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1.
BMC Cancer ; 21(1): 915, 2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34384377

RESUMO

BACKGROUND: Intracranial hemangiopericytoma is a rare disease and surgery is the mainstay treatment. Although postoperative adjuvant radiotherapy is often used, there are no reports comparing different radiotherapy techniques. The purpose of this study is to analyze the impact of post-operative radiotherapy and different radiotherapy technique on the results in patients with intracranial hemangiopericytoma (HPC). METHODS: We retrospectively reviewed 66 intracranial HPC patients treated between 1999 and 2019 including 29 with surgery followed by radiotherapy (11 with intensity-modulated radiotherapy (IMRT) and 18 with stereotactic radiosurgery (SRS)) and 37 with surgery alone. Chi-square test was used to compare the clinical characteristic between the groups. The Kaplan-Meier method was used to analyze overall survival (OS) and recurrence-free survival (RFS). Multivariate Cox proportional hazards models were used to examine prognostic factors of survival. We also underwent a matched-pair analysis by using the propensity score method. RESULTS: The crude local control rates were 58.6% in the surgery plus post-operative radiotherapy group (PORT) and 67.6% in the surgery alone group (p = 0.453). In the subgroup analysis of the PORT patients, local controls were 72.7% in the IMRT group and 50% in the SRS group (p = 0.228). The median OS in the PORT and surgery groups were 122 months and 98 months, respectively (p = 0.169). The median RFS was 96 months in the PORT group and 72 months in the surgery alone group (p = 0.714). Regarding radiotherapy technique, the median OS and RFS of the SRS group were not significantly different from those in the IMRT group (p = 0.256, 0.960). The median RFS were 112 and 72 months for pathology grade II and III patients, respectively (p = 0.001). Propensity score matching did not change the observed results. CONCLUSION: In this retrospective analysis, PORT did not improve the local control rates nor the survivals. The local control rates after IMRT and SRS were similar even though the IMRT technique had a much higher biological dose compared with the SRS technique.


Assuntos
Neoplasias Encefálicas/radioterapia , Hemangiopericitoma/radioterapia , Cuidados Pós-Operatórios , Adulto , Idoso , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/mortalidade , Terapia Combinada , Feminino , Hemangiopericitoma/diagnóstico , Hemangiopericitoma/mortalidade , Humanos , Estimativa de Kaplan-Meier , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Modelos de Riscos Proporcionais , Radiocirurgia , Radioterapia de Intensidade Modulada , Recidiva , Estudos Retrospectivos , Resultado do Tratamento
2.
J Appl Clin Med Phys ; 17(1): 428­439, 2016 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-26894355

RESUMO

The construction of a conventional prostate needle (seeds) implant template restricts needles tilting or incline insertion when it is necessary to approach a seminal vesicle or to avoid the obstruction of symphysis pubis. To overcome the disadvantages of conventional templates, we developed a special template for guiding needles incline insertion and fixation for prostate needle implant. Phantom needles implantation was performed. Two acrylic boards, each 7.5 cm in width by 7.5 cm in length and 0.5 cm thickness, were drilled with a set of domed holes and cones with embedded template ball inside this combination to provide firm grip and fixation in prostate needle implantation. The specially designed domed-cones combination acrylic board provides a needle of up to 60° rotation flexibility application. Some areas that could not be covered in a conventional parallel needle holes template could now be covered by using this new template. The covering index of prostate radiation dosage is up to 84.5%. The specially designed domed-cones acrylic board combination provides not only a reliable means of needle fixation and rotational function, but also a superior dose distribution in the anterior portion of the prostate and good coverage of a seminal vesicle. This special template is a feasible design for prostate needles or seeds implant brachytherapy.


