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1.
Jpn J Radiol ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38625476

RESUMO

PURPOSE: Stereotactic body radiotherapy (SBRT) boost is a promising treatment for cervical cancer patients who are ineligible for intracavitary brachytherapy (ICBT). The aim of this multicenter, single-arm, phase I/II study was to prospectively evaluate the efficacy and toxicity of SBRT boost. MATERIALS AND METHODS: ICBT-ineligible patients with untreated cervical cancer were enrolled. Patients underwent whole-pelvic radiotherapy (45 Gy in 25 fractions) with SBRT boost to the primary lesion. In the phase I dose-escalation cohort (3 + 3 design), patients were treated with SBRT boost of 21 or 22.5 Gy in three fractions. Although dose-limiting toxicity was not confirmed, a dose of 21 Gy was selected for the phase II cohort because it was difficult to reproduce the pelvic organs position in two patients during the phase I trial. The primary endpoint was 2-year progression-free survival. RESULTS: Twenty-one patients (phase I, n = 3; phase II, n = 18) were enrolled between April 2016 and October 2020; 17 (81%) had clinical stage III-IV (with para-aortic lymph node metastases) disease. The median (range) follow-up was 40 (10-84) months. The initial response was complete response in 20 patients and partial response in one patient. The 2-year locoregional control, progression-free survival, and overall survival rates were 84%, 67%, and 81%, respectively. Grade ≥ 3 toxicity was confirmed in one patient each in the acute (diarrhea) and late (urinary tract obstruction) phases. CONCLUSION: These findings suggested that a SBRT boost is more effective than the conventional EBRT boost and can be an important treatment option for ICBT-ineligible patients with cervical cancer. STUDY REGISTRATION: This study was registered at the University Hospital Medical Information Network Clinical Trials Registry (UMIN000036845).

3.
EJNMMI Radiopharm Chem ; 9(1): 17, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38407647

RESUMO

BACKGROUND: L-type amino acid transporter 1 (LAT1) is overexpressed in various cancers; therefore, radiohalogen-labeled amino acid derivatives targeting LAT1 have emerged as promising candidates for cancer radiotheranostics. However, 211At-labeled amino acid derivatives exhibit instability against deastatination in vivo, making it challenging to use 211At for radiotherapy. In this study, radiohalogen-labeled amino acid derivatives with high dehalogenation stability were developed. RESULTS: We designed and synthesized new radiohalogen-labeled amino acid derivatives ([211At]At-NpGT, [125I]I-NpGT, and [18F]F-NpGT) in which L-tyrosine was introduced into the neopentyl glycol (NpG) structure. The radiolabeled amino acid derivatives were recognized as substrates of LAT1 in the in vitro studies using C6 glioma cells. In a biodistribution study using C6 glioma-bearing mice, these agents exhibited high stability against in vivo dehalogenation and similar biodistributions. The similarity of [211At]At-NpGT and [18F]F-NpGT indicated that these pairs of radiolabeled compounds would be helpful in radiotheranostics. Moreover, [211At]At-NpGT exhibited a dose-dependent inhibitory effect on the growth of C6 glioma-bearing mice. CONCLUSIONS: [211At]At-NpGT exhibited a dose-dependent inhibitory effect on the tumor growth of glioma-bearing mice, and its biodistribution was similar to that of other radiohalogen-labeled amino acid derivatives. These findings suggest that radiotheranostics using [18F]F-NpGT and [123/131I]I-NpGT for diagnostic applications and [211At]At-NpGT and [131I]I-NpGT for therapeutic applications are promising.

