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1.
Clin Oncol (R Coll Radiol) ; 33(3): 191-201, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32768158

RESUMEN

AIMS: About 80% of cases of locally advanced unresectable thoracic oesophageal squamous cell carcinoma recur within the irradiation fields after chemoradiotherapy. Radiation dose escalation using advanced radiotherapy techniques is expected to improve clinical outcomes by reducing local and regional recurrence. The current study aimed to determine the recommended escalated radiation dose for these patients. MATERIALS AND METHODS: Patients with locally advanced unresectable thoracic oesophageal squamous cell carcinoma with good performance status underwent chemoradiotherapy using simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT) with elective nodal irradiation. SIB-IMRT was delivered in five fractions per week. The radiation dose to the unresectable gross tumour was escalated from 66 Gy to a planned maximum dose of 72 Gy in 3 Gy increments in a standard 3 + 3 design. The doses to the resectable component, superficial tumours and elective nodal regions were fixed as 60, 51 and 48 Gy, respectively. Cisplatin and 5-fluorouracil were concurrently administered. Dose-limiting toxicity (DLT) was defined as acute grade 3 oesophagitis, grade 2 pneumonitis, grade 2 cardiac toxicity and a failure to complete planned radiotherapy within 60 days. Locoregional control and overall survival were estimated using the Kaplan-Meier method. Nine patients were enrolled. RESULTS: DLTs occurred in one of six and two of three patients at doses of 66 and 69 Gy, respectively. All DLTs were grade 3 oesophagitis. The recommended dose was determined as 66 Gy delivered in 30 fractions based on the predefined criteria. With a median follow-up period of 23 months, the 1-year locoregional control and overall survival rates were 67 (95% confidence interval = 19-90) and 78% (95% confidence interval = 36-94), respectively. CONCLUSION: The recommended radiation dose in chemoradiotherapy using SIB-IMRT with elective nodal irradiation was 66 Gy delivered in 30 fractions.


Asunto(s)
Quimioradioterapia , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Radioterapia de Intensidad Modulada , Neoplasias Esofágicas/terapia , Carcinoma de Células Escamosas de Esófago/terapia , Humanos , Recurrencia Local de Neoplasia , Dosis de Radiación , Dosificación Radioterapéutica
3.
Med Phys ; 39(6Part18): 3826, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28518485

RESUMEN

PURPOSE: To evaluate a dosimetric accuracy of AcurosXB dose calculation algorithm for 4 MV photon beam. METHODS: Four MV beam (Clinac-6EX) and AAA and AcurosXB algorithms (pre-release version 11.0.03.) were used in this study. The differences of the calculation with AAA (EAAA) and AcurosXB (EAXB) to the measurement were evaluated in the depth doses to 25 cm depth and dose profiles within the water and slab phantoms (water, lung and bone equivalent). In addition, the clinical cases, including three whole breast plans and three head and neck IMRT plans, were evaluated. First the AAA plans were calculated, then AcurosXB plans were recalculated with dose-to-medium with identical beam setup and monitor units as in the AAA plan. RESULTS: In the water phantom study, the EAAA and EAXB were up to 2.2% and 1.5% in the depth doses for the open field (field size = 4 - 40cm square), respectively. Under the heterogeneity conditions, the EAAA and EAXB were less than 4.4% and 2.2% in lung region, and less than 12.5% and 6.3% in bone region, respectively. In the re-buildup region after passing through the lung phantom, the AAA overestimated the doses about 10%; however AcurosXB had good agreement with measurement within 3%. Dose profiles with AcurosXB were better agreement with measurement than AAA. In the clinical cases, the dose of the skin surface region with AcurosXB were higher than AAA by at least 10%, and the dose differences over 5% appeared in heterogeneous region. However, DVH shapes of each organ were similar between AAA and AcurosXB within 2%. CONCLUSIONS: In phantom study, AcurosXB had better agreement to measurement than AAA, especially in heterogeneous region and re-buildup region. In the clinical cases, there were large differences between AcurosXB and AAA in the surface region. Evaluation Agreement of non-clinical versions of Acuros XB with Varian Medical Systems.

