Dosimetric considerations in the treatment of inoperable endometrial carcinoma by a high dose rate afterloading packing technique.

A series of 23 patients with early adenocarcinoma of the endometrium who underwent a total of 37 modified Heyman packings treated on a high dose rate Microselectron has been reviewed. Using computed tomography (CT), the uterine wall thickness was measured retrospectively and doses calculated at a number of points on the uterine serosa and related normal tissues. The mean and maximum fundal serosal doses were found to be highest posteriorly and the sigmoid colon was adjacent to the posterior surface of the uterus in all instances. By superimposing the isodose distribution on CT sections of the uterus, it is now possible to prescribe to a serosal dose, or, in patients too heavy for the CT scanner, a dose can be prescribed to a point S, which is a reasonable approximation to the serosal position. Since the initial study, a further ten patients have been treated by the same method and, where relevant, data from all 33 patients have been used.