[Dosimetric and toxicity comparison of IMRT and 3D-CRT of non-small cell lung cancer]. / Comparaison dosimétrique et de la toxicité de la radiothérapie conformationnelle avec modulation d'intensité et de la radiothérapie conformationnelle tridimensionnelle des carcinomes bronchiques non à petites cellules.

PURPOSE: Although three-dimensional conformal radiotherapy (3D-CRT) remains the gold standard as a curative treatment for NSCLC when surgery is not possible, intensity modulated radiotherapy (IMRT) is increasingly used routinely. The purpose of this study was to assess the clinical (immediate toxicities) and dosimetric impact of IMRT compared to 3D-CRT in the treatment of locally advanced (stages IIIA to IIIC) non-small cell lung cancer (NSCLC) treated with concomitant radiochemotherapy, while IMRT in lung cancer was implemented in the radiotherapy department of the Jean-Perrin Center. PATIENTS AND METHODS: Between March 2015 and October 2019, 64 patients treated with concomitant radiochemotherapy were retrospectively included. Thirty-two received 3D-CRT and 32 IMRT. The radiotherapy prescription was 66Gy in 33 fractions of 2Gy. RESULTS: IMRT has improved coverage of target volumes (V95 increased by 14.81% in IMRT; P<0.001) without increasing doses to OARs and reducing dysphagia (RR=0.67; P=0.027). Low doses to the lung were not significantly increased in IMRT (pulmonary V5 increased by 7.46% in IMRT). CONCLUSION: Intensity modulated radiotherapy, compared with the standard RC3D technique, improve the coverage of target volumes without increasing the dose to the OARs. It also improves the immediate tolerance of the treatment by reducing the number of dysphagia.

Daily waiting and treatment times at an advanced radiation oncology setup: A 4-year audit of consecutive patients from single institution.

PURPOSE: We present our data for every single fraction for every patient treated at our center for the past 4 years, analyzing the waiting and treatment times. MATERIALS AND METHODS: Between January 2014 and February 2018, all patients and their corresponding recorded measurements of waiting time and machine treatment time were analyzed. Times recorded included actual arrival time, designated arrival time, linac entry time, and last beam treatment time. The complete waiting time information was divided into two categories (1) first day treatments and (2) subsequent day treatments. SPSS version 18 was used for statistical calculations, correlations, and assessing significance. RESULTS: First day treatments - of 1982 patients following treatments were carried out; 1557 volumetric-modulated arc therapy (78.6%), 88 three-dimensional conformal radiotherapy (RT) (4.4%), 14 electron (0.7%), 10 intensity-modulated RT (0.5%), 264 stereotactic irradiation (13.3%), 17 stereotactic body RT (0.7%), and 32 total body irradiation (1.6%). The mean (± standard deviation) times for early/late time, total spent time (TST), wait time gross (WTG), and wait time net (WTN) were 11.0 ± 49.6 min, 74.7 ± 44.8 min, 47.46 ± 43.9 min, and 24.1 ± 44.4 min, respectively. Subsequent day treatments - a total of 34,438 sessions of treatment delivery were recorded. Overall average WTG was 37.4 ± 32.7 min. Overall WTN was 12.1 ± 62.7 min. Overall mean total spent time (TST) was 52.4 ± 33.0 min, overall mean setup and treatment time was 15.1 ± 10.9 min. CONCLUSION: We have presented our results of patient-related times during RT. Our study covers the daily waiting times before RT as well as the actual treatment times during modern-day RT. This consecutive patient data from a large series shall be an important resource tool for future planners and policymakers.

National variation in the delivery of radiation oncology procedures in the non-facility-based setting.