4.
Med Phys ; 39(6Part8): 3685, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28518900

RESUMEN

PURPOSE: We have recently developed a dynamic tumor tracking irradiation system using Vero4DRT (MHI-Tm2 000). It is needed to create a 4D correlation model between a fiducial marker implanted near a tumor and an external surrogate as a function of time by continuously acquiring both fluoroscopy images and external surrogate signals. The purpose of this study was to propose a new dosimetry method using Gafchromic XR-SP2 films to measure surface dose by fluoroscopy imaging. METHODS: First, half-value layers (HVLs) were measured using aluminum (Al) thicknesses (15 mm) at 40125 kVp. Subsequently, several films were irradiated using various milliampere second values on a solid water phantom. The surface air kerma were also measured using the chamber to calculate the surface doses under the same condition. Then, the calibration curve of dose vs. pixel values was calculated. Finally, surface dose by fluoroscopy imaging was measured using several pieces of film taped on the chest phantom. Orthogonal X-ray fluoroscopy imaging was simultaneously performed until completion of data acquisition for creating a 4D correlation model. Those films were scanned after irradiation using a flat-bed scanner and converted to dose by calibration curve. RESULTS: The HVLs for tube voltage within 40125 kVp ranged from 2.35 to 5.98 mm Al. The calibration curve between surface dose and pixel values was reasonably smooth. The differences between the measured and the calibrated doses were less than 3%. The hot spots with the maximum dose of 37.12 mGy were observed around the area overlapped by both fluoroscopic fields. CONCLUSIONS: We have proposed a new dosimetry method using Gafchromic XR-SP2 films to measure surface dose by fluoroscopy imaging. This phantom study has demonstrated that it may be feasible to assess surface dose to patients during dynamic tumor tracking irradiation in clinic with ease after further investigation. This research was supported by the Japan Society for the Promotion of Science (JSPS) through its Funding Program for World-Leading Innovation R&D on Science and Technology (FIRST Program). Research sponsored in part by Mitsubishi Heavy Industries, Ltd.

5.
Med Phys ; 39(6Part28): 3972, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28519631

RESUMEN

PURPOSE: To perform the quality assurance for the dynamic tumor-tracking (DTT) irradiation with Vero4DRT (MHI-Tm2 000). METHODS: Vero4DRT swings its gimbaled 6-MV C-band x-ray head along the pan and tilt direction to track a moving tumor. Surrogate signal-based DTT system implemented in Vero4DRT was used. Before DTT irradiation, the correlation model (4D-model) between motion of the IR markers on the abdominal wall and the tumor position was created with synchronously monitoring by the IR camera and orthogonal kV x-ray imaging subsystem. During beam delivery, the 4D-model predicted the future tumor position from the displacement of the IR markers in real-time, and then contentiously transferred the corresponding tracking orientation to the gimbaled x-ray head.Water-equivalent phantoms were set on a 1D motor-driven base with IR markers. A film placed at a depth of 10 cm in the phantom was irradiated under the following conditions: stationary state, and tracking and non- tracking state for sinusoidal patterns. In addition, the geometric accuracy was evaluated using a 3D moving phantom and Polaris Spectra for the previously-acquired patient's respiratory pattern. RESULTS: Compared to the stationary conditions, reductions in lateral distance between 95% doses of the dose profile were 1.2 mm for tracking and 29.6 mm for non-tracking state for (amplitude [A], period [T]) = (20 mm, 2 s); and 0.2 mm and 29.4 mm for (A, T) = (20 mm, 4 s); and 0.0 mm and 11.2 mm for (A, T) = (10 mm, 2 s), respectively. In the geometric accuracy testing, 95th percentile of the tracking error was 0.5 mm in left-right, 1.0 mm in superior-inferior, and 0.5 mm in anterior-posterior direction. CONCLUSIONS: We demonstrated that Vero4DRT substantially reduced the blurring effects on dose distribution with high tracking accuracy, and confirmed the safety of the DTT irradiation for a clinical application. This research was supported by the Japan Society for the Promotion of Science (JSPS) through its Funding Program for World-Leading Innovation R&D on Science and Technology (FIRST Program), and sponsored in part by Mitsubishi Heavy Industries, Ltd.

6.
Phys Med Biol ; 55(1): 1-10, 2010 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-19949261

RESUMEN

The aim of this paper is to assess the overall geometric accuracy of the Novalis system using the Robotic Tilt Module in terms of the uncertainty in frameless stereotactic radiotherapy. We analyzed the following three metrics: (1) the correction accuracy of the robotic couch, (2) the uncertainty of the isocenter position with gantry and couch rotation, and (3) the shift in position between the isocenter and central point detected with the ExacTrac x-ray system. Based on the concept of uncertainty, the overall accuracy was calculated from these values. The accuracy in positional correction with the robotic couch was 0.07 +/- 0.22 mm, the positional shift of the isocenter associated with gantry rotation was 0.35 mm, the positional shift of the isocenter associated with couch rotation was 0.38 mm and the difference in position between the isocenter and the ExacTrac x-ray system was 0.30 mm. The accuracy of intracranial stereotactic radiosurgery with the Novalis system in our clinic was 0.31 +/- 0.77 mm. The overall geometric accuracy based on the concept of uncertainty was 0.31 +/- 0.77 mm, which is within the tolerance given in the American Association of Physicists in Medicine report no. 54.


