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19 result(s) for "Nakasato, Tatsuhiko"
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18FFDG uptake in axillary lymph nodes and deltoid muscle after COVID-19 mRNA vaccination: a cohort study to determine incidence and contributing factors using a multivariate analysis
PurposeReactive FDG uptake in the axillary lymph nodes (ALN) and deltoid muscle (DM) after COVID-19 mRNA vaccination has been recognized, although the actual situation in the Japanese population remains unknown. To determine the incidence of reactive FDG uptake and its contributing factors, we retrospectively studied a cohort of subjects who were vaccinated at our hospital.MethodsWhole-body FDG-PET/CT examinations performed in 237 subjects out of 240 subjects with a definite history of COVID-19 vaccination (BNT162b2; BioNTech-Pfizer) were analyzed. Positivity and SUVmax of FDG uptake in the ALN and DM ipsilateral to vaccination, various subject characteristics, and the grade of the pathological FDG-PET/CT findings were evaluated using a multivariate analysis.ResultsFDG uptake in the ALN and DM ipsilateral to vaccination was seen in about 60% of the subjects even soon (0–4 days) after the first vaccination, with percentages reaching 87.5% and 75.0%, respectively, after the second vaccination. DM uptake had almost disappeared at around 2 weeks, while ALN uptake persisted for 3 weeks or longer. A multivariate analysis showed that a short duration since vaccination, a younger age, a female sex, and a low FDG-PET/CT grade (minimal pathological FDG uptake) contributed significantly to positive ALN uptake, while a short duration since vaccination and a female sex were the only significant contributors to positive DM uptake. This study is the first to identify factors contributing to positive FDG uptake in ALN and DM after COVID-19 vaccination.ConclusionA high incidence of FDG uptake in ALN and DM was observed after vaccination. ALN uptake seemed to be associated with a younger age, a female sex, and minimal pathological FDG uptake. After vaccination, an acute inflammatory reaction in DM followed by immune reaction in ALN linked to humoral immunity may be speculated.
Proton beam reirradiation for locally recurrent rectal cancer patients with prior pelvic irradiation
The aim of the present study was to report the feasibility of proton beam reirradiation for patients with locally recurrent rectal cancer (LRRC) with prior pelvic irradiation. The study population included patients who were treated with proton beam therapy (PBT) for LRRC between 2008 and December 2019 in our institution. Those who had a history of distant metastases of LRRC, with or without treatment, before reirradiation, were excluded. Overall survival (OS), progression-free survival (PFS) and local control (LC) were estimated using the Kaplan–Meier method. Ten patients were included in the present study. The median follow-up period was 28.7 months, and the median total dose of prior radiotherapy (RT) was 50 Gy (range, 30 Gy–74.8 Gy). The median time from prior RT to reirradiation was 31.5 months (range, 8.1–96.6 months), and the median reirradiation dose was 72 Gy (relative biological effectiveness) (range, 56–77 Gy). The 1-year/2-year OS, PFS and LC rates were 100%/60.0%, 20.0%/10.0% and 70.0%/58.3%, respectively, with a median survival time of 26.0 months. Seven patients developed a Grade 1 acute radiation dermatitis, and no Grade ≥ 2 acute toxicity was recorded. Grade ≥ 3 late toxicity was recorded in only one patient, who had developed a colostomy due to radiation-related intestinal bleeding. Reirradiation using PBT for LRRC patients who had previously undergone pelvic irradiation was feasible. However, the indications for PBT reirradiation for LRRC patients need to be considered carefully due to the risk of severe late GI toxicity.
