Dosimetric Comparison Study of Proton Therapy Using Line Scanning versus Passive Scattering and Volumetric Modulated Arc Therapy for Localized Prostate Cancer.

Background: The proton irradiation modality has transitioned from passive scattering (PS) to pencil beam scanning. Nevertheless, the documented outcomes predominantly rely on PS.

Methods: Thirty patients diagnosed with prostate cancer were selected to assess treatment planning across line scanning (LS), PS, and volumetric modulated arc therapy (VMAT).

Proton Beam Therapy for Hepatocellular Carcinoma: Multicenter Prospective Registry Study in Japan.

Purpose: A prospective multicenter registry study was started May 2016 in Japan to evaluate the efficacy and safety of proton beam therapy (PBT) for hepatocellular carcinoma (HCC).

Methods And Materials: Patients who received PBT for HCC from May 2016 to June 2018 were registered in the database of the Particle Beam Therapy Committee and Subcommittee of the Japanese Society for Radiation Oncology. Overall survival (OS), progression-free survival (PFS), and local recurrence were evaluated.

Proton beam therapy for extrahepatic biliary tract cancer: Analysis with prospective multi-institutional patients' registration database, Proton-Net.

Background And Purpose: To examine the role of proton beam therapy (PBT) in the treatment of extrahepatic biliary tract cancer (EBC).

Methods And Materials: We analyzed the data accumulated in the Proton-Net database, which prospectively registered all individual patient data treated with PBT in all Japanese proton institutions from May 2016 to June 2019. The primary endpoint was overall survival (OS), and the secondary endpoints were local control (LC), progression-free survival (PFS), and toxicity.

Proton beam therapy for muscle-invasive bladder cancer: A systematic review and analysis with Proton-Net, a multicenter prospective patient registry database.

To assess the safety and efficacy of proton beam therapy (PBT) for muscle-invasive bladder cancer (MIBC), we examined the outcomes of 36 patients with MIBC (cT2-4aN0M0) who were enrolled in the Proton-Net prospective registry study and received PBT with concurrent chemotherapy from May 2016 to June 2018. PBT was also compared with X-ray chemoradiotherapy in a systematic review (X-ray (photon) radiotherapy). The radiotherapy consisted of 40-41.

Particle Beam Therapy for Intrahepatic and Extrahepatic Biliary Duct Carcinoma: A Multi-Institutional Retrospective Data Analysis.

To examine the efficacy and toxicity of particle beam therapy (PT) for biliary duct carcinoma (BDC) and compare the outcomes between extrahepatic BDC (eBDC) and intrahepatic BDC (iBDC). We analyzed multi-institutional data from May 2009 to December 2019. The primary endpoint was overall survival (OS), and the secondary endpoints were local control (LC), progression-free survival (PFS) and toxicity.

Complete Response Induced by Concurrent Chemoradiotherapy in a Patient with NUT Carcinoma.

An 18-year-old man presented with sudden vision loss in his left eye. Magnetic resonance imaging revealed a tumor that had invaded the left optic nerve, originating from the left posterior ethmoid sinus. Immunohistochemical analyses identified positive staining for NUT protein in the nuclei of tumor cells.

Proton Therapy for Localized Prostate Cancer: Long-Term Results From a Single-Center Experience.

Purpose: Although proton therapy is controversial, it has been used to treat localized prostate cancer over the past 2 decades. The purpose of this study is to examine the long-term efficacy and toxicity of proton therapy for localized prostate cancer.

Methods And Materials: This was a retrospective observational study of 2021 patients from 2003 to 2014 at a single institution.

Evaluation of the urethral α/β ratio and tissue repair half-time for iodine-125 prostate brachytherapy with or without supplemental external beam radiotherapy.

Purpose: To assess the correlation between postimplant dosimetric quantifiers and the genitourinary (GU) toxicity of low-dose rate brachytherapy for prostate cancer.

Methods And Materials: The minimum urethral dose (UD10, 30, and 90) and the percent volume of the urethra receiving the prescription dose (V100, V150) were calculated from the postimplant dose-volume histograms of 182 patients. We then calculated various urethral biologically equivalent doses (uBEDs) using different values of the α/β ratio and tissue repair half-time (t1/2) and examined the correlations with GU toxicity.

Treatment outcomes of proton or carbon ion therapy for skull base chordoma: a retrospective study.

Background: The usefulness of particle therapy for skull base chordoma has not been established. The aim of this retrospective study was to analyse the treatment outcomes of proton therapy (PT) and carbon ion therapy (CIT) in patients with skull base chordoma at a single institution.

Methods: All patients who underwent PT or CIT with curative intent between 2003 and 2014 at Hyogo Ion Beam Medical Center were included in this study.

Long-term outcomes of proton therapy for prostate cancer in Japan: a multi-institutional survey of the Japanese Radiation Oncology Study Group.

This is the first multi-institutional retrospective survey of the long-term outcomes of proton therapy (PT) for prostate cancer in Japan. This retrospective analysis comprised prostate cancer patients treated with PT at seven centers between January 2008 and December 2011 and was approved by each Institutional Review Board. The NCCN classification was used.

Long-term outcomes in patients treated with proton therapy for localized prostate cancer.

The aim of this retrospective study was to report long-term clinical outcomes in patients treated with proton therapy (PT) for localized prostate cancer. Between 2001 and 2014, 1375 consecutive patients were treated with PT. Patients were classified into prognostic risk groups based on the National Comprehensive Cancer Network criteria.

Relation between Ku80 and microRNA-99a expression and late rectal bleeding after radiotherapy for prostate cancer.

Background And Purpose: Late rectal bleeding is one of the severe adverse events after radiotherapy for prostate cancer. New biomarkers are needed to allow a personalized treatment.

