Longitudinal Changes over 2 Years in Parotid Glands of Patients Treated with Preoperative 30-Gy Irradiation for Oral Cancer
Open Access
- 12 January 2011
- journal article
- research article
- Published by Oxford University Press (OUP) in Japanese Journal of Clinical Oncology
- Vol. 41 (4), 503-507
- https://doi.org/10.1093/jjco/hyq236
Abstract
To evaluate longitudinal changes in parotid volumes and saliva production over 2 years after 30 Gy irradiation. We retrospectively evaluated 15 assessable patients treated for advanced oral cancer. Eligibility criteria were a pathologic diagnosis of squamous cell carcinoma, preoperative radiation therapy with a total dose of 30 Gy delivered in 15 fractions, and the availability of longitudinal data of morphological assessments by computed tomography and functional assessments with the Saxon test spanning 2 years after radiation therapy. In the Saxon test, saliva production was measured by weighing a folded sterile gauze pad before and after chewing; the low-normal value is 2 g/2 min. Repeated-measures analysis of variance with Bonferroni adjustment for multiple comparisons was used to determine the longitudinal changes. The normalized ipsilateral parotid volumes 2 weeks and 6-, 12- and 24 months after radiation therapy were found to be 72.5, 63.7, 66.9 and 78.1%, respectively; the normalized contralateral volumes were 69.8, 64.6, 72.2 and 82.0%, respectively. The bilateral parotid volumes were significantly decreased after radiation therapy (P < 0.01). The nadir appeared at 6 months post-radiation therapy and the volumes substantially recuperated 24 months after radiation therapy (P < 0.01). Mean saliva production before radiation therapy was 3.7 g; the longitudinal changes after radiation therapy were 31.3, 38.0, 43.3 and 69.6%, respectively. Substantial recuperation of saliva production was observed 24 months after radiation therapy (P = 0.01). Although parotid volumes and saliva production were decreased after 30 Gy irradiation, we observed the recuperation of morphological and functional changes in the parotid glands 2 years after radiation therapy.Keywords
This publication has 22 references indexed in Scilit:
- Radiation-induced Parotid Gland Changes in Oral Cancer Patients: Correlation Between Parotid Volume and Saliva ProductionJapanese Journal of Clinical Oncology, 2009
- Radiation-induced volume changes in parotid and submandibular glands in patients with head and neck cancer receiving postoperative radiotherapy: A longitudinal studyThe Laryngoscope, 2009
- Analysis of Salivary Flow and Dose–Volume Modeling of Complication Incidence in Patients With Head-and-Neck Cancer Receiving Intensity-Modulated RadiotherapyInternational Journal of Radiation Oncology*Biology*Physics, 2009
- The impact of dose on parotid salivary recovery in head and neck cancer patients treated with radiation therapyInternational Journal of Radiation Oncology*Biology*Physics, 2007
- Dose–volume modeling of salivary function in patients with head-and-neck cancer receiving radiotherapyInternational Journal of Radiation Oncology*Biology*Physics, 2005
- Long-term parotid gland function after radiotherapyInternational Journal of Radiation Oncology*Biology*Physics, 2005
- Importance of the Initial Volume of Parotid Glands in Xerostomia for Patients with Head and Neck Cancers Treated with IMRTJapanese Journal of Clinical Oncology, 2005
- Parotid and submandibular/sublingual salivary flow during high dose radiotherapyRadiotherapy and Oncology, 2001
- Late effects of radiation therapy in the head and neck regionInternational Journal of Radiation Oncology*Biology*Physics, 1995
- A quantitative test for xerostomia. The saxon test, an oral equivalent of the schirmer testArthritis & Rheumatism, 1985