PURPOSE: Though utilization of medical procedures has been shown to vary considerably across the United States, similar efforts to characterize variation in the delivery of radiation therapy (RT) procedures have not been forthcoming. Our aim was to characterize variation in the delivery of common RT procedures in the Medicare population. We hypothesized that delivery would vary significantly based on provider characteristics. METHODS: The Centers for Medicare and Medicaid Services (CMS) Physician and Other Supplier Public Use File was linked to the CMS Physician Compare (PC) database by physician NPI to identify and sum all treatment delivery charges submitted by individual radiation oncologists in the non-facility-based (NFB) setting in 2016. Multivariable logistic regression analysis was carried out to determine provider characteristics (gender, practice rurality, practice region, and years since graduation) that predicted for the delivery of 3D conformal RT (3DCRT), intensity modulated RT (IMRT), stereotactic body RT (SBRT), stereotactic radiosurgery (SRS), low dose rate (LDR) brachytherapy, and high dose rate (HDR) brachytherapy delivery in the Medicare patient population. The overall significance of categorical variables in the multivariable logistic regression model was assessed by the likelihood ratio test (LRT). RESULTS: In total, 1,802 physicians from the NFB practice setting were analyzed. Male gender predicted for greater LDR brachytherapy delivery (OR 8.19, 95% CI 2.58-26.05, p < 0.001), but not greater delivery of other technologies. Metropolitan practice was the only predictor for greater HDR brachytherapy utilization (OR 12.95, 95% CI 1.81-92.60, p = 0.01). Practice region was predictive of the delivery of 3DCRT, SRS and SBRT (p < 0.01, p < 0.001, and p < 0.001, respectively). With the Northeast as the reference region, 3DCRT was more likely to be delivered by providers in the South (OR 1.33, 95% CI 1.09-1.62, p < 0.01) and the West (OR 1.38, 95% CI 1.11-1.71, p < 0.01). At the same time, SRS use was less likely in the Midwest (OR 0.71, 95% CI 0.55-0.91, p < 0.01), South (OR 0.49, 95% CI 0.40-0.61, p < 0.001), and West (OR 0.43, 95% CI 0.34-0.55, p < 0.001). SBRT, on the other hand, was more commonly utilized in the Midwest (OR 2.63, 95% CI 1.13-6.13, p = 0.03), South (OR 3.44, 95% CI 1.58-7.49, p < 0.01), and West (OR 4.87, 95% CI 2.21-10.72, p < 0.001). HDR brachytherapy use was also more likely in the Midwest (OR 1.97, 95% CI 1.11-3.49, p = 0.02) and West (OR 1.87, 95% CI 1.08-3.24, p = 0.03). While the degree held by the billing physician did not predict for delivery of a given procedure, greater years since graduation was related to decreased likelihood of SBRT use (OR 0.98, 95% CI 0.96-0.99, p < 0.001) and increased likelihood of LDR brachytherapy use (OR 1.02, 95% CI 1.00-1.04, p = 0.02). CONCLUSIONS: Substantial geographic variation in the use of specific RT technologies was identified. The degree to which this variation reflects effective care, preference-sensitive care, or supply-sensitive care warrants further investigation.

Implications of Radiotherapy Utilization in Korea from 2010 to 2019.

BACKGROUND: This study was to assess the rate of radiotherapy (RT) utilization according to the modality in South Korea to identify the implications of contemporary RT patterns. METHODS: We collected information from claims and reimbursement records of the National Health Insurance Service from 2010 to 2019. We classified the location of each institution as capital (Seoul, Incheon, and Gyeonggi-do) and non-capital areas. RESULTS: The rate of RT utilization in total cancer patients nationwide was 24.5% in 2010, which consistently has increased to 36.1% in 2019 (annual increase estimate [AIE], 4.5%). There was an abrupt increase in patients receiving intensity-modulated RT (IMRT), with an AIE of 33.5%, and a steady decline in patients receiving three-dimensional conformal RT (3DCRT), with an AIE of -7.1%. The commonest RT modality was IMRT (44.5%), followed by 3DCRT and stereotactic RT (SRT) (37.2% and 13.5%) in 2019. An increasing trend of advanced RT (such as IMRT and SRT) utilization was observed regardless of the region, although the AIE in the capital areas was slightly higher than that in non-capital areas. CONCLUSION: The utilization of overall RT application and especially of advanced modalities remarkably increased from 2010 to 2019. We also found gaps in their AIEs between capital and non-capital areas. We should ensure that advanced RT is accessible to all cancer patients across South Korea.

Can we define any marker associated with brain failure in patients with locally advanced non-small cell lung cancer?

PURPOSE: To define the factors which may be related to brain metastasis (BM) in patients with locally advanced non-small cell lung cancer (LA-NSCLC) who developed brain metastases after definitive treatment. PATIENTS AND METHODS: A total of 208 patients with LA-NSCLC, without BM who received definitive radiotherapy (RT) or RT+chemotherapy (CT) between January 2005 and January 2016 were evaluated retrospectively. Platelet, neutrophil, lymphocyte counts, LDH, CRP, Hb levels, neutrophil-to-lymphocyte radio (NLR), platelet-to-lymphocyte radio (PLR), advanced lung cancer inflammation index (ALI) and FDG-PET/CT parameters (SUVmax of the primary tumor and mediastinal lymph nodes), and patient characteristics were evaluated for brain metastasis free survival (BMFS). RESULTS: Median follow-up duration was 25 months (range: 3-130months). Cut-off values for platelet, NLR, PLR, LDH, CRP, and Hb were 290×103/µL, 2.6, 198, 468 IU/L, 2.5mg/dL, and 11.5g/dl. We defined each parameter as low or high according to the cut-off values. 56 patients (26.9%) developed brain metastases during follow-up. In univariate analysis, high NLR (P=0.001), PLR (P=0.037), LDH (P=0.028), CRP (P=0.002) values, value ≥7.5 for lymph nodes (P=0.005) and low ALI value (P=0.002) were poor prognostic factors for BMFS. In multivariate analysis, high NLR (P=0.022), PLR (P=0.017), CRP (P=0.006), stage ≥IIIB disease (P<0.001), multi-stational N2 disease (P=0.036), adenocarcinoma histology (P<0.001) and SUVmax value ≥7.5 (P=0.035) were poor prognostic factors for BMFS. CONCLUSIONS: High NLR, PLR, LDH, CRP values, SUVmax values for lymph nodes, and low ALI which indicates high tumor burden were additional prognostic factors besides stage, histology, and lymph node status.

