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1.
Gastric Cancer ; 25(2): 411-421, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34580795

RESUMEN

BACKGROUND: Palliative radiotherapy seems to be rarely performed for incurable gastric cancer. In this first multicenter study, we examined the effectiveness of palliative radiotherapy and investigated whether biologically effective dose (BED) is associated with survival, response, or re-bleeding. METHODS: Eligibility criteria included blood transfusion or hemoglobin levels < 8.0 g/dL. The primary endpoint was the intention-to-treat (ITT) bleeding response rate at 4 weeks. Response entailed all of the following criteria: (i) hemoglobin levels ≥ 8.0 g/dL; (ii) 7 consecutive days without blood transfusion anytime between enrollment and blood sampling; and (iii) no salvage treatment (surgery, endoscopic treatment, transcatheter embolization, or re-irradiation) for bleeding gastric cancer. Re-bleeding was defined as the need for blood transfusion or salvage treatment. RESULTS: We enrolled 55 patients from 15 institutions. The ITT response rates were 47%, 53%, and 49% at 2, 4, and 8 weeks, respectively. The per-protocol response rates were 56%, 78%, and 90% at 2, 4, and 8 weeks, respectively. Neither response nor BED (α/ß = 10) predicted overall survival. Multivariable Fine-Gray model showed that BED was not a significant predictor of response. Univariable Cox model showed that BED was not significantly associated with re-bleeding. Grades 1, 2, 3, and, ≥ 4 radiation-related adverse events were reported in 11, 9, 1, and 0 patients, respectively. CONCLUSIONS: The per-protocol response rate increased to 90% during the 8-week follow-up. The frequent occurrence of death starting shortly after enrollment lowered the ITT response rate. BED was not associated with survival, bleeding response, or re-bleeding.


Asunto(s)
Neoplasias Gástricas , Transfusión Sanguínea , Hemorragia Gastrointestinal/etiología , Hemorragia Gastrointestinal/terapia , Humanos , Cuidados Paliativos/métodos , Dosificación Radioterapéutica , Neoplasias Gástricas/complicaciones , Neoplasias Gástricas/radioterapia
2.
Jpn J Clin Oncol ; 51(6): 950-955, 2021 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-33624768

RESUMEN

BACKGROUND: International guidelines recommend brachytherapy for patients with dysphagia from esophageal cancer, whereas brachytherapy is infrequently used to palliate dysphagia in some countries. To clarify the availability of palliative treatment for dysphagia from esophageal cancer and explain why brachytherapy is not routinely performed are unknown, this study investigated the use of brachytherapy and external beam radiotherapy for dysphagia from esophageal cancer. METHODS: Japanese Radiation Oncology Study Group members completed a survey and selected the treatment that they would recommend for hypothetical cases of dysphagia from esophageal cancer. RESULTS: Of the 136 invited facilities, 61 completed the survey (44.9%). Four (6.6%) facilities performed brachytherapy of the esophagus, whereas brachytherapy represented the first-line treatment at three (4.9%) facilities. Conversely, external beam radiotherapy alone and chemoradiotherapy were first-line treatments at 61 and 58 (95.1%) facilities, respectively. In facilities that performed brachytherapy, the main reason why brachytherapy of the esophagus was not performed was high invasiveness (30.2%). Definitive-dose chemoradiotherapy with (≥50 Gy) tended to be used in patients with expected long-term survival. CONCLUSIONS: Few facilities routinely considered brachytherapy for the treatment of dysphagia from esophageal cancer in Japan. Conversely, most facilities routinely considered external beam radiotherapy. In the future, it will be necessary to optimize external beam radiotherapy.


Asunto(s)
Braquiterapia/métodos , Trastornos de Deglución/etiología , Trastornos de Deglución/terapia , Neoplasias Esofágicas/complicaciones , Cuidados Paliativos/métodos , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/mortalidad , Neoplasias Esofágicas/terapia , Humanos , Japón , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios
3.
J Radiat Res ; 65(3): 408-412, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38718386

