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BACKGROUND: New treatment strategies for prostate cancer have recently been developed, but multiple malignancies remain a major concern. The aim of this study was to evaluate the characteristics of multiple malignancies and to analyze the risk of secondary malignancies after radiotherapy for prostate cancer. METHODS: From 2000 to 2011, 150 patients with prostate cancer were treated with curative radiotherapy in our department. Patient age range was 54-92 years (median, 70 years), and the follow-up period was 4-142 months (median, 48 months). The incidence of multiple primary cancers was compared with the estimated incidence. RESULTS: A total of 147 patients (98 %) survived more than 12 months (12-142 months; median, 48 months); 20/150 patients (13 %) died within 10 years. Cause of death was recurrent prostate cancer in 11 patients, other primary malignancies in 7 patients, and cardiovascular disease in 2 patients. Multiple primary cancers were present in 26 of 150 patients (17 %), including 16 subsequent malignancies (11 %) with latent periods of 13-83 months (median, 43 months). The subsequent non-prostate malignancies were lung cancer in 4 patients, urinary bladder or ureter cancer in 4, stomach cancer in 3, malignant lymphoma in 2, and other in 3. Analysis of the observed incidence of secondary malignancies compared with the estimated incidence in the general population revealed a higher incidence of ureter cancer and malignant lymphoma. CONCLUSION: Close attention should be paid to secondary malignancies after radiotherapy for prostate cancer, including malignancies occurring within 5 years, which could be attributable to radiotherapy.
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Neoplasias Primarias Múltiples/patología , Neoplasias Inducidas por Radiación/patología , Neoplasias Primarias Secundarias/patología , Neoplasias de la Próstata/patología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/radioterapia , Estadificación de Neoplasias , Neoplasias Primarias Múltiples/radioterapia , Neoplasias de la Próstata/radioterapia , Radioterapia/efectos adversos , Factores de RiesgoRESUMEN
BACKGROUND: Although pleomorphic adenomas account for over 90% of all benign submandibular gland tumors, the imaging features of submandibular pleomorphic adenomas have not been reported in a large number of cases. PURPOSE: To assess the conventional magnetic resonance imaging (MRI) findings for predicting the submandibular pleomorphic adenoma. MATERIAL AND METHODS: MR studies of 42 pleomorphic adenomas and 28 other types of tumor were reviewed. MR images were assessed for the presence of hyperintense areas on T2-weighted images (first sign), a well-defined margin (second sign), and presence of crescent-shaped compression of the ipsilateral normal submandibular gland (third sign). RESULTS: For identifying submandibular pleomorphic adenoma, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 97.6%, 50.0%, 74.5%, 93.3%, and 78.6% for the first sign, 95.2%, 46.4% 72.7%, 86.7%, and 75.7% for the second sign, and 23.8%, 100%, 86.7%, 46.7%, and 54.3% for the third sign, respectively. Combining the first and second findings achieved to 85.7% specificity and 90.9% accuracy. CONCLUSION: Although non-specific, submandibular pleomorphic adenomas usually have hyperintense areas on T2-weighted images and well-defined margins. In addition, crescent-shaped compression of the ipsilateral normal gland seems to represent a highly specific sign.
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Adenoma Pleomórfico/diagnóstico , Imagen por Resonancia Magnética/métodos , Neoplasias de la Glándula Submandibular/diagnóstico , Adulto , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
UNLABELLED: The value of chemoradiation therapy (CRT) followed by surgery is unknown in Japan. PATIENT AND METHOD: Thirty Patients with TNM cStage II - III squamous cell carcinoma (SCC) of the esophagus were divided into CRT (40 Gy) followed by surgery( arm A) and definitive CRT( 60 Gy()arm B). The correlations between several clinicopathological factors and survival time were examined. RESULTS: The effective rate (CR+PR) of CRT was 75% in arm A versus 88.9% in arm B (p= 0.32). There was no significant difference about the median survival time (arm A: 17. 4 months, arm B: 12. 6 months, p= 0.18). The two-year survival rate was 40 . 4% in arm A versus 41 . 6% in arm B (p=0.35). CONCLUSION: Our retrospective study showed no significant difference in prognosis between CRT followed by surgery and definitive CRT. Definitive CRT might be a choice of therapy for curative esophageal carcinoma.
