Impact on Xerostomia for Nasopharyngeal Carcinoma Patients Treated With or Without Superficial Parotid Lobe-sparing Intensity-modulated Radiotherapy

Study Overview
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Brief Summary
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This is a prospective phase II clinical randomized controlled study, the purpose of this study is to assess whether superficial parotid lobe-sparing intensity-modulated radiotherapy (SPLS-IMRT) can decrease the incidence of xerostomia versus conventional IMRT (C-IMRT) in NPC patients.

Official Title
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Impact on Xerostomia for Nasopharyngeal Carcinoma Patients Treated With or Without Superficial Parotid Lobe-sparing Intensity-modulated Radiotherapy: a Prospective Phase II Clinical Randomized Controlled Study

Conditions
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Nasopharyngeal Carcinoma, Radiation-induced Xerostomia

Intervention / Treatment
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* Radiation: superficial parotid lobe-sparing intensity-modulated radiotherapy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria:1) newly diagnosed, histologically confirmed World Health Organization (WHO) type II-III NPC; 2) stage I-IVa (T1-4 N0-3M0) according to the staging system of the 8th American Joint Committee on Cancer/Union for International Cancer Control (AJCC/UICC); 3) no prior antitumor therapy; 4) no tumor involvement in salivary gland; 5) no parotid glands disorder and no history of parotid glands surgery; 6) ages between 18 and 70 years; 7) Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 1, and 8) adequate organ function Exclusion Criteria: 1) used salivary stimulating or protecting agent; 2) metachronous or synchronous malignancy; 3) pregnancy or lactation; or 4) severe comorbidities. The pretreatment evaluation included a complete history and physical examination, nasopharyngoscopy, chest X-ray, complete blood count, liver and renal biochemistry, and magnetic resonance imaging (MRI) of the head and neck.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: SPLS-IMRT<br>The superficial parotid lobe was contoured as an OAR, and V26 (the percentage volume receiving 26 Gy or more) in the superficial parotid lobe was constrained to be less than 30% | Radiation: superficial parotid lobe-sparing intensity-modulated radiotherapy<br>* The superficial parotid lobe was contoured as an OAR, and V26 (the percentage volume receiving 26 Gy or more) in the superficial parotid lobe was constrained to be less than 30%.<br>|
| No Intervention: C-IMRT<br>The entire parotid gland was delineated as an OAR, and V36 (the percentage volume receiving 36 Gy or more) in the entire parotid gland was constrained to be less than 40% | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the incidence of xerostomia | the incidence of xerostomia at 12m post-RT based on Radiation Therapy Oncology Group (RTOG) criteria | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| xerostomia questionnaire score | The XQ consisted of 8 specific questions which were listed as follows: difficulty in talking; difficulty in chewing; difficulty in swallowing solid food; frequency of sleeping problems; mouth and throat dryness when eating food; mouth and throat dryness while not eating; frequency of sipping liquids to aid swallowing food; frequency of sipping liquids for oral comfort when not eating. | 12 months | 
| Salivary flow rate | unstimulated salivary flow rateand stimulated salivary flow rate | 12 months | 
| locoregional relapse-free survival |  | 36 months | 
| distant metastasis-free survival |  | 36 months | 
| overall survival |  | 36 months |