Asunto(s)
Radiocirugia/instrumentación , Robótica/instrumentación , Algoritmos , Encéfalo/cirugía , Humanos , Modelos Biológicos , Posicionamiento del Paciente , Fantasmas de Imagen , Reproducibilidad de los Resultados , Incertidumbre
7.
Phys Med Biol ; 52(7): 1991-2008, 2007 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-17374923

RESUMEN

An integrated Monte Carlo (MC) dose calculation system, MCRTV (Monte Carlo for radiotherapy treatment plan verification), has been developed for clinical treatment plan verification, especially for routine quality assurance (QA) of intensity-modulated radiotherapy (IMRT) plans. The MCRTV system consists of the EGS4/PRESTA MC codes originally written for particle transport through the accelerator, the multileaf collimator (MLC), and the patient/phantom, which run on a 28-CPU Linux cluster, and the associated software developed for the clinical implementation. MCRTV has an interface with a commercial treatment planning system (TPS) (Eclipse, Varian Medical Systems, Palo Alto, CA, USA) and reads the information needed for MC computation transferred in DICOM-RT format. The key features of MCRTV have been presented in detail in this paper. The phase-space data of our 15 MV photon beam from a Varian Clinac 2300C/D have been developed and several benchmarks have been performed under homogeneous and several inhomogeneous conditions (including water, aluminium, lung and bone media). The MC results agreed with the ionization chamber measurements to within 1% and 2% for homogeneous and inhomogeneous conditions, respectively. The MC calculation for a clinical prostate IMRT treatment plan validated the implementation of the beams and the patient/phantom configuration in MCRTV.


Asunto(s)
Neoplasias de la Próstata/radioterapia , Oncología por Radiación/métodos , Radiometría/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Aluminio/química , Huesos/patología , Humanos , Pulmón/patología , Masculino , Método de Montecarlo , Aceleradores de Partículas , Dosificación Radioterapéutica , Programas Informáticos , Tomografía Computarizada por Rayos X/métodos , Agua/química
8.
Prostate Cancer Prostatic Dis ; 10(3): 288-92, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17160068

RESUMEN

We compared health-related quality-of-life (HRQL) after intensity-modulated radiotherapy (IMRT) with statuses obtained after old and new protocols of three-dimensional conformal radiation therapy (3DCRT) for localized prostate cancer. We measured the general and disease specific HRQL using the MOS 36-Item Health Survey (SF-36), and the University of California, Los Angeles Prostate Cancer Index (UCLA PCI), respectively. IMRT resulted in similar profiles of general and disease-specific HRQL to two other methods within the first year after treatment. Moreover, IMRT gave rise to comparable urinary, intestinal and sexual side effects despite the high dose of radiation applied.


Asunto(s)
Neoplasias de la Próstata/radioterapia , Calidad de Vida , Radioterapia Conformacional/efectos adversos , Radioterapia Conformacional/métodos , Anciano , Humanos , Masculino , Conducta Sexual/efectos de la radiación , Sistema Urinario/efectos de la radiación
9.
Int J Radiat Oncol Biol Phys ; 51(1): 87-93, 2001 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-11516856

RESUMEN

PURPOSE: To evaluate the outcome and adverse effects in patients with osteosarcoma treated with very high-dose definitive intraoperative radiotherapy (IORT), with the intention of saving the affected limb. METHODS AND MATERIALS: Thirty-nine patients with osteosarcoma in their extremities were treated with definitive IORT. The irradiation field included the tumor plus an adequate wide margin and excluded the major vessels and nerves. Forty-five to 80 Gy of electrons or X-rays were delivered. The median follow-up of the surviving patients was 124 months. RESULTS: The cause-specific and relapse-free 5-year survival rate was 50% and 43%, respectively. Distant metastasis developed in 23 patients; 19 died and 4 were alive for >10 years. Nine local recurrences were found 4-29 months after IORT in the affected limb. No radiation-induced skin reaction or nerve palsy was observed in the patients treated with X-rays. Experiments using phantoms also confirmed that the scatter dose was below the toxic level in the IORT setting with X-rays. CONCLUSIONS: Very high-dose definitive IORT combined with preventive nailing and chemotherapy appeared to be a promising quality-of-life-oriented alternative to treating patients with osteosarcomas in the extremities, although the problem of recurrences from the surrounding unirradiated soft tissue remains to be solved.