Assuntos
Braquiterapia , Imagens de Fantasmas , Neoplasias da Próstata/radioterapia , Próteses e Implantes , Humanos , Masculino , Agulhas , Radiometria , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Rotação
3.
Clin Gastroenterol Hepatol ; 12(8): 1288-94, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24361412

RESUMO

BACKGROUND & AIMS: We investigated whether a diagnosis of colonic diverticular disease is associated with an increased risk for subsequent development of colorectal cancer (CRC) in a nationwide population-based retrospective study. METHODS: We identified 41,359 individuals diagnosed with colonic diverticular disease as inpatients from 2000 through 2009 from the Taiwan National Health Insurance Research Database (study cohort) and collected data for 165,436 randomly selected additional subjects, matched by sex, age, and baseline year (comparison cohort). Data were collected until individuals developed CRC or withdrew from the National Health Insurance system, or until December 31, 2010. Cumulative incidences and hazard ratios (HRs) of CRC development were determined. To assess for ascertainment bias, we conducted an analysis excluding the first 12 months of follow-up evaluation. RESULTS: The risk of CRC was significantly higher in the study cohort than in the comparison cohort (HR adjusted for age, sex, and comorbidities, 4.54; 95% confidence interval, 4.19-4.91; P < .0001). In a sensitivity analysis, we excluded the first 12 months of follow-up evaluation after a diagnosis of colonic diverticular disease; subsequent incidence rates for CRC in the study and comparison cohorts were 15.13 and 15.74 per 10,000 person-years, respectively (adjusted HR, 0.96; 95% confidence interval, 0.83-1.11). CONCLUSIONS: Colonic diverticular disease is not associated with an increased risk of subsequent CRC after the first year of diagnosis of colonic diverticular disease. An increased risk was observed in the first year, possibly owing to misclassification and screening effects.


Assuntos
Neoplasias Colorretais/epidemiologia , Doença Diverticular do Colo/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Taiwan/epidemiologia
4.
J Gastroenterol Hepatol ; 29(11): 1919-25, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25041220

RESUMO

BACKGROUND AND AIM: This study aimed to evaluate the outcomes and toxicities of repeated stereotactic ablative radiotherapy (SABR) in hepatocellular carcinoma (HCC). METHODS: Fourteen HCC patients with local recurrence (18 lesions) after liver SABR received repeated radiotherapy with SABR using CyberKnife. No patients experienced radiation-induced liver disease after the first SABR course. The median first SABR dose was 41 Gy (range, 34-60 Gy); the median second SABR dose, 40 Gy (range, 25-50 Gy); and the median interval, 12.9 months. Local recurrence was divided into in-field recurrence and out-field recurrence. RESULTS: Objective responses were observed in 11 tumors (61.1%), including five tumors (27.8%) with complete responses. Intrahepatic out-field failure was the main cause of treatment failure (7 of 14 patients). In-field failure had developed in 1 of 18 tumors (5.6%), resulting in a 2-year in-field failure-free rate of 88.2%. The median time to progression was 14.0 months, with 1- and 2-year progression-free survival rates of 68.6% and 42.9%, respectively. One- and two-year overall survival rates were 76% and 59.1%, respectively. Of the 14 patients, one developed radiation-induced liver disease and three showed progression of the Child-Turcotte-Pugh class after the second SABR course. Other toxicities were generally mild and tolerable. CONCLUSION: Repeated SABR in selected HCC patients is feasible with acceptable toxicity.


Assuntos
Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Recidiva Local de Neoplasia/cirurgia , Radiocirurgia/métodos , Idoso , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiocirurgia/mortalidade , Dosagem Radioterapêutica , Reoperação , Taxa de Sobrevida , Resultado do Tratamento
5.
Med Dosim ; 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37858458

RESUMO

This study aims to establish a delineation guideline for the contouring of the hypoglossal nerve by dividing the nerve into different segments, and to test the possibility of a radiation dose reduction to the hypoglossal nerve in NPC patients receiving radiotherapy. Twenty NPC patients were selected arbitrarily. The hypoglossal nerves were delineated using anatomic landmarks and divided into the cisternal, intracanalicular, carotid, and transverse segments. The tumor coverage by radiation and dose-volume parameters of the nerve with and without various dose constraints to the hypoglossal nerve were compared. The hypoglossal nerve, which is invisible on CT images, can be delineated accurately with the assistance of several anatomic landmarks. Without a dose constraint to the hypoglossal nerve, the carotid space, intracanalicular, and transverse segments had high radiation dose-volumes. The dose-volume to the nerve, however, can be reduced when the nerve was defined and a dose constraint was given. The delineation of the hypoglossal nerve with its different segments is feasible. The carotid space, intracanalicular, and transverse segments received the highest dose, where the nerve damage was most likely located. The dose to the nerve can be reduced to less than 70 Gy using the intensity-modulated radiotherapy technique.

