Radiation therapy fields for cervical cancer

Conventional anteroposterior, AP (A), and lateral (B) radiation portals for cervical cancer defined by a superior field border at the L4-L5 disk space, a inferior border extending 3 to 4 cm below the lowest extent of disease or the bottom of the obturator foramen, and a lateral edge 1.5 to 2 cm lateral to the pelvic brim.