RESUMEN

The effectiveness of single-fraction 8-Gy radiotherapy for painful bone metastases has been verified in numerous randomized controlled trials. However, few reports have described the effectiveness of single-fraction 8-Gy radiotherapy in painful tumors other than bone metastases. We conducted a retrospective analysis to evaluate the pain response to single-fraction 8-Gy radiotherapy in painful non-bone-metastasis tumors. We included patients who had received single-fraction 8-Gy radiotherapy for such tumors between January 2017 and December 2022, excluding those with brain metastases, hematological tumors and those who received re-irradiation. Pain response assessment was based on the best responses documented in the medical records and conducted by two radiation oncologists. A total of 36 eligible patients were included in this study. The irradiation sites included primary lesions in eight patients, lymph node metastases in eight, muscle metastases in seven, pleural dissemination in four, skin/subcutaneous metastases in four and other sites in five. Pain response was assessed in 24 patients after radiotherapy. Pain response rate was 88% in evaluable patients; 21 of the 24 patients experienced response. The median assessment date for pain response was 37 days (range: 8-156 days) after radiotherapy. Re-irradiation was performed in four patients (11%). Single-fraction 8-Gy radiotherapy seemed to be a promising treatment option for painful non-bone-metastasis tumors and warrants further investigation.


Asunto(s)
Dolor , Humanos , Masculino , Femenino , Estudios Retrospectivos , Persona de Mediana Edad , Anciano , Adulto , Anciano de 80 o más Años , Dolor/radioterapia , Dolor/etiología , Fraccionamiento de la Dosis de Radiación , Resultado del Tratamiento , Dolor en Cáncer/radioterapia , Dolor en Cáncer/etiología , Neoplasias Óseas/radioterapia , Neoplasias Óseas/secundario , Neoplasias/radioterapia , Neoplasias/patología , Metástasis de la Neoplasia/radioterapia
4.
J Radiat Res ; 65(4): 532-539, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-38923425

RESUMEN

We sought to identify potential evidence-practice gaps in palliative radiotherapy using quality indicators (QIs), previously developed using a modified Delphi method. Seven QIs were used to assess the quality of radiotherapy for bone metastases (BoM) and brain metastases (BrM). Compliance rate was calculated as the percentage of patients for whom recommended medical care was conducted. Random effects models were used to estimate the pooled compliance rates. Of the 39 invited radiation oncologists, 29 (74%) from 29 centers participated in the survey; 13 (45%) were academic and 16 (55%) were non-academic hospitals. For the QIs, except for BoM-4, the pooled compliance rates were higher than 80%; however, for at least some of the centers, the compliance rate was lower than these pooled rates. For BoM-4 regarding steroid use concurrent with radiotherapy for malignant spinal cord compression, the pooled compliance rate was as low as 32%. For BoM-1 regarding the choice of radiation schedule, the compliance rate was higher in academic hospitals than in non-academic hospitals (P = 0.021). For BrM-3 regarding the initiation of radiotherapy without delay, the compliance rate was lower in academic hospitals than in non-academic hospitals (P = 0.016). In conclusion, overall, compliance rates were high; however, for many QIs, practice remains to be improved in at least some centers. Steroids are infrequently used concurrently with radiotherapy for malignant spinal cord compression.


Asunto(s)
Cuidados Paliativos , Indicadores de Calidad de la Atención de Salud , Humanos , Encuestas y Cuestionarios , Neoplasias Encefálicas/radioterapia , Neoplasias Óseas/radioterapia , Neoplasias Óseas/secundario , Radioterapia , Adhesión a Directriz
5.
Ann Med ; 55(1): 2196089, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37043179

RESUMEN

BACKGROUND: Adjuvant durvalumab after chemoradiation has become the standard of care for patients with stage III NSCLC, according to the PACIFIC trial. Whether biomarkers before durvalumab for patients with stage III NSCLC showed predictive and prognostic effects remains unknown. METHODS: This is a retrospective study in the Fujieda Municipal General Hospital between October 2018 and March 2022. We assessed the predictive value of the Prognostic Nutritional Index (PNI) in stage III non-small cell lung cancer (NSCLC) patients treated with durvalumab after chemoradiation. RESULTS: After applying the inclusion and exclusion criteria, the study included 56 patients for further analysis. The median follow-up period was 17.6 months (range, 3.0-45.4 months). According to receiver operating characteristic curve results, the PNI cutoff value to predict overall survival (OS) was 37.9, with sensitivity and specificity at 67.9% and 67.9%. Accordingly, the patients were divided into low- and high-PNI groups. Patients with the low-PNI group had a significantly shorter progression-free survival compared to the high-PNI group (median, 9.1 vs. 21.3 months, p = 0.032). OS was also shorter in the low-PNI group (median, 19.0 months vs. not reached, p < 0.001). In the multivariate Cox hazards regression analyses, the high-PNI was an independent prognostic factor for OS (hazard ratio, 0.187; 95% confidence interval, 0.046-0.760; p = 0.019).It seems that PNI could be used as a predictor for OS in patients with stage III NSCLC treated with durvalumab after chemoradiation.KEY MESSAGESInadequate immunocompetence and nutritional status after chemoradiation therapy may result in poor antitumor efficacy of ICIs.Pretreatment immune and nutritional assessment using PNI could be considered an independent predictor for the survival of stage III NSCLC patients treated with durvalumab after chemoradiation therapy.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Evaluación Nutricional , Pronóstico , Neoplasias Pulmonares/tratamiento farmacológico , Estudios Retrospectivos
6.
Anticancer Res ; 43(10): 4543-4549, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37772575