Asunto(s)
Neoplasias Óseas/radioterapia , Extremidades , Osteosarcoma/radioterapia , Adolescente , Adulto , Neoplasias Óseas/mortalidad , Neoplasias Óseas/patología , Niño , Terapia Combinada , Femenino , Neoplasias Femorales/mortalidad , Neoplasias Femorales/patología , Neoplasias Femorales/radioterapia , Humanos , Húmero , Ilion , Periodo Intraoperatorio , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Osteosarcoma/mortalidad , Osteosarcoma/patología , Dosificación Radioterapéutica , Tibia , Resultado del Tratamiento
10.
Int J Radiat Oncol Biol Phys ; 50(4): 889-98, 2001 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-11429216

RESUMEN

PURPOSE: To evaluate the daily setup accuracy and the reduction of respiratory tumor movement using a body frame in conformal therapy for solitary lung tumor. METHODS AND MATERIALS: Eighteen patients with a solitary lung tumor underwent conformal therapy using a body frame. The body shell of the frame was shaped to the patient's body contour. The respiratory tumor movement was estimated using fluoroscopy, and if it was greater than 5 mm, pressure was applied to the patient's abdomen with the goal of minimizing tumor movement. CT images were then obtained, and a treatment planning was made. A total dose of 40 or 48 Gy was delivered in 4 fractions. Portal films were obtained at each treatment, and the field displacements between them and the simulation films were measured for daily setup errors. The patients were repositioned if the setup error was greater than 3 mm. Correlations were analyzed between patient characteristics and the tumor movement, or the tumor movement reduction and the daily setup errors. RESULTS: Respiratory tumor movement ranged from 0 to 20 mm (mean 7.7 mm). The abdominal press reduced the tumor movement significantly from a range of 8 to 20 mm to a range of 2 to 11 mm (p = 0.0002). Daily setup errors were within 5 mm in 90%, 100%, and 93% of all verifications in left-right, anterior-posterior, and cranio-caudal directions, respectively. Patient repositioning was performed in 25% of all treatments. No significant correlation was detected between patient characteristics and tumor movement, tumor movement reduction, and the daily setup errors. CONCLUSIONS: The abdominal press was successful in reducing the respiratory tumor movement. Daily setup accuracy using the body frame was acceptable. Verification should be performed at each treatment in hypofractionated conformal therapy.


Asunto(s)
Inmovilización , Neoplasias Pulmonares/radioterapia , Radioterapia Conformacional/instrumentación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Fraccionamiento de la Dosis de Radiación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dosificación Radioterapéutica , Respiración
11.
Int J Radiat Oncol Biol Phys ; 49(2): 605-11, 2001 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-11173161

RESUMEN

PURPOSE: To evaluate the usefulness of magnetic resonance (MR) imaging-based radiotherapy treatment planning (RTTP) for bone metastases in clinical applications. METHODS AND MATERIALS: MR imaging-based RTTP was carried out for 28 patients with bone metastases using a permanent magnetic MR unit. Twenty-three patients received MR imaging-assisted X-ray simulation, and five underwent MR simulation. In MR imaging-assisted X-ray simulation, the radiation fields defined by an X-ray simulator were modified based on MR information scanned in the exact treatment position using MR skin markers. In MR simulation, both isocenter position and field size were determined on MR images and projected onto the patient's skin. RESULTS: All lesions unclear on other imaging modalities could be clearly identified on MR imaging. Of the 23 patients receiving MR imaging-assisted X-ray simulation, modification of the original radiation field was necessary in 14 patients (extended in 9, reduced in 4, and completely changed in 1). In MR simulation, appropriate radiation fields could be easily and quickly determined using MR imaging. CONCLUSION: Methods for MR imaging-based RTTP were developed and clinically implemented for patients with bone metastases, and they were shown to be useful for improving the accuracy of the tumor location. They would provide better therapeutic/palliative benefit to particular patients with bone metastases and could also be applied to other lesions in the future.


Asunto(s)
Neoplasias Óseas/radioterapia , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Neoplasias Óseas/diagnóstico por imagen , Neoplasias Óseas/secundario , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X
12.
Radiother Oncol ; 57(2): 237-42, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11054528

RESUMEN

BACKGROUND AND PURPOSE: Image distortion is one of the major drawbacks of magnetic resonance (MR) imaging for use in radiotherapy treatment planning (RTTP). In this study, the reproducibility of MR imaging distortion was evaluated by repeated phantom measurements. MATERIALS AND METHODS: A grid-pattern acrylic phantom was scanned with a 0.2-Tesla permanent magnetic unit. We repeated a series of scans three times to evaluate the reproducibility of the distortion. In each series, co-ordinates at 432 intersections of the grid were measured for both T1- and T2-weighted spin-echo (SE) pulse sequences. Positional displacements and their variations at the intersections were calculated. RESULTS: Averages of the displacements were distributed between 1.58 and 1.74 mm, and maximum values (MAX) between 12.6 and 15.0 mm. Within 120 mm of the image center, the average values ranged from 0.73 to 0.80 mm, and from 3.4 to 5.0 mm for MAX. The absolute values of the positional variations among three series were distributed between 0.41 and 0.88 mm for average values, and between 1.4 and 4.5 mm for MAX. CONCLUSIONS: The positional variations were mostly within 3 pixels, and most of the positional displacements within the radius of 120 mm of the image center were 2 mm or less. Therefore, it will be possible to use this MR system in RTTP under limited situations, although careful applications are required for RTTP of the body. The development of a computer program to correct image distortion is expected.


