Nasopharynx Cancer

Nasopharynx Cancer Clinical Outcomes

Cancer of the Nasopharynx (NPC) is sixth most frequent cancer affecting Singaporean men occurring at an incidence of 10.8 per 100000 men per year. It is a cancer that affects younger Singaporeans with the majority affected between 40-65 years of age.

NPC is a highly curable malignancy that is generally managed using high dose radiation therapy (RT) or x-ray therapy, occasionally in combination with chemotherapy injections. The RT doses delivered to the head and neck region are high and the surrounding normal tissues such as salivary glands, temporal lobe and optic nerves are exposed to potential RT long-term side effects.

At the National University Cancer Institute, Singapore, the radiation therapy techniques that are used in patients are 3D conformal RT (3DCRT) and Intensity Modulated RT (IMRT). Both of these techniques utilise accurately placed multiple beams of radiation to hit the target and protect the surrounding normal tissues. Thus the radiation treatment technique that is required is very sophisticated and must be delivered carefully with close attention to high quality assurance.

Figure 1 : CT scan of patient with Nasopharynx Cancer (arrow); TCI@NUH radiation
therapy unit; and radiation plan for IMRT treatment

Local Control of NPC as a Radiation Oncology Clinical Quality Indicator

The most important immediate outcome of NPC treatment is control of the cancer at the initial primary site of the cancer at the back of the nose. In curative therapy the radiation therapy is principally directed to this site and the surrounding tissues and lymph nodes. For early stage NPC (stage I/II) RT is used as the only treatment, thus the success is dependent upon the accurate, quality delivery of radiation beams.

For this reason the local control of the NPC is used as a clinical quality indicator at TCI Radiation Oncology and our results are compared with international cancer units delivering sophisticated radiation treatment^1-3. Using these measures, local control of NPC approximates 90% on long-term follow-up³. These results are comparable to major centres locally and overseas ^4-6.

DefinitionConclusion

• Stage I/II NPC refers to patients who are diagnosed with a cancer in the nasopharynx that is localised to the postnasal space / extended into immediate surrounding tissues or with lymph node involvement limited to one side of the neck.
• Local control of the cancer refers to no relapse of cancer in the head and neck region and is defined at 3 years after diagnosis 

The local control for Stage I/II NPC is equivalent to major international centres and confirms quality delivery of radiation therapy at TCI@NUH. Further improvements to RT techniques, especially with increased use of IMRT, have been introduced at TCI@NUH to maximise local control and minimise side effects of RT.

Information is correct as at November 2009

Footnotes:

1. Thiagarajan A, Lin K, Tiong CE, Tan LK, Loh TK, Goh BC, Lu JJ. Sequential external beam radiotherapy and high-dose-rate intracavitary brachytherapy in T1 and T2 nasopharyngeal carcinoma: an evaluation of long-term outcome. Laryngoscope. 2006 Jun;116(6):938-43.
2. Lu JJ, Shakespeare TP, Thiagarajan A, Zhang X, Liang L, Tan S. Prospective phase II trial of concomitant boost radiotherapy for stage II nasopharyngeal carcinoma: an evaluation of response and toxicity. Laryngoscope. 2005 May;115(5):806-10.
3. Lu JJ, Kong L, Shakespeare TP, Loh KS, Zhang Q, Tan KS, Lee KM. Prospective phase II trial of concomitant boost radiotherapy for stage II nasopharyngeal carcinoma. Oral Oncol. 2008;44:703-9.
4. Lee N, Xia P, Quivey JM et al (UCSF San Francisco USA). Intensity-modulated radiotherapy in the treatment of nasopharyngeal carcinoma: an update of the UCSF experience. Int J Radiat Oncol Biol Phys. 2002 May 1;53(1):12-22.
5. Wolden SL, Chen WC, Pfister DG et al (MSKCC New York USA). Intensity-modulated radiation therapy (IMRT) for nasopharynx cancer: update of the Memorial Sloan-Kettering experience. Int J Radiat Oncol Biol Phys. 2006 Jan 1;64(1):57-62.
6. Tham IW, Hee SW, Yeo RM, Salleh PB, Lee J, Tan TW, Fong KW, Chua ET, Wee JT. Treatment of nasopharyngeal carcinoma using intensity-modulated radiotherapy-the national cancer centre singapore experience. Int J Radiat Oncol Biol Phys. 2009;75:1481-6.

This material does not cover all information and is not intended as a substitute for professional care. Please consult your physician on any matters regarding your health.