Authors: Hollie Franklin, Future Science Group
In a study recently published online in the International Journal of Cancer, researchers from the Brigham and Women’s Hospital (MA, USA) describe a novel approach for preventing cervical cancer. This approach is based on findings showing a reduction in the risk of cervical cancer after the removal of a discrete population of squamocolumnar junction (SCJ) cells from the cervix. SCJ cells reside in the cervical canal and have been suggested to be the origin of cervical cancer.
A research team, co-led by Christopher Crum of Brigham and Women’s Hospital, based their study on recent findings that identified SCJ cells as a putative cell of origin for cervical intraepithelial neoplasia (CIN) and cervical cancer. It has been suggested that these cells may not regenerate following excision via a loop electrosurgical excision procedure.
Crum and colleagues addressed the impact of SCJ cell excision on the temporal dynamics, histologic and viral (human papillomavirus) characteristics of recurrent CIN. In their study, 131 women with CIN underwent loop electrosurgery excision to remove SCJ cells. Throughout the follow-up period, which was up to 4 years, 16 (12.2%) recurrences were observed. Four (25%) were observed at the first follow-up visit and were suggestive of nonexcised residual disease. Twelve patients (75%) manifested after the first visit and were all ectocervix or in mature metaplastic epithelium. All 12 instances were cervical intraepithelial neoplasias and did not have any SCJ cells.
This markedly lower risk of CIN grade 2/3 after successful SCJ excision suggests that the removal of the SCJ cells could be a critical variable in reducing the risk of subsequent CIN grade 2/3 and cervical cancer.
Crum stated “We have always suspected that most recurrences following apparently successful therapy do not develop in the same location as the original precancer, which was at the SCJ.”
He continued: “Moreover, studies in the literature have shown that the risk of a significant precancer following successful removal is quite low. Our study is in sync with these observations and suggests that removing SCJ cells might have a significant impact in reducing the risk of cervical cancer.”
Crum has also reiterated that eliminating SCJ cells does not prevent CIN nor prevent human papilloma virus infection, which can lead to cervical cancer. However, the researchers state that what is significant about the findings is that removal of SCJ cells seems to alter recurrence patterns, probably because the cell population that is most susceptible to the development of more dangerous precancers is removed.
Crum went on to say, “This is a concept that is in great need of a controlled clinical trial aimed at prevention rather than treatment. It would give us important insights into whether pre-emptive removal of the SCJ region would have the desired effect.”
An accompanying editorial has also been published by Silvia Franceschi, International Agency for Research on Cancer (Lyon, France), and suggests continuation of the work by “careful evaluation of the impact of prophylactic ablation in the framework of large screening programmes.”
Source: Herfs M, Somja J, Howitt BE et al. Unique recurrence patterns of cervical intraepithelial neoplasia after excision of the squamocolumnar junction. Int. J. Cancer doi: 10.1002/ijc.28978 (2014) [Epub ahead of print]; Brigham and Women’s Hospital press release