RESUMEN

BACKGROUND/AIM: Stereotactic radiosurgery (SRS)-used for brain metastases (BMs) with a tumor diameter of ≤2 cm-has a high local control rate, however, it can cause symptomatic radiation-induced brain necrosis. Hypofractionated stereotactic radiation therapy (HFSRT) is not commonly used for such lesions and its effectiveness remains unknown. Herein, the efficacy of 30 Gy 5-fraction HFSRT for treating BMs of <2 cm was retrospectively evaluated. PATIENTS AND METHODS: Patients who received HFSRT and had a gross tumor volume (GTV) of ≤2 cm in maximum diameter were included in the study (49 patients; 179 BMs; median follow-up period, 11.9 months). RESULTS: The mean GTV Peripheral Dose (D95) was 36.2 Gy. The local control (LC) rates at 1 and 2 years were 93.0% and 81.5%, respectively, for all lesions. The 1-year LC rates were 93.6% and 92.0% for ≤1.0-cm and 1.0-2.0-cm lesions, respectively. Multivariate analysis revealed that the only significant difference was in GTV maximal tumor diameter (HR=1.961, p=0.0002). Notably, only one patient had asymptomatic radiation necrosis. CONCLUSION: Owing to the high toxicity of SRS, 5-fraction HFSRT can be an effective treatment strategy for BMs of <2 cm.


Asunto(s)
Neoplasias Encefálicas , Traumatismos por Radiación , Radiocirugia , Humanos , Radiocirugia/efectos adversos , Estudios Retrospectivos , Neoplasias Encefálicas/patología , Resultado del Tratamiento , Traumatismos por Radiación/etiología , Necrosis/etiología
7.
Breast Cancer ; 30(2): 282-292, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36528759

RESUMEN

BACKGROUND: There is a lack of data on combined radiotherapy (RT) and cyclin-dependent kinase 4 and 6 inhibitor (CDK4/6i) risk factors and toxicity. This study aimed to assess the incidence of and risk factors for non-hematologic toxicities in patients treated with combined RT and CDK4/6i using dose-volume parameter analysis. METHODS: We conducted a retrospective multicenter cohort study of patients with metastatic breast cancer receiving RT within 14 days of CDK4/6i use. The endpoint was non-hematologic toxicities. Patient characteristics and RT treatment planning data were compared between the moderate or higher toxicities (≥ grade 2) group and the non-moderate toxicities group. RESULTS: Sixty patients were included in the study. CDK4/6i was provided at a median daily dose of 125 mg and 200 mg for palbociclib and abemaciclib, respectively. In patients who received concurrent RT and CDK4/6i (N = 29), the median concurrent prescribed duration of CDK4/6i was 14 days. The median delivered RT dose was 30 Gy and 10 fractions. The rate of grade 2 and 3 non-hematologic toxicities was 30% and 2%, respectively. There was no difference in toxicity between concurrent and sequential use of CDK4/6i. The moderate pneumonitis group had a larger lung V20 equivalent dose of 2 Gy per fraction and planning target volume than the non-moderate pneumonitis group. CONCLUSIONS: Moderate toxicities are frequent with combined RT and CDK4/6i. Caution is necessary concerning the combined RT and CDK4/6i. Particularly, reducing the dose to normal organs is necessary for combined RT and CDK4/6i.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/patología , Incidencia , Estudios de Cohortes , Inhibidor p18 de las Quinasas Dependientes de la Ciclina/uso terapéutico , Quinasa 4 Dependiente de la Ciclina , Quinasa 6 Dependiente de la Ciclina , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Inhibidores de Proteínas Quinasas/uso terapéutico
8.
Anticancer Res ; 43(6): 2859-2864, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37247919

