Dosimetric Evaluation of the Uterus in Patients Receiving Total Body Irradiation with Ovarian Shielding

Abstract

Infertility is a well-known late complication in patients receiving hematopoietic stem cell transplantation (HSCT). We previously reported that total body irradiation (TBI) with ovarian shielding reduces the radiation dose to the ovaries to 2.4 Gy – one-fifth of the dose compared to conventional TBI – and preserves fertility without increasing the risk of relapse. Exposure to the uterus and ovaries can reportedly affect pregnancy and childbirth. However, the dose constraint of the uterus that causes infertility remains unknown. Herein, we report the pregnancy and birth outcomes of 2 patients who gave birth following TBI with ovarian shielding and evaluated the dose to the uterus using a dose-volume histogram. Case 1 involved a 30-year-old woman with acute myeloid leukemia who underwent HSCT at 21 years of age with a uterus mean dose (<i>D</i>_mean) of 7.0 Gy. She had a natural pregnancy and elective cesarean section at 38 weeks of gestation due to hypertensive disorders of pregnancy. She gave birth to a normal-birthweight infant. Case 2 involved a 32-year-old woman with T-cell acute lymphoblastic leukemia who underwent HSCT at 30 years of age with a uterus <i>D</i>_mean of 7.6 Gy. Her baby was delivered at full term with normal birthweight. These results indicate that a uterus <i>D</i>_mean between 7.0 and 7.6 Gy does not have a significant impact on pregnancy and delivery with the ovarian function being preserved for patients who received TBI with ovarian shielding after puberty.