~ Common Case of HPV
Posted by faisalrenzo on April 16, 2011
Human papillomavirus infection is a widespread condition that affects both men and women. ANNIE FREEDA CRUEZ talks to Dr Suresh Kumarasamy, a consultant obstetrician and gynaecologist, to find out more TALK on human papillomavirus (HPV) mostly centres on women since it increases their risk of cervical cancer.
But Dr Suresh Kumarasamy, a consultant obstetrician and gynaecologist, says the virus can infect men, too. “All types of HPV can be transmitted between men and women.
There’s also a rare form of non-sexual transmission from mother to child during delivery,” says Dr Suresh, who is also a gynaecological oncologist at Gleneagles Medical Centre in Penang.
In most cases, he adds, the transmission is done unknowingly because the infection is asymptomatic. Although there’s no data on the incidence or prevalence of HPV infection in the country, data from the WHO/ICO (Institut Catalia d’Oncologia) HPV Information Centre estimates that it’s about 6.2 per cent at any one time in the general female population.
Among women who have undergone pap smear, the prevalence of HPV infection is 8.4 per cent. But there’s data on the different HPV types in patients with cervical cancer in Malaysia. Among these patients, 73 per cent have evidence of HPV Type 16 and 65.2 per cent with HPV Type 18.
“Most men don’t know that they can be infected by HPV. The most deadly disease women can get from HPV infection is cervical cancer while men are at risk of other diseases as well as cancers,” says Dr Suresh, who is also an adjunct associate professor at Penang Medical College.
Although the vast majority of HPV cases show no symptoms, some may develop warts in their genital region. “Although easily treated, they can cause anxiety, embarrassment and long-term psychological, sexual and relationship problems,” says Dr Suresh.
Warts are generally asymptomatic. But they can sometimes cause symptoms, depending on their location. For example, warts in the vulva can cause pain during sexual intercourse, itchiness and a burning sensation while vaginal warts can cause discharge and bleeding.
Warts can also cause itchiness in the penis. Those that occur in the urethral meatus (opening of the urethra at the tip of the penis where urine is passed out) can cause blood in the urine or impairment of urinary stream.
Cancers are a different matter altogether. Female patients who have cancer of the cervix may experience bleeding after intercourse, irregular vaginal bleeding, bleeding after menopause or pelvic pain.
Dr Suresh says HPV can infect married couples and singles who are sexually active. “Prostitutes have a higher risk of infection.” In the United States, it is estimated that between 50 and 80 per cent of the adult population have had HPV at some point in their lives.
And although HPV infection is rare in virgins, it’s not impossible. The virus can spread from hand-to-genital, hand-to-anal and mouth-to-genital contact. Condoms may reduce the risk of infection, but they don’t completely eliminate it.
Although HPV infection is common, the majority of men and women clear the virus from the body and don’t suffer from any squealae of the infection, says Dr Suresh.
Only one per cent of men with HPV get warts while of a million women with HPV, only 1,600 get cancer if not screened. Dr Suresh says vaccination programmes should be aimed at as many people as possible and not only those at risk.
“The focus should be on effectiveness and safety, and not method of transmission.” Some types of HPV can infect the mouth and throat, called the aerodigestive tract.
HPV Types 6 and 11, the same types that cause genital warts in men and women, can also cause an uncommon but serious condition in infants and children called recurrent laryngeal papillamatosis.
“The virus is transmitted from mother to baby through the birth canal during delivery. The risk of infection in the child has been estimated to be one in 500 women,” says Dr Suresh. He adds that children with recurrent laryngeal papillamatosis can develop an obstruction of the respiratory tract, causing breathing difficulties. “They may require surgery to relieve the obstruction.
Some children need as many as 10 operations per year. One to three per cent of children with this condition die from it.” There is an extremely rare variation of this condition which occurs in adults which is thought to be transmitted by oral sex.
HPV infection is also implicated as the cause of a number of head and neck cancers. Dr Suresh says: “HPV infection is implicated in 36 per cent of cancers of the oropharynx and 24 per cent of mouth cancers. As far as oropharynx cancers are concerned, Types 16 and 18 account for 89 per cent of HPV infections.
