3-D Intensity Modulated Radiotherapy (IMRT) in the Treatment of Nasopharyngeal Carcinoma: The UCSF Experience

James Metz, MD
OncoLink Associate Editor
Last Modified: November 1, 1999

Presenter: Khalil Sultanem, MD
Affiliation: University of California (San Francisco)

Summary:
Due to the proximity of critical normal tissues, carcinoma of the nasopharynx requires technically complex radiation treatment planning. The nasopharynx is an ideal location to evaluate IMRT for both tumor control and toxicity. This study was performed to evaluate the utilization of IMRT in the treatment of nasopharyngeal cancer.

Methods:

From 1995-1998 35 patients with nasopharyngeal cancer were treated with IMRT at UCSF.
Combined chemotherapy and radiation therapy was utilized in 91% of the patients.
19 patients had WHO Grade 3 disease
16 patients had WHO Grade 2 disease
Radiation therapy consisted of 70 Gy to the primary site and clinically positive nodal areas
Median follow-up for the patient population is 22 months

Results:

Local regional progression free survival is 100%
4 year actuarial distant metastatic progression free survival is 57%
Overall survival is 94%
Toxicity was relatively low with only one Grade 4 toxicity
Expected acute toxicity consisted of Grade 2/3 mucositis in a majority of patients
There were impressive results with minimal late toxicity as 50% of patients experienced only Grade I xerostomia
Half of patients experienced no subjective symptoms of xerostomia

Clinical/Scientific Implications:

This study reports improved target volume coverage with excellent local control of the primary site
The utiliztion of IMRT may provide significant sparing of salivary gland function
IMRT may improve overall outcome of patients treated for nasopharyngeal cancer
Further study of IMRT for the treatment of nasopharyngeal cancer is warranted, and longer follow-up is necessary to assess late toxicity

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