4.
Radiol Phys Technol ; 17(1): 269-279, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38336939

RESUMO

To improve image quality for low-count bone scintigraphy using deep learning and evaluate their clinical applicability. Six hundred patients (training, 500; validation, 50; evaluation, 50) were included in this study. Low-count original images (75%, 50%, 25%, 10%, and 5% counts) were generated from reference images (100% counts) using Poisson resampling. Output (DL-filtered) images were obtained after training with U-Net using reference images as teacher data. Gaussian-filtered images were generated for comparison. Peak signal-to-noise ratio (PSNR) and structural similarity (SSIM) to the reference image were calculated to determine image quality. Artificial neural network (ANN) value, bone scan index (BSI), and number of hotspots (Hs) were computed using BONENAVI analysis to assess diagnostic performance. Accuracy of bone metastasis detection and area under the curve (AUC) were calculated. PSNR and SSIM for DL-filtered images were highest in all count percentages. BONENAVI analysis values for DL-filtered images did not differ significantly, regardless of the presence or absence of bone metastases. BONENAVI analysis values for original and Gaussian-filtered images differed significantly at ≦25% counts in patients without bone metastases. In patients with bone metastases, BSI and Hs for original and Gaussian-filtered images differed significantly at ≦10% counts, whereas ANN values did not. The accuracy of bone metastasis detection was highest for DL-filtered images in all count percentages; the AUC did not differ significantly. The deep learning method improved image quality and bone metastasis detection accuracy for low-count bone scintigraphy, suggesting its clinical applicability.


Assuntos
Neoplasias Ósseas , Aprendizado Profundo , Humanos , Melhoria de Qualidade , Processamento de Imagem Assistida por Computador/métodos , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/secundário , Cintilografia
5.
Radiol Case Rep ; 19(5): 1718-1721, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38384707

RESUMO

We report the case of a woman in her 40s who presented with sensory disturbances in all 4 limbs and left facial palsy. MRI revealed asymmetric enlargement of the dorsal root ganglia, which was enhanced by gadolinium-a chest CT scan identified enlarged supraclavicular, mediastinal, and hilar lymph nodes. A biopsy of a hilar lymph node showed noncaseating epithelioid granulomas, confirming a sarcoidosis diagnosis. Prednisolone treatment led to symptomatic improvements. In sarcoidosis of the peripheral nervous system, there might be observable enlargement of the dorsal root ganglion alongside enhanced gadolinium contrast. Obtaining a biopsy from the dorsal root ganglion poses challenges, and radiologists should be mindful of this specific imaging characteristic.

6.
Anticancer Res ; 43(12): 5705-5712, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38030183

RESUMO

BACKGROUND/AIM: The purpose of this study was to examine the prognostic value of Prostate imaging-reporting and data system (PI-RADS) v2.1 scoring system in patients who underwent radical prostatectomy (RP). PATIENTS AND METHODS: Clinical data of 294 patients who received RP between 2006 and 2018 were reviewed and multiple parameters including PI-RADS v2.1 score were employed to identify predictive factors for biochemical recurrence (BCR). Tumor volume was calculated from prostatectomy specimens. RESULTS: Median age at operation and initial PSA level were 67 years old and 7.68 ng/ml, respectively. 44.9 and 24.8% of patients were diagnosed with PI-RADS score 4 and 5 prior to biopsies, respectively. BCR was observed in 17% of patients and median observation period was 63.43 months. After multivariate analysis, PI-RADS v2.1 score 5 [hazard ratio (HR)=2.24, p=0.0124] was an independent predictive factor of BCR in addition to clinical T stage (≥2c) (HR=2.32, p=0.0093) and biopsy Gleason score (≥8) (HR=2.81, p=0.0007). Furthermore, PI-RADS score 5 significantly stratified the prognosis in D'Amico intermediate- and high-risk groups (p=0.0174 and p=0.0013, respectively). We established novel risk classifications including PI-RADS v2.1 score and found that prognostic capabilities were improved as compared to the D'Amico classification. CONCLUSION: The PI-RADS v2.1 score exhibited significant prognostic value in patients with localized prostate cancer following RP. Risk classifications based on PI-RADS v2.1 score might provide better ability for predicting oncological outcomes as compared to the D'Amico classification system.


