Although a wide spectrum of human papillomavirus is seen across the population of India, HPV-16 and HPV-18 are the most common types and a vaccination targeting these types could eliminate 75 per cent of the cervical cancers in the region, according to data presented at the American Association for Cancer Research Frontiers in Basic Cancer Research Meeting.
Cervical cancer caused by HPV is the most common cancer among Indian women, with an estimated 132,000 new cases and 74,000 deaths annually.”In terms of cancer death, India has one fourth of the global burden and when you standardise for age, it is the highest in the world,” said A Raj Kumar Patro, a doctoral student in the Department of Microbiology at the All India Institute of Medical Sciences, New Delhi. “Most women present with an advanced state of the disease and compliance with treatment is very poor,” he added.
To effectively vaccinate against HPV, scientists need a greater understanding of the genotype. More than 100 HPV genotypes have been identified in humans and at least 40 are found in the anogenital tract, which makes HPV a moving target. Patro and colleagues examined 106 women with invasive cervical cancer, 524 women with an unhealthy cervix and a community-based population of women who underwent HPV testing.
Among the women with invasive cervical cancer, 83 per cent were linked with HPV-16 or HPV-18. Of those who presented with an unhealthy cervix, 15.5 per cent had HPV. HPV-16 and HPV-18 were associated with 34.3 per cent of normal disease, 45.4 per cent of low-grade disease and 65.7 per cent of high grade disease. Overall HPV prevalence in the community cohort was seven per cent.
Patro said the HPV vaccine is generally well received in India, with none of the moral or religious objections like those seen in the United States. However, economics remains a significant barrier.
“The vaccine is better accepted than screening in most cases, but it is difficult for most of the population to purchase it at the current price,” said Patro. “At present it is purchased by the upper classes and if it becomes freely available through advocacy and outreach efforts, it could reach the general population.”