Asunto(s)
Artefactos , Aumento de la Imagen/métodos , Imagen por Resonancia Magnética/instrumentación , Fantasmas de Imagen , Planificación de la Radioterapia Asistida por Computador/métodos , Diseño de Equipo , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
13.
Dis Esophagus ; 13(1): 80-6, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11005338

RESUMEN

We have been treating patients with operable thoracic esophageal cancer according to our own protocol. It includes the initial concurrent chemoradiotherapy (CRT) followed by continuous CRT or surgery. Patients with good response to initial chemoradiotherapy were allowed to continue chemoradiotherapy, whereas the others were treated with surgery. However, there were two cases which showed discrepancies in the clinicopathological response. Both patients received initial chemoradiotherapy, including two courses of cisplatin (100-120 mg), 5-fluorouracil (750-1000 mg for 4 days) and radiation (44-50 Gy). On completion of the initial chemoradiotherapy, all diagnostic imaging modalities including barium swallow, esophagoscopy, endoscopic ultrasonography and thoracic computed tomography strongly implicated residual tumor with a reduction rate of 40-50%. The patients underwent radical esophagectomy 15-20 days after initial chemoradiotherapy. Pathological specimens only revealed thickening of the esophageal wall due to inflammatory change without residual carcinoma. These facts suggest the current limitations of diagnostic images in evaluating the response to chemoradiotherapy.


Asunto(s)
Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/radioterapia , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/radioterapia , Anciano , Carcinoma de Células Escamosas/patología , Terapia Combinada , Neoplasias Esofágicas/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Inducción de Remisión , Resultado del Tratamiento
14.
Int J Radiat Oncol Biol Phys ; 45(2): 277-84, 1999 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-10487546

RESUMEN

PURPOSE: This retrospective study was designed to compare treatment results of the chemoradiation protocol with conventional surgery for thoracic T1-T2 esophageal squamous cell carcinoma. METHODS AND MATERIALS: Sixty-six patients with esophageal carcinoma, clinically diagnosed as T1 (tumor invading lamina propria or submucosa) or T2 (tumor invading muscularis propria) were treated for 12 consecutive years, from July 1986 to January 1998. The conventional surgery group included 30 patients who underwent esophagectomy with regional lymph node dissection. Twenty-one of them received postoperative radiotherapy. Thirty-six patients were assigned to the chemoradiation protocol, consisting of neoadjuvant chemoradiotherapy (44 Gy; CDDP: 60 mg/m2, day 1, bolus; 5-FU: 400 mg/m2, day 1-4, continuous), followed by either definitive radiotherapy with high-dose-rate intraluminal brachytherapy (total 70 Gy) for responders or surgery for nonresponders as in the conventional surgery group. Surgical candidates in both groups received intraoperative radiotherapy for abdominal lymphatics since 1991. RESULTS: In the protocol group, 4 patients underwent radical surgery after neoadjuvant chemoradiotherapy, and the remaining 32 underwent definitive chemoradiotherapy. Local control rates at 1 and 3 years were 85% and 70% in the T1/protocol group versus 91% and 80% in the T1/surgery group, and 83% and 83% in the T2/protocol group versus 94% and 80% in the T2/surgery group, respectively. There was no statistical significance. Overall 1- and 3-year survival rates were 100% and 83% in the T1/protocol group versus 82% and 72% in the T1/surgery group (p = 0.36), and 100% and 51% in the T2/protocol group, versus 95% and 68% in the T2/surgery group p = 0.61), respectively. There was no treatment-related mortality in either group. The rates of esophageal conservation were 92% in the T1/protocol group and 58% in the T2/protocol group. CONCLUSION: The chemoradiation protocol can result in comparable survival with conventional surgery for patients with T1-T2 esophageal carcinoma. A randomized trial between definitive chemoradiotherapy and surgery is required.