Assuntos
Próstata , Neoplasias da Próstata , Masculino , Humanos , Idoso , Próstata/diagnóstico por imagem , Próstata/cirurgia , Próstata/patologia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/patologia , Imageamento por Ressonância Magnética , Estudos Retrospectivos , Prostatectomia
7.
Cancer Med ; 12(22): 21032-21040, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37902228

RESUMO

BACKGROUND: This study analyzed the impact of the coronavirus disease 2019 (COVID-19) pandemic on radiotherapy delivery in Japan using a high-quality Japanese national database based on universal health coverage. METHODS: We performed a retrospective observational study using National Database of Health Insurance Claims and Specific Health Checkups of Japan open data focused on radiotherapy between fiscal year (FY) 2019 and FY2020 and the number of COVID-19 cases from the Ministry of Health, Labour, and Welfare. We statistically analyzed the relationship between the number of COVID-19 cases and the number of radiotherapy deliveries in Japan as a whole and by prefecture. RESULTS: The total number of external beam radiotherapy (EBRT) fractions was 4,472,140 in FY2019 and 4,227,673 in FY2020 (-5.8%). EBRT courses were 250,395 in FY2019 and 240,329 in FY2020 (-4.0%), stereotactic radiotherapy courses were 27,619 in FY2019 and 31,786 in FY2020 (+15.1%), and single-fraction palliative radiotherapy courses were 4124 in FY2019 and 5255 in FY2020 (+21.5%). The total number of breast and prostate hypofractionated radiotherapy (HFRT) fractions was 155,773 and 48,188 in FY2019, and 200,256 and 84,230 in FY2020 (+28.6% and +74.8%), respectively. In the Pearson correlation analysis, EBRT fractions were lower, and breast HFRT fractions were higher in prefectures with more COVID-19 cases. CONCLUSIONS: Overall, radiotherapy delivery in Japan was relatively stable after the pandemic, with an increase in HFRT. Also, EBRT fractions decreased, and breast HFRT were more likely to be used in prefectures with more COVID-19 cases.


Assuntos
COVID-19 , Pandemias , Masculino , Humanos , Japão/epidemiologia , COVID-19/epidemiologia , Hipofracionamento da Dose de Radiação , Antígeno Prostático Específico
8.
Oncol Lett ; 26(5): 499, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37854867

RESUMO

The present study employed artificial intelligence (AI) machine learning technology to evaluate the prognosis of gastric cancer using blood collection data, commonly used in clinical practice and subsequently performed a stratification distinct from conventional tumor-node-metastasis (TNM) classification. Experiments were conducted using four machine learning methods, namely, logistic regression (LR), random forest (RF), gradient boosting (GB) and deep neural network (DNN), to classify good or poor post-5-year prognosis based on clinicopathological data and post-5-year relapse occurrence. For each machine learning method, the importance was sorted in descending order (from the most to the least); the top features were used for clustering using the k-medoids method. The prediction accuracy and area under the curve (AUC) for 5-year survival were as follows: LR, 76.8% and 0.702; RF, 72.5% and 0.721; GB, 75.3% and 0.73; DNN, 76.9% and 0.682, respectively. The prediction accuracy and AUC for 5-year recurrence-free survival were as follows: LR, 85.5% and 0.692; RF, 79.0% and 0.721; GB, 80.5% and 0.718; DNN, 83.2% and 0.670. Clustering patients into three groups resulted in a stratification distinct from the TNM classification. In conclusion, AI machine learning using routine clinical data can help evaluate the prognosis of gastric cancer, with prognosis differing according to AI-identified clusters.