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Carcinoma de Células Escamosas/terapia , Quimioradioterapia , Neoplasias Esofágicas/terapia , Anciano , Carcinoma de Células Escamosas/patología , Neoplasias Esofágicas/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de NeoplasiasRESUMEN
We reviewed the patients with neoadjuvant chemoradiotherapy (CRT) with S-1 to evaluate the feasibility and effectiveness for locally advanced lower rectal cancer. The CRT regimen consisted of pelvic irradiation (45 Gy in fractions of 1.8 Gy), five days a week. A treatment of oral S-1 (80 mg/m2 per day) on days 1-14 and 22-35 was given during radiotherapy. Patients underwent a curative resection with lateral lymph node resection at 6-8 weeks intervals after neoadjuvant CRT. The response rate on pathological study was 60% (all were grade 2), and no patients had lateral lymph node metastases. Grade 1 or 2 adverse effects occurred in all patients during CRT, but the CRT was achieved in all patients. We found two patients had surgical complications with wound infection and one patient with anastomotic leakage. All complications were improved by conservative treatment. The neoadjuvant CRT was feasible and effective treatment for all patients with locally advanced rectal cancer. We have started a phase II study of the neoadjuvant CRT.
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Antimetabolitos Antineoplásicos/uso terapéutico , Quimioradioterapia , Terapia Neoadyuvante , Ácido Oxónico/uso terapéutico , Neoplasias del Recto/terapia , Tegafur/uso terapéutico , Anciano , Combinación de Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias del Recto/patologíaRESUMEN
BACKGROUND: Hypothyroidism is a common adverse event after radiotherapy for head and neck tumors and the incidence need to be re-evaluated because of using intensity-modulated radiotherapy (IMRT). AIMS/OBJECTIVES: Confirm the dose-volume effect of IMRT for pharyngeal cancer on hypothyroidism. MATERIALS AND METHODS: This was a retrospective analysis of patients underwent IMRT for pharyngeal cancer from June 2011 to May 2018. Patients were classified into group A (thyroid stimulating hormone (TSH) <5µU/ml), group B (5< =TSH < 10), and group C (10< =TSH) based on TSH over 36 months post-radiation. Radiation dose, thyroid volume, and the proportion of the thyroid that received X Gy or greater (Vx) were measured. RESULTS: Fifty-two patients were included in this work. Hypothyroidism developed in 33/52 (63%) patients, 13 in group B and 20 in group C. The mean radiation dose to the thyroid was 49.4 Gy and the median time until hypothyroidism was 39 months after irradiation. Hypothyroidism was significantly related to neck dissection (ND) and radiation dose to the thyroid. Patients whose thyroid received 45 Gy or more (V45) >67% had a significantly higher incidence of hypothyroidism. CONCLUSIONS AND SIGNIFICANCE: Patients with pharyngeal cancer who had ND and V45 to the thyroid >67% are at risk of hypothyroidism.
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Hipotiroidismo/etiología , Neoplasias Faríngeas/radioterapia , Radioterapia de Intensidad Modulada/efectos adversos , Carcinoma de Células Escamosas de Cabeza y Cuello/radioterapia , Glándula Tiroides/efectos de la radiación , Anciano , Terapia Combinada , Relación Dosis-Respuesta en la Radiación , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Disección del Cuello/efectos adversos , Neoplasias Faríngeas/cirugía , Traumatismos por Radiación , Dosificación Radioterapéutica , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello/cirugíaRESUMEN
Treatment strategies for distant organ metastasis have changed markedly since the concept of oligometastasis was introduced. The perception that distant organ metastasis is a systemic disease and not eligible for local therapy is now a thing of the past. Therefore, the present report details a case of postoperative solitary liver metastasis from esophageal squamous cell carcinoma (ESCC), which achieved a clinical complete response to chemotherapy with cisplatin and 5-fluorouracil (5-FU) followed by stereotactic body radiotherapy (SBRT). A 76-year-old male patient underwent esophagectomy for lower thoracic ESCC. At 7 months after surgery, abdominal CT revealed a solitary hypovascular mass, 28 mm in size, in segment 7 of the liver. After three courses of chemotherapy with cisplatin and 5-FU, abdominal CT revealed that the liver mass had shrunk to 7 mm in size. SBRT was then administered with a 6 MV X-ray beam generated by a linear accelerator. A total dose of 50 Gy was given in 5 fractions of 10 Gy to the liver mass. At 1 month after SBRT, abdominal CT revealed that the liver mass had disappeared. The patient received no further adjuvant chemotherapy and had no recurrence at 18 months after diagnosis of liver metastasis and 13 months after SBRT.
