segmented by ABS. CONCLUSIONS: Hierarchical clustering resulted in best ABS results for the primarily investigated platforms and compared favorably to a second benchmark system. Auto-contouring of smaller structures, being in range of variation between manual contourers, may be ideal for large-scale retrospective dosimetric analysis.
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Neoplasias da Mama/diagnóstico por imagem , Coração/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Radiometria/métodos , Análise de Variância , Análise por Conglomerados , Feminino , Humanos , Imageamento Tridimensional , Pulmão/diagnóstico por imagem , Variações Dependentes do Observador , Reconhecimento Automatizado de Padrão , Planejamento da Radioterapia Assistida por Computador/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Tomografia Computadorizada por Raios XRESUMO
PURPOSE: To estimate the dosimetric impact of residual setup errors on parotid sparing in head-and-neck (H&N) intensity-modulated treatments and to evaluate the effect of employing an PRV (planning organ-at-risk volume) margin for the parotid gland. PATIENTS AND METHODS: Ten patients treated for H&N cancer were considered. A nine-beam intensity-modulated radiotherapy (IMRT) was planned for each patient. A second optimization was performed prescribing dose constraint to the PRV of the parotid gland. Systematic setup errors of 2 mm, 3 mm, and 5 mm were simulated. The dose-volume histograms of the shifted and reference plans were compared with regard to mean parotid gland dose (MPD), normal-tissue complication probability (NTCP), and coverage of the clinical target volume (V95% and equivalent uniform dose [EUD]); the sensitivity of parotid sparing on setup error was evaluated with a probability-based approach. RESULTS: MPD increased by 3.4%/mm and 3.0%/mm for displacements in the craniocaudal and lateral direction and by 0.7%/ mm for displacements in the anterior-posterior direction. The probability to irradiate the parotid with a mean dose > 30 Gy was > 50%, for setup errors in cranial and lateral direction and < 10% in the anterior-posterior direction. The addition of a PRV margin improved parotid sparing, with a relative reduction in NTCP of 14%. The PRV margin compensates for setup errors of 3 mm and 5 mm (MPD < or = 30 Gy in 87% and 60% of cases), without affecting clinical target volume coverage (V95% and EUD variations < 1% and < 1 Gy). CONCLUSION: The parotid gland is more sensitive to craniocaudal and lateral displacements. A setup error of 2 mm guarantees an MPD < or = 30 Gy in most cases, without adding a PRV margin. If greater displacements are expected/accepted, an adequate PRV margin could be used to meet the clinical parotid gland constraint of 30 Gy, without affecting target volume coverage.
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Processamento de Imagem Assistida por Computador/métodos , Neoplasias Otorrinolaringológicas/radioterapia , Glândula Parótida/efeitos da radiação , Lesões por Radiação/etiologia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Tomografia Computadorizada por Raios X/métodos , Simulação por Computador , Humanos , Metástase Linfática/radioterapia , Neoplasias Otorrinolaringológicas/diagnóstico por imagem , Probabilidade , Doses de Radiação , Lesões por Radiação/prevenção & controle , Medição de Risco , Sensibilidade e EspecificidadeRESUMO
AIMS AND BACKGROUND: Major salivary gland cancers are rare, with many histologic types and subtypes. The low incidence and heterogeneity of primary parotid carcinomas makes their outcome difficult to evaluate. Treatment remains primarily surgical, but optimal therapeutic regimens have yet to be fully realized. The present study reviews the experience of three Italian institutions in the treatment of primary parotid carcinomas in order to describe the clinicopathological presentation and treatment options with emphasis on radiotherapy and to analyze the factors influencing survival. METHODS AND STUDY DESIGN: The records of 110 patients with primary parotid neoplastic lesions treated at three Italian institutions from 1993 to 2004 were retrospectively reviewed. Six patients were excluded from the study: 3 received surgery alone and 3 were not assessable, for a total of 104 assessable patients. Acute and late toxicity of radiotherapy was quantified following the recommendations of the RTOG/EORTC. Survival was analyzed by the actuarial Kaplan-Meier product-limit method. The influence of selected factors on 10-year disease-specific survival was analyzed. RESULTS: The 104 assessable patients were treated as follows: 11 patients received radiotherapy as their only treatment (3 with a palliative purpose) and 93 had postoperative radiotherapy. Thirty-two patients underwent neck dissection: neck lymph node metastases were found in all them. Their mean age was 60 years (range, 14-92). According to the UICC/2002 TNM Classification, 8 patients were stage I, 19 stage II, 34 stage III, 25 stage IVA, 5 stage IVB, 3 recurrent and 10 not assessable (Tx). The most frequent histologies were adenoid cystic carcinoma (n = 16), mucoepidermoid carcinoma (n = 15), and acinic cell carcinoma (n = 15). Twenty-three patients had recurrences: 10 had local recurrences, 3 neck recurrences, 9 distant metastases, and 1 patient had both local recurrence and distant metastases. No factors were observed that would negatively influence the prognosis. Actuarial 10-year disease-specific survival was 71% and actuarial 10-year local control 82%. CONCLUSIONS: The treatment of salivary gland malignancies remains primarily surgical. Our study confirms the results of the literature with surgery and adjunctive radiotherapy in patients with advanced-stage disease. No variables were observed to influence the prognosis.
