Carcinoma of the maxillary sinus extends into various directions according to the individual. One standard dose distribution cannot satisfy each patient when extended into various directions. A study was made and sub-standard dose distribution patterns were obtained for each direction of the extension, using a radiotherapy planning computer (MODULEX) and ^<60>Co gamma-ray data. Extension modes were classified into 8 types. In cases for the standard type, we used 2 evenly weighted wedge-paired portals, one : AP and another : lateral oblique, with a set depth of 4.5cm. Portal width : 8cm in AP and 8cm in lateral oblique. Cross angle of the beams : 75°, Degree of the wedge filters : 45°each. The eye balls and brain were shielded as much as possible. Planning patterns differed according to various types of extension. These patterns were used for each patient at the beginning of the radiotherapy, with the information of extension direction but without obtaining planning CT, or computer processing.