9.
Cancers (Basel) ; 15(17)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37686657

RESUMO

Surgery is the standard treatment for stage I non-small cell lung cancer (NSCLC); however, no clear randomized trial demonstrates its superiority to stereotactic body radiotherapy (SBRT) regarding survival. We aimed to retrospectively evaluate the treatment outcomes of SBRT in operable patients with stage I NSCLC using a large Japanese multi-institutional database to show real-world outcome. Exactly 399 patients (median age 75 years; 262 males and 137 females) with stage I (IA 292, IB 107) histologically proven NSCLC (adenocarcinoma 267, squamous cell carcinoma 96, others 36) treated at 20 institutions were reviewed. SBRT was prescribed at a total dose of 48-70 Gy in 4-10 fractions. The median follow-up period was 38 months. Local progression-free survival rates were 84.2% in all patients and 86.1% in the T1, 78.6% in T2, 89.2% in adenocarcinoma, and 70.5% in squamous cell subgroups. Overall 3-year survival rates were 77.0% in all patients: 90.7% in females, 69.6% in males, and 41.2% in patients with pulmonary interstitial changes. Fatal radiation pneumonitis was observed in two patients, all of whom had pulmonary interstitial changes. This real-world evidence will be useful in shared decision-making for optimal treatment, including SBRT for operable stage I NSCLC, particularly in older patients.

10.
Heart Vessels ; 38(11): 1318-1328, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37552271

RESUMO

Fractional flow reserve derived from coronary CT (FFR-CT) is a noninvasive physiological technique that has shown a good correlation with invasive FFR. However, the use of FFR-CT is restricted by strict application standards, and the diagnostic accuracy of FFR-CT analysis may potentially be decreased by severely calcified coronary arteries because of blooming and beam hardening artifacts. The aim of this study was to evaluate the utility of deep learning (DL)-based coronary computed tomography (CT) data analysis in predicting invasive fractional flow reserve (FFR), especially in cases with severely calcified coronary arteries. We analyzed 184 consecutive cases (241 coronary arteries) which underwent coronary CT and invasive coronary angiography, including invasive FFR, within a three-month period. Mean coronary artery calcium scores were 963 ± 1226. We evaluated and compared the vessel-based diagnostic accuracy of our proposed DL model and a visual assessment to evaluate functionally significant coronary artery stenosis (invasive FFR < 0.80). A deep neural network was trained with consecutive short axial images of coronary arteries on coronary CT. Ninety-one coronary arteries of 89 cases (48%) had FFR-positive functionally significant stenosis. On receiver operating characteristics (ROC) analysis to predict FFR-positive stenosis using the trained DL model, average area under the curve (AUC) of the ROC curve was 0.756, which was superior to the AUC of visual assessment of significant (≥ 70%) coronary artery stenosis on CT (0.574, P = 0.011). The sensitivity, specificity, positive and negative predictive value (PPV and NPV), and accuracy of the DL model and visual assessment for detecting FFR-positive stenosis were 82 and 36%, 68 and 78%, 59 and 48%, 87 and 69%, and 73 and 63%, respectively. Sensitivity and NPV for the prediction of FFR-positive stenosis were significantly higher with our DL model than visual assessment (P = 0.0004, and P = 0.024). DL-based coronary CT data analysis has a higher diagnostic accuracy for functionally significant coronary artery stenosis than visual assessment.


Assuntos
Doença da Artéria Coronariana , Estenose Coronária , Aprendizado Profundo , Reserva Fracionada de Fluxo Miocárdico , Humanos , Constrição Patológica , Reserva Fracionada de Fluxo Miocárdico/fisiologia , Estenose Coronária/diagnóstico por imagem , Angiografia Coronária/métodos , Valor Preditivo dos Testes , Angiografia por Tomografia Computadorizada/métodos , Tomografia Computadorizada Multidetectores/métodos
11.
J Magn Reson Imaging ; 2023 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-37572088