Asunto(s)
Carcinoma de Células Escamosas/terapia , Neoplasias Esofágicas/terapia , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Causas de Muerte , Cisplatino/administración & dosificación , Terapia Combinada , Neoplasias Esofágicas/mortalidad , Neoplasias Esofágicas/patología , Femenino , Fluorouracilo/administración & dosificación , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Dosificación Radioterapéutica , Estudios Retrospectivos , Tasa de Supervivencia
15.
Radiother Oncol ; 50(2): 151-6, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10368038

RESUMEN

PURPOSE: To assess errors resulting from manual transfer of contour information for three-dimensional (3-D) target reconstruction, and to determine variations in target volume delineation of brain tumours by different radiation oncologists. MATERIALS AND METHODS: Images of 18 patients with intracranial astrocytomas were used for retrospective treatment planning by five radiation oncologists. In this study, the target outline was delineated on sequential CT slices by an experienced radiation oncologist. Thereafter, the target outline was manually reconstructed by five radiation oncologists onto an A-P or lateral scout film. The same target outline was also reconstructed as a projection using the Beam's-eye view capability on a CT simulator unit. The two target outlines were compared by encompassing each shape with the smallest rectangle. The manually-reconstructed radiation field was termed 'Field manually established on X-ray film (F-X)', and the automatically-established field was termed 'Field established by CT simulator (F-CT)'. In a second part of this study, four radiation oncologists defined contours from contrast enhanced CT images of nine patients with intracranial astrocytomas. The CT images of these nine cases included five pre-operative cases and four post-operative cases. Both gross tumour volume (GTV) and clinical target volume (CTV) were outlined on sequential CT slices. The target outlines for the four radiation oncologists were compared by identifying the smallest rectangular field surrounding the projection of these contours. The field established by each radiation oncologist was termed 'Field of target volume (F-TV)', and the overlapping portion of the four F-TVs for each case was termed 'Overlapped field of the target volume (Fo-TV)'. RESULTS: The average distance between the isocentres of F-X and F-CT was 0.6 +/- 0.4 cm (mean +/- SD). The average ratio of the area of F-X divided by the area of F-CT was 1.04 +/- 0.12. The area of F-X was wider than the area of F-CT for four of the five oncologists. The ratio of the area of F-TV divided by the area of Fo-TV was calculated. The average ratio was relatively greater for CTV (2.07 in pre-operative cases and 2.11 in post-operative cases) than for GTV (1.12 in pre-operative cases and 1.41 in post-operative cases). Among radiation oncologists, variations in the delineation of GTV were smaller than those of CTV. CONCLUSIONS: When using an X-ray simulator in treatment planning, errors resulting from the manual transfer of CT contour information to planar radiographs must be considered. When computer techniques are used to project contours onto radiographs errors resulting from individual variations when performing the contouring must be considered.


Asunto(s)
Astrocitoma/diagnóstico por imagen , Neoplasias Encefálicas/diagnóstico por imagen , Planificación de la Radioterapia Asistida por Computador/métodos , Tomografía Computarizada por Rayos X , Astrocitoma/radioterapia , Neoplasias Encefálicas/radioterapia , Humanos , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados
16.
Am J Clin Oncol ; 22(1): 97-102, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10025392

RESUMEN

The effects of transcatheter intraarterial infusion of anticancer drugs on the prognosis of cervical cancer were retrospectively studied. Two or three sessions of transcatheter arterial infusion therapy were performed for 68 patients with primary uterine cervical cancer. The number of patients with stage I, II, III, or IV disease were 13, 22, 24, and 9, respectively. Patients with squamous cell carcinoma comprised 3, 17, 17, and 5 of the respective groups, and the patients with stage I and II disease had either adenocarcinoma or adenosquamous carcinoma, or bulky tumor (>4 cm). The drugs infused were cisplatin (60-70 mg/m2), doxorubicin hydrochloride (30-40 mg/m2), mitomycin (15 mg/m2), and 5-fluorouracil (500 mg/body). They were infused via the bilateral internal iliac arteries. Fifty-eight of the 68 patients (85%) received a radical hysterectomy after transcatheter arterial infusion: 12 of 13 with stage I disease, 21 of 22 with stage II disease, 20 of 24 with stage III disease, and five of nine with stage IV disease. Two patients with stage III disease received radical radiotherapy. The other eight patients (one with stage I disease, one with stage II disease, two with stage III disease, and four with stage IV disease) did not receive an operation after transcatheter arterial infusion because they had distant metastases at the time of operation. Thirty-two of 58 patients (56%) received postoperative radiotherapy. The complete histologic response rates (no active cancer cells) after transcatheter arterial infusion were: 2 of 12 patients with stage I disease, 3 of 21 patients with stage II disease, 5 of 20 patients with stage III disease, and one of five patients with stage IV disease. Tumors with squamous cell carcinoma disappeared at a significantly better rate (10/36, 28%) than did tumors with adenocarcinoma or adenosquamous cell carcinoma (1/22, 5%; p < 0.05). The overall 5-year survival rates of the patients with stages I, II, and III disease were 92.3%, 62.2%, and 71%, respectively. The 5-year survival rates of the patients who underwent surgery with stage I, II, and III disease were 100%, 66.3%, and 71.5%, respectively. Leukocytopenia and thrombocytopenia occurred as an acute complication in 75% and 79% of the patients, respectively. As a late complication, ileus occurred in 7%. Transcatheter arterial infusion may improve the prognosis of patients with cervical cancer without increasing the incidence of late complications.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Infusiones Intraarteriales , Neoplasias del Cuello Uterino/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Terapia Combinada , Femenino , Humanos , Histerectomía , Arteria Ilíaca , Imagen por Resonancia Magnética , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Análisis de Supervivencia , Neoplasias del Cuello Uterino/patología
17.
Radiat Med ; 17(6): 459-62, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10646987

