Feasibility of IMRT Modulation to Account for Scattered Radiation From Dental Fillings in Head and Neck Cancer

All patients will undergo a computed tomography (CT) simulation study +/- a positron emission tomography (PET) scan using ≤ 3mm slices for radiation treatment planning. A standard, "non-filling" optimized IMRT (Intensity Modulated Radiation Therapy) plan will be generated and patients will be treated with megavoltage radiation over a course of > 6 weeks with a planned tumor dose of > 60 Gy. A medical doctor will perform weekly mucositis evaluation and grading for the measured site once a week during radiation therapy

Modulation of an IMRT plan to reduce the dose to less than 35 Gy delivered to adjacent normal mucosa surrounding the dental filling without compromising normal tissue or tumor doses.

• IMRT

The time to onset of oral mucositis was measured from the start of radiation treatment until oral mucositis was visual observed by a clinician during the weekly checkup for the first time. Analysis done by Kaplan-Meier.

Adverse events were graded according to Common Terminology Criteria for Adverse Events (CTCAE) Version (V) 4.0. Medical doctor performed evaluation and grading of clinical and functional mucositis for the measured site weekly during the radiation treatment course and biweekly after completion of radiation until oral mucositis was < grade 2. A pain medication assessment was done for each mucositis time point. Patients completed the Oral Mucositis Weekly Questionnaire-Head and Neck cancer (OMWQ-HN) during and after treatment until oral mucositis is < grade 2.

The duration of grade 2 or higher oral mucositis was measured as the time from the first time oral mucositis was observed by a clinician at the weekly checkup until the oral mucositis was resolved.

The data was analyzed in a mixed effects model to account for the within subject correlation, since each patient contributed two measurements to the data set. The model was limited to those subjects who had experienced mucositis and then the outcome was the duration of grade 2 or higher mucositis. This allowed us to model the data in a mixed effects model with the continuous outcome of duration of grade 2 or higher mucositis.

The quality of life questionnaire was the HNC adaptation of the Oral Mucositis Daily Questionnaire (OMWQ). It is designed to assess the severity and impact of the oral mucositis by evaluating mouth and throat soreness and the degree to which the mouth and throat soreness interferes with activities of daily life such as eating, swallowing, drinking, talking and sleeping.

This outcome measures soreness in both the mouth and throat.

This outcome is not a combination of several sub-scales. This outcome was the response to the single question: "On a scale from 0 to 10, how would you rate your OVERALL MOUTH AND THROAT SORENESS during the past 24 hours?"

Mouth and throat soreness was measured as a single scale from 0 (no soreness) to 10 (worst soreness possible).

The quality of life questionnaire was the HNC adaptation of the Oral Mucositis Daily Questionnaire (OMDQ). It is designed to assess the severity and impact of the oral mucositis by evaluating mouth and throat soreness and the degree to which the mouth and throat soreness interferes with activities of daily life such as eating, swallowing, drinking, talking and sleeping.

This outcome measures pain in the mouth only.

This outcome is not a combination of several sub-scales. This outcome was the response to a single question: "On a scale from 0 to 10, what number best describes the MOUTH PAIN that you experienced in the past 24 hours?"

Mouth pain scale was measured as a single scale from 0 (no pain) to 10 (worst pain imaginable).