Late toxicities after conventional radiation therapy alone for nasopharyngeal carcinoma

Abstract 

Background and purpose

We sought to evaluate the nature and frequency of late toxicities in a cohort of nasopharyngeal cancer (NPC) patients treated with conventional radiotherapy alone.

Methods and materials

Seven-hundred and ninety-six consecutive NPC patients treated using conventional radiotherapy at a single center from 1992 to 1995 were retrospectively analyzed. Patients with histology proven, completely staged, Stage I–IVB World Health Organization Type I–III NPC and completed radical radiotherapy were included. Patients with incomplete staging investigations, distant metastases at diagnosis, previous treatment, and incomplete radiotherapy were excluded. Radiotherapy-related complications were categorized using the RTOG Late Radiation Morbidity Scoring Criteria.

Results

Median follow-up was 7.2years. The 5-year overall survival and disease free survival were 69% and 56%, respectively, and the corresponding 10-year rates were 52% and 44%. Among 771 patients with at least 3months of follow-up post treatment, 565 (73%) developed RT-related complications. Diagnosed neurological complications were cranial nerve palsies (n=70; 9%), temporal lobe necrosis (n=37; 5%), Lhermitte’s syndrome (n=7; 1%), and brachial plexopathy (n=2; 0.3%). Non-neurological complications included xerostomia (n=353; 46%), neck fibrosis (n=169; 22%), hypo-pituitarism (n=48; 6%), hearing loss (n=120; 16%), dysphagia (n=116; 15%), otorrhea (n=101; 13%), tinnitus (n=94; 12%), permanent tube feeding (n=61; 8%), trismus (n=45; 6%), second malignancies within treatment field (n=17; 2%), and osteo-radionecrosis (n=13; 2%).

Conclusions

While radiotherapy is curative in NPC, many patients suffer significant late treatment morbidities with conventional radiotherapy techniques.

Keywords: Nasopharyngeal cancer, Conventional radiation, Late treatment toxicity, Cranial nerve palsies, Quality of life