RESUMEN

BACKGROUND/AIM: Maxillary sinus cancer is a relatively rare disease, and treatment is still evolving. We compared the efficacy of superselective intra-arterial infusion of high-dose cisplatin (CDDP) with concomitant radiotherapy (RADPLAT) using three-dimensional conformal radiotherapy (3DCRT) or intensity-modulated radiotherapy (IMRT) and analyzed the relationship between the total radiation dose and the treatment outcome in localized maxillary sinus cancer. PATIENTS AND METHODS: We reviewed the cases of 58 patients with localized maxillary sinus cancer treated with RADPLAT at our institution from March 2004 to November 2020. These 58 patients included 34 who received 3DCRT and 24 who received IMRT. RESULTS: The median follow-up period was 38.4 months. The median prescribed dose to the local lesion was 66 Gy in the 3DCRT group and 70 Gy in the IMRT group. CDDP (100-120 mg/m2) was administered once a week for a median of 6 cycles. The 5-year local control rate and overall survival rate were 69.9% and 72.2%, respectively. The patients treated with 70 Gy had a significantly higher local control rate (87.7%) than those treated with 60 Gy or less (41.0%) (p=0.011). No late grade 3 or higher eye disorders except for cataracts developed in the IMRT group, while grade 4 eye disorders occurred in four patients receiving 3DCRT. CONCLUSION: IMRT can escalate radiation dose safely with acceptable toxicities. The total dose may have an impact on the local control rate in RADPLAT.


Asunto(s)
Neoplasias del Seno Maxilar , Radioterapia Conformacional , Radioterapia de Intensidad Modulada , Humanos , Cisplatino/efectos adversos , Neoplasias del Seno Maxilar/tratamiento farmacológico , Neoplasias del Seno Maxilar/radioterapia , Radioterapia Conformacional/efectos adversos , Radioterapia Conformacional/métodos , Radioterapia de Intensidad Modulada/efectos adversos , Radioterapia de Intensidad Modulada/métodos , Resultado del Tratamiento , Dosificación Radioterapéutica , Dosis de Radiación , Planificación de la Radioterapia Asistida por Computador
9.
Clin Transl Radiat Oncol ; 42: 100657, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37457019

RESUMEN

Purpose: Although the Palliative Prognostic Index (PPI) has been used to predict survival in various cancers, to our knowledge, no study has examined its applicability in gastric cancer. This study aimed to determine the baseline PPI cutoff value for recommending single-fraction radiotherapy in patients with bleeding gastric cancer. Materials and methods: This was a secondary analysis of the Japanese Radiation Oncology Study Group (JROSG) 17-3, a multicenter prospective study of palliative radiotherapy for bleeding gastric cancer. Discrimination was evaluated using a time-dependent receiver operating characteristic curve, and the optimal cutoff value was determined using the Youden index. A calibration plot was used to assess the agreement between predicted and observed survival. Results: We enrolled 55 patients in JROSG 17-3. The respective median survival times were 6.7, 2.8, and 1.0 months (p = 0.021) for patients with baseline PPI scores of ≤ 2, 2 < PPI ≤ 4, and PPI > 4. The areas under the curve for predicting death within 2, 3, 4, and 5 months were 0.813, 0.787, 0.775, and 0.721, respectively. The negative predictive value was highest when survival < 2 months was predicted and the Youden index was highest when the cutoff PPI value was 2. The calibration curve showed a reasonable agreement between the predicted and observed survival. Conclusion: Baseline PPI is useful for estimating short-term prognosis in patients treated with palliative radiotherapy for gastric cancer bleeding. A cutoff PPI value of 2 for estimating survival ≤ 2 months should be used to recommend single-fraction radiotherapy.