RESUMO

BACKGROUND: Patient-friendly audiovisual (AV) systems in head MRI examinations can potentially reduce patient anxiety and contrast-enhanced MRI (CE-MRI) adverse reactions to gadolinium. PURPOSE: To evaluate whether a patient-friendly AV system reduces the rate of adverse reactions to gadolinium-based contrast agents. STUDY TYPE: Retrospective. POPULATION: Four thousand eight hundred thirty-two outpatients (2462 female) attending for clinical CE-MRI studies. (Gadoteridol: 1971, Meglumine gadoterate: 2733, Gadobutrol: 128.) FIELD STRENGTH/SEQUENCE: Routine CE-MRI of head and neck using a 1.5 T or 3 T scanner with or without a patient-friendly AV system. ASSESSMENT: One thousand one hundred fifty-nine patients were scanned on MRI machines equipped with patient-friendly AV systems (AV group) and 3673 on MRI machines without AV systems (control group). Adverse reaction rate and symptoms were reviewed by referring to the system database and electronic medical records and compared between the two groups. Adverse reactions were defined as physiological reactions, such as vomiting and allergic-like reactions, such as urticaria, occurring within 1 hour of contrast injection. We compare patient backgrounds, adverse reaction rate, adverse reactions symptoms and the severity between the two groups. STATISTICAL TESTS: Adverse reaction rate with and without a patient-friendly AV system were compared using Fisher's exact test. The relationship between patient-friendly AV systems and the occurrence of adverse reactions was evaluated with logistic regression. Statistical significance was set at P < 0.05. RESULTS: Of the 4832 patients enrolled, 65 (1.35%) experienced adverse reactions. The most common adverse reactions in both groups were urticaria and pruritus. Adverse reaction rate was significantly lower in the AV group than in the control group (0.7% vs. 1.6%). No significant difference was observed in the severity (P = 1.000) of adverse reactions and symptoms (allergic-like reaction: P = 0.08, physiologic reaction: P = 1.000) between the two groups. DATA CONCLUSION: The patient-friendly AV system significantly reduce adverse reaction occurrence to gadolinium-based contrast agents. EVIDENCE LEVEL: 4 TECHNICAL EFFICACY: Stage 1.

12.
BMC Med Imaging ; 23(1): 102, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37528392

RESUMO

BACKGROUND: Megavoltage computed tomography (MVCT) images acquired during each radiotherapy session may be useful for delta radiomics. However, no studies have examined whether the MVCT-based radiomics has prognostic power. Therefore, the purpose of this study was to examine the prognostic power of the MVCT-based radiomics for head and neck squamous cell carcinoma (HNSCC) patients. METHODS: 100 HNSCC patients who received definitive radiotherapy were analyzed and divided into two groups: training (n = 70) and test (n = 30) sets. MVCT images obtained using TomoTherapy for the first fraction of radiotherapy and planning kilovoltage CT (kVCT) images obtained using Aquilion LB CT scanner were analyzed. Primary gross tumor volume (GTV) was propagated from kVCT to MVCT images using rigid registration, and 107 radiomic features were extracted from the GTV in MVCT and kVCT images. Least absolute shrinkage and selection operator (LASSO) Cox regression model was used to examine the association between overall survival (OS) and rad score calculated for each patient by weighting the feature value through the coefficient when features were selected. Then, the predictive values of MVCT-based and kVCT-based rad score and patient-, treatment-, and tumor-specific factors were evaluated. RESULTS: C-indices of the rad score for MVCT- and kVCT-based radiomics were 0.667 and 0.685, respectively. The C-indices of 6 clinical factors were 0.538-0.622. The 3-year OS was significantly different between high- and low-risk groups according to the MVCT-based rad score (50% vs. 83%; p < 0.01). CONCLUSIONS: Our results suggested that MVCT-based radiomics had stronger prognostic power than any single clinical factor and was a useful prognostic factor when predicting OS in HNSCC patients.


