Decreased pituitary gland height after radiation treatment to the hypothalamic-pituitary axis evaluated by MR.

PURPOSE To evaluate treatment-related changes in pituitary gland morphology after childhood cancer and to compare these findings with growth data. METHODS Forty-three survivors of childhood cancer were evaluated by cranial MR imaging. Twenty-nine of the patients had received radiation therapy to the hypothalamic-pituitary axis with doses of 10 to 46 Gy. The height of the pituitary gland was measured from midline sagittal images and compared with age- and sex-matched controls. Pituitary gland heights were compared with body height standard deviation scores in patients. RESULTS The patients who had received radiation therapy to the hypothalamic-pituitary axis had significantly smaller pituitary glands than patients in the nonirradiated group or their age- and sex-matched controls (mean, 3.5 mm versus 5.9 and 5.8 mm, respectively). They were also significantly shorter than patients in the nonirradiated group. CONCLUSION Radiation therapy to the hypothalamic-pituitary area may lead to poor growth of the pituitary gland and short stature.