Quality of Life: A Prospective Randomized Trial of Palliative Volumetric Arc Therapy Versus 3-Dimensional Conventional Radiation Therapy.

PURPOSE: Volumetric arc therapy (VMAT) is a radiation therapy (RT) technique that spares normal tissues from high and intermediate RT doses but increases the volume of tissues receiving low doses of RT compared with 3-dimensional conformal RT (3DCRT). We hypothesized that palliative VMAT would reduce the detriment to patient quality of life (QOL) compared with palliative 3DCRT. METHODS AND MATERIALS: This phase 2 trial randomized patients to palliative RT using VMAT or 3DCRT to 1 painful site of metastatic disease in the trunk. Treating physicians could choose 8 Gy in 1 fraction or 20 Gy in 5 fractions to stratify randomization. The primary endpoint was the change in European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Version 3.0 (EORTC QLQ-C30) global health status QOL subscale at 1 week after RT. Repeated measures analysis of variance was used to assess the relationship of patient QOL over time with other factors. RESULTS: From July 2014 to November 2017, 37 patients who underwent 3DCRT and 32 patients who underwent VMAT were randomized into the study. Median overall survival was 9 months. Overall pain responses to RT were equivalent (P = .53) between the techniques. Patient compliance in returning QOL questionnaires was 94%, 81%, and 69% at baseline, 1 week after RT, and 1 month after RT, respectively. At 1 week after RT, change in global QOL was not significantly (P = .31) different between VMAT versus 3DCRT. At 4 weeks after RT, VMAT induced significantly (P = .049) less global QOL deterioration than 3DCRT did. Patients who underwent VMAT maintained better physical (P = .012), role (P = .041), and social (P = .025) functioning, but they reported more diarrhea symptoms (P = .017) than in the 3DCRT group. CONCLUSIONS: Palliative VMAT and 3DCRT did not differ in their ability to control pain; however, palliative VMAT induced fewer QOL detriments than 3DCRT did at 4 weeks after RT.

Patient Perceptions in a Nonblinded Randomized Trial of Radiation Therapy Technologies: A Novel Survey Study Exploring Therapeutic Misconception.

PURPOSE: Therapeutic misconception is the tendency for a clinical trial participant to overlook the scientific objective of a clinical trial and instead believe that an experimental intervention is intended for personal therapeutic benefit. We sought to evaluate this tendency in the setting of a clinical trial of a new radiation therapy technology. METHODS: Patients with left-sided, node positive breast cancer enrolled in a randomized clinical trial evaluating intensity modulated radiation therapy with deep inspiration breath hold (IMRT-DIBH) versus 3-dimensional conformal radiation therapy (3DCRT). Patients who enrolled completed surveys at baseline, after randomization, and upon completion of radiation therapy to evaluate expectations, satisfaction, and experiences. RESULTS: Forty women participated in the survey study, with 20 in each arm. Most participants endorsed the perception that participation in the trial might result in better treatment than the current standard treatment (77%) and more medical attention than being off trial (54%). At baseline, most women (74%) believed that a new treatment technology is superior than an established one. Before randomization, 43% of participants believed IMRT-DIBH would be more effective than standard treatment with 3DCRT, none believed that 3DCRT would be more effective, 23% believed that they would be the same, and 34% did not know. None believed that IMRT-DIBH would cause worse long-term side effects, whereas 37% thought that 3DCRT would. Most (71%) reported that they would choose to be treated with IMRT-DIBH; none would have elected 3DCRT if given a choice. Nearly half (44%) in the 3DCRT arm wished that they had been assigned to the IMRT-DIBH arm; none in the IMRT-DIBH arm expressed a wish for crossover. CONCLUSIONS: Most participants reported the perception that trial participation would result in better treatment and more medical attention than off trial, hallmarks of therapeutic misconception. Our observations provide empirical evidence of a fixed belief in the superiority of new technology and highlight the importance of adjusting expectations through informed consent to mitigate therapeutic misconception.

Central Airway Toxicity After High Dose Radiation: A Combined Analysis of Prospective Clinical Trials for Non-Small Cell Lung Cancer.

