The Pill, HPV And Cancer

[Guest guest]

The Pill, HPV And Cancer LONDON, March 26, 2002 -

http://www.cbsnews.com/stories/2002/03/26/health/main504688.shtml -

 

Long-term use of the birth control pill can quadruple the risk of cervical

cancer in women infected with the sexually transmitted human papilloma virus

(HPV), scientists said Tuesday.

 

Experts say the study supports what many gynecologists have long suspected -

that there is a causal connection between the pills and cervical cancer.

 

Previous studies have not ruled out the possibility women who take the pill

may simply be more likely to be infected with human papilloma virus, the

main cause of the cancer.

 

" This study suggests that if you've got an HPV infection, oral

contraceptives may actually be promoting the rate at which that progresses

to cancer, " said Dr. Jack Cuzick, head of mathematics, statistics and

epidemiology at Cancer Research UK in London. He was not connected with the

study.

 

Nearly all sexually active women will be infected by HPV sometime during

their lives, but in most cases the immune system quickly eliminates it.

 

The key issue is why, in some cases, the virus does not go away. If the

infection persists, the chances of cancer increase enormously.

 

The study was conducted by the International Agency for Research on Cancer,

an arm of the World Health Organization.

 

Researchers pooled data from eight earlier studies of 3,769 women from four

continents. Of those, 1,853 had cervical cancer, and 1,916 did not.

 

As expected, nearly all the women with cancer tested positive for HPV, while

hardly any who were cancer-free had the virus.

 

The WHO researchers found that women who had taken the pill were no more

likely than the others to be carriers of HPV.

 

However, those infected with HPV who had used birth control pills for an

accumulated total of five years or more were nearly three times more likely

to develop cervical cancer than HPV-infected women who had never taken the

pill.

 

The increased risk persisted for up to 14 years after stopping the

contraceptives.

 

Women who had taken the pill for 10 years or more were four times more

likely to get the disease than those who had never taken it.

 

Using the pill for less than five years did not result in a higher chance of

cervical cancer.

 

" We think that our results lend support to the existence of an association

between oral contraceptives and HPV, " said scientist Silvia Franceschi.

 

" They could help women who have persistent HPV infection to balance the

benefits and harms of long-term oral contraceptive use, and suggest that

long-term users of oral contraceptives should be included in cervical

screening programs, " she added.

 

Cuzick said the findings should be interpreted cautiously because the women

were only tested for the virus once.

 

" Ideally, they should be positive on two occasions, at least six months

apart, before you call them positive, " he said.

 

The research was to be published Wednesday on the Web site of The Lancet

medical journal.

 

Women have about a 1 percent chance of developing cervical cancer. Based on

the new findings, taking the pill for five years or more could push that

chance up to about 3 percent and taking it for a total of 10 years could

raise it to about 4 percent.

 

Worldwide, almost 360,000 women were diagnosed with cervical cancer in 1990,

the latest date for which figures are available. Of those, 190,000 died of

the disease. It is the second most common cancer in women.

 

Cervical cancer strikes 12,900 American women each year and kills 4,400 of

them.

 

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published, broadcast, rewritten, or redistributed. The Associated Press and

Reuters Limited contributed to this report.