Assuntos
Neoplasias de Cabeça e Pescoço , Tomografia Computadorizada por Raios X , Humanos , Tomografia Computadorizada por Raios X/métodos , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico por imagem , Planejamento da Radioterapia Assistida por Computador/métodos , Prognóstico , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem
14.
Int J Radiat Oncol Biol Phys ; 117(5): 1118-1124, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37414261

RESUMO

PURPOSE: We previously reported the primary results of JCOG0701, a randomized, multicenter, phase 3, noninferiority trial comparing accelerated fractionation (Ax) to standard fractionation (SF) for early glottic cancer. In the primary results, although the similar efficacy of 3-year progression-free survival and toxicity of Ax compared with SF was observed, the noninferiority of Ax was not confirmed statistically. To evaluate the long-term follow-up results of JCOG0701, we conducted JCOG0701A3 as an ancillary study of JCOG0701. METHODS AND MATERIALS: In JCOG0701, 370 patients were randomly assigned to receive SF of 66 to 70 Gy (33-35 fractions; n = 184) or Ax of 60 to 64.8 Gy (25-27 fractions; n = 186). The data cutoff date for this analysis was in June 2020. Overall survival, progression-free survival, and late adverse events including central nervous system ischemia were analyzed. RESULTS: With a median follow-up period of 7.1 years (range, 0.1-12.4), progression-free survival of the SF and Ax arms were 76.2% and 78.2% at 5 years and 72.7% and 74.8% at 7 years (P = .44). OS of the SF and Ax arms were 92.7% and 89.6% at 5 years and 90.8% and 86.5% at 7 years (P = .92). Among 366 patients with a protocol treatment, the cumulative incidence of late adverse events of the SF and Ax arms were 11.9% and 7.4% at 8 years (hazard ratio, 0.53; 95% CI, 0.28-1.01; P = .06). Central nervous system ischemia of grade 2 or higher was observed in 4.1% for the SF arm and 1.1% for the Ax arm (P = .098). CONCLUSIONS: After long-term follow-up, Ax showed comparable efficacy to SF and a tendency for better safety. Ax may be suitable for early glottic cancer because of its convenience in minimizing treatment time, cost, and labor.


Assuntos
Neoplasias Laríngeas , Humanos , Seguimentos , Intervalo Livre de Doença , Neoplasias Laríngeas/radioterapia , Fracionamento da Dose de Radiação , Isquemia
15.
Acta Radiol ; 64(9): 2627-2635, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37376758

RESUMO

BACKGROUND: Demyelinating peripheral neuropathy is characteristic of both polyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes (POEMS) syndrome and chronic inflammatory demyelinating polyneuropathy (CIDP). We hypothesized that the different pathogeneses underlying these entities would affect the sonographic imaging features. PURPOSE: To investigate whether ultrasound (US)-based radiomic analysis could extract features to describe the differences between CIDP and POEMS syndrome. MATERIAL AND METHODS: In this retrospective study, we evaluated nerve US images from 26 with typical CIDP and 34 patients with POEMS syndrome. Cross-sectional area (CSA) and echogenicity of the median and ulnar nerves were evaluated in each US image of the wrist, forearm, elbow, and mid-arm. Radiomic analysis was performed on these US images. All radiomic features were examined using receiver operating characteristic analysis. Optimal features were selected using a three-step feature selection method and were inputted into XGBoost to build predictive machine-learning models. RESULTS: The CSAs were more enlarged in patients with CIDP than in those with POEMS syndrome without significant differences, except for that of the ulnar nerve at the wrist. Nerve echogenicity was significantly more heterogeneous in patients with CIDP than in those with POEMS syndrome. The radiomic analysis yielded four features with the highest area under the curve (AUC) value of 0.83. The machine-learning model showed an AUC of 0.90. CONCLUSION: US-based radiomic analysis has high AUC values in differentiating POEM syndrome from CIDP. Machine-learning algorithms further improved the discriminative ability.