10.
Adv Radiat Oncol ; 8(4): 101205, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37077179

RESUMEN

Purpose: The aim of this study was to understand the income and employment status of patients at the start of and during follow-up after palliative radiation therapy for bone metastasis. Methods and Materials: From December 2020 to March 2021, a prospective multi-institutional observational study was conducted to investigate income and employment of patients at the start of administration of radiation therapy for bone metastasis and at 2 and 6 months after treatment. Of 333 patients referred to radiation therapy for bone metastasis, 101 were not registered, mainly because of their poor general condition, and another 8 were excluded from the follow-up analysis owing to ineligibility. Results: In 224 patients analyzed, 108 had retired for reasons unrelated to cancer, 43 had retired for reasons related to cancer, 31 were taking leave, and 2 had lost their jobs at the time of registration. The number of patients who were in the working group was 40 (30 with no change in income and 10 with decreased income) at registration, 35 at 2 months, and 24 at 6 months. Younger patients (P = 0), patients with better performance status (P = 0), patients who were ambulatory (P = .008), and patients with lower scores on a numerical rating scale of pain (P = 0) were significantly more likely to be in the working group at registration. There were 9 patients who experienced improvements in their working status or income at least once in the follow-up after radiation therapy. Conclusions: The majority of patients with bone metastasis were not working at the start of or after radiation therapy, but the number of patients who were working was not negligible. Radiation oncologists should be aware of the working status of patients and provide appropriate support for each patient. The benefit of radiation therapy to support patients continuing their work and returning to work should be investigated further in prospective studies.

11.
Br J Radiol ; 96(1151): 20230351, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37750858

RESUMEN

OBJECTIVE: To identify factors significantly associated with quality of life (QOL) and determine if these associations are strong enough to predict certain aspects of QOL without measuring them. METHODS: We conducted an exploratory secondary analysis of baseline data of 224 patients (enrolled between December 2020 and March 2021) from a previously published prospective observational study on radiotherapy for bone metastases at 26 centres. Using univariable linear regression, we assessed the association between patient/treatment factors and QOL scale scores as measured by the European Organization for Research and Treatment of Cancer (EORTC) QOL Questionnaire Core 15-Palliative (QLQ-C15-PAL) and the EORTC QOL Questionnaire Bone Metastases module (QLQ-BM22). RESULTS: Age and sex were not significantly associated with QOL. Worse performance status, higher pain scores, and opioid and single-fraction use were significantly associated with most QOL scales; these four factors were associated with worse global QOL, worse functioning status, and more severe symptoms. The coefficients of determination for most QOL scales were less than 0.2, indicating that most of the variability in QOL scores was not explained by any of the explanatory variables. CONCLUSION: Performance status, pain intensity, and opioid and single-fraction use were significantly associated with most QOL scales. However, the associations were not strong enough to estimate QOL. ADVANCES IN KNOWLEDGE: To date, the association between treatment factors and QOL in patients with bone metastases has not been fully studied. We identified the factors that were significantly associated with QOL and found that these associations were not strong enough to predict QOL.


Asunto(s)
Neoplasias Óseas , Calidad de Vida , Humanos , Estudios Transversales , Estudios Prospectivos , Analgésicos Opioides , Neoplasias Óseas/patología , Cuidados Paliativos , Encuestas y Cuestionarios
12.
Exp Physiol ; 97(4): 516-24, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22143884

RESUMEN

Gastric emptying is achieved by co-operation between gastric and duodenal motor activity. Therefore, evaluation of gastric emptying and its associated mechanisms would benefit clinical therapy as well as medical research. Healthy volunteers underwent rapid magnetic resonance imaging (MRI) of the abdomen along the coronal plane after ingestion of a liquid meal. The gastric fundal and duodenal areas were quantified semi-automatically by self-developed segment software. The average gastric fundal area determined by the serosal end in 40 sequential images was reduced to ∼81% 30 min after and to ∼70% 60 min after ingestion of a liquid meal. The average duodenal area also decreased to ∼86% after 30 min and to 83% after 60 min. In contrast, changes in the centre of gravity increased to about fivefold after 30 min and to about threefold after 60 min. The mean velocity of the duodenal wall mimicked changes in the centre of gravity. The application of metoclopramide, a dopamine D(2) receptor antagonist, accelerated gastric emptying, presumably due to facilitated duodenal activity even immediately after liquid meal ingestion. The ingestion of water caused fast gastric emptying in 30 min, accompanied by high duodenal motility, but it ceased after 60 min, presumably reflecting complete gastric emptying. A rapid MRI scan visualized the association between gastric emptying and duodenal motility that could be modified by calories and dopaminergic neurotransmission. Changes in the centre of gravity and mean velocity of the duodenal wall appear to quantify the motility obtained from cine MRI accurately.


