New vaccines being developed to battle viruses linked to cervical cancer may not benefit Chinese patients because they are more susceptible to a rarer strain of the virus.
The warning from a Chinese University medical research team is based on a three-year study of 1,924 patients with cancer and cervical diseases at Prince of Wales Hospital and Queen Elizabeth Hospital.
The team found that about one in five cervical cancer patients were infected by Human Papillomavirus Type 58, or HPV 58, a rare virus strain. Only two per cent of non-Chinese cancer patients overseas are afflicted by the virus.
In overseas countries, including North America and Europe, 98 per cent of cervical cancer cases were caused by HPV 16, which accounted for half of the cases in Hong Kong.
In Hong Kong, cervical cancer is the fourth most common cancer, with more than 400 new cases a year. It kills about 160 women a year.
Dr Paul Chan Kay-sheung, one of the leaders of the research team, estimated that 1.2 per cent of the adult female population, aged 18 and over, in Hong Kong are HPV 58 carriers.
The team has found that women carrying HPV 58 are 8.5 times more likely to develop cervical cancer than healthy women. The risk is 30 times more among HPV 16 carriers. In both strains it takes an average of five to 10 years for the cancer to develop.