RESUMEN

A 51-year-old man with increasing dysphasia was admitted to our hospital on March 18, 1985. Several examinations revealed thoracic esophageal squamous cell carcinoma 11 cm in length staged T3N0M0 (stage IIA) by UICC 1987. As he rejected our proposal of surgery, definitive radiotherapy (60 Gy) was delivered, and complete response was obtained. The patient had been doing well for 5 years after radiotherapy until superficial local recurrence was discovered at a periodic endoscopic examination. High-dose-rate intraluminal brachytherapy (10 Gy/2 Fr) was administered. After a 3-year disease-free interval, superficial recurrence developed in the same location, and early gastric cancer was detected as a secondary cancer. Radical salvage surgery was performed. The patient was alive and disease free 5 years and 5 months after surgery. We present this rare case of a patient who survived 14 years after the initial radiotherapy. The present case demonstrated the importance of long-term follow-up after radiotherapy, long-term local controllability of relatively low doses of intraluminal brachytherapy after superficial recurrence, and the feasibility of salvage surgery as long as local recurrence is limited to within the mucosal layer.


Asunto(s)
Carcinoma de Células Escamosas/radioterapia , Neoplasias Esofágicas/radioterapia , Recurrencia Local de Neoplasia/cirugía , Carcinoma de Células Escamosas/diagnóstico por imagen , Carcinoma de Células Escamosas/secundario , Carcinoma de Células Escamosas/cirugía , Neoplasias Esofágicas/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico por imagen , Radiografía , Terapia Recuperativa , Neoplasias Gástricas/secundario
18.
Dis Esophagus ; 12(4): 270-5, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10770361

RESUMEN

We applied intraoperative radiotherapy (IORT) to the esophageal carcinoma in an attempt to prevent abdominal lymph node recurrence, and retrospectively studied patterns of failure and controllability of abdominal lymph nodes in patients treated with or without IORT. Between July 1986 and October 1997, 81 patients with radically resected esophageal carcinoma, aged 42-76 years (mean 61), were divided into two groups, the IORT group (39 patients) and the non-IORT group (42 patients). All patients except two, who received transhiatal esophagectomy for superficial carcinoma, underwent subtotal esophagectomy with thoracic and abdominal with/without cervical lymphadenectomy. Fourteen patients underwent only surgical resection, and the remaining 67 patients received radiotherapy to the mediastinum post-operatively (40-50 Gy/20-25 Fr/4-5 W) in 37 and preoperatively (44 Gy/40 Fr/4 W) in 30 patients. Preoperative irradiation was performed as a neoadjuvant chemoradiotherapy consisting of two courses of cisplatin (each patient received 80-100 mg, mean 60 mg m(-2), day 1, bolus injection) and 5-fluorouracil (each patient received 500-1000 mg day(-1), mean 400 mg m(-2), days 1-4, continuous infusion). The target volume of IORT encompassed the upper abdominal lymph node area including lymph node groups of right/left cardia, left gastric artery, celiac artery and abdominal para-aorta. A single dose of high-energy electrons (9-12 MeV) of 20-23 Gy, prescribed to the 90% isodose curve, was delivered. Treatment for the abdominal lymphatic system was classified into four categories: surgery alone in 30 patients, surgery with chemotherapy in 12, surgery with IORT in 15, surgery with chemotherapy and IORT in 24. There were no complications related to IORT. Forty patients (49%) had recurring carcinoma: in the lymph nodes (36%), in distant organs (27%) and locally (6%). The incidence of lymph node metastasis was 29% in the neck, 32% in the mediastinum, and 27% in the abdomen. Abdominal lymph node recurrence in the IORT group was less frequent than in the non-IORT group (p=0.048). In particular, 24 patients treated with a combination of surgery, chemotherapy and IORT had no recurrence in the abdominal lymphatic system. The overall median survival was 46 months, the survival at 1, 3, and 5 years being 85%, 52%, and 44% respectively. However, there was no difference in survival between the IORT group and the non-IORT group. The IORT for the abdominal lymphatic system was feasible for reduction of the rate of abdominal lymphatic recurrence without survival benefit in this study. This retrospective finding should be confirmed by a prospective randomized study.