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The patient was an 80-year-old woman who was diagnosed with locally advanced low rectal cancer. It was unresectable and we performed chemoradiotherapy combined with S-1 (S-1 80 mg/m2, RT 1.8 Gy × 25, total 45 Gy). An effective reduction of primary region resulted in curative resection (super low anterior resection, D3 lymph node dissection, covering ileostomy) with preserving the anal sphincter. Histopathologically, therapeutic efficacy was Grade 2. Preoperative chemoradiation has been a standard therapy in Western countries and would control local recurrence. This case indicated that CRT could improve a rate of curative resection in patients with locally advanced rectal carcinomas.
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Neoplasias del Recto/terapia , Anciano de 80 o más Años , Antimetabolitos Antineoplásicos/uso terapéutico , Terapia Combinada , Combinación de Medicamentos , Femenino , Humanos , Escisión del Ganglio Linfático , Ácido Oxónico/uso terapéutico , Dosificación Radioterapéutica , Recto/cirugía , Tegafur/uso terapéuticoRESUMEN
This paper describes the ongoing structure of radiation oncology in Japan in terms of equipment, personnel, patient load and geographic distribution to identify and overcome any existing limitations. From March 2013 to August 2016, the Japanese Society for Radiation Oncology conducted a questionnaire based on the Japanese national structure survey of radiation oncology in 2012. Data were analyzed based on the institutional stratification by the annual number of new patients treated with radiotherapy per institution. The estimated annual numbers of new and total (new plus repeat) patients treated with radiation were 213 000 and 251 000, respectively. Additionally, the estimated cancer incidence was 865 238 cases with ~24.6% of all newly diagnosed patients being treated with radiation. The types and numbers of treatment devices actually used included linear accelerator (LINAC; n = 864), telecobalt (n = 0), Gamma Knife (n = 44), 60Co remote afterloading system (RALS; n = 23) and 192Ir RALS (n = 130). The LINAC system used dual-energy functions in 651 units, 3D conformal radiotherapy functions in 759 and intensity-modulated radiotherapy (IMRT) functions in 466. There were 792 Japan Radiological Society/Japanese Society for Radiation Oncology-certified radiation oncologists, 1061.6 full-time equivalent (FTE) radiation oncologists, 2124.2 FTE radiotherapy technologists, 181.3 FTE medical physicists, 170.9 FTE radiotherapy quality managers and 841.5 FTE nurses. The frequency of IMRT use significantly increased during this time. In conclusion, the Japanese structure of radiation oncology has clearly improved in terms of equipment and utility although there was a shortage of personnel in 2012.
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Oncología por Radiación , Encuestas y Cuestionarios , Personal de Salud , Humanos , Japón , Metástasis de la Neoplasia , RadioterapiaRESUMEN
OBJECTIVE: The association between left ventricular (LV) dyssynchrony parameters, given by phase analysis of gated single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI), and acquisition orbits is unclear. The aim of this study was to assess the dependence of LV dyssynchrony parameters on acquisition orbits. METHODS: Ninety-nine patients who underwent 201Tl-gated SPECT MPI were categorized into minor hypoperfusion or major hypoperfusion groups. Forty-four patients who underwent 99mTc-tetrofosmin-gated SPECT MPI were categorized into minor hypoperfusion or major hypoperfusion groups. The major hypoperfusion group with 201Tl was divided into inferior or non-inferior wall hypoperfusion subgroups, and anteroseptal or non-anteroseptal wall hypoperfusion subgroups. Gated SPECT MPI data over a 360° acquisition orbit (360° images) and a 180° acquisition orbit (180° images) were reconstructed, and histogram bandwidth (HBW) and phase standard deviation (PSD) were compared. RESULTS: Between 360° and 180° images with 201Tl, there were significant differences in HBW and PSD both globally (HBW 34.8 ± 16.6 vs. 29.1 ± 10.2; PSD 8.8 ± 4.9 vs. 7.0 ± 2.3, p < 0.05 for both) and in the inferior wall (HBW 29.5 ± 15.5 vs. 23.3 ± 9.0; PSD 7.6 ± 4.6 vs. 5.6 ± 2.4, p < 0.001 for both) in the major hypoperfusion group, and also in the inferior wall in all subgroups of the major hypoperfusion group. In contrast, no segment had any significant differences in HBW or PSD between 360° and 180° images with 99mTc. CONCLUSION: Differences in acquisition orbit had a significant influence on HBW and PSD with 201Tl-gated SPECT MPI in the inferior wall in patients with major hypoperfusion myocardium.