Asunto(s)
Bebidas , Duodeno/fisiología , Ingestión de Alimentos/fisiología , Motilidad Gastrointestinal/fisiología , Imagen por Resonancia Magnética/métodos , Vaciamiento Gástrico/fisiología , Humanos , Masculino , Persona de Mediana Edad
14.
Anticancer Res ; 41(2): 919-925, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33517298

RESUMEN

BACKGROUND/AIM: We investigated the dosimetric characteristics of electron radiotherapy for auricular keloid using real-time variable-shape tungsten rubber (STR). PATIENTS AND METHODS: For the first evaluation, STR was shaped into a rectangular irradiation field (3.0×5.0 cm2). In the next step, the STR was reshaped to fit the target (3.5×6.5 cm2) for the second evaluation. Percentage depth doses (PDDs) and lateral dose profiles were obtained with 6-MeV electron beams and compared with those of low-melting-point lead (LML). RESULTS: Compared to the LML on electron applicator, PDD differences were within 0.4 mm, while the penumbras as width of 20-80% dose levels were smaller (maximum reductions: 75.8% and 82.9% at first and second evaluations, respectively). The treatment process of shaping the STR, decision on output, and irradiation was completed within 45 min. CONCLUSION: Electron radiotherapy using STR for keloid can be performed with excellent dose distribution in a short time. First clinical experience found the STR is suitable for use in individualized and immediate electron radiotherapy.


Asunto(s)
Enfermedades del Oído/radioterapia , Queloide/radioterapia , Protección Radiológica/instrumentación , Adulto , Enfermedades del Oído/cirugía , Femenino , Humanos , Queloide/cirugía , Cuidados Posoperatorios , Dosificación Radioterapéutica , Goma , Factores de Tiempo , Tungsteno
15.
Technol Health Care ; 29(2): 253-267, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32568138

RESUMEN

BACKGROUND: The haemodynamics determined by different approaches for studying fluid dynamics - i.e. computational fluid dynamics (CFD), particle image velocimetry (PIV), and phase-contrast magnetic resonance imaging (PC-MRI) - have rarely been thoroughly compared; nor have the factors that affect accuracy and precision in each method. As each method has its own advantages and limitations, this knowledge is important for future studies to be able to achieve valid analyses of fluid flows. OBJECTIVE: To gauge the capacity of these methods for analysing aneurysmal flows, we compared the haemodynamic behaviours determined by each method within a patient-specific aneurysm model. METHODS: An in vitro silicone aneurysm model was fabricated for PIV and PC-MRI, and an in silico aneurysm model with the same geometry was reconstructed for CFD. With the same fluid model prepared numerically and physically, CFD, PIV and PC-MRI were performed to study aneurysmal haemodynamics. RESULTS: 2D velocity vectors and magnitudes show good agreement between PIV and CFD, and 3D flow patterns show good similarity between PC-MRI and CFD. CONCLUSIONS: These findings give confidence to future haemodynamic studies using CFD technology. For the first time, the morphological inconsistency between the PCMRI model and others is found to affect the measurement of local flow patterns.


Asunto(s)
Aneurisma Intracraneal , Velocidad del Flujo Sanguíneo , Simulación por Computador , Hemodinámica , Humanos , Hidrodinámica , Aneurisma Intracraneal/diagnóstico por imagen , Imagen por Resonancia Magnética , Modelos Cardiovasculares , Reología
16.
J Radiat Res ; 62(2): 356-363, 2021 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-33454759

RESUMEN

Evidence regarding postoperative radiation therapy (PORT) for metastases to the long bones is lacking. Characterizing the current practice patterns and identifying factors that influence dose-fractionation schedules are essential for future clinical trials. An internet-based survey of the palliative RT subgroup of the Japanese Radiation Oncology Study Group was performed in 2017 to collect data regarding PORT prescription practices and dose-fractionation schedules. Responders were also asked to recommend dose-fractionation schedules for four hypothetical cases that involved a patient with impending pathological fractures and one of four clinical features (poor prognosis, solitary metastasis, radio-resistant primary tumor or expected long-term survival). Responders were asked to indicate their preferred irradiation fields and the reasons for the dose fractionation schedule they chose. Responses were obtained from 89 radiation oncologists (67 institutions and 151 RT plans) who used 22 dose-fractionation schedules, with the most commonly used and recommended schedule being 30 Gy in 10 fractions. Local control was the most common reason for preferring longer-course RT. High-dose fractionated schedules were preferred for oligometastasis, and low-dose regimens were preferred for patients with a poor prognosis; however, single-fraction RT was not preferred. Most respondents recommended targeting the entire orthopedic prosthesis. These results indicated that PORT using 30 Gy in 10 fractions to the entire orthopedic prosthesis is preferred in current Japanese practice and that single-fraction RT was not preferred. Oligometastasis and poor prognosis influenced the selection of high- or low-dose regimens.


