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1.
Sci Rep ; 12(1): 13011, 2022 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-35906266

RESUMEN

Massive boulders in landslide and tsunami deposits are prominent geomorphic features in various landscapes. Tracking their movement history is important for reconstructing past geologic dynamics; however, the reworking movements of massive boulders remain unresolved. The boulder field on the Ishigaki Island was formed by repeated tsunamis. Although the individual movement histories of boulders contribute to retrodict the history of different magnitude tsunamis, their radiocarbon ages only correspond to the tsunamis that detached boulders from the reef. Viscous remanent magnetization dating methods have been applied in reworking movements. These methods reveal signals associated with remanent magnetization that gradually grew since the reworking event, which helps to determine the passage of time. The methods were verified by comparison to the radiocarbon ages of un-reworked boulders detached by the recent Meiwa tsunami, while the estimated ages of such two boulders based on the classical relaxation theory contradicted the radiocarbon ages. Here, we show that a method based on the stretched exponential function addressed this contradiction. The reworking movement was estimated using an additional boulder, whose, using our method, radiocarbon age indicated that an older tsunami moved it, whereas the remanent magnetization age unveiled a reworking of the boulder attributed to the Meiwa tsunami.


Asunto(s)
Datación Radiométrica , Tsunamis
2.
J Radiat Res ; 62(3): 525-532, 2021 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-33823010

RESUMEN

We aimed to compare the outcomes of high-dose-rate brachytherapy (HDR-BT) boost and external beam radiation therapy (EBRT) alone for high-risk prostate cancer. This was a single-center, retrospective and observational study. Consecutive patients who underwent initial radical treatment by HDR-BT boost or EBRT alone from June 2009 to May 2016 at the Niigata University Medical and Dental Hospital, Japan were included. A total of 96 patients underwent HDR-BT boost, and 61 underwent EBRT alone. The prescription dose of HDR-BT boost was set to 18 Gy twice a day with EBRT 39 Gy/13 fractions. The dose for EBRT alone was mostly 70 Gy/28 fractions. The high-risk group received >6 months of prior androgen deprivation therapy. Overall survival, biochemical-free survival, local control and distant metastasis-free survival rates at 5 years were analyzed. The incidence of urological and gastrointestinal late adverse events of Grade 2 and above was also summarized. In the National Comprehensive Cancer Network (NCCN) high-risk calssification, HDR-BT boost had a significantly higher biochemical-free survival rate at 5 years (98.9% versus 90.7%, P = 0.04). Urethral strictures were more common in the HDR-BT boost group. We will continuously observe the progress of the study patients and determine the longer term results.


Asunto(s)
Braquiterapia , Neoplasias de la Próstata/radioterapia , Anciano , Anciano de 80 o más Años , Antagonistas de Andrógenos/uso terapéutico , Relación Dosis-Respuesta en la Radiación , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Próstata/tratamiento farmacológico , Factores de Riesgo
3.
Radiol Phys Technol ; 14(1): 57-63, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33393057

RESUMEN

Through geometrical simulation, we evaluated the effect of rotational error in patient setup on geometrical coverage and calculated the maximum distance between the isocenter and target, where the clinical PTV margin secures geometrical coverage with a single-isocenter technique. We used simulated spherical GTVs with diameters of 1.0 (GTV 1), 1.5 (GTV 2), 2.0 (GTV 3), and 3.0 cm (GTV 4). The location of the target center was set such that the distance between the target and isocenter ranged from 0 to 15 cm. We created geometrical coverage vectors so that each target was entirely covered by 100% of the prescribed dose. The vectors of the target positions were simultaneously rotated within a range of 0°-2.0° around the x-, y-, and z-axes. For each rotational error, the reduction in geometrical coverage of the targets was calculated and compared with that obtained for a rotational error of 0°. The tolerance value of the geometrical coverage reduction was defined as 5% of the GTV. The maximum distance that satisfied the 5% tolerance value for different values of rotational error at a clinical PTV margin of 0.1 cm was calculated. When the rotational errors were 0.5° for a 0.1 cm PTV margin, the maximum distances were as follows: GTV 1: 7.6 cm; GTV 2: 10.9 cm; GTV 3: 14.3 cm; and GTV 4: 21.4 cm. It might be advisable to exclude targets that are > 7.6 cm away from the isocenter with a single-isocenter technique to satisfy the tolerance value for all GTVs.


