ABSTRACT
Brachytherapy and particle therapy are often compared and considered as rival techniques in radiation oncology. On the other hand, when compared to advanced photon beam therapy, both techniques have several common features. Brachytherapy and particle therapy allow achieving highly conformal dose distributions, with dose gradients being much steeper than the ones typical for high-energy photon beam therapy. In brachytherapy, if there is a rigid link between applicator and the clinical target volume (CTV), such a link reduces the need for a margin for intra-fraction effects orthogonal to the longitudinal source axis. There are important radiobiological aspects due to effects from fractionation and overall treatment time when comparing external beam photon therapy, particle therapy, and brachytherapy. Prostate carcinoma and uveal melanoma are the two major primary indications where brachytherapy and particle therapy are recognized at present as competing techniques with rather comparable clinical outcome.