Asunto(s)
Neoplasias Óseas/radioterapia , Neoplasias Óseas/secundario , Pautas de la Práctica en Medicina , Oncología por Radiación , Encuestas y Cuestionarios , Adulto , Anciano , Neoplasias Óseas/cirugía , Fraccionamiento de la Dosis de Radiación , Humanos , Japón/epidemiología , Persona de Mediana Edad
17.
Neuroradiology ; 52(10): 913-20, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19967532

RESUMEN

INTRODUCTION: Hemodynamics is thought to play a very important role in the initiation, growth, and rupture of intracranial aneurysms. The purpose of our study was to compare hemodynamics of intracranial aneurysms of MR fluid dynamics (MRFD) using 3D cine PC MR imaging (4D-Flow) at 1.5 T and MR-based computational fluid dynamics (CFD). METHODS: 4D-Flow was performed for five intracranial aneurysms by a 1.5 T MR scanner. 3D TOF MR angiography was performed for geometric information. The blood flow in the aneurysms was modeled using CFD simulation based on the finite element method. We used MR angiographic data as the vascular models and MR flow information as boundary conditions in CFD. 3D velocity vector fields, 3D streamlines, shearing velocity maps, wall shear stress (WSS) distribution maps and oscillatory shear index (OSI) distribution maps were obtained by MRFD and CFD and were compared. RESULTS: There was a moderate to high degree of correlation in 3D velocity vector fields and a low to moderate degree of correlation in WSS of aneurysms between MRFD and CFD using regression analysis. The patterns of 3D streamlines were similar between MRFD and CFD. The small and rotating shearing velocities and higher OSI were observed at the top of the spiral flow in the aneurysms. The pattern and location of shearing velocity in MRFD and CFD were similar. The location of high oscillatory shear index obtained by MRFD was near to that obtained by CFD. CONCLUSION: MRFD and CFD of intracranial aneurysms correlated fairly well.


Asunto(s)
Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Aneurisma Intracraneal/diagnóstico , Aneurisma Intracraneal/fisiopatología , Angiografía por Resonancia Magnética/métodos , Imagen por Resonancia Cinemagnética/métodos , Anciano , Velocidad del Flujo Sanguíneo , Circulación Cerebrovascular , Simulación por Computador , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Cardiovasculares , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
18.
Neuroradiology ; 52(10): 921-8, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20012431

RESUMEN

INTRODUCTION: Hemodynamics is thought to play a very important role in the initiation, growth, and rupture of intracranial aneurysms. The purpose of our study was to perform in vivo hemodynamic analysis of unruptured intracranial aneurysms of magnetic resonance fluid dynamics using time-resolved three-dimensional phase-contrast MRI (4D-Flow) at 1.5 T and to analyze relationships between hemodynamics and wall shear stress (WSS) and oscillatory shear index (OSI). METHODS: This study included nine subjects with 14 unruptured aneurysms. 4D-Flow was performed by a 1.5-T magnetic resonance scanner with a head coil. We calculated in vivo streamlines, WSS, and OSI of intracranial aneurysms based on 4D-Flow with our software. We evaluated the number of spiral flows in the aneurysms and compared the differences in WSS or OSI between the vessel and aneurysm and between whole aneurysm and the apex of the spiral flow. RESULTS: 3D streamlines, WSS, and OSI distribution maps in arbitrary direction during the cardiac phase were obtained for all intracranial aneurysms. Twelve aneurysms had one spiral flow each, and two aneurysms had two spiral flows each. The WSS was lower and the OSI was higher in the aneurysm compared to the vessel. The apex of the spiral flow had a lower WSS and higher OSI relative to the whole aneurysm. CONCLUSION: Each intracranial aneurysm in this study had at least one spiral flow. The WSS was lower and OSI was higher at the apex of the spiral flow than the whole aneurysmal wall.


