title: Dose and volume impact on radiation-induced xerostomia.
abstract: Radiation-induced xerostomia consists in the chronic dryness of the mouth caused by parotid gland irradiation. Parotid glands produce approximately 60% of saliva while the rest is secreted by submandibular and accessory salivary glands. Methods of measuring the salivary output are essentially represented by 99mTc-pertechnate scintigraphy or simpler albeit less accurate methods in stimulated or unstimulated saliva. There are subjective and objective criteria of classification and grading of the secretion of saliva. Radiation-induced xerostomia, namely the residual salivary gland function is evidently associated with the mean dose absorbed. The salivary output tends to decrease after the end of radiotherapy. The partial dose-volume is substantially correlated with the mean dose to the whole gland. As for ipsilateral irradiation for head and neck cancer, conformal RT or IMRT allow to spare the contralateral parotid gland without increasing the risk of contralateral nodal recurrences. The monitoring system of late toxicity used by the authors is presented.
authors.affiliation: U.O. Radioterapia, Ospedale Fatebenefratelli S. Giovanni Calibita, Isola Tiberina, 00186 Roma, Italy. marmiroliluca@libero.it
authors.forename: Luca
authors.initials: L
authors.lastname: Marmiroli
authors.forename: Giovanna
authors.initials: G
authors.lastname: Salvi
authors.forename: Adolfo
authors.initials: A
authors.lastname: Caiazza
authors.forename: Luigi
authors.initials: L
authors.lastname: Di Rienzo
authors.forename: Mariangela
authors.initials: M
authors.lastname: Massaccesi
authors.forename: Paola
authors.initials: P
authors.lastname: Murino
authors.forename: Gabriella
authors.initials: G
authors.lastname: Macchia
mesh_terms: D004307:Dose-Response Relationship, Radiation; D006258:Head and Neck Neoplasms / Q000532:radiotherapy*; D006801:Humans; D010306:Parotid Gland / Q000000981:diagnostic imaging / Q000528:radiation effects*; D018579:Patient Selection; D011877:Radionuclide Imaging; D011879:Radiotherapy Dosage; D020266:Radiotherapy, Conformal / Q000009:adverse effects*; D012463:Saliva / Q000378:metabolism; D014987:Xerostomia / Q000000981:diagnostic imaging / Q000209:etiology* / Q000517:prevention & control