PURPOSE: To study the dosimetric risk factors for radiation-induced proximal bronchial tree (PBT) toxicity in patients treated with radiation therapy for non-small cell lung cancer (NSCLC). METHODS AND MATERIALS: Patients with medically inoperable or unresectable NSCLC treated with conventionally fractionated 3-dimensional conformal radiation therapy (3DCRT) in prospective clinical trials were eligible for this study. Proximal bronchial tree (PBT) and PBT wall were contoured consistently per RTOG 1106 OAR-Atlas. The dose-volume histograms (DVHs) of physical prescription dose (DVHp) and biological effective dose (α/ß = 2.5; DVH2.5) were generated, respectively. The primary endpoint was PBT toxicities, defined by CTCAE 4.0 under the terminology of bronchial stricture/atelectasis. RESULTS: Of 100 patients enrolled, with a median follow-up of 64 months (95% confidence interval [CI], 50-78), 73% received 70 Gy or greater and 17% developed PBT toxicity (grade 1, 8%; grade 2, 6%; grade 3, 0%; and grade 4, 3%). The median time interval between RT initiation and onset of PBT toxicity was 8.4 months (95% CI, 4.7-44.1). The combined DVHs showed that no patient with a PBT maximum physical dose <65 Gy developed any PBT toxicity. Cox proportional hazards analysis and receiver operating characteristic analysis demonstrated that V75 of PBT was the most significant dosimetric parameter for both grade 1+ (P = .035) and grade 2+ (P = .037) PBT toxicities. The dosimetric thresholds for V75 of PBT were 6.8% and 11.9% for grade 1+ and grade 2+ PBT toxicity, respectively. CONCLUSIONS: V75 of PBT appeared be the most significant dosimetric parameter for PBT toxicity after conventionally fractionated thoracic 3DCRT. Constraining V75 of PBT can limit clinically significant PBT toxicity.

An IAEA survey of radiotherapy practice including quality assurance extent and depth.

Background: The IAEA recommends a quality assurance program in radiotherapy to ensure safe and effective treatments. In this study, radiotherapy departments were surveyed on their current practice including the extent and depth of quality assurance activities.Methods: Radiotherapy departments were voluntarily surveyed in three stages, firstly, in basic facility information, secondly, in quality assurance activities and treatment techniques, and thirdly, in a snapshot of quality assurance, departmental and treatment activities.Results: The IAEA received completed surveys from 381 radiotherapy departments throughout the world with 100 radiotherapy departments completing all three surveys. Dominant patterns were found in linac-based radiotherapy with access to treatment planning systems for 3D-CRT and 3D imaging. Staffing levels for major staff groups were on average in the range recommended by the IAEA. The modal patient workload per EBRT unit was as expected in the range of 21-30 patients per day, however significant instances of high workload (more than 50 patients per day per treatment unit) were reported. Staffing levels were found to correlate with amount of treatment equipment and patient workload. In a self-assessment of quality assurance performance, most radiotherapy departments reported that they would perform at least 60% of the quality assurance activities itemized in the second survey, with particular strength in equipment quality control. In a snapshot survey of quality assurance performance, again equipment quality control practice was well developed, particularly for the treatment equipment.Conclusions: The IAEA surveys provide a snapshot of current radiotherapy practice including quality assurance activities.

The influence of errors in small field dosimetry on the dosimetric accuracy of treatment plans.

Background: Dosimetric effects of inaccuracies of output factors (OFs) implemented in treatment planning systems (TPSs) were investigated.Materials and methods: Modified beam models (MBM) for which the OFs of small fields (down to 1 × 1 cm2) were increased by up to 12% compared to the original beam models (OBM) were created for two TPSs. These beam models were used to recalculate treatment plans of different complexity. Treatment plans using stereotactic 3D-conformal (s3D-CRT) for brain metastasis as well as VMAT plans for head and neck and prostate cancer patients were generated. Dose distributions calculated with the MBM and the OBM were compared to measured dose distributions acquired using film dosimetry and a 2D-detector-array. For the s3D-CRT plans the calculated and measured dose at the isocenter was evaluated. For VMAT, gamma pass rates (GPRs) were calculated using global gamma index with 3%/3 mm, 2%/3 mm, 1%/3 mm and 2%/2 mm with a 20% threshold. Contribution of small fields to the total fluence was expressed as the ratio (F) of fluence trough leaf openings smaller than 2 cm to the total fluence.Results: Using film dosimetry for the s3D-CRT plans, the average of the ratio of calculated dose to measured dose at the isocenter was 1.01 and 1.06 for the OBM and MBM model, respectively. A significantly lower GPR of the MBM compared to the OBM was only found for the localized prostate cases (F = 12.4%) measured with the 2D-detector-array and an acceptance criterion of 1%/3 mm.Conclusion: The effects of uncertainties in small field OFs implemented in TPSs are most pronounced for s3D-CRT cases and can be clearly identified using patient specific quality assurance. For VMAT these effects mainly remain undetected using standard patient specific quality assurance. Using tighter acceptance criteria combined with an analysis of the fluence generated by small fields can help identifying inaccuracies of OFs implemented in TPSs.

