Long term risk of invasive cancer after treatment for cervical intraepithelial neoplasia grade 3: population based cohort study

Abstract

Objective To study the long term risk of invasive cancer of the cervix or vagina after treatment for cervical intraepithelial neoplasia grade 3. Design Prospective cohort study. Setting Swedish cancer registry. Participants All women in Sweden with severe dysplasia or cervical carcinoma in situ (equivalent to cervical intraepithelial neoplasia grade 3) treated during 1958-2002 (n=132 493) contributing 2 315 724 woman years. Main outcome measures Standardised incidence ratios with risk of cancer in the Swedish general female population as reference, and relative risks in multivariable log-linear regression model, with internal references. Results Women with previous cervical intraepithelial neoplasia grade 3 had an increased risk of invasive cervical cancer compared with the general female population (standardised incidence ratio 2.34, 95% confidence interval 2.18 to 2.50). The increased risk showed a decreasing trend with time since diagnosis for women treated later than 1970 but the risk was still increased after 25 years. An effect of age was found, with an accentuated increase in risk for women aged more than 50. The excess risk for cervical cancer associated with previous cervical intraepithelial neoplasia grade 3 has steadily increased since 1958. For vaginal cancer the standardised incidence ratio was 6.82 (5.61 to 8.21) but this decreased to 2.65 after 25 years. Adjustments in the multivariable log-linear regression model did not substantially alter these results. Conclusions Women previously treated for cervical intraepithelial neoplasia grade 3 are at an increased risk of developing invasive cervical cancer and vaginal cancer. This risk has increased since the 1960s and is accentuated in women aged more than 50. The risk is still increased 25 years after treatment.

Long-Term Risk for Noncervical Anogenital Cancer in Women with Previously Diagnosed High-Grade Cervical Intraepithelial Neoplasia: A Danish Nationwide Cohort Study

“…In that study, the adjusted risks for anal, vulvar, and vaginal cancer were increased after 10 or more years of follow-up after a CIN3 diagnosis (10). A similar pattern is described in other studies (9,(12)(13)(14), but the results are not consistent (11).…”

“…Several studies have addressed the risk for anogenital cancers among women with CIN (9-14); however, in most, standardized incidence ratios were used to compare the risk for anogenital cancers in cohorts of women with cervical neoplasia with that of the general population (9,(11)(12)(13)(14). Such comparisons control for potential confounding by age and calendar time but do not take into account common risk factors such as socioeconomic status and smoking habits.…”

“…Still, there is relatively limited knowledge about the long-term risk for noncervical anogenital cancer in women with a previous diagnosis of CIN2 or CIN3. Some studies have shown that women with high-grade CIN have increased risks for anal, vulvar, and vaginal cancers (9)(10)(11)(12)(13)(14). Several of these studies, however, have limitations, such as small study populations, limited follow-up time, limited number of outcomes and, especially, lack of adjustment for potential confounders.…”

Risk of invasive cervical cancer in relation to clinical investigation and treatment after abnormal cytology: A population‐based case–control study

“…Another explanation would be that the volume removed with laser conisation in general is more than that removed with LLETZ, something that has been shown in a recent study by Phadnis et al 34 Also, the risk for invasive cervical cancer after treatment of CIN3 has increased in Sweden since the 1960s, and the risk for women treated in the 1990s has been found to be almost twice as high as for those treated in the 1960s. 35 This could be explained by changes in treatment modalities and the results give indirect support to our findings that more conservative methods increases the risk of invasive cervical cancer.…”

Clinical investigation of the safety and efficacy of a cervical intraepithelial neoplasia treatment using a hyperthermia device that uses heat induced by alternating magnetic fields

“…It is grouped into three categories: CIN I (mild dysplasia), CIN II (moderate to marked dysplasia) and CIN III (severe dysplasia to carcinoma in situ). Treating high-grade (HG)-CIN reduces the incidence and mortality caused by invasive cervical cancer in women with these lesions (1)(2)(3). Women treated for CIN are of reproductive age (mean age of approximately 30 years), although the disorder may also arise in much younger women (4,5).…”