Impact of Salivary Gland Dosimetry on Post-IMRT Recovery of Saliva Output and Xerostomia Grade for Head-and-Neck Cancer Patients Treated With or Without Contralateral Submandibular Gland Sparing: A Longitudinal Study

Journal Article · Thu Dec 01 04:00:00 EST 2011 · International Journal of Radiation Oncology, Biology and Physics

DOI:https://doi.org/10.1016/J.IJROBP.2010.07.1990· OSTI ID:22054509

Zhonghe, Wang; Chao, Yan ^[1]; Zhiyuan, Zhang; Chenping, Zhang ^[2]; Haisheng, Hu; Wenyong, Tu ^[1]; Kirwan, Jessica ^[3]

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1. Division of Radiation Oncology, the Shanghai Ninth Peoples Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai (China)
2. Department of Oral and Maxillofacial Surgery, the Shanghai Ninth Peoples Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai (China)
3. Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, Florida (United States)

Purpose: To observe the recovery of saliva output and effect on xerostomia grade after intensity-modulated radiotherapy (IMRT) with or without contralateral submandibular gland (cSMG) sparing and to assess the impact of salivary gland dosimetry on this recovery among patients with head-and-neck cancer. Methods and Materials: Between May 2007 and May 2008, 52 patients with head-and-neck cancer received definitive (n = 5 patients) and postoperative (n = 47 patients) IMRT at our institution, with at least one parotid gland spared. Of these patients, 26 patients with a low risk of recurrence in the cSMG region underwent IMRT and had their cSMGs spared (cSMG-sparing group). The remaining 26 high-risk patients had no cSMGs spared (cSMG-unspared group). Xerostomia grades and salivary flow rates were monitored at five time points (before IMRT and at 2, 6, 12, and 18 months after IMRT). Results: Average mean doses and mean volumes receiving 30 Gy (V30) of the cSMGs were lower in the cSMG-sparing group than in the cSMG-unspared group (mean dose, 20.4 Gy vs. 57.4 Gy; mean V30, 14.7% vs. 99.8%, respectively). Xerostomia grades at 2 and 6 months post-IMRT were also significantly lower among patients in the cSMG-sparing group than in the cSMG-unspared group, but differences were not significant at 12 and 18 months after IMRT. Patients in the cSMG-sparing group had significantly better mean unstimulated salivary flow rates at each time point post- IMRT as well as better mean stimulated salivary flow rates at 2 months post-IMRT. Conclusions: Recovery of saliva output and grade of xerostomia post-IMRT in patients whose cSMGs were spared were much better than in patients whose cSMGs were not spared. The influence of the mean doses to the cSMG and parotid gland on the recovery of saliva output was equivalent to that of the mean V30 to the glands.

• OSTI ID: 22054509
• Journal Information: International Journal of Radiation Oncology, Biology and Physics, Journal Name: International Journal of Radiation Oncology, Biology and Physics Journal Issue: 5 Vol. 81; ISSN IOBPD3; ISSN 0360-3016
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
DOSIMETRY
HAZARDS
HEAD
NECK
NEOPLASMS
PATIENTS
RADIATION DOSES
RADIOTHERAPY
SALIVA
SALIVARY GLANDS