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Imagen de Perfusión Miocárdica , Tomografía Computarizada de Emisión de Fotón Único , Disfunción Ventricular Izquierda/diagnóstico por imagen , Anciano , Tomografía Computarizada por Emisión de Fotón Único Sincronizada Cardíaca , Femenino , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Compuestos Organofosforados/química , Compuestos de Organotecnecio/química , Perfusión , Radiofármacos/química , Tecnecio/química , Radioisótopos de Talio/químicaRESUMEN
PURPOSE: This study aimed to compare the detectability of neoplastic lesion enhancement after gadolinium-based contrast media injection in three-dimensional T1-weighted black blood Cube (3D-T1W BB Cube) and three-dimensional T1-weighted fast spoiled gradient-echo (3D-T1W fast SPGR) images obtained with 1.5-T magnetic resonance imaging (MRI). MATERIALS AND METHODS: Phantom and clinical studies were performed to compare the lesion detectability and contrast ratio (CR) between 3D-T1W BB Cube and 3D-T1W fast SPGR pulse sequences. RESULTS: In the phantom study, the CRs for 3D-T1W BB Cube and 3D-T1W fast SPGR were equivalent at low gadolinium concentrations (0.125-1.25 mmol/l). In the clinical study, the detectability in the two modalities was similar for enhanced lesions ≥5 mm, but was significantly better in 3D-T1W BB Cube for lesions <5 mm (p = 0.011). Similarly, the CRs in both modalities were similar for lesions ≥5 mm (0.66 ± 0.36 vs. 0.56 ± 0.30, p = 0.153), but significantly lower in 3D-T1W BB Cube images for lesions <5 mm (0.29 ± 0.19 vs. 0.39 ± 0.21, p = 0.006). CONCLUSIONS: Contrast 3D-T1W BB Cube imaging appears more sensitive than 3D-T1W fast SPGR imaging for detecting neoplastic lesion enhancement in the clinical setting using a 1.5-T MRI scanner, particularly for lesions <5 mm in diameter.
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Neoplasias Encefálicas/diagnóstico por imagen , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Anciano de 80 o más Años , Medios de Contraste , Femenino , Gadolinio , Humanos , Aumento de la Imagen/métodos , Masculino , Persona de Mediana Edad , Fantasmas de Imagen , Sensibilidad y EspecificidadRESUMEN
Granulocyte colony-stimulating factor (G-CSF)-producing esophageal squamous cell carcinoma (ESCC) is rare. Esophageal cancer is a highly aggressive disease and often spreads hematogenously; however, choroidal metastases are rarely seen. This report detailed an extremely rare case of G-CSF-producing ESCC with choroidal metastasis.
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OBJECTIVE: To examine whether we could predict myocardial ischemia when coronary artery calcification is detected by non-gated multidetector CT in patients with suspected ischemic heart disease. METHODS: Eighty-three patients suspected of having ischemic heart disease (55 men, 28 women; age range 36-83 years; mean age 68 years) underwent multidetector CT and T1-201 single photon emission computed tomography. Prediction of myocardial ischemia by coronary arterial calcification detected on CT was evaluated by comparing the coronary artery territories that showed calcification with the area of myocardial ischemia determined by SPECT. The sensitivity, specificity, positive predictive value, and negative predictive value of multidetector CT for predicting myocardial ischemia were calculated. Coronary angiography was also examined and compared with multidetector CT. Risk factors, including hypertension, smoking, hyperlipidemia, diabetes, and family history, were compared for evidence of coronary artery calcification detected by multidetector CT and myocardial ischemia detected by thallium nuclear scans. RESULTS: For analysis by patients, the sensitivity, specificity, positive predictive value, and negative predictive value of coronary artery calcification for myocardial ischemia detection were 65, 63, 56, and 71%, respectively. Similarly, for analysis by coronary arterial territories, those values were 56, 77, 41 and 86%, respectively. Coronary stenosis on CAG was also related to the ischemia determined by SPECT and calcification on multidetector CT. Ischemia was better influenced by risk factors than was coronary arterial calcification. CONCLUSIONS: For analysis by coronary arterial territories, the specificity and negative predictive value of coronary arterial calcification seen by multidetector CT are relatively high.