Assuntos
Síndrome POEMS , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica , Humanos , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/diagnóstico por imagem , Síndrome POEMS/diagnóstico por imagem , Estudos Retrospectivos , Nervos Periféricos , Ultrassonografia
16.
J Appl Clin Med Phys ; 24(7): e14071, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37327042

RESUMO

INTRODUCTION: Dosimetric accuracy is critical when a patient treated with volumetric modulated arc therapy (VMAT) is transferred to another beam-matched linac. To evaluate the performance of Accelerated Go Live (AGL) service, the measured beam characteristics and patient specific quality assurance (QA) results between two AGL-matched linacs were compared. MATERIALS AND METHODS: Two VersaHD linacs were installed using the AGL service. After the installation, the beam data such as percentage depth dose (PDD), lateral profiles and output factors for all photon beams were measured. Relative doses were also measured as a function of the multi-leaf collimator (MLC) leaf gap width. Subsequently, VMAT plans were created for prostate, pelvis, head and neck, liver, lung cancers and multiple brain metastases. Dose distributions and point doses were measured by multi-dimensional detectors and ionization chambers for patient specific quality assurance, and comparisons were made between the two linacs. RESULTS: Dose differences in PDDs were all within ± 1% except the entrance region, and the averaged gamma indices of the lateral profiles were within 0.3. The differences in doses as a function of the MLC leaf gap width between the two linacs were within ±0.5%. For all the plans, gamma passing rates were all higher than 95% with criteria of 2%/2 mm. The average and the SD of dose differences on the multi-dimensional detector between both measurements was 0.06 ± 2.12%, and the average of point dose differences was -0.03 ± 0.33%. CONCLUSION: We have evaluated the AGL performance in the context of beam characteristics and patient specific QA. It was demonstrated that the AGL service provides an accurate VMAT treatment reproducibility for many tumor sites with gamma pass rates greater than 95% under criteria of 2%/2 mm.


Assuntos
Neoplasias Encefálicas , Radioterapia de Intensidade Modulada , Humanos , Aceleradores de Partículas , Radioterapia de Intensidade Modulada/métodos , Reprodutibilidade dos Testes , Planejamento da Radioterapia Assistida por Computador/métodos , Dosagem Radioterapêutica
17.
Jpn J Radiol ; 41(11): 1316-1322, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37354344

RESUMO

PURPOSE: The aim of this study was to develop a new workflow for 1.5-T magnetic resonance (MR)-guided on-line adaptive radiation therapy (MRgART) and assess its feasibility in achieving dose constraints. MATERIALS AND METHODS: We retrospectively evaluated the clinical data of patients who underwent on-line adaptive radiation therapy using a 1.5-T MR linear accelerator (MR-Linac). The workflow in MRgART was established by reviewing the disease site, number of fractions, and re-planning procedures. Five cases of prostate cancer were selected to evaluate the feasibility of the new workflow with respect to achieving dose constraints. RESULTS: Between December 2021 and September 2022, 50 consecutive patients underwent MRgART using a 1.5-T MR-Linac. Of these, 20 had prostate cancer, 10 had hepatocellular carcinoma, 6 had pancreatic cancer, 5 had lymph node oligo-metastasis, 3 had renal cancer, 3 had bone metastasis, 2 had liver metastasis from colon cancer, and 1 had a mediastinal tumor. Among a total of 247 fractions, 235 (95%) were adapt-to-shape (ATS)-based re-planning. The median ATS re-planning time in all 50 cases was 17 min. In the feasibility study, all dose constraint sets were met in all 5 patients by ATS re-planning. Conversely, a total of 14 dose constraints in 5 patients could not be achieved by virtual plan without using adaptive re-planning. These dose constraints included the minimum dose received by the highest irradiated volume of 1 cc in the planning target volume and the maximum dose of the rectal/bladder wall. CONCLUSION: A new workflow of 1.5-T MRgART was established and found to be feasible. Our evaluation of the dose constraint achievement demonstrated the effectiveness of the workflow.