Asunto(s)
Neoplasias Encefálicas , Radiocirugia , Neoplasias Encefálicas/cirugía , Simulación por Computador , Humanos , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador
4.
J Appl Clin Med Phys ; 21(12): 288-294, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33270984

RESUMEN

PURPOSE: The interruption time is the irradiation interruption that occurs at sites and operations such as the gantry, collimator, couch rotation, and patient setup within the field in radiotherapy. However, the radiobiological effect of prolonging the treatment time by the interruption time for tumor cells is little evaluated. We investigated the effect of the interruption time on the radiobiological effectiveness with photon beams based on a modified microdosimetric kinetic (mMK) model. METHODS: The dose-mean lineal energy yD (keV/µm) of 6-MV photon beams was calculated by the particle and heavy ion transport system (PHITS). We set the absorbed dose to 2 or 8 Gy, and the interruption time (τ) was set to 1, 3, 5, 10, 30, and 60 min. The biological parameters such as α0, ß0, and DNA repair constant rate (a + c) values were acquired from a human non-small-cell lung cancer cell line (NCI-H460) for the mMK model. We used two-field and four-field irradiation with a constant dose rate (3 Gy/min); the photon beams were paused for interruption time τ. We calculated the relative biological effectiveness (RBE) to evaluate the interruption time's effect compared with no interrupted as a reference. RESULTS: The yD of 6-MV photon beams was 2.32 (keV/µm), and there was little effect by changing the water depth (standard deviation was 0.01). The RBE with four-field irradiation for 8 Gy was decreased to 0.997, 0.975, 0.900, and 0.836 τ = 1, 10, 30, 60 min, respectively. In addition, the RBE was affected by the repair constant rate (a + c) value, the greater the decrease in RBE with the longer the interruption time when the (a + c) value was large. CONCLUSION: The ~10-min interruption of 6-MV photon beams did not significantly impact the radiobiological effectiveness, since the RBE decrease was <3%. Nevertheless, the RBE's effect on tumor cells was decreased about 30% by increasing the 60 min interruption time at 8 Gy with four-field irradiation. It is thus necessary to make the interruption time as short as possible.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Simulación por Computador , Humanos , Neoplasias Pulmonares/radioterapia , Método de Montecarlo , Efectividad Biológica Relativa
5.
Cancers (Basel) ; 12(10)2020 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-33066141

RESUMEN

This study investigated the efficacy and safety of radiotherapy as part of multidisciplinary therapy for advanced hepatocellular carcinoma (HCC). Clinical data of 49 HCC patients treated with radiotherapy were assessed retrospectively. The efficacy of radiotherapy was assessed by progression-free survival, disease control rate, and overall survival. Safety was assessed by symptoms and hematological assay, and changes in hepatic reserve function were determined by Child-Pugh score and albumin-bilirubin (ALBI) score. Forty patients underwent curative radiotherapy, and nine patients with portal vein tumor thrombus (PVTT) underwent palliative radiotherapy as part of multidisciplinary therapy. Local disease control for curative therapy was 80.0% and stereotactic body radiotherapy was 86.7% which was greater than that of conventional radiotherapy (60.0%). Patients with PVTT had a median observation period of 651 days and 75% three-year survival when treated with multitherapy, including radiotherapy for palliative intent, transcatheter arterial chemoembolization, and administration of molecular targeted agents. No adverse events higher than grade 3 and no changes in the Child-Pugh score and ALBI score were seen. Radiotherapy is safe and effective for HCC treatment and can be a part of multidisciplinary therapy.

