Establishment of an On-Site Dosimetric Audit Program with a Plastic Phantom.
[Establishment of an On-Site Dosimetric Audit Program with a Plastic Phantom]. Igaku Butsuri. 2020;40(3):88-96 Authors: Tani K, Wakita A Abstract The quality assurance (QA) of the output constancy of linear accelerators (linacs) is one of the most basic items for radiation therapy. The necessity and demand of the dosimetric audit is on the rise. We aimed at establishing an on-site dosimetric audit program with a plastic phantom in order to enrich the availability of dosimetric audit in Japan. By this, we developed and evaluated an on-site audit program in multiple institutions in 120 cases for photon and electron standard dosimetry and intensity modulated radiation therapy (IMRT) condition. For photon standard dosimetry, we evaluated the accuracies of institutional measured absorbed dose in 50 cases by this on-site audit program. For the electron standard dosimetry, we evaluated the accuracies of institutional measured absorbed dose in 25 cases. For IMRT condition, we evaluated the accuracies of the institutional calculated dose in radiation treatment planning systems in 45 cases. The agreements of the measured absorbed dose between our audit and the institutions were within±1.1% for photon standard dosimetry. The agreements of the measured absorbed dose between our audit and the institutions were within±2.1% for electron standard dosimetry. The agreements between the measured absorbed dose of our audit and the institutional calculated dose...
ConclusionWe trained and cross-validated an RID predictive model with high discriminative ability at both 6 and 12 months after RT. We expect to improve the predictive power of this model by enlarging the number of training datasets.
ConclusionsPlatinum ‐based chemotherapy followed by lung‐sparing surgery (P/D) and IMRT is a feasible and safe treatment modality that yields acceptable locoregional control in patients with locally advanced MPM; however, these results should be corroborated in larger studies.
Cervical cancer is the second most common cancer in women aged 15 to 44 years worldwide [1,2]. Intensity-modulated radiation therapy (IMRT) has become the preferred radiotherapy method for locally advanced cervical cancer treatment . Accurate delineation of the clinical target volume (CTV) and organ-at-risk (OAR) is one of the essential steps for successful IMRT delivery. Such delineation is conventionally performed by radiotherapy oncologists through laborious manual delineation. The delineation is time-consuming  and heavily relies on the radiotherapy oncologists ’ experience.
Normal tissue complication probability (NTCP) models that were formulated in the Quantitative Analyses of Normal Tissue Effects in the Clinic (QUANTEC) are one of the pillars in support of everyday’s clinical radiation oncology. Because of steady therapeutic refinements and the availability of cutting-edge technical solutions, the ceiling of organs-at-risk-sparing has been reached for photon-based intensity modulated radiotherapy (IMRT). The possibility to capture heterogeneity of patients and tissues in the prediction of toxicity is still an unmet need in modern radiation therapy. Potentially, a major step towards a...
PMID: 32999249 [PubMed - in process]
Prostate cancer is the most common malignancy in North American males and the second leading cause of cancer death. External beam radiation therapy plays an important role in the clinical management of prostate cancer of various stages. Currently, image-guided target localization for intensity-modulated radiation therapy (IMRT) of prostate cancer has become a routine procedure, and plays an essential role in dose escalation and hypo-fractionation clinical trials, especially for those that employ stereotactic body radiation therapy (SBRT) techniques.
Breast radiotherapy is associated with an increased risk of ischemic heart disease, particularly for left-sided irradiation due to direct anatomical proximity between the left anterior descending coronary artery (LADCA) and the target volumes [1 –4]. First generation radiotherapy techniques, which relied on wide treatment fields, were associated with a substantial cardiac mortality increase. Fortunately, breast irradiation has benefited from recent technological progresses allowing significant cardiac sparing, such as intensity-modulated radiation therapy (IMRT) , proton therapy  or deep-inspiration breath hold (DIBH).
Conditions: Cervical Carcinoma; Endometrial Carcinoma; Endometriosis; Pelvic Inflammatory Disease Interventions: Other: Quality-of-Life Assessment; Other: Questionnaire Administration; Radiation: Radiation Therapy Sponsors: Mayo Clinic; National Cancer Institute (NCI) Not yet recruiting
Authors: Nakada R, Abou Al-Ola OM, Yoshinaga T Abstract We give a novel approach for obtaining an intensity-modulated radiation therapy (IMRT) optimization solution based on the idea of continuous dynamical methods. The proposed method, which is an iterative algorithm derived from the discretization of a continuous-time dynamical system, can handle not only dose-volume but also mean-dose constraints directly in IMRT treatment planning. A theoretical proof for the convergence to an equilibrium corresponding to the desired IMRT planning is given by using the Lyapunov stability theorem. By introducing the concept of &...
Conclusions: Radiation therapy with concurrent 5-fluorouracil and mitomycin C chemotherapy is reasonably well-tolerated as curative treatment for HIV+ patients with SCAC, and no significant difference in outcomes was noted relative to HIV− patients.