Proton beam therapy achieves excellent local control for recurrent epithelial ovarian cancer: a single-center retrospective study
Background Previous studies have demonstrated the benefit of radiation therapy for patients with recurrent epithelial ovarian cancer; however, the effects of proton beam therapy in these patients remain unelucidated. This study aimed to evaluate the use of proton beam therapy in recurrent epithelial ovarian cancer and to identify factors predictive of local control. Results This retrospective study included 13 patients with a total of 30 lesions who underwent proton beam therapy for recurrent epithelial ovarian cancer at our institution between October 2008 and March 2021. The median age of the patients at the initial proton beam therapy was 62 (range, 42–82) years. Eight patients had stage III or IV disease, and seven had serous carcinoma; ten patients exhibited platinum resistance. The irradiated sites included 16 lymph nodes and 9 pelvic or abdominal masses. The median tumor size and maximum standardized uptake value (SUVmax) of fluorine-18-fluorodeoxyglucose-positron emission tomography/computed tomography ( 18 F-FDG-PET/CT) were 25 (range, 9–83) mm and 12.6 (range, 3.9–25.1), respectively. The median total dose was 65 (range, 45–72) Gy (relative biological effectiveness). The 1- and 2-year local control were 91.5% and 71.3%, respectively. The SUVmax of 18 F-FDG-PET/CT was a significant predictor of local control (cutoff value, 17.7). The median progressing-free and overall survival after proton beam therapy initiation were 9.6 and 21.5 months, respectively. No grade 3 or higher proton beam therapy-induced adverse events were observed. Conclusion Proton beam therapy demonstrated excellent local control of recurrent epithelial ovarian cancer, with tolerable toxicity, suggesting that this modality may represent a promising treatment option. The SUVmax of 18 F-FDG-PET/CT performed prior to proton beam therapy may serve as a predictor of local control. Clinical trial number Not applicable.
Particle Beam Therapy and Surgery as Radical Treatments for Parotid Malignancies—A Single-Center Preliminary Case Study
Background/Objectives: Particle beam therapy (PBT) was approved in April 2018 for head and neck malignancies and has since been introduced as a radical therapy for parotid malignancies. However, its prevalence and effectiveness in relation to surgical treatment have not been investigated. Methods: In this study, we evaluated 36 patients with parotid malignancy who underwent surgery (n = 26) or PBT (n = 10) and then analyzed the annual changes in the number of patients, survival rates, and clinical factors affecting prognosis. Results: Of the ten patients who opted for PBT, two and eight patients underwent PBT before and after 2018, respectively. There was a significant difference between these two groups of patients (p = 0.04). Of the ten patients who underwent PBT, five patients were recurrent cases; meanwhile, all twenty-six patients who underwent surgery were receiving initial treatment. Only one patient in each group had local recurrence after the treatment. Conclusions: The use of PBT as a radical therapy for parotid malignancies has been increasing since 2018, and patients with recurrent tumors tended to choose PBT. The outcome of the patients who underwent PBT did not seem to be inferior compared with those of the patients who underwent surgery. The histopathological type was a crucial issue in the outcomes of patients who underwent radical therapy for parotid malignancies.
Radiological assessment of the skeletal remains from Hiraizumi, Japan: review of results from the 1950 investigation
Scientific investigations on the skeletal remains of four generations of the Fujiwara clan enshrined at the Chusonji World Heritage Site were carried out in March 1950. Although an official report on this investigation was published at the time, it did not merit much public attention. Thus, the purpose of this review is to describe the radiological aspects of the investigation, which may be of interest in the context of eleventh and twelfth century Japanese history.
A model-based selection of oral cancer patient for passive scattering proton beam therapy
Background and purpose: To identify patients with oral cancer (OC) who benefit from proton therapy versus photon therapy using a model-based approach (MBA) to reduce late adverse events. Material/Methods: Passive scattering proton beam therapy (PSPT) and volumetric modulated arc therapy (VMAT) plans were established for 40 patients with OC, consisting of a dose of 70 Gy (relative biological effectiveness) in 35 fractions. At least 95% of the planning target volume received 95% of the prescribed dose, and the dose to the organs at risk was restricted to be as low as possible. Normal tissue complication probability (NTCP) was used to estimate the risk of late adverse events, including dysgeusia, xerostomia and osteoradionecrosis of the mandible. Patients who were considered as candidates for PSPT were selected if the NTCP difference between both plans (ΔNTCP) exceeded the threshold defined in the Dutch national indication protocol. Results: PSPT reduced the doses to the spinal cord, pharynx, oral cavity and contralateral salivary glands compared with VMAT. PSPT was also superior for the risk evaluation of each late adverse event calculated by incorporating dose metrics and patient baseline risk factors. For the MBA using ΔNTCP and the thresholds, PSPT was indicated in 24 of the 40 cases, and the remaining 16 cases were considered to be equivalent to VMAT. Conclusion: MBA was used to select OC cases that were candidates for PSPT. Compared with VMAT, the risk of expected late adverse events was significantly reduced with PSPT, and 60% of patients were considered eligible for PSPT.
