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Nasopharyngeal cancer (NPC) is one of the commonest cancers in Hong Kong and South China. The incidence of NPC is highest among people aged 40 to 60. The prognosis of this cancer is significantly dependent on the extent of disease at diagnosis. For patients with early-staged disease (i.e. stages I and II), localized radiotherapy alone can give a 5-year survival of over 85%. On the contrary, patients with more advanced disease require more extensive radiotherapy and systemic chemotherapy, and have worse prognosis. For example, the 5-year survival rate for stage IV patients is only 50%. Therefore, early detection is an important strategy in the management of NPC. The gold standard of diagnosing NPC is by endoscopic examination of the nasopharynx. However, limited by its invasive nature and availability, nasal endoscopy is not an ideal tool for screening NPC in asymptomatic subjects.

The development of NPC is closely linked with Epstein-Barr virus (EBV) infection. Making use of this association, the Department of Chemical Pathology at The Chinese University of Hong Kong (CUHK) established a blood test in 1999 for the detection of NPC based on the measurement of the genetic material of EBV (EBV DNA) in plasma. To date, the plasma EBV DNA analysis has been shown to be useful for the detection and monitoring of this cancer in patients presented with clinical symptoms. The test accuracy for NPC detection is over 95% and it is one of the most accurate blood-based tumor markers currently available.

With the generous support from Sir Michael and Lady Betty Kadoorie, CUHK is launching a community-based study to further investigate the effectiveness of this blood test for screening early NPC in asymptomatic individuals in end of July. In this study, 1,000 volunteers aged 40 to 60 with no clinical symptoms of NPC will be invited to enroll in a 2-year NPC screening program. During which, participants will be screened for NPC using the plasma EBV DNA test on 3 serial time points: at the time of enrolment, at 6 months and 18 months after the first test. Test-positive individuals will be referred to the Department of Otorhinolaryngology, Head and Neck Surgery of CUHK for further investigations, including an endoscopic examination of the nasopharynx, to confirm or exclude NPC. The objective of this study is to demonstrate that this blood test is useful for detecting early NPC in asymptomatic individuals, thereby improving their overall survival and minimizing treatment-associated side effects.

Twelve community visits at 6 residential areas in Shatin will be organized for educating the public about NPC and subject recruitment. One thousand Hong Kong citizens aged 40 to 60 who do not have a personal history of cancers or immune-related disorders and are not on immunosuppressants will be recruited in these community visits. The general public are welcome to attend the health talk which will be delivered in Cantonese. No prior reservation is needed for attending the health talk. After the talk, up to 100 subjects who fulfill the screening criteria of the NPC blood test will be selected by drawing lots in each community visit. Each subject will then be assigned a time slot from 1:30pm to 5:00pm for blood taking on that day.

Note: Quota of free NPC blood tests per visit is 100

1:00pm – 1:30pm Health Talk: Introduction to NPC Screening Program
1:30pm – 5:00pm Subject Recruitment and Blood Collection

Please refer to the website http://www.med.cuhk.edu.hk/v7/for the latest update about the NPC screening program.