6.
Sci Rep ; 12(1): 22604, 2022 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-36585458

RESUMO

Precision radiotherapy needs to manage organ movements to prevent critical organ injury. The purpose of this study is to examine the feasibility of motion control of the lung by suppressing respiratory motion. The non-invasive high frequency oscillatory ventilation (NIHFOV) is a technique commonly used in the protection of lung for patients with acute lung disease. By using a very high respiratory frequency and a low tidal volume, NIHFOV allows gas exchange, maintains a constant mean airway pressure and minimizes the respiratory movements. We tested healthy volunteers NIHFOV to explore the optimal operational parameter setting and the best possible motion suppression achievable. This study was conducted with the approval of Institutional Review Boards of the Wuwei Cancer hospital (approval number: 2021-39) and carried out in accordance with Declaration of Helsinki. The study comprises two parts. Twenty three healthy volunteers participated in the first part of the study. They had 7 sessions of training with the NIHFOV. The duration of uninterrupted, continuous breathing under the NIHFOV and the optimal operational machine settings were defined. Eight healthy volunteers took part in the second part of the study and underwent 4-dimensional CT (4DCT) scanning with and without NIHFOV. Their respiratory waveform under free breathing (FB) and NIHFOV were recorded. The maximum range of motion of the diaphragm from the two scannings was compared, and the variation of bilateral lung volume was obtained to evaluate the impact of NIHFOV technique on lung volume. The following data were collected: comfort score, transcutaneous partial pressure of oxygen (PtcO2), transcutaneous partial pressure of carbon dioxide (PtcCO2), and pulse rate. Data with and without NIHFOV were compared to evaluate its safety, physiological impacts and effect of lung movement suppression. All the volunteers completed the training sessions eventlessly, demonstrating a good tolerability of the procedure. The median NIHFOV-on time was 32 min (22-45 min), and the maximum range of motion in the cephalic-caudal direction was significantly reduced on NIHFOV compared with FB (1.8 ± 0.8 cm vs 0.3 ± 0.1 cm, t = - 3.650, P = 0.003); the median range of motion was only 0.3 ± 0.1 cm on NIHFOV with a good reproducibility. The variation coefficient under NIHFOV of the right lung volume was 2.4% and the left lung volume was 9.2%. The PtcO2 and PtcCO2 were constantly monitored during NIHFOV. The medium PtcCO2 under NIHFOV increased lightly by 4.1 mmHg (interquartile range [IQR], 4-6 mmHg) compared with FB (t = 17.676, P < 0.001). No hypercapnia was found, PtcO2 increased significantly in all volunteers during NIHFOV (t = 25.453, P < 0.001). There was no significant difference in pulse rate between the two data sets (t = 1.257, P = 0.233). NIHFOV is easy to master in healthy volunteers to minimize respiratory movement with good tolerability and reproducibility. It is a feasible approach for lung motion control and could potentially be applied in accurate radiotherapy including carbon-ion radiotherapy through suppression of respiratory movement.


Assuntos
Ventilação de Alta Frequência , Humanos , Voluntários Saudáveis , Reprodutibilidade dos Testes , Pulmão/diagnóstico por imagem , Respiração
7.
J Formos Med Assoc ; 110(10): 655-60, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21982471

RESUMO

This study reported our experience of the clinical characteristics of periparotid recurrence of nasopharyngeal carcinoma (NPC) after parotid-gland-sparing radiotherapy. We retrospectively reviewed the charts of 296 patients with NPC who underwent parotid-gland-sparing radiotherapy at the Tri-Service General Hospital from 1998 to 2008. Eighty-three patients underwent three-dimensional conformal radiotherapy, and 205 patients underwent intensity-modulated radiotherapy; parotid glands were spared bilaterally in all patients. None of these patients had undergone previous radiotherapy or surgical treatment of the head and neck. Disease recurred in a spared parotid gland in three patients (1.04%). Two of these patients had undergone three-dimensional conformal radiotherapy and the third underwent intensity-modulated radiotherapy. All three patients had undergone parotidectomy. Adjuvant radiotherapy or concurrent chemoradiation was administered. One patient died of metastatic disease 26 months after diagnosis of recurrence; the others were well with no evidence of disease at 63 and 6 months after initial recurrence. Periparotid recurrence is an uncommon pattern of locoregional failure after parotid-gland-sparing radiotherapy for NPC. Early diagnosis and aggressive therapy for patients with periparotid recurrence may improve outcomes.


