This week saw yet another tragic case of a 29-year-old woman who has died of cervix cancer leaving a baby daughter and six years old child. It seems as though she had presented with many episodes of post-coital bleeding which seem to have been ignored by clinicians looking after her. It was only when she went into labour at 26 weeks and at 2 cm dilation that it was noticed that she had a clinically recognisable cervical cancer (probably a stage 2/3). It is yet another example of failing to recognise the most basic symptoms and signs of invasive cervical cancer. Clinicians persistently ignore the guidelines produced by NICE and the NHS cervical screening program (second edition 2010) which specifically states that women with post-coital bleeding should be referred urgently for colposcopy or to a gynaecologist experienced in cervical disease.
This woman was in her late 20s when cervical cancer was diagnosed and yet we know the disease could have been picked up easily in its advanced pre-cancerous stages with a cervical smear from the age of 25. Even if she had had very early stage disease (superficially invasive/micro invasive carcinoma) she would have been eminently curable.
Audits of women who have been in this position show that cervical cytology can miss the diagnosis even in those with high-grade disease. Thankfully, HPV screening, which is a much more accurate test and which will be introduced in the near future will hopefully diagnose most of these women at an earlier stage.
It was interesting at the recent meeting of the BSCCP (British Society for Colposcopy and Cervical Pathology) meeting in Nottingham to listen to a number of presentations relating to pre-cancer in pregnancy. The presentation by Dr Faiza Gaba and colleagues from Aberdeen noted that the rush to perform more conservative cervical excisions for CIN, so as to avoid an increase in premature labour in subsequent pregnancy, has not surprisingly led to the discovery of a significant residual high-grade CIN because of incomplete excision. Dr Gaba ended the presentation by saying “it appears we are being cautious in over excising high-grade CIN to prevent pre-term labour whilst leaving behind persistent disease.”
In another presentation from Guys and St Thomas’s hospital in London, Dr Gulnaz Majeed noted that 20% of women having mid-trimester miscarriages and 21% of pre-term labour women have an associated cervical abnormality (Low SIL/High SIL). We have known for a number of years that women with CIN having increased risk of pre-term labour and the argument has been that there is an inherent problem in the cervix related to possible lifestyle changes such as smoking, alcohol and malnutrition that lead to problems in the collagen and fibrous tissue of the cervix. It is these lifestyle changes that also put the woman at risk for CIN.
It seems from these observations that the simple removal of a large amount of cervical tissue during and excisional procedure may not be the primary cause of this increase in pre-term labour. It may indeed be in relation to lifestyle changes as mentioned above. However, another paper at the meeting from Maria Kyrgiou’s team (presented by Anita Mitra) who have been studying this problem for a number of years, looked specifically at the presence of certain vaginal organisms (Lactobacillus) which play an important role in the prevention of urogenital disease and infections and are called the vaginal microbiome system. They showed that “women with CIN have a more diverse Lactobacillus-depleted vaginal microbiome system, compared to normal women”. They suggest this indicates that an abnormal microbiome may be involved in HPV persistence and may play a role in carcinogenesis. Obviously more work needs to be done in this field.
The answer to this problem of increased preterm labour in these women is not a simple one of just the removal of a large amount of cervical tissue when CIN is treated.