Combined intra-arterial infusion and systemic chemoradiotherapy for stage IV squamous cell carcinoma of the mandibular gingiva
Purpose The purpose of this study was to show the effectiveness of combining intra-arterial infusion and systemic chemotherapy with concurrent radiotherapy for treatment of stage IV mandibular gingival cancer. Materials and methods A total of 23 patients with mandibular gingival cancer were treated with either docetaxel by intra-arterial infusion followed by systemic chemoradiotherapy with cisplatinum and 5-fluorouracil as a monthly regimen, or with docetaxel and cisplatinum by intra-arterial infusion followed by systemic chemoradiotherapy with 5-fluorouracil as a weekly or biweekly regimen. Tumor responses, locoregional control, overall survival, disease-specific survival, and adverse events were evaluated. Results Of the 23 patients enrolled in the study, 22 completed the treatment. With regard to clinical stages, 82 % were diagnosed as IVA and 18 % IVB. Complete and partial response was observed in 82 and 18 %, respectively. Five-year overall survival, disease-specific survival, and locoregional control were 51, 70, and 72 %, respectively. No statistically significant difference was seen between the monthly regimen and the weekly plus biweekly regimen, although the latter resulted in longer survival and 88 % control. Conclusion Combined intra-arterial infusion and systemic chemoradiotherapy may be an effective treatment for patients with stage IV mandibular gingival cancer.
Proton beam therapy for external auditory canal and middle ear cancers
ABSTRACT Few studies have evaluated the efficacy of proton beam therapy (PBT) for external auditory canal cancer (EACC) or middle ear cancer (MEC). Therefore, the present study aimed to evaluate the efficacy and toxicity of PBT for EACC and MEC. Between December 2009 and August 2018, 15 patients (seven males and eight females) underwent PBT for EACC or MEC. The median patient age was 64 years (range: 40–82 years). Ten patients had EACC, and five patients had MEC. PBT was administered using the passive scattering method. The median total dose of the BED10 was 88.8 Gy relative biological effectiveness (RBE) (range = 85.6–99.3 Gy [RBE]), administered in 2 Gy fractions (EQD2) (α/β = 10). Chemotherapy was conducted in 14 patients, systemic chemotherapy in five and intra-arterial infusion chemotherapy in nine. The median follow-up period for all patients was 60 months (range: 7–136 months). The 3-year overall survival, local control and progression free survival rates were 65%, 66.7% and 53.3%, respectively. Four patients had grade 3 hearing impairment owing to late toxicity. However, these patients had hearing impairment before treatment as well. No grade 4 or higher late toxicity was observed during the follow-up period. PBT is an effective treatment for EACC and MEC with tolerable toxicity, including in the setting of combined chemotherapy.
Case report of a mental nerve neurilemmoma
We present a case of a mental neurilemmoma with characteristic findings on cone-beam computed tomography (CBCT) and magnetic resonance imaging (MRI). A 62-year-old man was referred to our hospital for a painless swelling in the right cheek. CBCT imaging demonstrated dilatation of the mental foramen. On MRI, a layered pattern on T2-weighted images and enhancement with gadolinium were observed within a low-signal pseudo-capsule. On the basis of these findings, a neurilemmoma was considered likely, and this diagnosis was confirmed histologically.