External Beam Radiation Therapy (EBRT) and High-Dose-Rate (HDR) Brachytherapy for Intermediate and High-Risk Prostate Cancer: The Impact of EBRT Volume.

PURPOSE: Whole pelvis radiation therapy (WPRT) may improve clinical outcomes over prostate-only radiation therapy (PORT) in high-risk prostate cancer patients by sterilization of micrometastatic nodal disease, provided there is optimal control of the primary site. METHODS AND MATERIALS: A prospective multicenter cohort study of eligible patients (stage ≥T2c, Gleason score ≥7 or presenting prostate-specific antigen ≥10) treated between 2009 and 2013 were enrolled in a United Kingdom national protocol delivering combined external beam radiation therapy and high-dose-rate brachytherapy. Centers elected to deliver WPRT, 46 Gy in 23 fractions or PORT 37.5 Gy in 15 fractions with 15 Gy single dose high-dose-rate brachytherapy. The primary endpoint was biochemical progression-free survival (bPFS). Secondary endpoints were overall survival, genitourinary, and gastrointestinal toxicity. This was not a randomized comparison and was subject to bias; the findings are therefore hypothesis generating, but not conclusive. RESULTS: Eight hundred and twelve patients were entered; 401 received WPRT and 411 received PORT. With a median follow-up of 4.7 years, 5-year bPFS rates for WPRT versus PORT arms were 89% versus 81% (P = .007) for all patients and 84% versus 77% (P = .001) for high-risk patients. Differences in bPFS remained significant after accounting for Gleason score, presenting prostate-specific antigen, T stage, and androgen deprivation therapy duration as covariates. There was no difference in overall survival. The overall post treatment toxicities across both cohorts were low with no greater than 1.5% of ≥grade 3 toxicities at any follow-up time point. WPRT increased both prevalence and cumulative incidence of acute genitourinary toxicity (P = .004) and acute gastrointestinal toxicity (P = .003). No difference in late radiation toxicity was observed. CONCLUSIONS: A significant improvement in 5-year bPFS was seen in intermediate and high-risk prostate cancer treated with WPRT compared with PORT in a combined external beam radiation therapy and brachytherapy schedule with no increase in late radiation toxicity.

Cosmesis in patients with breast neoplasia submitted to the hypofractionated radiotherapy with of intensity-modulated beam.

OBJECTIVE: To assess the cosmetic satisfaction of patients diagnosed with breast cancer submitted to the hypofractionated radiotherapy with IMRT (hIMRT) technique and its correlation with dosimetric data of the radiotherapy planning. METHODS: The retrospective cohort study that assessed women with a diagnosis of malignant breast neoplasia submitted to the conservative treatment or radical mastectomy and treated with hIMRT. In the period between August 2007 to December 2014, in a philanthropic / private institution, 170 records were selected. The cosmetic assessment was carried out by means of the Harvard/RTOG/NSABP scale with one-year minimum range after treatment. The collected dosimetric data were: breast / chest wall volume, volume that received 95% (V95%) and 107% (V107%) of the prescribed dose. RESULTS: The volume of the treated breasts ranged from 169 to 2.103 ml (median = 702; IQR: 535 to 914 ml). Median V95% was 86.7% (54.6-96.6%; IQR: 80.0% to 90.6%); eight (5.7%) patients had V95% higher than 95%. Median V107% was 0% (0%-16.3%; IQR: 0.0% to 0.3% and 13); 9.3% patients had V107% higher than 2%. One hundred and thirty-three (78.2%) patients responded to the cosmetic assessment: 99 (74.4%) considered the cosmetic results excellent. Significant associations between cosmetic assessment and breast volume (p=0.875), V95% (p=0.294) e V107% (p=0.301) were not found. CONCLUSION: The cosmetic results showed favorable when using hIMRT, and the lack of correlation with usual the dosimetric data illustrates the capacity of hIMRT to minimize the heterogeneity of the dose in this endpoint, even in voluminous breasts.

Cosmesis in patients with breast neoplasia submitted to the hypofractionated radiotherapy with of intensity-modulated beam