Assuntos
Carcinoma/patologia , Carcinoma/radioterapia , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/radioterapia , Recidiva Local de Neoplasia/terapia , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Recidiva Local de Neoplasia/diagnóstico , Tratamentos com Preservação do Órgão , Glândula Parótida
8.
Medicine (Baltimore) ; 100(8): e24555, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33663063

RESUMO

ABSTRACT: Some nasopharyngeal carcinoma (NPC) patients may present convincing radiological evidence mimicking residual or recurrent tumor after radiotherapy. However, by means of biopsies and long term follow-up, the radiologically diagnosed residuals/recurrences are not always what they appear to be. We report our experience on this "phantom tumor" phenomenon. This may help to avoid the unnecessary and devastating re-irradiation subsequent to the incorrect diagnosis.In this longitudinal cohort study, we collected 19 patients of image-based diagnosis of residual/recurrent NPC during the period from Feb, 2010 to Nov. 2016, and then observed them until June, 2019. They were subsequently confirmed to have no residual/recurrent lesions by histological or clinical measures. Image findings and pathological features were analyzed.Six patients showed residual tumors after completion of radiotherapy and 13 were radiologically diagnosed to have recurrences based on magnetic resonance imaging (MRI) criteria 6 to 206 months after radiotherapy. There were 3 types of image patterns: extensive recurrent skull base lesions (10/19); a persistent or residual primary lesion (3/19); lesions both in the nasopharynx and skull base (6/19). Fourteen patients had biopsy of the lesions. The histological diagnoses included necrosis/ inflammation in 10 (52.7%), granulation tissue with inflammation in 2, and reactive epithelial cell in 1. Five patients had no pathological proof and were judged to have no real recurrence/residual tumor based on the absence of detectable plasma EB virus DNA and subjective judgment. These 5 patients have remained well after an interval of 38-121 months without anti-cancer treatments.Image-based diagnosis of residual or recurrent nasopharyngeal carcinoma may be unreliable. False positivity, the "phantom tumor phenomenon", is not uncommon in post-radiotherapy MRI. This is particularly true if the images show extensive skull base involvement at 5 years or more after completion of radiotherapy. MRI findings compatible with NPC features must be treated as a real threat until proved otherwise. However, the balance between under- and over-diagnosis must be carefully sought. Without a pathological confirmation, the diagnosis of residual or recurrent NPC must be made taking into account physical examination results, endoscopic findings and Epstein-Barr virus viral load. A subjective medical judgment is needed based on clinical and laboratory data and the unique anatomic complexities of the nasopharynx.


Assuntos
Carcinoma Nasofaríngeo/diagnóstico por imagem , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/diagnóstico por imagem , Neoplasias Nasofaríngeas/radioterapia , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Feminino , Herpesvirus Humano 4/genética , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/patologia , Carcinoma Nasofaríngeo/terapia , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/terapia , Terapia Neoadjuvante/métodos , Recidiva Local de Neoplasia/patologia , Neoplasia Residual/patologia , Carga Viral
9.
Med Dosim ; 45(3): 246-251, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32111451

RESUMO

We investigated to what extent can the dose-volumes of the coronary artery and the cardiac substructures be reduced by using IMRT technique in left-sided breast cancer patients. We chose 40 pN2M0 patients treated with postmastectomy IMRT. The original treatment plans were retrieved and the (internal mammary nodes) IMNs and cardiac substructure delineations were added. Three sets of dose-volume parameters including the original plans without internal mammary irradiation (IMNI), the plans with IMNI, and the plans with dose constraints to the heart, were derived. In left-sided patients, when IMNI was included, the V30 for right ventricle (RV), left ventricle (LV), pulmonic valve (PV), and left anterior descending artery (LADA) were 56.37% ± 7.9%, 25.3% ± 7.3%, 48.3% ± 6.3%, and 69.7% ± 6.4%, respectively. Of the 4 main coronary arteries, LADA had the highest dose followed by the left main coronary artery (LMCA). LADA had a V40 of 62% ± 9.7% vs 13.5% ± 3.5%, and a V50 of 27.5% ± 4.7% vs 0, with and without IMNI. For the right-sided patients, the V30s for all the heart substructures were 0 with or without IMNI. When we set a dose constraint of V40 < 10% for the LADA in the left-sided patients, the PTV volumes covered by 50 Gy decreased by only 1%. IMNI increased the V30 of the right and left ventricle and significantly increased the V40 and V50 to the LADA of left-sided breast cancer patients. IMRT markedly reduces the dose to the main coronary arteries and the right and left ventricle.