6.
J Appl Clin Med Phys ; 21(12): 155-165, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33119953

RESUMEN

In conventional stereotactic radiosurgery (SRS), treatment of multiple brain metastases using multiple isocenters is time-consuming resulting in long dose delivery times for patients. A single-isocenter technique has been developed which enables the simultaneous irradiation of multiple targets at one isocenter. This technique requires accurate positioning of the patient to ensure optimal dose coverage. We evaluated the effect of six degrees of freedom (6DoF) setup errors in patient setups on SRS dose distributions for multiple brain metastases using a single-isocenter technique. We used simulated spherical gross tumor volumes (GTVs) with diameters ranging from 1.0 to 3.0 cm. The distance from the isocenter to the target's center was varied from 0 to 15 cm. We created dose distributions so that each target was entirely covered by 100% of the prescribed dose. The target's position vectors were rotated from 0°-2.0° and translated from 0-1.0 mm with respect to the three axes in space. The reduction in dose coverage for the targets for each setup error was calculated and compared with zero setup error. The calculated margins for the GTV necessary to satisfy the tolerance values for loss of GTV coverage of 3% to 10% were defined as coverage-based margins. In addition, the maximum isocenter to target distance for different 6DoF setup errors was calculated to satisfy the tolerance values. The dose coverage reduction and coverage-based margins increased as the target diameter decreased, and the distance and 6DoF setup error increased. An increase in setup error when a single-isocenter technique is used may increase the risk of missing the tumor; this risk increases with increasing distance from the isocenter and decreasing tumor size.


Asunto(s)
Neoplasias Encefálicas , Radiocirugia , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirugía , Humanos , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador
7.
Phys Med ; 73: 73-82, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32330814

RESUMEN

PURPOSE: To investigate the dosimetric impact between the anisotropic analytical algorithm (AAA) and the Acuros XB (AXB) algorithm in volumetric-modulated arc therapy (VMAT) plans for high-grade glioma (HGG). METHODS: We used a heterogeneous phantom to quantify the agreement between the measured and calculated doses from the AAA and from the AXB. We then analyzed 14 patients with HGG treated by VMAT, using the AAA. We newly created AXB plans for each corresponding AAA plan under the following conditions: (1) re-calculation for the same number of monitor units with an identical beam and leaf setup, and (2) re-optimization under the same conditions of dose constraints. The dose coverage for the planning target volume (PTV) was evaluated by dividing the coverage into the skull, air, and soft-tissue regions. RESULTS: Compared to the results obtained with the AAA, the AXB results were in good agreement with the measured profiles. The dose differences in the PTV between the AAA and re-calculated AXB plans were large in the skull region contained in the target. The dose difference in the PTV in both types of plan was significantly correlated with the volume of the skull contained in the target (r = 0.71, p = 0.0042). A re-optimized AXB plan's dose difference was lower vs. the re-calculated AXB plan's. CONCLUSIONS: We observed dose differences between the AAA and AXB plans, in particular in the cases in which the skull region of the target was large. Considering the phantom measurement results, the AXB algorithm should be used in VMAT plans for HGG.


Asunto(s)
Algoritmos , Glioma/patología , Glioma/radioterapia , Radiometría , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia de Intensidad Modulada , Anisotropía , Humanos , Clasificación del Tumor , Fantasmas de Imagen
8.
BMC Cancer ; 20(1): 66, 2020 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-31996182