SUMMARY OBJECTIVE: To assess the cosmetic satisfaction of patients diagnosed with breast cancer submitted to the hypofractionated radiotherapy with IMRT (hIMRT) technique and its correlation with dosimetric data of the radiotherapy planning. MATERIALS AND METHODS: The retrospective cohort study that assessed women with a diagnosis of malignant breast neoplasia submitted to the conservative treatment or radical mastectomy and treated with hIMRT. In the period between August 2007 to December 2014, in a philanthropic / private institution, 170 records were selected. The cosmetic assessment was carried out by means of the Harvard/RTOG/NSABP scale with one-year minimum range after treatment. The collected dosimetric data were: breast / chest wall volume, volume that received 95% (V95%) and 107% (V107%) of the prescribed dose. RESULTS: The volume of the treated breasts ranged from 169 to 2.103 ml (median = 702; IQR: 535 to 914 ml). Median V95% was 86.7% (54.6-96.6%; IQR: 80.0% to 90.6%); eight (5.7%) patients had V95% higher than 95%. Median V107% was 0% (0%-16.3%; IQR: 0.0% to 0.3% and 13); 9.3% patients had V107% higher than 2%. One hundred and thirty-three (78.2%) patients responded to the cosmetic assessment: 99 (74.4%) considered the cosmetic results excellent. Significant associations between cosmetic assessment and breast volume (p=0.875), V95% (p=0.294) e V107% (p=0.301) were not found. CONCLUSION: The cosmetic results showed favorable when using hIMRT, and the lack of correlation with usual the dosimetric data illustrates the capacity of hIMRT to minimize the heterogeneity of the dose in this endpoint, even in voluminous breasts.

RESUMO OBJETIVO: Avaliar a satisfação cosmética de pacientes diagnosticadas com câncer de mama submetidas à radioterapia hipofracionada com técnica IMRT (hIMRT) e sua correlação com dados dosimétricos do planejamento radioterápico. MATERIAIS E MÉTODOS: Estudo de coorte retrospectivo que avaliou mulheres com diagnóstico de neoplasia maligna de mama submetidas a tratamento conservador ou mastectomia radical e tratadas com hIMRT. No período de agosto de 2007 a dezembro de 2014, em uma instituição filantrópica/particular, foram selecionados 170 prontuários. A avaliação cosmética foi feita por meio da escala de Harvard/RTOG/NSABP com um intervalo mínimo de um ano após o tratamento. Dados dosimétricos coletados foram: volume da mama/plastrão, volume que recebeu 95% (V95%) e 107% (V107%) da dose prescrita. RESULTADOS: O volume das mamas tratadas variou de 169 a 2.103 ml (mediana = 702; IQR: 535 a 914 ml). O V95% mediano foi 86,7% (54,6-96,6%; IQR: 80,0% a 90,6%); oito (5,7%) pacientes tiveram o V95% superior a 95%. O V107% mediano foi 0% (0%-16,3%; IQR: 0,0% a 0,3% e 13); 9,3% pacientes tiveram o V107% superior a 2%. Cento e trinta e três (78,2%) pacientes responderam à avaliação cosmética: 99 (74,4%) consideraram o resultado cosmético excelente. Não foram encontradas associações significativas entre a avaliação cosmética e o volume da mama (p=0,875), V95% (p=0,294) e V107% (p=0,301). CONCLUSÕES: Os resultados cosméticos mostraram-se favoráveis com o uso de hIMRT, e a ausência de correlação com os dados dosimétricos usuais ilustra a capacidade do hIMRT em minimizar a heterogeneidade da dose neste desfecho, mesmo em mamas volumosas.

Tracking tumor boundary using point correspondence for adaptive radio therapy.

BACKGROUND AND OBJECTIVE: Tracking mobile tumor regions during the treatment is a crucial part of image-guided radiation therapy because of two main reasons which negatively affect the treatment process: (1) a tiny error will lead to some healthy tissues being irradiated; and (2) some cancerous cells may survive if the beam is not accurately positioned as it may not cover the entire cancerous region. However, tracking or delineation of such a tumor region from magnetic resonance imaging (MRI) is challenging due to photometric similarities of the region of interest and surrounding area as well as the influence of motion in the organs. The purpose of this work is to develop an approach to track the center and boundary of tumor region by auto-contouring the region of interest in moving organs for radiotherapy. METHODS: We utilize a nonrigid registration method as well as a publicly available RealTITracker algorithm for MRI to delineate and track tumor regions from a sequence of MRI images. The location and shape of the tumor region in the MRI image sequence varies over time due to breathing. We investigate two approaches: the first one uses manual segmentation of the first frame during the pretreatment stage; and the second one utilizes manual segmentation of all the frames during the pretreatment stage. RESULTS: We evaluated the proposed approaches over a sequence of 600 images acquired from 6 patients. The method that utilizes all the frames in the pretreatment stage with moving mesh based registration yielded the best performance with an average Dice Score of 0.89 ±â€¯0.04 and Hausdorff Distance of 3.38 ±â€¯0.10 mm. CONCLUSIONS: This study demonstrates a promising boundary tracking tool for delineating the tumor region that can deal with respiratory movement and the constraints of adaptive radiation therapy.

Clinical evaluation of intensity-modulated radiotherapy for locally advanced pancreatic cancer.

