Whole-brain Irradiation Field Design: A Comparison of Parotid Dose

Assessment of Risk of Xerostomia After Whole-Brain Radiation Therapy and Association With Parotid Dose

“…More recent dosimetric studies in the era of 3-D planning (that makes possible the delineation and avoidance of organs at risk) report parotid doses of 15 to 20 Gy during WBRT, but these studies did not record clinical outcomes. [15][16][17][18][19][20] Therefore, the clinical significance of this parotid exposure is unknown, and the parotid glands are not routinely delineated or avoided during WBRT. 25,28 In contrast, radiation therapy for head and neck cancer is well known to be associated with substantial and sometimes permanent xerostomia.…”

“…In 1980, Cairncross et al described acute parotitis with accompanying hyperamylasemia in 4 patients. More recent dosimetric studies in the era of 3-D planning (that makes possible the delineation and avoidance of organs at risk) report parotid doses of 15 to 20 Gy during WBRT, but these studies did not record clinical outcomes . Therefore, the clinical significance of this parotid exposure is unknown, and the parotid glands are not routinely delineated or avoided during WBRT .…”

“…For head and neck radiation therapy, numerous studies over several decades have illustrated the importance of limiting radiation dose to the parotid glands to minimize dry mouth and improve QOL . However, the parotid glands are not typically delineated nor avoided during WBRT, despite receiving substantial doses …”

“…[9][10][11][12][13][14] However, the parotid glands are not typically delineated nor avoided during WBRT, despite receiving substantial doses. [15][16][17][18][19][20] We hypothesized that WBRT is associated with clinically significant xerostomia and that xerostomia is associated with parotid dose. To investigate this hypothesis, we conducted a prospective observational study of patients receiving routine WBRT.…”

Prospective Assessment of Patient-Reported Dry Eye Syndrome After Whole Brain Radiation

“…Standard WBRT techniques have not changed appreciably for decades, and the routine practice of designing radiation fields to encompass the upper cervical vertebrae and the cribiform plate results in dose to the parotid and lacrimal glands, respectively. 8,[18][19][20][21] Figure 4A shows the radiation fields used to treat a study patient who developed persistent dry eye symptoms. In Figure 4B, the radiation fields were re-designed to spare the lacrimal glands.…”