Asunto(s)
Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Aneurisma Intracraneal/diagnóstico , Aneurisma Intracraneal/fisiopatología , Angiografía por Resonancia Magnética/métodos , Imagen por Resonancia Cinemagnética/métodos , Anciano , Velocidad del Flujo Sanguíneo , Circulación Cerebrovascular , Simulación por Computador , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Cardiovasculares , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
19.
BMC Cancer ; 9: 408, 2009 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-19930599

RESUMEN

BACKGROUND: Protracted low-dose concurrent chemotherapy combined with radiation has been proposed for enhanced treatment results for esophageal cancer. We evaluated the efficacy and the toxicity of a novel regimen of daily low-dose nedaplatin (cis-diammine-glycolatoplatinum) and continuous infusion of 5-fluorouracil (5-FU) with radiation in patients with esophageal squamous cell carcinoma. METHODS: Between January 2003 and June 2008, 33 patients with clinical stage I to IVB esophageal squamous cell carcinoma were enrolled. Nedaplatin (10 mg/body/day) was administered daily and 5-FU (500 mg/body/day) was administered continuously for 20 days. Fractionated radiotherapy for a total dose of 50.4-66 Gy was administered together with chemotherapy. Additional chemotherapy with nedaplatin and 5-FU was optionally performed for a maximum of 5 courses after chemoradiotherapy. The primary end-point of this study was to evaluate the tumor response, and the secondary end-points were to evaluate the toxicity and the overall survival. RESULTS: Twenty-two patients (72.7%) completed the regimen of chemoradiotherapy. Twenty patients (60.6%) achieved a complete response, 10 patients (30.3%) a partial response. One patient (3.0%) had a stable disease, and 2 (6.1%) a progressive disease. The overall response rate was 90.9% (95% confidence interval: 75.7%-98.1%). For grade 3-4 toxicity, leukopenia was observed in 75.8% of the cases, thrombocytopenia in 24.2%, anemia in 9.1%, and esophagitis in 36.4%, while late grade 3-4 cardiac toxicity occurred in 6.1%. Additional chemotherapy was performed for 26 patients (78.8%) and the median number of courses was 3 (range, 1-5). The 1-, 2- and 3-year survival rates were 83.9%, 76.0% and 58.8%, respectively. The 1- and 2-year survival rates were 94.7% and 88.4% in patients with T1-3 M0 disease, and 66.2% and 55.2% in patients with T4/M1 disease. CONCLUSION: The treatment used in our study may yield a high complete response rate and better survival for each stage of esophageal squamous cell carcinoma. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT00197444.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Escamosas/terapia , Neoplasias Esofágicas/terapia , Fluorouracilo/administración & dosificación , Compuestos Organoplatinos/administración & dosificación , Radioterapia , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Terapia Combinada , Neoplasias Esofágicas/mortalidad , Neoplasias Esofágicas/patología , Femenino , Fluorouracilo/efectos adversos , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Compuestos Organoplatinos/efectos adversos , Resultado del Tratamiento
20.
Radiol Phys Technol ; 11(2): 202-211, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29651683

RESUMEN

We developed a method of velocimetry based on an optical flow method using quantitative analyses of tagged magnetic resonance (MR) images (tagged MR-optical flow velocimetry, tMR-O velocimetry). The purpose of our study was to examine the accuracy of measurement of the proposed tMR-O velocimetry. We performed retrospective pseudo-electrocardiogram (ECG) gating tagged cine MR imaging on a rotating phantom. We optimized imaging parameters for tagged MR imaging, and validated the accuracy of tMR-O velocimetry. Our results indicated that the difference between the reference velocities and the computed velocities measured using optimal imaging parameters was less than 1%. In addition, we performed tMR-O velocimetry and echocardiography on 10 healthy volunteers, for four sections of the heart (apical, midventricular, and basal sections aligned with the short-axis, and a four-chamber section aligned with the long-axis), and obtained radial and longitudinal myocardial velocities in these sections. We compared the myocardial velocities obtained using tMR-O velocimetry with those obtained using echocardiography. Our results showed good agreement between tMR-O velocimetry and echocardiography in the radial myocardial velocities in three short-axial sections and longitudinal myocardial velocities on the midventricular portion of the four-chamber section in the long-axis. In the study conducted on the rotating phantom, tMR-O velocimetry showed high accuracy; moreover, in the healthy volunteers, the myocardial velocities obtained using tMR-O velocimetry were relatively similar to those obtained using echocardiography. In conclusion, tMR-O velocimetry is a potentially feasible method for analyzing myocardial motion in the human heart.


Asunto(s)
Corazón/diagnóstico por imagen , Corazón/fisiología , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética , Movimiento , Fenómenos Ópticos , Femenino , Humanos , Masculino , Fantasmas de Imagen , Adulto Joven
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