BACKGROUND: The purpose was to retrospectively evaluate the effect of intensity-modulated radiotherapy (IMRT) on gastrointestinal (GI) toxicities and outcomes compared to three-dimensional conformal radiotherapy (3DCRT) for locally advanced pancreatic cancer (LAPC). METHODS: We included 107 consecutive patients who underwent CRT for LAPC from September 2001 to March 2015; 80 patients underwent 3DCRT and 27 patients underwent IMRT. They were compared for GI toxicities, locoregional progression free survival (LRPFS), distant metastasis free survival (DMS), and overall survival (OS). RESULTS: Median radiation dose and fractions for 3DCRT and IMRT were 54 Gy/30 fr. and 48 Gy/15 fr. The regimens of CRT consisted of weekly gemcitabine 250 mg/m2 (for 3DCRT) or 1000 mg/m2 (for IMRT). Acute GI toxicity ≥grade 2 occurred in 32 patients (40%) treated with 3DCRT compared with five patients (19%) treated with IMRT. Late GI toxicity of grade 3 occurred in 10 patients (12%) treated with 3DCRT and one patient (4%) treated with IMRT. Patients who underwent IMRT had superior 1-year LRPFS (73.1% vs. 63.2%, p = 0.035) and 1-year OS (92.3% vs. 68.2%, p = 0.037) as compared with those treated with 3DCRT. Multivariate analysis showed that in IMRT patients, higher dose (≥45 Gy) was an independent factor for better LRPFS and OS. CONCLUSIONS: LAPC patients treated with hypofractionated full-dose gemcitabine IMRT had improved OS and LRPFS without increased GI toxicities when compared to those of patients treated with conventionally fractionated low dose gemcitabine 3DCRT. In IMRT patients, higher dose was an independent favorable prognostic factor for better LRPFS and OS, which suggests that dose escalation with IMRT for LAPC is a promising strategy.

Comparison of acute toxicities between contemporary forward-planned 3D conformal radiotherapy and inverse-planned intensity-modulated radiotherapy for whole breast radiation.

The use of inverse-planned intensity-modulated radiation therapy for whole breast radiation treatment has become more prevalent, but this may impose an increased cost on the health system. We hypothesized that when applied with the same treatment planning goals, tangential forward-planned field-in-field 3D conformal radiotherapy and tangential inverse-planned intensity-modulated radiotherapy would be associated with comparable toxicities. Women who underwent tangential whole breast irradiation at our institution from 2011 to 2015 planned using either forward-planned field-in-field 3D conformal radiotherapy or intensity-modulated radiotherapy were retrospectively analyzed. Grade 2+ Radiation dermatitis was the primary endpoint. A total of 201 and 212 women had undergone field-in-field 3D conformal radiotherapy and intensity-modulated radiotherapy, respectively. No differences were observed between the two modalities regarding acute radiation dermatitis, breast pain, or fatigue. In a multivariable logistic regression that incorporated the use of boost, hypofractionation, use of chemotherapy, patient positioning, use of a supraclavicular field, and breast planning target volume, intensity-modulated radiotherapy was not correlated with different rates of Grade 2+ radiation dermatitis. This study supports the routine first-line use of field-in-field 3D conformal radiotherapy for whole breast radiation instead of tangential intensity-modulated radiotherapy from the standpoint of equivalence in acute toxicity. Further investigation is needed to assess whether there are subgroups of women who may still benefit from intensity-modulated radiotherapy.

National Population-Based Study Comparing Treatment-Related Toxicity in Men Who Received Intensity Modulated Versus 3-Dimensional Conformal Radical Radiation Therapy for Prostate Cancer.

PURPOSE: To compare, in a national population-based study, severe genitourinary (GU) and gastrointestinal (GI) toxicity in patients with prostate cancer who were treated with radical intensity modulated radiation therapy (IMRT) or 3-dimensional conformal radiation therapy (3D-CRT). METHODS AND MATERIALS: Patients treated with IMRT (n=6933) or 3D-CRT (n=16,289) between January 1, 2010 and December 31, 2013 in the English National Health Service were identified using cancer registry data, the National Radiotherapy Dataset, and Hospital Episodes Statistics, the administrative database of care episodes in National Health Service hospitals. We developed a coding system that identifies severe toxicity (at least grade 3 according to the National Cancer Institute Common Terminology Criteria for Adverse Events scoring system) according to the presence of a procedure and a corresponding diagnostic code in patients' Hospital Episodes Statistics records after radiation therapy. A competing risks regression analysis was used to estimate hazard ratios (HRs), comparing the incidence of severe GI and GU complications after IMRT and 3D-CRT, adjusting for patient, disease, and treatment characteristics. RESULTS: The use of IMRT, as opposed to 3D-CRT, increased from 3.1% in 2010 to 64.7% in 2013. Patients who received IMRT were less likely than those receiving 3D-CRT to experience severe GI toxicity (4.9 vs 6.5 per 100 person-years; adjusted HR 0.66; 95% confidence interval 0.61-0.72) but had similar levels of GU toxicity (2.3 vs 2.4 per 100 person-years; adjusted HR 0.94; 95% confidence interval 0.84-1.06). CONCLUSIONS: Prostate cancer patients who received radical radiation therapy using IMRT were less likely to experience severe GI toxicity, and they had similar GU toxicity compared with those who received 3D-CRT. These findings in an unselected "real-world" population support the use of IMRT, but further cost-effectiveness studies are urgently required.