Assuntos
Vasos Coronários , Coração , Mastectomia , Radioterapia de Intensidade Modulada , Neoplasias Unilaterais da Mama/radioterapia , Neoplasias Unilaterais da Mama/cirurgia , Feminino , Humanos , Órgãos em Risco , Doses de Radiação , Radiometria , Dosagem Radioterapêutica , Tomografia Computadorizada por Raios X
10.
Eur Radiol ; 19(1): 94-102, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18661135

RESUMO

We aimed to quantitatively investigate the alteration of parotid perfusion after irradiation using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) based on a two-compartment tracer kinetic model. This study enrolled 19 patients (53.2 +/- 14.9 years) treated by head and neck radiotherapy and 19 age-relevant and sex-matched subjects as a control group. Perfusion parameters (K ( el ), k (21) and A) of parotid glands were analyzed based on the Brix model from T1-weighted DCE-MRI. Suitability of the Brix model was evaluated via Monte Carlo simulation for the goodness-of-fit. Analysis of nonlinear goodness-of-fit showed that the Brix model is appropriate in evaluating the parotid perfusion (R(2) = 0.938 +/- 0.050). The irradiated parotid glands showed significantly lower K ( el ) (P < 0.0005) and k (21) (P < 0.05) and consequently significantly higher value of peak enhancement (P < 0.0005) and time-to-peak (P < 0.0005) compared with non-irradiated ones, suggestive of gradual and prolonged accumulation and delayed wash-out of contrast agent due to increased extracellular extravascular space and decreased vascular permeability in the irradiated glands. Linear regression analysis showed dose-dependent perfusion changes of the irradiated parotid glands. We conclude that quantitative DCE-MRI is a potential tool in investigating parotid gland perfusion changes after radiotherapy.


Assuntos
Gadolínio DTPA , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Glândula Parótida/lesões , Glândula Parótida/patologia , Lesões por Radiação/diagnóstico , Lesões por Radiação/etiologia , Xerostomia/diagnóstico , Xerostomia/etiologia , Adulto , Idoso , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Glândula Parótida/irrigação sanguínea , Radiografia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
11.
Biomed Res Int ; 2019: 7584743, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31886248

RESUMO

PURPOSE: We developed a mathematic empirical model for describing the small field penumbra in order to analyze the potential dose perturbation caused by overlapping field to avoid the dose calculation errors in linear accelerator-based radiosurgery. MATERIALS AND METHODS: A ball phantom was fabricated for measuring penumbra at 4 different gantry angles in the coplanar plane. A least square root estimation (LSRE) Model was created to fit the measured penumbra dose profile and to predict the penumbra dose profile at any gantry angles. The Sum of Squared Errors (SSE) was used for finding the parameters n and t for the best fitting of the LSRE model. Geometric and mathematical methods were used to derive the model parameters. RESULTS: The results showed that the larger the gantry angle of the field, the more the expansion of the penumbra dose profile. The least square root estimation model for describing small field penumbra is as follows: Penumbra D s = T · 1 / 2 · 1 - s / n + s 2 + t where Penumbra D(s) denotes the dose profile D(s) at the penumbra region, T is the penumbra height (usually in scalar 100), n is the parameter for curvature, s = x - W d /2 (x and s are the values in cm on x-axis), and t is the radiation transmission of the collimator. Geometric analysis establishes the correlation between the penetration depth of the exposure and its effect on the penumbra region in ball phantom. The penumbra caused by an exposure at any arbitrary angles can be geometrically derived by using a one-variable quadratic equation. CONCLUSION: The dose distribution in penumbra region of small field can be created by the LSRE model and the potential overdosage or underdosage owing to overlapping field perturbation can be estimated.