RESUMEN

BACKGROUND: We sought to construct the optimal neurocognitive function (NCF) change criteria sensitive to health-related quality of life (HR-QOL) in patients who have undergone whole-brain radiation therapy (WBRT) for brain metastasis. METHODS: We categorized the patients by the changes of NCF into groups of improvement versus deterioration if at least one domain showed changes that exceeded the cut-off while other domains remained stable. The remaining patients were categorized as stable, and the patients who showed both significant improvement and deterioration were categorized as 'both.' We examined the clinical meaning of NCF changes using the cut-off values 1.0, 1.5, and 2.0 SD based on the percentage of patients whose HR-QOL changes were ≥ 10 points. RESULTS: Baseline, 4-month and 8-month data were available in 78, 41 (compliance; 85%), and 29 (81%) patients, respectively. At 4 months, improvement/stable/deterioration/both was seen in 15%/12%/41%/32% of the patients when 1.0 SD was used; 19%/22%/37%/22% with 1.5 SD, and 17%/37%/37%/9% with 2.0 SD. The HR-QOL scores on the QLQ-C30 functional scale were significantly worse in the deterioration group versus the others with 1.0 SD (p = 0.013) and 1.5 SD (p = 0.015). With 1.5 SD, the HR-QOL scores on the QLQ-BN20 was significantly better in the improvement group versus the others (p = 0.033). However, when 'both' was included in 'improvement' or 'deterioration,' no significant difference in HR-QOL was detected. CONCLUSIONS: The NCF cut-off of 1.5 SD and the exclusion of 'both' patients from the 'deterioration' and 'improvement' groups best reflects HR-QOL changes.


Asunto(s)
Neoplasias Encefálicas/psicología , Neoplasias Encefálicas/secundario , Cognición , Anciano , Anciano de 80 o más Años , Neoplasias Encefálicas/epidemiología , Neoplasias Encefálicas/radioterapia , Cognición/efectos de la radiación , Irradiación Craneana/efectos adversos , Irradiación Craneana/métodos , Femenino , Encuestas de Atención de la Salud , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Calidad de Vida , Encuestas y Cuestionarios
9.
Clin Transl Radiat Oncol ; 20: 13-18, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31737796

RESUMEN

BACKGROUND AND PURPOSE: Concurrent chemoradiotherapy (CCRT) for head and neck cancer (HNC) is a risk factor for oral candidiasis (OC). As Candida spp. are highly virulent, we conducted a retrospective study to determine whether OC increases the severity of dysphagia related to mucositis in HNC patients. PATIENTS AND METHODS: We retrospectively analyzed the cases of consecutive patients with carcinomas of the oral cavity, pharynx, and larynx who underwent CCRT containing cisplatin (CDDP) at our hospital. The diagnosis of OC was based on gross mucosal appearance. We performed a multivariate analysis to determine whether OC was associated with the development of grade 3 dysphagia in the Radiation Therapy Oncology Group (RTOG) Acute Toxicity Criteria. The maximum of the daily opioid doses was compared between the patients with and without OC. RESULTS: We identified 138 HNC patients. OC was observed in 51 patients (37%). By the time of their OC diagnosis, 19 (37%) had already developed grade 3 dysphagia. Among the 30 patients receiving antifungal therapy, 12 (40%) showed clinical deterioration. In the multivariate analysis, OC was independently associated with grade 3 dysphagia (OR 2.75; 95%CI 1.22-6.23; p = 0.015). The patients with OC required significantly higher morphine-equivalent doses of opioids (45 vs. 30 mg/day; p = 0.029). CONCLUSION: Candida infection causes refractory dysphagia. It is worth investigating whether antifungal prophylaxis reduces severe dysphagia related to candidiasis.

