IMRT is a rapidly evolving technique, which affords a more precise radiation dose delivery of escalated doses, in appropriate cases, to targeted tumors, while sparing nearby healthy tissue structures. The FDA clearance of numerous devices for the technical delivery of IMRT is based on the capability of this technology to incorporate accurate dose calculation algorithms, associated with a verifiable dose distribution, as managed by the treating physician, (i.e., radiation oncologist). Although, to date, no randomized trials have matured to document long-term outcomes data and efficacy for IMRT, the scientific evidence currently available indicates that IMRT permits better treatment planning and sparing of surrounding tissues, which is of particular usefulness with “Radiosensitive” tumors of the head/neck, prostate and CNS lesions where the target volume is in close proximity to critical healthy structures that must be protected. These results may be extrapolated to the treatment of other cancers at other anatomic sites; however, a number of technical issues need to be resolved before IMRT can be recommended routinely for lung cancer use, particularly the issue of tumor mobility must be addressed, (e.g., a lung tumor moving with respiration)” . CCited from: htttp://atc.wustl.edu/home/NCI/NCI_IMRT_Guidelines_2006.pdf
Currently, there are no randomized controlled trials of IMRT compared with other radiation techniques for treatment of prostate cancer. Non-randomized studies consistently demonstrate reduced rates of toxicity in IMRT-treated patients. The 2010 Agency for Healthcare Research and Quality (AHRQ) comparative evaluation of radiation treatments for clinically localized prostate cancer concluded that data on comparative effectiveness between different forms of radiation treatments are inconclusive with respect to overall or disease-specific survival. In addition, the AHRQ technology assessment states that more studies of better quality are needed to confirm or refute the suggested findings in the studies that compared outcomes in patients treated with different forms of radiation therapy.
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Zelefsky, MJ, Levin, EJ, Hunt, M, et al. Incidence of late rectal and urinary toxicities after three-dimensional conformal radiotherapy and intensity-modulated radiotherapy for localized prostate cancer. Int J Radiat Oncol Biol Phys. 2008 Mar 15;70(4):1124-9.
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