Effect of oral pilocarpine on xerostomia and quality of life in patients receiving curative radiotherapy for head and neck cancers

Abstract

6088 Background: Xerostomia is the most debilitating condition following irradiation (RT) in patients with head and neck cancers. The present study intended to evaluate the effect of salivary stimulants such as pilocarpine given concurrent with RT on xerostomia and quality of life in these patients. Methods: In a prospective study conducted between July 2004 and May 2006, 60 patients receiving curative (radical or postoperative) RT for squamous cell head and neck carcinoma were randomized into two groups; group A (n=30) received concurrent pilocarpine 5 mg thrice daily for 12 weeks starting on day 1 of RT while group B (n=30) did not receive pilocarpine. Xerostomia was assessed using RTOG/EORTC criteria, and Quality of life (QOL) using EORTC QLQ-C30 version 3.0 and QLQ-H&N35 questionnaires in phases I-V: preradiation, week 4 of RT, and at 1, 3 and 6 months following completion of RT. Results: Oral dryness was the commonest toxicity, its incidence in phase II being 80% in group A and 89% in group B. By phase V, 13% patients in group A and none in group B had recovered to their pretreatment status. When compared with group B, group A had a significantly lower incidence of oral dryness in phases III (p=0.001), IV (p=0.014) and V (p=0.009) and lesser speech difficulty in phase V (p=0.021). QOL evaluation showed a decline in functional scores and rise in symptom scores during radiation with subsequent improvement to pretreatment levels in phase V. Group A had a significantly higher physical functioning score than group B in phases III (p=0.037) and IV (p=0.027), a better emotional functioning score in phases III (p=0.046) and IV (p=0.008), and a higher global health score, especially in phases II (p=0.012) and III (p=0.001). QLQ-C30 symptom scores were comparable between the 2 groups while H&N35 symptom scores were higher in group B with higher painkiller use in phase II (p=0.043) and IV (p=0.011), and higher dryness (p=0.025), sticky saliva (p=0.021) and constipation (p=0.011) in phase IV. Conclusions: Concurrent pilocarpine during head and neck RT helps maintain salivary function, reduces xerostomia and improves the quality of life in these patients, both during and after RT, especially in terms of parameters related directly to xerostomia. No significant financial relationships to disclose.