10.
Acta Neuropathol Commun ; 7(1): 119, 2019 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-31345255

RESUMEN

Epithelioid glioblastoma is a rare aggressive variant of glioblastoma (GBM) characterized by a dismal prognosis of about 6 months and frequent leptomeningeal dissemination. A recent study has revealed that 50% of epithelioid GBMs harbor three genetic alterations - BRAF V600E mutation, TERT promoter mutations, and homozygous deletions of CDKN2A/2B. Emerging evidence support the effectiveness of targeted therapies for brain tumors with BRAF V600E mutation. Here we describe a dramatic radiographical response to combined therapy with BRAF and MEK inhibitors in a patient with epithelioid GBM harboring BRAF V600E mutation, characterized by thick spinal dissemination. From relapsed tumor procured at autopsy, we established a cell line retaining the BRAF V600E mutation, TERT promoter mutation and CDKN2A/2B loss. Intracranial implantation of these cells into mice resulted in tumors closely resembling the original, characterized by epithelioid tumor cells and dissemination, and invasion into the perivascular spaces. We then confirmed the efficacy of treatment with BRAF and MEK inhibitor both in vitro and in vivo. Epithelioid GBM with BRAF V600E mutation can be considered a good treatment indication for precision medicine, and this patient-derived cell line should be useful for prediction of the tumor response and clarification of its biological characteristics.


Asunto(s)
Antineoplásicos/administración & dosificación , Neoplasias Encefálicas/tratamiento farmacológico , Glioblastoma/tratamiento farmacológico , Quinasas Quinasa Quinasa PAM/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/administración & dosificación , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Ensayos Antitumor por Modelo de Xenoinjerto/métodos , Animales , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/genética , Línea Celular Tumoral , Quimioterapia Combinada , Predicción , Glioblastoma/diagnóstico por imagen , Glioblastoma/genética , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Persona de Mediana Edad , Mutación/genética , Resultado del Tratamiento
11.
Clin Transl Radiat Oncol ; 18: 39-45, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31341974

RESUMEN

BACKGROUND: Patients with gastrointestinal cancers and brain metastases (BM) represent a unique and heterogeneous population. Our group previously published the Diagnosis-Specific Graded Prognostic Assessment (DS-GPA) for patients with GI cancers (GI-GPA) (1985-2007, n = 209). The purpose of this study is to update the GI-GPA based on a larger contemporary database. METHODS: An IRB-approved consortium database analysis was performed using a multi-institutional (18), multi-national (3) cohort of 792 patients with gastrointestinal (GI) cancers, with newly-diagnosed BM diagnosed between 1/1/2006 and 12/31/2017. Survival was measured from date of first treatment for BM. Multiple Cox regression was used to select and weight prognostic factors in proportion to their hazard ratios. These factors were incorporated into the updated GI-GPA. RESULTS: Median survival (MS) varied widely by primary site and other prognostic factors. Four significant factors (KPS, age, extracranial metastases and number of BM) were used to formulate the updated GI-GPA. Overall MS for this cohort remains poor; 8 months. MS by GPA was 3, 7, 11 and 17 months for GPA 0-1, 1.5-2, 2.5-3.0 and 3.5-4.0, respectively. >30% present in the worst prognostic group (GI-GPA of ≤1.0). CONCLUSIONS: Brain metastases are not uncommon in GI cancer patients and MS varies widely among them. This updated GI-GPA index improves our ability to estimate survival for these patients and will be useful for therapy selection, end-of-life decision-making and stratification for future clinical trials. A user-friendly, free, on-line app to calculate the GPA score and estimate survival for an individual patient is available at brainmetgpa.com.

12.
Transl Res ; 208: 63-72, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30885538

RESUMEN

The literature describing the prognosis of patients with gastrointestinal (GI) cancers and brain metastases (BM) is sparse. Our group previously published a prognostic index, the Graded Prognostic Assessment (GPA) for GI cancer patients with BM, based on 209 patients diagnosed from 1985-2005. The purpose of this analysis is to identify prognostic factors for GI cancer patients with newly diagnosed BM in a larger contemporary cohort. A multi-institutional retrospective IRB-approved database of 792 GI cancer patients with new BM diagnosed from 1/1/2006 to 12/31/2016 was created. Demographic data, clinical parameters, and treatment were correlated with survival and time from primary diagnosis to BM (TPDBM). Kaplan-Meier median survival (MS) estimates were calculated and compared with log-rank tests. The MS from time of first treatment for BM for the prior and current cohorts were 5 and 8 months, respectively (P < 0.001). Eight prognostic factors (age, stage, primary site, resection of primary tumor, Karnofsky Performance Status (KPS), extracranial metastases, number of BM and Hgb were found to be significant for survival, in contrast to only one (KPS) in the prior cohort. In this cohort, the most common primary sites were rectum (24%) and esophagus (23%). Median TPDBM was 22 months. Notably, 37% (267/716) presented with poor prognosis (GPA 0-1.0). Although little improvement in overall survival in this cohort has been achieved in recent decades, survival varies widely and multiple new prognostic factors were identified. Future work will translate these factors into a prognostic index to facilitate clinical decision-making and stratification of future clinical trials.