Assuntos
Pesquisa Empírica , Planejamento da Radioterapia Assistida por Computador , Calibragem , Relação Dose-Resposta à Radiação , Imagens de Fantasmas , Dosagem Radioterapêutica , Análise de Regressão
12.
Head Neck ; 41(3): 598-605, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30597692

RESUMO

BACKGROUND: The purpose of this study was to present our comparison of the clinical outcome of patients with nasopharyngeal carcinoma (NPC) treated with whole-field intensity-modulated radiotherapy (whole-field-IMRT) or split-field-IMRT. METHODS: We retrospectively studied 388 patients with M0 NPC. The median lower neck doses were 50 Gy in 1.35 Gy/fractions for the 240 whole-field-IMRT patients, and 50.4 Gy in 1.8 to 2.0 Gy/fractions for the 148 split-field-IMRT patients. RESULTS: The IMRT technique did not affect the overall survival (OS; P = .077) and locoregional control (P = .231) rates. However, the split-field-IMRT group had more locoregional recurrences at the whole neck (P = .005) but not at the nasopharynx (P = .968) or the lower neck (P = .485). The patients treated with split-field-IMRT (43.2%) had more grade III neck fibrosis than the patients who received whole-field-IMRT (18.3%; P < .001). Only 1 patient had temporal lobe necrosis in our study. CONCLUSION: Our study shows that whole-field-IMRT using a lower dose/fraction for the lower neck results in at least comparable locoregional control and less fibrosis compared to conventional fraction with split-field-IMRT.


Assuntos
Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Radioterapia de Intensidade Modulada/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimiorradioterapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/tratamento farmacológico , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/patologia , Estadiamento de Neoplasias , Dosagem Radioterapêutica , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
13.
Thyroid ; 18(1): 51-5, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18302518

RESUMO

Primary malignant fibrous histiocytoma of thyroid is extremely rare. Only three cases have been reported. We report two cases of this rare disease. Case 1 was a 70-year-old woman who had Graves' disease and a growing 3.5-cm thyroid nodule with constrictive symptoms. Fine-needle aspiration cytology showed suspicious atypical cells. She had a total thyroidectomy; frozen section showed sarcoma. Final pathology showed malignant fibrous histiocytoma. Case 2 was a 67-year-old woman who had a 5-cm thyroid nodule that rapidly grew, causing tracheal deviation. A diagnostic lobectomy and pathology showed malignant fibrous histiocytoma. She then had a completion total thyroidectomy. Neither patient had metastatic lesions found by whole body gallium scans, computerized tomographic scans, and neck sonography. Both patients had postoperative radiotherapy and were alive and without recurrence at 6 months follow-up.


Assuntos
Histiocitoma Fibroso Maligno/diagnóstico , Neoplasias da Glândula Tireoide/diagnóstico , Idoso , Transformação Celular Neoplásica/patologia , Feminino , Doença de Graves/complicações , Doença de Graves/patologia , Histiocitoma Fibroso Maligno/etiologia , Histiocitoma Fibroso Maligno/terapia , Humanos , Radioterapia , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/etiologia , Neoplasias da Glândula Tireoide/terapia , Nódulo da Glândula Tireoide/complicações , Nódulo da Glândula Tireoide/patologia , Tireoidectomia
14.
Head Neck ; 40(9): 1977-1985, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29663564

RESUMO

BACKGROUND: The purpose of this study was to assess the predictive factors of optic neuropathy among patients with nasopharyngeal carcinoma (NPC). METHODS: The analysis included 16 297 patients with NPC and 65 187 controls. Each patient with NPC was randomly frequency-matched with 4 individuals without NPC by age, sex, and index year. Cox proportional hazard models were applied to measure the hazard ratios (HRs) and 95% confidence intervals (CIs) of optic neuropathy development associated with NPC. RESULTS: The risk of optic neuropathy was significantly higher in the NPC cohort (adjusted HR [aHR] 3.42; 95% CI 2.85-4.09; P < .001). Independent risk factors for optic neuropathy among patients with NPC included stroke (aHR 1.7; 95% CI 1.07-2.7; P = .03) and receipt of chemotherapy (aHR 1.55; 95% CI 1.17-2.06; P = .002). CONCLUSION: The risk of optic neuropathy was significantly higher in patients with NPC than in the general population.


