Experience with Treating Lentigo Maligna with Definitive Radiotherapy

Figure 4

Radiotherapy modalities include external beam radiotherapy (EBRT) or brachytherapy (BT). These two classes of modalities are related by the inverse square law. Inverse square law states that as one moves away from the radioactive source, the amount of radiotherapy that can be measured is inversely proportional to the square of the distance.