Assuntos
Neoplasias da Próstata , Planejamento da Radioterapia Assistida por Computador , Masculino , Humanos , Planejamento da Radioterapia Assistida por Computador/métodos , Dosagem Radioterapêutica , Fluxo de Trabalho , Estudos Retrospectivos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Espectroscopia de Ressonância Magnética
19.
Interv Radiol (Higashimatsuyama) ; 8(1): 1-6, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36936258

RESUMO

Purpose: Postembolization syndrome (PES) after renal arterial embolization (RAE) can reduce the patient's tolerance of the procedure and extend the length of hospital stay. We aimed to assess the efficacy of steroid administration in preventing PES in patients undergoing RAE for angiomyolipoma (AML). Material and Methods: Between May 2004 and March 2020, 29 RAE procedures in 26 patients with AML were performed. Patient information, including age, sex, tumor size, tuberous sclerosis complex-associated/sporadic AML, hemorrhagic/nonhemorrhagic AML, embolic material, steroid use, medication type, some blood laboratory parameters, hospital stay, and PES occurrence were retrospectively obtained. The prophylactic steroid protocol used in the study was as follows: 250 mg of intravenous methylprednisolone (Solu-Medrol) 2 h before the RAE procedure, followed by 2 days of intravenous prednisolone (Predonine; 2 mg/kg/day), which was tapered by halving the dose every 2 days within the course of 2 weeks. After the discharge, intravenous prednisolone was changed to oral prednisolone (Predonine). PES was defined as the presence of fever, pain, nausea, or vomiting. Data were compared between the steroid and non-steroid groups and between PES and non-PES groups. Results: The PES incidence rate was 76%, and a comparison between the steroid and non-steroid groups revealed that steroid use significantly decreased the incidence of PES (P < 0.001), including fever (P < 0.001), pain (P = 0.005), and nausea (P = 0.028). The use of anti-inflammatory drugs during the hospital stay was significantly lower in the steroid group (P = 0.019). Moreover, in the steroid group, C-reactive protein level was significantly lower (P = 0.006), whereas white blood cell count was significantly higher (P = 0.004). Conversely, the median length of hospital stay was not significantly shorter in the steroid group (P = 0.292). Conclusions: The prophylactic use of steroids before and after embolization of renal AML may be effective in preventing PES in this small retrospective study.

20.
PLoS One ; 18(3): e0282710, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37000854

RESUMO

OBJECTIVES: We investigated prospectively whether, in cervical cancer (CC) treated with concurrent chemoradiotherapy (CCRT), the Apparent diffusion coefficient (ADC) histogram and texture parameters and their change rates during treatment could predict prognosis. METHODS: Fifty-seven CC patients treated with CCRT at our institution were included. They underwent MRI scans up to four times during the treatment course (1st, before treatment [n = 41], 2nd, at the start of image-guided brachytherapy (IGBT) [n = 41], 3rd, in the middle of IGBT [n = 27], 4th, after treatment [n = 53]). The entire tumor was manually set as the volume of interest (VOI) manually in the axial images of the ADC map by two radiologists. A total of 107 image features (morphology features 14, histogram features 18, texture features 75) were extracted from the VOI. The recurrence prediction values of the features and their change rates were evaluated by Receiver operating characteristics (ROC) analysis. The presence or absence of local and distant recurrence within two years was set as an outcome. The intraclass correlation coefficient (ICC) was also calculated. RESULTS: The change rates in kurtosis between the 1st and 3rd, and 1st and 2nd MRIs, and the change rate in grey level co-occurrence matrix_cluster shade between the 2nd and 3rd MRIs showed particularly high predictive powers (area under the ROC curve = 0.785, 0.759, and 0.750, respectively), which exceeded the predictive abilities of the parameters obtained from pre- or post-treatment MRI only. The change rate in kurtosis between the 1st and 2nd MRIs had good reliability (ICC = 0.765). CONCLUSIONS: The change rate in ADC kurtosis between the 1st and 2nd MRIs was the most reliable parameter, enabling us to predict prognosis early in the treatment course.


Assuntos
Neoplasias do Colo do Útero , Feminino , Humanos , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/terapia , Resultado do Tratamento , Reprodutibilidade dos Testes , Prognóstico , Imagem de Difusão por Ressonância Magnética/métodos , Quimiorradioterapia/métodos , Curva ROC , Estudos Retrospectivos
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