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Calcinosis/diagnóstico , Calcinosis/epidemiología , Enfermedad de la Arteria Coronaria/diagnóstico , Enfermedad de la Arteria Coronaria/epidemiología , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/epidemiología , Tomografía Computarizada por Rayos X/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Comorbilidad , Prueba de Esfuerzo/estadística & datos numéricos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Radiofármacos , Reproducibilidad de los Resultados , Medición de Riesgo/métodos , Factores de Riesgo , Sensibilidad y Especificidad , Estadística como Asunto , Talio , Tomografía Computarizada de Emisión de Fotón Único/estadística & datos numéricosRESUMEN
Eighty-one patients with nondisseminated nasopharyngeal carcinoma consecutively treated between January 1977 and December 1998 were analyzed to evaluate whether a concurrent adjunction of low-dose cisplatin enhances the outcome of definitive radiotherapy. Ninety-eight percent (n = 79) of the cases were ranked as stage III/IV according to the 1987 Union International Contre le Cancer staging criteria. Patients treated before 1987 and treated after 1988 were mainly managed by radiotherapy alone (historical group: n = 48) and concurrent chemoradiotherapy with relatively low-dose cisplatin (CCRT group: n = 33), respectively. The locoregional failure-free survival rate of the CCRT group was significantly better than that of the historical group (72.8% vs. 35.9% at 5 years, p = 0.0041). However, multivariate analysis identified only the total dose and the T-stage as significant independent factors for locoregional control. No difference was observed on overall, disease-specific, and distant failure-free survival between the two groups. The results of the present study suggest that concurrent adjunction of low-dose cisplatin will not improve the outcome of definitive radiotherapy for nasopharyngeal carcinoma. Full-dose concurrent chemoradiotherapy, as well as the appropriate dose escalation for better locoregional control, will be mandatory to achieve better survival.
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Antineoplásicos/uso terapéutico , Cisplatino/uso terapéutico , Neoplasias Nasofaríngeas/tratamiento farmacológico , Neoplasias Nasofaríngeas/radioterapia , Fármacos Sensibilizantes a Radiaciones/uso terapéutico , Adulto , Anciano , Terapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Modelos de Riesgos Proporcionales , Dosificación Radioterapéutica , Estudios Retrospectivos , Análisis de Supervivencia , Insuficiencia del TratamientoRESUMEN
Recent developments in diagnostic radiology, which have enabled accurate differential diagnoses of brain tumors, have been well described in the last three decades. MR and PET imaging can also provide information to predict histological grades and prognoses that might influence treatment strategies. However, high-grade astrocytomas consist of many different subtypes that are associated with different imaging and histological characteristics. Hemorrhage and necrosis results in a variety of imaging features, and infiltrative tumor growth entrapping normal neurons may cause different clinical manifestations. We reviewed patients with high-grade astrocytomas that showed various imaging characteristics, with special emphasis on initial symptoms and histological features. Clinicopathological characteristics of astrocytomas were also compared with other malignant tumors. Neurological deficits were not notable in patients with grade 3-4 astrocytomas when they showed infiltrative tumor growth, while brain metastases with compact cellular proliferation caused more neurological symptoms. Infiltrative tumors did not show any enhancing masses on MR imaging, but these tumors may show intratumor heterogeneity. Seizures were reported to be more frequent in low-grade glioma and in secondary glioblastoma. Tumor heterogeneity was also reported in molecular genetic profile, and investigators identified some subsets of astrocytomas. They investigated IHD1/2 mutation, EGFR amplification, TP53 mutation, Ki-67 index, etc. In summary, high-grade astrocytomas are not homogenous groups of tumors, and this is associated with the heterogeneity of clinical manifestation, image characteristics, and histopathological findings. Molecular studies may explain the tumor heterogeneity in the near future.
