Purpose: Intensity-modulated radiation therapy (IMRT) enables radiation oncologists to optimally spare organs at risk while achieving homogeneous dose distribution in the target volume. Despite great advances in technology, xerostomia is one of the most detrimental long-term side effects after multimodal therapy in patients with locally advanced head and neck cancer (HNC). This prospective observational study examines the effect of parotid sparing on quality of life in long-term survivors.
Patients and methods: A total of 138 patients were grouped into unilateral (n = 75) and bilateral (n = 63) parotid sparing IMRT and questioned at 3, 24, and 60-month follow-up using the European Organization for Research and Treatment of Cancer QLQ-C30 and QLQ-H&N35 questionnaires. Treatment-related toxicity was scored according to the RTOG/EORTC toxicity criteria. Patients' QoL 24 and 60 months after IMRT was analyzed by ANCOVA using baseline QoL (3 months after IMRT) as a covariate.
Results: Patients with bilateral and unilateral parotid-sparing IMRT surviving 60 months experience similar acute and late side effects and similar changes in QoL. Three months after IMRT, physical and emotional function as well as fatigue, nausea and vomiting, pain, dyspnea, and financial problems are below (function scales) or above (symptom scales) the threshold of clinical importance. In both groups, symptom burden (EORTC H&N35) is high independent of parotid sparing 3 months after IMRT and decreases over time in a similar pattern. Pain and financial function remain burdensome throughout.
Conclusion: Long-term HNC survivors show a similar treatment-related toxicity profile independent of unilateral vs. bilateral parotid-sparing IMRT. Sparing one or both parotids had no effect on global QoL nor on the magnitude of changes in function and symptom scales over the observation period of 60 months. The financial impact of the disease and its detrimental effect on long-term QoL pose an additional risk to unmet needs in this special patient population. These results suggest that long-term survivors need and most likely will benefit from early medical intervention and support within survivorship programs.
Keywords: Acute ans late side effects; Long-term survivor; Multimodal therapy; Survivorship program; Xerostomia.