Assuntos
Carcinoma Nasofaríngeo/complicações , Neoplasias Nasofaríngeas/complicações , Doenças do Nervo Óptico/epidemiologia , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Fatores de Risco
15.
Med Dosim ; 42(4): 251-267, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28733115

RESUMO

The purpose of this study was to realize the processing of dose distribution of RGK at the treatment isocenter at any gantry rotational angle by using an analytic geometry method to avoid inadequate arc therapy angles when implementing the treatment plan. Gaf chromic film was used for dose evaluation. A calibration curve was first obtained using linear accelerator irradiation. The 50% dose relative to the central axis at fixed gantry angles at the x-, y- and z-axes was obtained using Gaf chromic film and was compared to the analytic geometry method. The full width half maximum (FWHM) on the x-, y- and z-axes was predicted for the RGK dose distribution characteristic analysis. The FWHM on the x-, y-, and z-axes varies with different gantry and rotational plate angles. The most dramatic intersection variation appeared at a static gantry angle of 25°. The ratio of the FWHM of the y- and z-axes to that of the x-axis was up to 9 and 10. The geometric analytic method can be used for an accurate analysis of dose distribution in RGK replacing the actual film exposure experiment. It is essential to select the best arc irradiation angle to prescribe the dose to avoid excess irradiation of normal tissue. The geometric method used in this study can also be applied for rotational arc therapy dose analysis such as tomotherapy, linear-based stereotactic radiotherapy, or volume matrices arc therapy.


Assuntos
Radiocirurgia , Dosagem Radioterapêutica , Calibragem , Humanos , Rotação
16.
Int J Radiat Oncol Biol Phys ; 99(1): 145-152, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28816140

RESUMO

PURPOSE: To evaluate the prognostic performance of the Child-Turcotte-Pugh (CTP) score and the albumin-bilirubin (ALBI) score in hepatocellular carcinoma (HCC) patients treated using stereotactic ablative radiation therapy (SABR). METHODS AND MATERIALS: This retrospective study evaluated the data of patients with HCC who underwent SABR between December 2007 and June 2015. We collected pretreatment CTP and ALBI scores and analyzed their correlation with survival and liver toxicity. RESULTS: This study included 152 HCC patients: 78.3% of CTP class A and 21.7% of CTP class B. The median ALBI score was -2.49 (range, -3.67 to -0.84) with 39.5% of grade 1, 56.6% of grade 2, and 3.9% of grade 3. The CTP classification and ALBI grade were significantly associated with overall survival (P<.001). Albumin-bilirubin grade (1 vs 2) had a trend to stratify CTP class A patients into 2 risk groups of mortality (P=.061). Combined CTP class and ALBI score could predict development of radiation-induced liver disease (2.4% in CTP A-ALBI < -2.76, 15.1% in CTP A-ALBI ≥ -2.76, and 25.8% in CTP B). CONCLUSION: Albumin-bilirubin score is a potential predictor for both survival and liver toxicity. Complementary use of CTP and ALBI score could predict the risk of post-SABR liver toxicity. Further prospective studies are necessary before use of the ALBI score can become part of daily practice.


Assuntos
Bilirrubina/sangue , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/cirurgia , Fígado/efeitos da radiação , Radiocirurgia/métodos , Albumina Sérica/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/mortalidade , Feminino , Humanos , Estimativa de Kaplan-Meier , Testes de Função Hepática , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Radiocirurgia/mortalidade , Estudos Retrospectivos
17.
PLoS One ; 12(5): e0177793, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28545098

RESUMO

OBJECTIVE: To evaluate the survival outcomes and prognostic factors of patients with advanced hepatocellular carcinoma (HCC) who underwent stereotactic ablative radiotherapy (SABR). METHODS: This retrospective study evaluated patients with advanced HCC who underwent SABR between December 2007 and July 2015. All patients had Barcelona Clinic Liver Cancer stage C disease and Child-Turcotte-Pugh (CTP) class A-B function. In-field control (IFC), overall survival (OS), prognostic factors, and toxicity were evaluated. RESULTS: In this study of 89 patients, the 3-year IFC rate was 78.1%, and the 1-year and 3-year OS rates were 45.9% and 24.3%, respectively. The multivariate analysis revealed that CTP class, the presence of main portal vein tumor thrombosis, and the presence of extrahepatic spread were independent predictors of OS. The expected median OS values among patients with ≥2, 1, and 0 predictors were 4.2, 8.6, and 26.4 months, respectively (p <0.001). CONCLUSIONS: SABR may be useful for patients with advanced HCC, and patient selection could be based on the CTP classification, main portal vein tumor thrombosis, and extrahepatic spread.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Radiocirurgia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/mortalidade , Fracionamento da Dose de Radiação , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Radiocirurgia/mortalidade , Estudos Retrospectivos , Análise de Sobrevida
18.
J Radiat Res ; 58(5): 654-660, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28992206

