A Phase III Study Of Concomitant Oral Pilocarpine To Reduce Hypo-Salivation And Mucositis Assocated With Curative Radiation Therapy (RT) In Head And Neck (H&N) Cancer Patients. RTOG 9709
Diana Stripp, MD
University of Pennsylvania Cancer
Last Modified: May 13, 2001
Presenter: Charles W. Scarantino/Charles B. Scott
- Radiotherapy plays a major role in the management of H&N cancer.
- The major treatment side effects are mucositis and xerostomia (dry mouth), which can affect tolerance and result in treatment interuptions.
- For patients recieving > 50Gy of radiation, xerostomia is largely permanent and can greatly impact the quality of life (QOL).
- Pilocarpine (P) acts to stimulate salivary glands and is approved for post radiation xerostomia.
- Therefore, whether the concomitant use of P is able to preserve salivary flow in H&N cancer patients receiving curative RT is the subject of this study.
Materials and Methods:
- To be eligible, patients were required to have 50% of the volume of the major salivary glands planned to receive 50Gy of radiation
- Patients provided stimulated and unstimulated samples of saliva (measured in ml/min) prior to, 3mo and 6mo after initiation of RT and complete the Univ. of Washington H&N QOL forms.
- Patients were randomized to receive P at 5mg qid or placebo.
- 249 patients were registered, 244 were eligible for analysis.
- Patients were evenly distributed by demographic factors. There was a slightly higher performance status in the group of patients receiving P
- At 3mo following the initiation of RT, the average reduction in unstimulated salivary flow was not significantly different between both arms.
- At 6 mo., statistically significant (p=0.049) preservation of salivary function was observed in the P group (-1.0ml/5min) whereas continued functional loss was observed in the placebo arm (-2.0ml/5min).
- At 6mo grade 2 or worse salivary gland toxicity was 30% on P and 38% on placebo.
- There was no difference between groups on mucositis or in QOL value at 3mo (75% vs. 66%, p=0.27).
- Evaluation of mucositis showed no difference in the 2 arms. Sweating was the most frequent toxicity.
- Concomitant use of oral pilocarpine improves salivary flow and decreases radiation-associated xerostomia.
- However, no effects were observed on radiation-associated mucositis.
Decreasing radiation-associated xerostomia will greatly impact on the side effect related to the head and neck radiation treatment. Oral pilocarpine is reasonable to consider in patients receiving head and neck irradiation that includes a significant portion of the salivary glands.