Asunto(s)
Neoplasias Encefálicas/secundario , Neoplasias Gastrointestinales/patología , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Encefálicas/patología , Estudios de Cohortes , Femenino , Neoplasias Gastrointestinales/secundario , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Pronóstico
14.
J Radiat Res ; 60(2): 249-256, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30649406

RESUMEN

There are no quantitative selection criteria for identifying high-grade glioma (HGG) patients who are suited for volumetric-modulated arc therapy (VMAT). This study aimed to develop selection criteria that can be used for the selection of the optimal treatment modality in HGG. We analyzed 20 patients with HGG treated by 3D conformal radiotherapy (3DCRT). First, VMAT plans were created for each patient retrospectively. For each plan, the normal tissue complication probability (NTCP) for normal brain was calculated. We then divided the patients based on the NTCPs of the 3DCRT plans for normal brain, using the threshold of 5%. We compared the NTCPs of the two plans and the gross tumor volumes (GTVs) of the two groups. For the GTVs, we used receiver operating characteristic curves to identify the cut-off value for predicting NTCP < 5%. We determined the respective correlations between the GTV and the GTV's largest cross-sectional diameter and largest cross-sectional area. In the NTCP ≥ 5% group, the NTCPs for the VMAT plans were significantly lower than those for the 3DCRT plans (P = 0.0011). The NTCP ≥ 5% group's GTV was significantly larger than that of the NTCP < 5% group (P = 0.0016), and the cut-off value of the GTV was 130.5 cm3. The GTV was strongly correlated with the GTV's largest cross-sectional diameter (R2 = 0.82) and largest cross-sectional area (R2 = 0.94), which produced the cut-off values of 7.5 cm and 41 cm2, respectively. It was concluded that VMAT is more appropriate than 3DCRT in cases in which the GTV is ≥130.5 cm3.


Asunto(s)
Glioma/patología , Glioma/radioterapia , Radioterapia Conformacional , Radioterapia de Intensidad Modulada , Adulto , Anciano , Encéfalo , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Probabilidad , Radiometría , Planificación de la Radioterapia Asistida por Computador , Carga Tumoral
15.
Int J Clin Oncol ; 23(6): 1015-1022, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29971621

RESUMEN

BACKGROUND: To determine the current practice of stereotactic irradiation (STI) for brain metastases in Japan by a questionnaire survey. METHODS: A questionnaire was distributed to 313 institutions performing STI with one of the following machines: Gamma Knife (GK), CyberKnife (CK), Novalis (Nov), or other linear accelerator (LINAC)-based systems (OLS). The participation was voluntary. RESULTS: There were 163 responding institutions. The total number of STI treatments between April 2013 and March 2014 was 10,684. Stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (SRT) were performed in 8624 (80.7%) and 2060 (19.3%) cases, respectively. Whole-brain radiation therapy (WBRT) was performed for a total of 3515 cases. For a case model of a 1.5-cm solitary brain metastasis in a non-eloquent area, the most common GTV-PTV margin was 2 mm (22 of 114 institutions), and an institutional standard fraction was 1 (75 of 114 institutions). The doses for the model case also varied from 13.0 to 26.0 Gy (Median 20 Gy) when converted to SRS (α/ß = 10). A prescription point was at the PTV margin the most. The median dose constraints which were converted to SRS (α/ß = 3) to organs at risk were 12.2, 12.7, and 13.7 Gy for optic nerves, cavernous sinus, and brainstem, respectively. CONCLUSIONS: STI for brain metastases in current practice varied significantly among institutions. These different strategies relied mostly on the type of treatment machine used. It is thus necessary to establish a common guideline to express dose prescriptions and plan qualities for different STI machines.