In mouth cancers, 95 per cent of HPV infections are due to Types 16 and 18.” Two types of vaccine available locally can provide protection against HPV Types 16 and 18. The quadrivalent vaccine, or Gardasil, can also protect against HPV Types 6 and 11.
“Although no research has been done to see if these vaccines can protect against head and neck cancers or mouth cancers, their potential to prevent diseases caused by HPV infection is tremendous,” says Dr Suresh.
Currently, both vaccines are licensed by the US Food and Drug Administration for the protection against pre-cancer and cancer of the cervix.
The quadrivalent vaccine is also licensed against genital warts and pre-cancer of the vulva and vagina in women, and genital warts in men aged between nine and 26.
Genital warts: Found on shaft of penis (male), vagina, vulva, cervix (female) and around anus
Link to warts and cancers
THE human papillomavirus, or HPV, usually enters the skin through microscopic breaks in its surface that can happen, for example, during sexual intercourse.
It enters cells in the bottom most layer of the epithelium called basal cells. These cells are capable of dividing. HPV viral material (genome) replicates during division and moves up the layers of the epithelium as the cells mature. HPV infection stimulates cell growth, leading to irregularly thickened cell layers that become warts.
In the case of cancer, the virus integrates into the DNA of the host cell leading to over-expression of two proteins called E6 and E7. More changes take place and the cells become pre-cancerous, eventually resulting in cancer if undetected.
Dr Suresh Kumarasamy, who specialises in the treatment of gynaecological cancer and gynaecological surgery, has come across many patients with cancers of the female reproductive tract. “I see four or five new patients with gynaecological cancer each week.
But not all have cancers related to HPV. Ovarian cancer and uterine cancer are not related to HPV, but cervical cancer, vulva cancer and vaginal cancer are,” he says. “Uterine cancer can be diagnosed at an early stage, so can cervical cancer. But ovarian cancer is often diagnosed at a late stage.”
His youngest patient was 13 years old while the oldest was in her 90s. Dr Suresh says it is difficult to totally prevent HPV infection as the virus is widespread. “Vaccination is the most effective strategy and works best before one is infected with HPV.
Keeping a monogamous relationship can also lower the risk of HPV infection.” HPV infection can occur without penetrative sexual activity, too. “Transmission is possible through contact between the hands, genitals and anus as well as oral sex,” says Dr Suresh.
A study showed that using a condom all the time can reduce the risk of HPV infection by 70 per cent while using it 50 to 99 per cent of the time can only reduce the risk by 50 per cent. Dr Suresh says there’s a commercially available test for HPV for women.
“It is only indicated in the further evaluation of some types of low-grade abnormal pap smear as well as to determine the most appropriate interval for follow-up pap smears when an abnormal low-grade smear has been detected.” HPV testing is not carried out in males in a clinical setting, only in a research setting.
Men can be vaccinated too
GARDASIL, the quadrivalent vaccine, has been available in Malaysia since October 2006, four months after approval by the US Food and Drug Administration.
Malaysia is the second country in Asia, after Taiwan, to license the vaccine. “Men can be vaccinated against HPV. The US FDA recently approved vaccination for the prevention of genital warts in males between ages nine and 26,” says Dr Suresh Kumarasamy. But the manufacturer has to submit an application to the Drug Control Authority of Malaysia before the vaccination can be applied here, he adds.
Benefits of the vaccination include:
- It will decrease the risk of HPV infection and its sequelae (warts and cancer).
- If a large proportion of males are vaccinated, herd immunity will develop.
There will be less HPV infections, and the risk of women getting infected will also be reduced. Recent data from Australia has shown that the HPV vaccine is effective in reducing HPV-related cases in the community. This vaccine has been used in the Australian National Immunisation Programme since 2007.
There’s now less cases of genital warts in young women (25 per cent cut per quarter in 2008), with a smaller reduction in young heterosexual men (five per cent cut).
Source : http://www.nst.com.my