She was inconsolably distressed and started crying when the tissue biopsy report of her cervix showed that she had a high grade precancer. J, 30, a mother of two came from an island of a neighboring country. She complained of excessive yellowish vaginal discharge for the last few months. It was not smelly and was not associated with itchiness or soreness. She had regular Pap smears in her country and was told they were normal. However, no HPV test was done.
Vaginal examination revealed a small amount of yellowish discharge. The cervix appeared red and inflamed. Its surface bled slightly when it was swiped with a plastic brush to obtain cells for the pap smear. Pelvic examination and ultrasound scans of other pelvic organs were normal.
Pap smear showed some abnormal cells suggestive of precancer of the cervix. HPV test was positive for types 16 and 18 which are high-risk HPV strains.
She was advised to have a colposcopy examination with laser treatment. This was done by using a special telescope, called a colposcope, to examine abnormal areas in the cervix and a sample of tissue was collected for laboratory testing (biopsy).
What is High-risk HPV?
HPV is a group of more than 200 related viruses, some of which are spread through vaginal, anal, or oral sex. For the sexually transmitted HPVs, there are two groups: the low-risk and the high-risk strains.
Low-risk HPVs usually do not cause disease. But a few can cause warts on or around the genitals, anus, mouth, or throat.
High-risk HPVs can cause several types of cancer. There are about 14 high-risk HPV types including HPV 16 and 18. These two strains are responsible for 70 % of cervical cancer. (See also the article “Caught in Time: Cancer of Cervix” in the website)
How Common is High-risk HPV?
According to a local study of 2364 healthy women, one in four had been infected with high-risk HPV. The prevalence rate for women between 20 and 24 years old peaked at 49.1% but declined to 23% among women aged 30 to 49 years as most of the infections were cleared naturally. A small second peak of prevalence rate of 30% was observed among women above the age of 50 years old. This could be due to reinfection.
What Is The Natural Progression of High-risk HPV Infection?
HPV virus infects the cells of the cervix without much symptoms and approximately 90% of infections are cleared within two years by the immune system of the body. However, for some women, the infection lingers on and it is the persistent infection that causes cells to undergo precancerous changes.
Studies have shown that only 5% of high-risk HPV infections will progress to high grade precancer within three years. Of these lesions, 80 % will regress and the remainder will go on to invasive cancer within five years if no treatment is done.
J was more settled after I explained to her that her precancer had been treated and she did not have to have her uterus removed. She was still puzzled why previous pap smears could have missed her medical condition. I explained to her that the pap smear test was a screening test for abnormal cells on the cervix and the accuracy was only 60%. She was more reassured after that. On her review one year later, she remained well. She did not complain of vaginal discharge and the high-risk HPV strains were eventually cleared.