In response to concerns about raising the screening starting age from 18 to 25, researchers have reviewed the risks
As previously reported in the AJP, from December 2017 the biennial Pap test for women aged 18-69 will be changing to a five-yearly human papilloma virus (HPV) test commencing at age 25.
While primary prevention of cervical cancer is through the national HPV vaccination program, which began in 2007, there has been some concern that raising the screening starting age from 18 to 25 years may delay opportunistic detection of cervical cancers in young women.
In order to either confirm or allay fears, experienced researchers have reviewed all cases of invasive cervical cancer in Queensland woman under the age of 25 over the last 28 years.
A retrospective cohort study was undertaken at the Queensland Centre for Gynaecological Cancer and the Queensland Cancer Registry, of all women aged between 13 and 25 years diagnosed with cervical cancer in Queensland between 1984 and 2012.
The researchers found that there is a very low incidence of cervical cancer in women under 25 years of age, irrespective of the age of commencement of screening, or the screening interval – a result “consistent with the world literature”, they say.
A total of 56 women aged 13-25 were diagnosed with cervical cancer and treated between 1984 and 2012.
The commonest reason for the diagnosis of cancer was investigation of abnormal symptoms (39%), rather than routine Pap smear abnormalities (27%).
A further nineteen women (34%) were investigated for reasons that were not recorded or could not be found.
“The majority of younger women diagnosed with cervical cancer are symptomatic and this is particularly true for clinical cancers,” say the researchers.
“The symptomatic group would not be adversely affected by raising the age of onset of screening.
“Our study suggests that only a very small number of asymptomatic women might fail to benefit from detection of an early-stage cancer in a cytology-based screening program that commences at age 25 years in this era of HPV vaccination,” they say.
“This subgroup … may theoretically suffer as a consequence.”
However it is proposed that raising the starting age will improve efficiency and cost effectiveness without delaying diagnosis of or increasing morbidity or mortality associated with cervical cancer.
The researchers say that while they were unable to obtain complete details of some of the women in the study, “given the large numbers of women screened over this period, interpretation of results is unlikely to be affected.
“Our study has confirmed the very low incidence and mortality of cervical cancer in women under 25 years of age in Queensland.”
The National Cervical Screening Program, which commenced in 1991, has resulted in a very low incidence of cervical cancer across Australia – 7.4 new cases per 100,000 women.
Women aged 20-24 have the lowest incidence at 2 new cases per 100,000 women.