In cancer research, well characterized small animal models of human cancer, such as transgenic mice, have greatly accelerated the pace of development of cancer treatments. The goal of the Small Animal Radiation Research Platform (SARRP) is to make those same models...
This addendum to the code of practice for the determination of absorbed dose for x-rays below 300 kV has recently been approved by the IPEM and introduces three main changes: (i) Due to a lack of available data the original code recommended a value of unity for kch in the very-low-energy range (0.035–1.0 mm Al HVL). A single table of kch values, ranging from 1.01 to 1.07, applicable to both designated chamber types is now presented. (ii) For medium-energy x-rays (0.5–4 mm Cu HVL) methods are given to determine the absorbed dose to water either at 2 cm depth or at the surface of a phantom depending on clinical needs. Determination of the dose at the phantom surface is derived from an in-air measurement and by extending the low-energy range up to 4 mm Cu HVL. Relevant backscatter factors and ratios of mass energy absorption coefficients are given in the addendum. (iii) Relative dosimetry: although not normally forming part of a dosimetry code of practice a brief review of the current literature on this topic has been added as an appendix. This encompasses advice on techniques for measuring depth doses, applicator factors for small field sizes, dose fall off with increasing SSD and choice of appropriate phantom materials and ionization chambers.
R J Aukett, J E Burns, A G Greener, R M Harrison, C Moretti, A E Nahum and K E Rosser
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With the significant increase in the average life-span in the industrial world, skin cancer has become a great health concern. There are various epidemiological, biological and molecular data suggesting that skin cancer is predominantly a disease of the elderly, since...
PURPOSE: We report on our experience in the treatment of T1 and T2 mycosis fungoides (MF) with total skin electron beam therapy (TSEBT), with respect to relapse-free rate, overall survival rate, and management of recurrence. METHODS AND MATERIALS: Between 1975 and...
PURPOSE: To determine the outcomes of patients with locally advanced basal cell and squamous cell carcinomas of the skin treated with radiotherapy. METHODS AND MATERIALS: A retrospective review of the outcomes of patients with basal cell and squamous cell carcinomas...
BACKGROUND: The histologic subtype of a basal cell carcinoma (BCC) may be an important factor for the success of a certain treatment modality. In the current article, the authors report recurrence rates among patients with BCC after superficial radiotherapy as well as...
Radiotherapy is an important modality in the treatment of non-melanoma skin cancers. While the majority of patients will be adequately treated without the need for radiotherapy, there are factors that may favour a recommendation for radiotherapy. The established roles...
BACKGROUND: Assuming interinstitutional differences in the treatment of bone metastases, a survey of German radiotherapy institutions was carried out. The goal was to demonstrate regional strategies in pretherapeutic diagnosis, radiation treatment, and follow-up....
This new code of practice for the determination of absorbed dose for x-rays below 300 kV has recently been approved by the IPEMB and introduces the following changes to the previous codes: (i) The determination of absorbed dose is based on the air kerma determination (exposure measurement) method. (ii) An air kerma calibration factor for the ionization chamber is used. (iii) The use of the F (rad/röentgen) conversion factor is abandoned and replaced by the ratio of the mass – energy absorption coefficients of water and air for converting absorbed dose to air to absorbed dose to water. New values for ratios of these coefficients are recommended. Perturbation and other correction factors are incorporated in the equations. (iv) New backscatter factors are recommended. (v) Three separate energy ranges are defined, with specific procedures for each range. These ranges are: (a) 0.5 to 4 mm Cu HVL; for this range calibration at 2 cm depth in water with a thimble ion chamber is recommended. (b) 1.0 to 8.0 mm Al HVL; for this range calibration in air with a cylindrical ion chamber and the use of tabulated values of the backscatter factor are recommended. (c) 0.035 to 1.0 mm Al HVL; for this range calibration on the surface of a phantom with a parallel-plate ionization chamber is recommended.
S C Klevenhagen, R J Aukett, R M Harrison, C Moretti, A E Nahum and K E Rosser
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