Physics-aspects of dose accuracy in high dose rate (HDR) brachytherapy: source dosimetry, treatment planning, equipment performance and in vivo verification techniques

Aim of this work is to calibrate the high dose rate (HDR) brachytherapy source 60Co. The radioactive source calibration is a very important part of the quality assurance program for dosimetry of brachytherapy source. The goal of this project is the calibration of HDR Brachytherapy source in radiation therapy is the measurement of the air kerma rate which required actual dose to deliver. The source calibration is an essential part of the quality assurance program for dosimetry of brachytherapy source. This research will help the patient who is involving brachytherapy treatment. HDR brachytherapy source 60Co is inserted directly or in close to the tumor. Most commonly using method for calibration of HDR brachytherapy source 60CO is well type ionization chamber. Calibration of the radioactive source 60Co brachytherapy source is very important for the treatment of cancer patient. We have got the variation between RAKR from TPS and measured Air Kerma Rate of 60Co brachytherapy source are 3.2% and 3.04% and which give very good agreement with the Air Kerma Rate (RAKR) is 5% (from BEBIG protocol, Germany). So, our results were satisfied for brachytherapy treatment. From these results, it must be concluded that, 60Co brachytherapy source is suitable for brachytherapy cancer treatment. It is very difficult to calculate treatment deliver dose without calibrating AKR of HDR brachytherapy source. It is very important to verify the calculated Air Kerma Rate by TPS Air Kerma Rate.

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Impact of High-Dose-Rate Brachytherapy Training via Telehealth in Low- and Middle-Income Countries

JCO Global Oncology ◽

10.1200/go.20.00302 ◽

2020 ◽

pp. 1803-1812

Author(s):

Jeremy B. Hatcher ◽

Oluwadamilola Oladeru ◽

Betty Chang ◽

Sameeksha Malhotra ◽

Megan Mcleod ◽

...

Keyword(s):

Dose Rate ◽

Treatment Planning ◽

High Dose Rate ◽

High Dose ◽

Hdr Brachytherapy ◽

Middle Income ◽

Middle Income Countries ◽

Radiation Oncologists ◽

Medical Physicists ◽

Low And Middle Income

PURPOSE Our objective was to demonstrate the efficacy of a telehealth training course on high-dose-rate (HDR) brachytherapy for gynecologic cancer treatment for clinicians in low- and middle-income countries (LMICs) METHODS A 12-week course consisting of 16 live video sessions was offered to 10 cancer centers in the Middle East, Africa, and Nepal. A total of 46 participants joined the course, and 22 participants, on average, attended each session. Radiation oncologists and medical physicists from 11 US and international institutions prepared and provided lectures for each topic covered in the course. Confidence surveys of 15 practical competencies were administered to participants before and after the course. Competencies focused on HDR commissioning, shielding, treatment planning, radiobiology, and applicators. Pre- and post-program surveys of provider confidence, measured by 5-point Likert scale, were administered and compared. RESULTS Forty-six participants, including seven chief medical physicists, 16 senior medical physicists, five radiation oncologists, and three dosimetrists, representing nine countries attended education sessions. Reported confidence scores, both aggregate and paired, demonstrated increases in confidence in all 15 competencies. Post-curriculum score improvement was statistically significant ( P < .05) for paired respondents in 11 of 15 domains. Absolute improvements were largest for confidence in applicator commissioning (2.3 to 3.8, P = .009), treatment planning system commissioning (2.2 to 3.9, P = .0055), and commissioning an HDR machine (2.2 to 4.0, P = .0031). Overall confidence in providing HDR brachytherapy services safely and teaching other providers increased from 3.1 to 3.8 and 3.0 to 3.5, respectively. CONCLUSION A 12-week, low-cost telehealth training program on HDR brachytherapy improved confidence in treatment delivery and teaching for clinicians in 10 participating LMICs.

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High–dose rate brachytherapy in the treatment of carcinoma of uterine cervix: twenty-year experience with cobalt after-loading system

International Journal of Gynecological Cancer ◽

10.1136/ijgc-00009577-200605000-00024 ◽

2006 ◽

Vol 16 (3) ◽

pp. 1101-1105

Author(s):

A. Mosalaei ◽

M. Mohammadianpanah ◽

S. Omidvari ◽

N. Ahmadloo

Keyword(s):

Dose Rate ◽

Treatment Planning ◽

Uterine Cervix ◽

Locally Advanced ◽

Disease Free Survival ◽

High Dose Rate ◽

High Dose ◽

Hdr Brachytherapy ◽

Gastrointestinal Complications ◽

Fractionation Schedule

This retrospective analysis aims to report results of patients with cancer of uterine cervix treated with external-beam radiotherapy (EBR) and high–dose rate (HDR) brachytherapy, using manual treatment planning. From 1975 to 1995, 237 patients with FIGO stages IIB–IVA and mean age of 54.31 years were treated. EBR dose to the whole pelvis was 50 Gy in 25 fractions. Brachytherapy with HDR after-loading cobalt source (Cathetron) was performed following EBR completion with a dose of 30 Gy in three weekly fractions of 10 Gy to point A. Survival, local control, and genitourinary and gastrointestinal complications were assessed. In a median follow-up of 60.2 months, the 10-year overall and disease-free survival rate was 62.4%. Local recurrence was seen in 12.2% of patients. Distant metastases to the lymph nodes, peritoneum, lung, liver, and bone occurred in 25.3% of patients. Less than 6% of patients experienced severe genitourinary and/or gastrointestinal toxicity that were relieved by surgical intervention. No treatment-related mortality was seen. This series suggests that 50 Gy to the whole pelvis together with three fractions of 10 Gy to point A with HDR brachytherapy is an effective fractionation schedule in the treatment of locally advanced cancer of cervix. To decrease the complications, newer devices and treatment planning may be beneficial.

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