Asunto(s)
Neoplasias Encefálicas/cirugía , Pautas de la Práctica en Medicina/tendencias , Oncología por Radiación/normas , Radiocirugia/métodos , Neoplasias Encefálicas/secundario , Humanos , Japón , Encuestas y Cuestionarios
16.
Clin Transl Radiat Oncol ; 9: 12-17, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29594245

RESUMEN

BACKGROUND AND PURPOSE: To compare chemoradiotherapy (CRT) with low-dose continuous 5-fluorouracil (5FU) to CRT with 5FU+cisplatin (CDDP) for esophageal squamous cell carcinoma (ESCC) in a retrospective cohort study. METHODS AND MATERIALS: We reviewed the cases of Stage I-IV ESCC patients who underwent definitive CRT in 2000-2014. Concomitant chemotherapy was one of the three regimens: (1) high-dose intermittent 5FU and CDDP (standard-dose FP: SDFP), (2) low-dose continuous 5FU and CDDP (LDFP), or (3) low-dose continuous 5FU (LD5FU). The general selection criteria for chemotherapy were: SDFP for patients aged <70 yrs; LDFP for those aged 70-74 yrs; LD5FU for those aged ≥75 yrs or with performance status (PS) ≥3. Propensity scores were derived with chemotherapy (LD5FU vs. 5FU+CDDP) as the dependent variable. RESULTS: In a multivariate analysis, chemotherapy (LD5FU vs. SDFP, p = .24; LDFP vs. SDFP, p = .52) did not affect the overall survival (OS). LD5FU caused significantly less grade 3-4 leukopenia (9%) compared to SDFP (47%) and LDFP (44%) (p < .001). In a propensity-matched analysis, LD5FU affected neither OS (HR 1.06; 95%CI 0.55-2.05; p = .87) nor progression-free survival (HR 0.95, 95%CI 0.50-1.81; p = .87). CONCLUSION: CRT with low-dose continuous 5FU may be a less toxic option for elderly ESCC patients.

17.
Jpn J Radiol ; 35(3): 95-100, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28160228

RESUMEN

PURPOSE: To investigate the effects of a respiratory gating and multifield technique on the dose-volume histogram (DVH) in radiotherapy for esophageal cancer. METHODS AND MATERIALS: Twenty patients who underwent four-dimensional computed tomography for esophageal cancer were included. We retrospectively created the four treatment plans for each patient, with or without the respiratory gating and multifield technique: No gating-2-field, No gating-4-field, Gating-2-field, and Gating-4-field plans. We compared the DVH parameters of the lung and heart in the No gating-2-field plan with the other three plans. RESULT: In the comparison of the parameters in the No gating-2-field plan, there are significant differences in the Lung V5Gy, V20Gy, mean dose with all three plans and the Heart V25Gy-V40Gy with Gating-2-field plan, V35Gy, V40Gy, mean dose with No Gating-4-field plan and V30Gy-V40Gy, and mean dose with Gating-4-field plan. The lung parameters were smaller in the Gating-2-field plan and larger in the No gating-4-field and Gating-4-field plans. The heart parameters were all larger in the No gating-2-field plan. CONCLUSION: The lung parameters were reduced by the respiratory gating technique and increased by the multifield technique. The heart parameters were reduced by both techniques. It is important to select the optimal technique according to the risk of complications.


