For the broader O&G Magazine readership, balanced answers to those curly-yet-common questions in obstetrics and gynaecology.
‘When taking a history from a woman aged 22 years, she tells you that she has been sexually active since she was age 13. Is screening for cervical cancer appropriate?’
The short answer, probably quite unhelpful, is: no and possibly yes. Let me explain. With the introduction of the renewed National Cervical Screening Program (NCSP) in December 2017, the starting age for cervical screening using the new Cervical Screening Test (oncogenic HPV test with reflex liquid-based cytology) has been raised from 18 years to 25 years.1 So, in this case, the woman in question will not receive an invitation to screen for another three years. Is this appropriate and is it safe practice?
What is the evidence for the new starting age?
Women will not be invited to participate in the NCSP until they reach 25 years of age.2 In 2005, the International Agency for Research in Cancer (IARC) recommended cervical screening begin at the age of 25.3 Most countries with an organised approach to cervical screening commence screening at age 25 or 30 years, with cervical cancer incidence and mortality rates that are similar to Australia.4
The harms of screening younger women, mainly through overtreatment, far outweigh any perceived benefits, particularly in regard to reproductive outcomes in later life.5
Do young women develop cervical cancer?
Cervical cancer is rare in young women, but HPV infection is very common and usually resolves without intervention. Detection of HPV-related cervical abnormalities in younger women has led to unnecessary investigation and treatment in women who are very unlikely to develop cancer.6
Although women under 25 years of age have been screened in our current NCSP, this has had no impact on the incidence or mortality from cervical cancer in these women. A recent Australian study considered the effect of screening on the incidence of cervical cancer for different age cohorts between 1983 and 2010, and concluded that the starting age of 25 years is safe for Australian women.7 In addition, the authors noted that HPV vaccination will continue to cause a significant fall in the number of high-grade abnormalities in young women, making screening of younger women increasingly less effective.8
Why even consider screening this young woman?
In the absence of evidence that women who have experienced early sexual activity will benefit from screening under age 25 years, why even consider this approach?
Some health professionals and consumers (women) have expressed anecdotal concerns that women who have been exposed to HPV infection at a young age (13 years and younger) will not be screened until it is ‘too late’ to prevent the development of a cervical cancer. They consider these women will have had a longer time at risk, unscreened, and may develop cervical cancer before they are eligible to commence screening at age 25 years.
Are these women really at increased risk?
The 2016 Guidelines state: ‘There is a lack of currently available evidence to support screening women who have been exposed to early sexual activity.’9There is one study, which has provided indirect evidence from re-analysis of individual data from worldwide studies, showing that the relative risk for cervical cancer in women who first had sexual intercourse at age 14 years or younger was similar to the risk in women who had first intercourse at 16–18 years.10 11
In a recent national survey of Sexual Health in Australian Secondary Students, a significant proportion of women experience their first sexual intercourse at age 14–16 years, and the median age has increased in recent years to 16–17 years.12 It is far less common for women to have first intercourse at age 13 years and below, and this is more likely related to sexual abuse.13Many, but not all, of these women will have received HPV vaccination prior to sexual debut.
To screen or not to screen, that is the question
Routine cervical screening is not recommended in young women under age 25 years.114,15Women who have experienced early sexual activity or have been victims of sexual abuse are considered to be a ‘specific population’ and are considered separately in the new 2016 Guidelines.16 Because of the lack of currently available evidence for this ‘specific population’, the Guidelines have adopted a cautious individualised approach until further evidence is available.
Recommendation 15.2 states that: ‘For women who experienced first sexual activity at a young age (<14years) and who have not received HPV vaccine before sexual debut, a single HPV test between 20 and 24 years of age could be considered on an individual basis.’17
The emphasis here should be on the phrase ‘could be considered on an individual basis’, recognising that the evidence for such screening is non-existent at this time. Whether you offer to screen or not will depend on your interaction with the woman, her desires once you have discussed this with her and your personal experience and preference in such cases. You should note that the minimal benefits of cervical screening in young women should be weighed against the increased risk of harm that excisional procedures could have for future obstetric outcomes.18
What if she has symptoms?
Women at any age, who have symptoms suggestive of cervical cancer, should have a co-test (HPV and LBC) and be referred for appropriate investigation to exclude genital tract malignancy.19