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Neoplasias Parotídeas/radioterapia , Neoplasias Parotídeas/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Parotídeas/patologia , Prognóstico , Estudos Retrospectivos , Adulto JovemRESUMO
BACKGROUND: The aim of this review is the critical appraisal of the current use of volumetric modulated arc therapy for the radiation therapy management of breast cancer. Both clinical and treatment planning studies were investigated. MATERIAL AND METHODS: A Pubmed/MEDLINE search of the National Library of Medicine was performed to identify VMAT and breast related articles. After a first order rejection of the irrelevant findings, the remaining articles were grouped according to two main categories: clinical vs. planning studies and to some sub-categories (pointing to significant technical features). Main areas of application, dosimetric and clinical findings as well as areas of innovations were defined. RESULTS: A total of 131 articles were identified and of these, 67 passed a first order selection. Six studies reported clinical results while 61 treatment dealed with treatment planning investigations. Among the innovation lines, the use of high intensity photon beams (flattening filter free), altered fractionation schemes (simultaneous integrated boost, accelerated partial breast irradiation, single fraction), prone positioning and modification of standard VMAT (use of dynamic trajectories or hybrid VMAT methods) resulted among the main relevant fields of interest. Approximately 10% of the publications reported upon respiratory gating in conjunction with VMAT. CONCLUSIONS: The role of VMAT in the radiation treatment of breast cancer seems to be consolidated in the in-silico arena while still limited evidence and only one phase II trial appeared in literature from the clinical viewpoint. More clinical reports are needed to fully proove the expected dosimetric benefits demonstrated in the planning investigations.
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Neoplasias da Mama/radioterapia , Radioterapia de Intensidade Modulada/métodos , Gerenciamento Clínico , Feminino , Humanos , Dosagem RadioterapêuticaRESUMO
BACKGROUND: The purpose of this study was to evaluate the use of raster-scanned intensity-controlled carbon ion therapy (ICCT) in the treatment of mucosal melanoma of the paranasal sinus. METHODS: Patients received combined intensity-modulated radiotherapy (IMRT) plus carbon ion (C12). Records of 18 consecutive patients treated between 2009 and 2013 were analyzed retrospectively regarding toxicity (Common Terminology Criteria for Adverse Events, version 4), treatment response (Response Evaluation Criteria in Solid Tumors [RECIST]), and control/survival rates. RESULTS: Most patients had advanced disease (T4, 94%; gross residual disease, 78%). Median dose was 74 GyE (median boost volume = 157 mL). C12 treatments were planned as ICCT, no concurrent chemotherapy was administered. Grade III or higher late toxicity was not observed. Overall survival (OS), progression-free survival (PFS), and locoregional control at 3 years were 16.2%, 0%, and 58.3%, respectively (median follow-up, 18 months). Resection status did not impact locoregional control or survival rates. CONCLUSION: ICCT results in promising locoregional control at mild toxicity. OS is poor because of the occurrence of distant metastases; therefore, addition of systemic components to primary treatment should be investigated. © 2015 Wiley Periodicals, Head Neck 38: E1445-E1451, 2016.
