3D conformal radiotherapy in primary nasopharyngeal cancer: effectiveness and prognostic factors

Abstract

Purpose: To assess the efficacy and safety of using 3D conformal radiation therapy (3DCRT) to treat nasopharyngeal cancer (NPC) in a Caucasian cohort and evaluate factors with prognostic value.

Methods: Between September 2001 and November 2012, 44 NPC patients with a mean age of 57 years underwent 3DCRT at the University Hospital of Ioannina. Nineteen patients (43%) presented with WHO type 1 and 2 histology. Thirty two patients (73%) had advanced-stage disease (stage III/IV). Thirty-one patients (70%) received chemotherapy. The mean total radiotherapy dose prescribed to the planning target volume (PTV) was 67.2 Gy. The daily dose was 1.8 Gy.

Results: With a median follow up of 43 months (range 8.4-125), the 4-year local relapse-free (LRFS), nodal relapse-free (NRFS), distant metastases-free survival (DMFS), disease-free survival (DFS) and overall survival (OS) were 90, 87, 91, 80 and 82%, respectively. Histology was a significant prognostic factor concerning overall survival, with worst prognosis in patients with WHO type 1/2 compared to type 3. Age <70 years, absence of retropharyngeal lymph node metastasis, complete response after treatment and the completion of ≥4 cycles of concurrent weekly cisplatin favored overall survival. Fifteen patients (34%) developed grade 3 late side effects (xerostomia: 6, soft tissue fibrosis: 6, hearing loss: 2, brachial plexus neuralgia: 1).

Conclusion: 3DCRT in our Caucasian cohort, characterized by predominantly advanced-stage disease, combined with chemotherapy, is an effective treatment modality approach in patients with NPC with excellent tolerance.