Asunto(s)
Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirugía , Neoplasias Esofágicas/radioterapia , Neoplasias Esofágicas/cirugía , Cuidados Intraoperatorios/métodos , Metástasis Linfática/radioterapia , Adulto , Anciano , Distribución de Chi-Cuadrado , Supervivencia sin Enfermedad , Esofagectomía/métodos , Femenino , Humanos , Metástasis Linfática/prevención & control , Masculino , Persona de Mediana Edad , Probabilidad , Pronóstico , Dosis de Radiación , Radioterapia Adyuvante , Estudios Retrospectivos , Estadísticas no Paramétricas , Tasa de Supervivencia , Resultado del Tratamiento
19.
Cardiovasc Intervent Radiol ; 21(3): 205-7, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9626435

RESUMEN

PURPOSE: To evaluate the effect of transcatheter arterial embolization (TAE) on metastatic bone tumors in an experimental study. METHODS: Fifteen Japanese white rabbits were transplanted with VX2 sarcoma cells into the iliac crest. In 10 rabbits, the arterial supply to the iliac bone tumors, internal iliac artery and iliolumbar artery were then embolized with particles of gelatin sponge. The therapeutic effect was evaluated by comparison with the natural course of control tumors in the other five rabbits. RESULTS: After TAE, extensive necrosis, fibrosis, and vacuolization within the tumors were confirmed histologically. In the control rabbits, 19% +/- 7% of the entire tumor was found to be spontaneous tumor necrosis; in contrast, the tumors of the TAE group showed necrosis as 62% +/- 22% of the entire tumor. In one TAE group rabbit, no active tumor cell could be detected in the residual tumor. CONCLUSION: TAE was found to be an effective treatment for bone tumors in an experimental model.


Asunto(s)
Neoplasias Óseas/terapia , Embolización Terapéutica/métodos , Sarcoma Experimental/terapia , Neoplasias de los Tejidos Blandos/terapia , Animales , Neoplasias Óseas/patología , Neoplasias Óseas/secundario , Esponja de Gelatina Absorbible/uso terapéutico , Ilion/patología , Conejos , Sarcoma Experimental/patología , Neoplasias de los Tejidos Blandos/patología , Estadísticas no Paramétricas
20.
Cardiovasc Intervent Radiol ; 21(3): 208-13, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9626436

RESUMEN

PURPOSE: To evaluate the clinical effects of transcatheter arterial embolization (TAE) on malignant bone and soft tissue tumors. METHODS: TAE was performed in 10 patients with primary bone and soft tissue sarcomas and in 31 patients with metastatic bone tumors. The embolized arteries were the internal iliac artery in 30 cases, the intercostal artery in six cases, the lumbar artery in five cases, the suprascapular artery in three cases, and the iliolumbar artery, the internal pudendal artery, and the lateral sacral artery in one case each. The embolized material was gelatin sponge particles. The chemotherapeutic drugs were usually 20-40 mg of doxorubicin for primary and metastatic tumors and 50-100 mg of cisplatin only for primary tumors. In addition, 50-60 Gy of 10-MV radiotherapy with or without radiofrequency (RF)-capacitive hyperthermia in four sessions was administered before TAE for primary tumors only. RESULTS: Even though the pain score increased immediately after TAE, 30 of 38 (79%) patients with pain (8 of 9 with primary tumors, and 22 of 29 with metastases) achieved pain control after TAE. A necrotic low-density area shown by computed tomography (CT) after TAE was found in 31 of 41 (76%) tumors [8 of 10 (80%) with primary tumors, and 23 of 31 (74%) with metastatic tumors]. The tumor size decreased in 14 of 25 (56%) primary and metastatic tumors after 3 months. Osteosclerotic changes appeared in two cases of metastatic tumors after 6 months. In five tumors resected after TAE, large areas of necrosis within the tumor were confirmed histologically. Transient local pain and numbness appeared after TAE, but were relieved by drug treatment within 1 week. No severe complications except a case of gluteal muscle necrosis were encountered after TAE. The 1-year survival rate of the patients with primary tumors was 38.1%, and the median survival was 18 months. The longest survival was 84 months. The 1-year survival rate of the patients with metastatic bone tumors was 38.9%; the median survival was 12 months. The longest survival was 24 months. CONCLUSION: TAE could be an effective treatment for pain control and local control of malignant bone and soft-tissue tumors.


Asunto(s)
Neoplasias Óseas/terapia , Embolización Terapéutica/métodos , Sarcoma/terapia , Neoplasias de los Tejidos Blandos/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Óseas/secundario , Terapia Combinada , Embolización Terapéutica/efectos adversos , Estudios de Evaluación como Asunto , Femenino , Esponja de Gelatina Absorbible/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Tasa de Supervivencia
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