Photon and Proton Radiation Therapy Utilization in a Population of More Than 100 Million Commercially Insured Patients.

PURPOSE: To characterize the changes in the use of radiation therapy (RT), specifically proton beam radiation therapy (PBRT), among adult and pediatric patients over a 11-year period in a very large population of insured patients. METHODS AND MATERIALS: We conducted a retrospective analysis of the OptumLabs Data Warehouse claims database of more than 100 million insured US enrollees. Descriptive analyses were undertaken to evaluate the characteristics of patients receiving RT from 2002 to 2012. RESULTS: There were 474,533 patients treated with RT from 2002 to 2012. The percentage of patients treated with 3-dimensional conformal radiation therapy, 2-dimensional RT/brachytherapy, intensity modulated radiation therapy (IMRT), stereotactic body radiation therapy (SBRT), and PBRT was 34.5%, 63.4%, 2.1%, 0.0%, and 0.1% and 40.4%, 36.0%, 21.9%, 1.1%, and 0.6% in 2002 and 2012, respectively. The greatest increase in utilization was of IMRT for prostate cancer, growing from 3.5% to 64.0%. For non-prostate cancer adults, IMRT use grew from 1.7% to 16.4%. For children, PBRT utilization increased from 0.3% to 9.7%. For prostate cancer patients, PBRT increased from 0.0% to 2.6%. For all patients, advanced technology (SBRT and PBRT) use was very low at <2%, versus 22% for IMRT. CONCLUSIONS: This is the largest and most geographically diverse description of RT utilization. Proton beam RT utilization remains very low and has had little impact on overall RT utilization compared with IMRT. The largest shift has occurred in IMRT for prostate cancer. Our findings indicate that overall utilization of proton therapy has been low and that its use has likely had little impact on national expenditures on cancer care in the current environment.

Patterns of failure of diffuse large B­cell lymphoma patients after involved-site radiotherapy.

PURPOSE: Radiotherapy (RT) in combination with chemoimmunotherapy is highly efficient in the treatment of diffuse large B­cell lymphoma (DLBCL). This retrospective analysis evaluated the efficacy of the treatment volume and the dose concept of involved-site RT (ISRT). PATIENTS AND METHODS: We identified 60 histologically confirmed stage I-IV DLBCL patients treated with multimodal cytotoxic chemoimmunotherapy and followed by consolidative ISRT from 2005-2015. Progression-free survival (PFS) and overall survival (OS) were estimated by Kaplan-Meier method. Univariate analyses were performed by log-rank test and Mann-Whitney U­test. RESULTS: After initial chemoimmunotherapy (mostly R­CHOP; rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone), 19 (36%) patients achieved complete response (CR), 34 (64%) partial response (PR) or less. Excluded were 7 (12%) patients with progressive disease after chemoimmunotherapy. All patients underwent ISRT with a dose of 40 Gy. After a median follow-up of 44 months, 79% of the patients remained disease free, while 21% presented with failure, progressive systemic disease, or death. All patients who achieved CR after chemoimmunotherapy remained in CR. Of the patients achieving PR after chemotherapy only 2 failed at the initial site within the ISRT volume. No marginal relapse was observed. Ann Arbor clinical stage I/II showed significantly improved PFS compared to stage III/IV (93% vs 65%; p ≤ 0.021). International Prognostic Index (IPI) score of 0 or 1 compared to 2-5 has been associated with significantly increased PFS (100% vs 70%; p ≤ 0.031). Postchemoimmunotherapy status of CR compared to PR was associated with significantly increased PFS (100% vs 68%; p ≤ 0.004) and OS (100% vs 82%; p ≤ 0.026). Only 3 of 53 patients developed grade II late side effects, whereas grade III or IV side effects have not been observed. CONCLUSION: These data suggest that a reduction of the RT treatment volume from involved-field (IF) to involved-site (IS) is sufficient because no marginal failures occurred. The concept of IS will likely reduce the risk for late sequelae of RT.

Commissioning of beam shaper applicator for conformal intraoperative electron radiotherapy.

Beam shaper is a newly designed device for beam shaping in IOERT. The aim of this study is evaluating the performance of this device for conformal IOERT and preparing it for clinical applications. Dosimetric characteristics for different combinations of energy/field size were determined by ionometric dosimetry, film dosimetry and Monte Carlo simulation. Desirable dosimetric characteristics of beam shaper make it a useful tool for conformal IOERT. Usability of Monte Carlo simulation in any clinical setup of beam shaper was demonstrated.