RESUMO

To investigate if dose escalation using intracavitary brachytherapy (ICBT) improves local control for nasopharyngeal carcinoma (NPC) in the era of intensity-modulated radiation therapy (IMRT) and concurrent chemoradiation treatment (CCRT). We retrospectively analyzed 232 patients with Stage T1-3 N0-3 M0 NPC who underwent definitive IMRT with or without additional ICBT boost between 2002 and 2013. For most of the 124 patients who had ICBT boost, the additional brachytherapy was given as 6 Gy in 2 fractions completed within 1 week after IMRT of 70 Gy. CCRT with or without adjuvant chemotherapy was used for 176 patients, including 88 with and 88 without ICBT boost, respectively. The mean follow-up time was 63.1 months. The 5-year overall survival and local control rates were 81.5% and 91.5%, respectively. ICBT was not associated with local control prediction (P = 0.228). However, in a subgroup analysis, 75 T1 patients with ICBT boost had significantly better local control than the other 71 T1 patients without ICBT boost (98.1% vs 85.9%, P = 0.020), despite having fewer patients who had undergone chemotherapy (60.0% vs 76.1%, P = 0.038). Multivariate analysis showed that both ICBT (P = 0.029) and chemotherapy (P = 0.047) influenced local control for T1 patients. Our study demonstrated that dose escalation with ICBT can improve local control of the primary tumor for NPC patients with T1 disease treated with IMRT, even without chemotherapy.


Assuntos
Braquiterapia , Carcinoma/terapia , Quimiorradioterapia , Neoplasias Nasofaríngeas/terapia , Radioterapia de Intensidade Modulada , Carcinoma/tratamento farmacológico , Carcinoma/patologia , Carcinoma/radioterapia , Demografia , Relação Dose-Resposta à Radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/radioterapia , Estadiamento de Neoplasias , Análise de Sobrevida
20.
Radiother Oncol ; 75(2): 204-9, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15908027

RESUMO

BACKGROUND AND PURPOSE: This study examined the efficacy of parotid gland sparing of three-dimensional conformal radiotherapy (3DCRT) compared with conventional radiotherapy for NPC patients. Both the dose given to the parotids and clinical assessment of dry mouth were conducted. MATERIALS AND METHODS: Dry mouth was assessed for 108 patients treated with conventional technique and 72 treated with 3DCRT. Dose analysis was performed in 48 patients of the 3DCRT group. A dose of 70 Gy was given to the midplane in conventional radiotherapy and to 90% isodose volume in 3DCRT. Prognostic factors affecting the severity of dry mouth were analyzed using Generalized Estimating Equation (GEE). RESULTS: In the 3DCRT group about 50% of the patients' parotid glands received less than 25 Gy. Parallel analysis of dry mouth shows a significant decrease in the incidence of severe xerostomia after 3DCRT. The proportion of patients without dry mouth was also significantly higher in the 3DCRT group than the conventional group at 1-3 years after completion of radiotherapy. Although 3DCRT delivered a higher dose to the tumor, it spared the parotid gland significantly better than the conventional treatment. Late toxicities were mostly similar between the 2 groups while local control in T4 patients and survival were improved for 3DCRT. CONCLUSION: Dosimetrically and clinically 3DCRT is better than conventional technique regarding parotid gland protection.


Assuntos
Neoplasias Nasofaríngeas/radioterapia , Glândula Parótida/efeitos da radiação , Lesões por Radiação/prevenção & controle , Radioterapia Conformacional/métodos , Xerostomia/etiologia , Xerostomia/prevenção & controle , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Fracionamento da Dose de Radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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