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Astrocitoma/diagnóstico , Neoplasias Encefálicas/diagnóstico , Astrocitoma/genética , Astrocitoma/patología , Astrocitoma/radioterapia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/radioterapia , Variación Genética , Humanos , Imagen por Resonancia Magnética , Clasificación del Tumor , Tomografía de Emisión de PositronesRESUMEN
BACKGROUND: The aim of this article is to report the treatment outcomes, toxicities, and dosimetric feasibility of our simultaneous-boost intensity-modulated radiotherapy (SIB-IMRT) protocol. METHODS: Thirteen patients with malignant gliomas treated between December 2000 and September 2004 were enrolled in this study. Two planning target volumes (PTVs) were defined in the present study. Our IMRT regimen delivered 70 Gy/28 fractions (fr)/daily; 2.5 Gy to the gross tumor volume (GTV) with a 0.5-cm margin, defined as the PTV-G, and 56 Gy/28 fr/daily, with 2.0 Gy to the surrounding edema, defined as the planning target volume annulus (PTV-a). Eleven of the 13 patients received one or two courses of nimustine hydrochloride (ACNU) (100 mg/m(2)) and vincristine (1.2 mg/body) and interferon-beta (3 x 10(6) units) three times weekly during the period of radiotherapy. Adjuvant chemotherapy, ACNU (100 mg/m(2)) and vincristine (1.2 mg/body), was repeated every 6 weeks and interferon-beta was repeated every 2 weeks. The treatment outcomes, toxicity, and dosimetric feasibility were assessed. RESULTS: All the patients experienced tumor recurrence. The median progression-free survival times for patients with grade III tumors and glioblastome were 7.5 and 8.0 months, respectively. The 1-year and 2-year overall survival rates for all the patients were 77% and 31%, respectively. Four patients experienced acute grade 1/2 toxicities during the treatment. No late toxicity related to radiotherapy has been seen. Analyses with dose-volume histograms confirmed excellent conformity of dose distributions in the two target volumes, PTV-G and PTV-a, with the sparing of organs at risk. CONCLUSION: Our IMRT regimen did not prevent tumor progression. However, the ability of IMRT to deliver highly conformative doses to two contiguous targets, GTV and the surrounding edema, justifies its application to malignant gliomas.
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Neoplasias Encefálicas/radioterapia , Glioma/radioterapia , Radioterapia de Intensidad Modulada , Adulto , Anciano , Neoplasias Encefálicas/mortalidad , Quimioterapia Adyuvante , Femenino , Glioma/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Tasa de Supervivencia , Resultado del TratamientoRESUMEN
BACKGROUND: Intensity-modulated radiotherapy (IMRT) can deliver different doses to two target volumes with high conformity. The purpose of the present study was to compare outcomes provided by two different optimization methods, overlapping structure-based and non-overlapping structure-based methods, for simultaneous integrated boost (SIB)-IMRT for malignant gliomas. METHODS: Treatment plans for three glioblastomas and one anaplastic astrocytoma were analyzed in the present study. The planning protocol was to deliver 70 Gy/28 fractions (fr) to the gross tumor volume (GTV) and 56 Gy/28 fr to the surrounding edema. Two different optimization methods were tested for optimizing dose distribution to the GTVand the surrounding edema. One method was the "including method", an overlapping structure-based (GTV and the clinical target volume [CTV]) optimization method. The other method was the "annulus method", a non-overlapping structure-based (GTV and the subtracted volume) optimization method. Dosimetric indexes derived from dose-volume histograms (DVHs) were used for the analysis. RESULTS: There was no significant difference between the two methods in the mean doses of the target volumes and the doses delivered to the 5% or 95% target volumes (D05 or D95). The mean dose to the brain by the including method was significantly higher than that delivered by the annulus method (P = 0.0001). The D05 of the brain showed no significant difference between the two methods. CONCLUSION: The two optimization methods provided comparable dose distributions within the target volumes and normal brain.