Materials And Methods: Four patients each with grade 0-1 or grade 2-3 rectal bleeding were randomly selected for miRNA array to examine miRNA expression in peripheral blood lymphocytes (PBLs).

Treatment outcomes of particle radiotherapy using protons or carbon ions as a single-modality therapy for adenoid cystic carcinoma of the head and neck.

Background And Purpose: The aim of this study was to retrospectively analyse the outcomes of cases of adenoid cystic carcinomas (ACCs) of the head and neck that were treated at a single institution with particle therapy consisting of either protons or carbon ions.

Methods And Materials: Between February 2002 and March 2012, 80 patients were treated with proton therapy (PT) or carbon ion therapy (CIT) alone. PT and CIT were employed in 40 (50%) patients each, and more than half of the patients received 65.

Particle therapy for clinically diagnosed stage I lung cancer: comparison with pathologically proven non-small cell lung cancer.

Background: The purpose of the present study was to present the treatment outcomes of particle therapy for indeterminate pulmonary nodules (IPNs) diagnosed as stage I non-small cell lung cancer, including a comparative analysis involving pathologically proven lung cancer (PPLC).

Material And Methods: A total of 54 patients (57 lesions) who underwent particle therapy for IPNs were enrolled in this study. Median patient age was 76 (range 52-87) years.

Results and DVH analysis of late rectal bleeding in patients treated with 3D-CRT or IMRT for localized prostate cancer.

In patients undergoing radiotherapy for localized prostate cancer, dose-volume histograms and clinical variables were examined to search for correlations between radiation treatment planning parameters and late rectal bleeding. We analyzed 129 patients with localized prostate cancer who were managed from 2002 to 2010 at our institution. They were treated with 3D conformal radiation therapy (3D-CRT, 70 Gy/35 fractions, 55 patients) or intensity-modulated radiation therapy (IMRT, 76 Gy/38 fractions, 74 patients).

Strength estimation of a moving 125Iodine source during implantation in brachytherapy: application to linked sources.

This study sought to demonstrate the feasibility of estimating the source strength during implantation in brachytherapy. The requirement for measuring the strengths of the linked sources was investigated. The utilized sources were (125)I with air kerma strengths of 8.

A dosimetry method for low dose rate brachytherapy by EGS5 combined with regression to reflect source strength shortage.

The post-implantation dosimetry for brachytherapy using Monte Carlo calculation by EGS5 code combined with the source strength regression was investigated with respect to its validity. In this method, the source strength for the EGS5 calculation was adjusted with the regression, so that the calculation would reproduce the dose monitored with the glass rod dosimeters (GRDs) on a water phantom. The experiments were performed, simulating the case where one of two (125)I sources of Oncoseed 6711 was lacking strength by 4-48%.

A retrospective comparison of proton therapy and carbon ion therapy for stage I non-small cell lung cancer.

Background And Purpose: This retrospective study aimed to compare the clinical outcomes and late toxicities of proton therapy (PT) with those of carbon ion therapy (CIT) for stage I non-small cell lung cancer (NSCLC).

Material And Methods: A total of 111 patients who underwent particle therapy for stage I NSCLC between April 2003 and December 2009 were enrolled in this study. PT (n=70) and CIT (n=41) were delivered to total doses of 52.

Measurement of the strength of iodine-125 seed moving at unknown speed during implantation in brachytherapy.

The aim of this study is to demonstrate the feasibility of estimating the strength of the moving radiation source during patient implantation. The requirement for the counting time was investigated by comparing the results of the measurements for the static source with those for the source moving at 2, 5, 10 and 20 cm s(-1). The utilized source was (125)I with an air-kerma strength of 0.

Phase I study of oral S-1 and concurrent radiotherapy in patients with head and neck cancer.

This study investigated the maximum tolerated dose (MTD) of S-1 with concurrent radiotherapy in patients with head and neck cancer, based on the frequency of dose-limiting toxicities (DLT). S-1 was administered orally at escalating doses from 40 mg/m(2) b.i.

Analysis and results of Ku and XRCC4 expression in hypopharyngeal cancer tissues treated with chemoradiotherapy.

DNA double-strand break (DSB) is one of the most serious forms of damage induced by ionizing irradiation. Non-homologous end-joining (NHEJ) is a key mechanism of DNA DSB repair. The immunohistochemical analysis of proteins involved in NHEJ may have potential as a predictive assay for tumor radiosensitivity.

A dosimetry study of the Oncoseed 6711 using glass rod dosimeters and EGS5 Monte Carlo code in a geometry lacking radiation equilibrium scatter conditions.

Purpose: The aim of this study was to develop a dose calculation method which is applicable to the interseed attenuation and the geometry lacking the equilibrium radiation scatter conditions in brachytherapy.

Methods: The dose obtained from measurement with a radiophotoluminescent glass rod dosimeter (GRD) was compared to the dose calculated with the Monte Carlo (MC) code "EGS5," using the 125I source structure detailed in by Kennedy et al. The GRDs were irradiated with 125I Oncoseed 6711 in a human head phantom.

Gimeracil, an inhibitor of dihydropyrimidine dehydrogenase, inhibits the early step in homologous recombination.

Gimeracil (5-chloro-2, 4-dihydroxypyridine) is an inhibitor of dihydropyrimidine dehydrogenase (DPYD), which degrades pyrimidine including 5-fluorouracil in the blood. Gimeracil was originally added to an oral fluoropyrimidine derivative S-1 to yield prolonged 5-fluorouracil concentrations in serum and tumor tissues. We have already reported that gimeracil had radiosensitizing effects by partially inhibiting homologous recombination (HR) in the repair of DNA double strand breaks.