Asunto(s)
Neoplasias Esofágicas/diagnóstico por imagen , Neoplasias Esofágicas/radioterapia , Técnicas de Imagen Sincronizada Respiratorias/métodos , Anciano , Anciano de 80 o más Años , Neoplasias Esofágicas/fisiopatología , Femenino , Tomografía Computarizada Cuatridimensional/métodos , Corazón/fisiopatología , Corazón/efectos de la radiación , Humanos , Pulmón/fisiopatología , Pulmón/efectos de la radiación , Masculino , Persona de Mediana Edad , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia Guiada por Imagen/métodos
18.
Int J Mol Sci ; 17(11)2016 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-27827891

RESUMEN

Our objectives were to (1) investigate the feasibility of the use of the Japanese version of the Hopkins Verbal Learning Test-Revised (HVLT-R); (2) identify the clinical factors influencing the HVLT-R scores of patients undergoing whole-brain radiation therapy (WBRT); and (3) compare the neurocognitive function (NCF) after WBRT in different dose fractionation schedules. We administered the HVLT-R (Japanese version) before (baseline) and at four and eight months after WBRT in 45 patients who received either therapeutic (35Gy-in-14, n = 16; 30Gy-in-10, n = 18) or prophylactic (25Gy-in-10, n = 11) WBRT. Sixteen patients dropped out before the eight-month examination, due mostly to death from cancer. The Karnofsky Performance Status (KPS) 80-100 group had significantly higher baseline total recall (TR) scores (p = 0.0053), delayed recall (DR) scores (p = 0.012), and delayed recognition (DRecog) scores (p = 0.0078). The patients aged ≤65 years also had significantly higher TR scores (p = 0.030) and DRecog scores (p = 0.031). The patients who underwent two examinations (worse-prognosis group) had significantly decreased DR scores four months after WBRT compared to the baseline (p = 0.0073), and they were significantly more likely to have declined individual TR scores (p = 0.0017) and DR scores (p = 0.035) at four months. The eight-month HVLT-R scores did not significantly decline regardless of the WBRT dose fractionation. The baseline NCF was determined by age and KPS, and the early decline in NCF is characteristic of the worse-prognosis group.


Asunto(s)
Neoplasias Encefálicas/psicología , Neoplasias Encefálicas/radioterapia , Cognición/efectos de la radiación , Memoria/efectos de la radiación , Aprendizaje Verbal/efectos de la radiación , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/fisiopatología , Estudios Controlados Antes y Después , Irradiación Craneana , Fraccionamiento de la Dosis de Radiación , Femenino , Humanos , Estado de Ejecución de Karnofsky , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Pronóstico , Análisis de Supervivencia
19.
BMJ Case Rep ; 20152015 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-26135495

RESUMEN

Although oesophageal candidiasis is usually a superficial mucosal infection, necrotising Candida oesophagitis has been reported to cause oesophageal perforation or lung abscess. We report the case of an elderly Japanese man presenting with painless dysphagia after thoracic radiotherapy for oesophageal cancer. Non-contrast CT demonstrated segmental and oedematous thickening of the oesophageal wall. Endoscopy revealed white plaques on the oesophageal mucosa. The patient's oesophagitis responded to systemic antifungal therapy, and did not lead to oesophageal perforation. He died of recurrent oesophageal cancer several months later. The importance of severe radiation-induced oesophagitis without pain, our pathophysiological hypothesis on the local oedema caused by Candida infection and the usefulness of CT in evaluating abnormal thickening of the gastrointestinal tract are discussed separately in the article.


Asunto(s)
Candidiasis/complicaciones , Trastornos de Deglución/patología , Neoplasias Esofágicas/patología , Esofagitis/etiología , Anciano , Candida/aislamiento & purificación , Trastornos de Deglución/diagnóstico por imagen , Trastornos de Deglución/etiología , Neoplasias Esofágicas/complicaciones , Neoplasias Esofágicas/diagnóstico por imagen , Esofagectomía , Resultado Fatal , Humanos , Masculino , Recurrencia Local de Neoplasia , Radiografía
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