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Radioterapia com Íons Pesados , Melanoma/radioterapia , Neoplasias Nasais/radioterapia , Radioterapia de Intensidade Modulada , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Humanos , Pessoa de Meia-Idade , Mucosa Nasal/patologia , Dosagem Radioterapêutica , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
OBJECTIVE: The aim of this study was to evaluate the oncologic outcomes after a selective neck dissection (SND), both in elective and therapeutic settings, with particular regard to regional recurrence rate. METHODS: Retrospective analysis of 827 patients with head and neck primary tumors submitted to SND from 1999 to 2011 in two large hospital centers of northern Italy. RESULTS: A total of 40 neck recurrences were found in the whole series, with the same incidence after primary or salvage surgery (4.4% and 5.2%, respectively), but only 22 neck recurrences occurred in the same side of the dissected neck (3.0%). Factors predicting an increase of ipsilateral neck relapse were pathologically positive nodes, number of positive nodes, and nodal ratio (ratio between positive nodes and total nodal removed), but the risk of regional relapse did not exceed 5.0% in any subgroups. A total of 320 patients (39%) had postoperative radiotherapy (52.0% and 22.0% after primary and salvage surgery, respectively). Considering the primary surgery group alone, postoperative radiotherapy produced only a light reduction of homolateral neck recurrence rate in patients with pathological positive nodes (2.4% vs. 5.0%), but it impacted significantly disease-specific survival, both in pathological classification of nodes (pN)1 and pN2-3 patients. CONCLUSION: The SND can be considered a safe and sound procedure both in primary surgery and in salvage setting. Postoperative radiotherapy adds minor advantage to regional control only in node-positive patients but may impact survival. LEVEL OF EVIDENCE: 4.
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Carcinoma de Células Escamosas/secundário , Procedimentos Cirúrgicos Eletivos/métodos , Neoplasias de Cabeça e Pescoço/secundário , Esvaziamento Cervical/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/cirurgia , Feminino , Seguimentos , Neoplasias de Cabeça e Pescoço/epidemiologia , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Itália/epidemiologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Resultado do Tratamento , Adulto JovemRESUMO
PURPOSE: To investigate the feasibility of applying exclusive intraoperative radiation therapy (IORT) after conservative surgery in limited-stage breast carcinoma and to evaluate late effects and cosmetic results after this new conservative treatment. PATIENTS AND METHODS: From October 2000 to November 2002, 47 consecutive patients with unifocal breast carcinoma up to a diameter of 2 cm received conservative surgery followed by IORT with electrons as the sole adjuvant local therapy. Three different dose levels were used: 20 Gy (seven patients), 22 Gy (20 patients), and 24 Gy (20 patients). Patients were evaluated using RTOG/EORTC scale to assess the incidence of late complications. During follow-up, a radiologic assessment with mammography and sonography was periodically performed and any breast-imaging alterations were reported. RESULTS: After a follow-up ranging from 36 to 63 months (median, 48 months), 15 patients developed breast fibrosis (grade 2 in 14 patients, grade 3 in one patient), two patients presented with grade 3 skin changes, one patient developed a clinically relevant fat necrosis, and one patient showed breast edema and pain. Two patients developed contralateral breast cancer and one distant metastases; no local relapses occurred. Asymptomatic findings of fat necrosis were observed at mammography in twelve patients (25.5%), while an hypoechoic area was revealed by sonography in ten patients (21.5%). In four patients (8%), mammographic and sonographic findings suggested malignant lesions and required a rebiopsy to confirm the benign nature of the lesion. CONCLUSION: IORT in breast carcinoma is still an experimental treatment option for select patients with breast cancer and its application should be restricted to prospective trials. Although preliminary data on local control are encouraging, a longer follow-up is needed to confirm the efficacy of IORT in breast cancer and to exclude that severe late complications compromise the cosmetic results or modify the radiologic breast appearance during follow-up increasing the need for additional investigations.