Not only suspicious areas for microscopic disease can be boosted but also critical normal structures such as bowel, nerves, and ureters can be protected from unnecessary radiation. The DP expands the limitation of the retangular HAM applicator and makes it possible http://www.selleckchem.com/Androgen-Receptor.html to create more geometrically complex treatment areas. However, this entails the use of a template to delineate the target
area as well as more complex treatment planning, which could potentially result in a slightly lengthened procedure; thus, one should carefully identify the ideal candidate to use this nonuniform HDR-IORT technique. Finally, another drawback of this more complicated approach is that there is a greater potential for error regarding directionality of the HAM because it was no longer a uniform dose distribution. Although other centers have advocated IOERT [2], [9] and [10], this technique Selleckchem Erlotinib is not always feasible in certain sites owing to anatomic limitations [3] and [8]. Moreover, IOERT does not allow “DP” in the same manner achieved
by HDR-IORT using the HAM applicator. Harrison et al. (4) initially described our results using the HAM applicator to deliver HDR-IORT in 1995. In our experience, this flexible applicator is more advantageous because it can be molded to the tumor bed and allows more conformal treatment on curved surfaces. Moreover, the technique is relatively simple and the time to position the applicator is low. Lead shields and wet lap pads are often used to protect and displace normal organs from the target area to reduce the dose to the radiosensitive organs and structures in the pelvis. Nevertheless, complications such as ureteral stenosis, bowel obstruction, and neuropathy have been previously reported (11); thus lead shields and lap pads may not be sufficient to
protect adjacent highly radiosensitive structures, and the use of the HAM applicator for dose de-escalation should be encouraged to avoid Methocarbamol high doses to areas at higher risk of complication. The potential for severe late complications related to a single high dose remains a concern [8] and [12] because the classic principles of radiobiology, sublethal damage repair, reoxygenation of hypoxic cells, and redistribution of cells in the cell cycle are not exploited. Haddock et al. (2) reported in reirradiated patients with colorectal cancer using IOERT that doses exceeding 12.5 Gy in a single fraction were associated with increased incidence and severity of neuropathy. Other common IOERT-related complications included wound infection, gastrointestinal tract fistula, and ureteral obstruction.