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The results of clinical trials in the treatment of adenocarcinoma of the prostate using, mixed beam neutron/photon therapy, neutrons alone and photon therapy in combination with hormone treatment are compared. These trials indicate that neutron therapy is superior to photon/hormone therapy in achieving local control. The costs of delivering these two different therapies in a large US academic radiation oncology center at Wayne State University (WSU) are compared. The cost of a full course of mixed beam therapy is $20,142 compared to $18,871 for the photon/hormone treatment. Although the WSU neutron facility is a state-of-the-art installation, it is also a prototype device; it is estimated that a modern neutron facility based on this design would operate more cost effectively reducing the cost of a course of mixed beam therapy to $18,532. [ABSTRACT FROM AUTHOR]

The use of paired proportional counters, constructed from A-150 tissue equivalent plastic (TEP) and A-150 TEP loaded with an appropriate amount of 10B (50 to 200 ppm), for the dosimetry of the boron neutron capture reaction has been investigated for several years at the Gershenson Radiation Oncology Center. This method has been used for determining the dose components (fast neutron, gamma ray and boron capture product dose) in both Boron Neutron Capture Therapy (BNCT) beams and in beams proposed for boron neutron capture enhancement of fast neutron therapy (BNCEFNT). A disadvantage of this method, when standard 1/2" diameter Rossi type proportional counters are used, is that the beam intensity must be relatively low in order to avoid saturation effects (pulse pile-up) in the counter. This is a major problem if measurements are to be made in a reactor beam, since reducing the beam intensity generally results in a change in the neutron spectrum. In order to overcome this problem, miniature cylindrical proportional counters have been developed which may be used in high intensity beams. The operational characteristics of these counters are compared with the standard 1/2" spherical counters. A further disadvantage of proportional counters is the relatively long time it takes to collect data, particularly if detailed information (depth-dose curves and beam profiles) is required. This problem could be overcome by using a set of ionization chambers (an A-150 TEP chamber, a Mg chamber and a Mg chamber with a 25 microns boron loaded inner wall) which can be scanned in a water phantom. After calibration against the paired proportional counters it should be possible to extract the fast neutron, gamma ray and boron neutron capture product doses from measurements made with these three ionization chambers. A set of such chambers has been used to make preliminary measurements in a fast neutron beam and the results of these measurements are presented. [ABSTRACT FROM AUTHOR]