Cervical carcinoma in situ and use of depot-medroxyprogesterone acetate (DMPA). WHO Collaborative Study of Neoplasia and Steroid Contraceptives

Functional roles of female sex hormones and their nuclear receptors in cervical cancer

There has been little progress for several decades in modalities to treat cervical cancer. While the cervix is a hormone-sensitive tissue, physiologic roles of estrogen receptor α (ERα), progesterone receptor (PR), and their ligands in this tissue are poorly understood. It has hampered critical assessments of data in early epidemiologic and clinical studies for cervical cancer. Experimental evidence obtained from studies using mouse models has provided new insights into the molecular mechanism of ERα and PR in cervical cancer. In a mouse model expressing human papillomavirus (HPV) oncogenes, exogenous estrogen promotes cervical cancer through stromal ERα. In the same mouse model, genetic ablation of PR promotes cervical carcinogenesis without exogenous estrogen. Medroxyprogesterone acetate, a PR-activating drug, regresses cervical cancer in the mouse model. These results support that ERα and PR play opposite roles in cervical cancer. They further support that ERα inhibition and PR activation may be translated into valuable treatment for a subset of cervical cancers.

Canadian Contraception Consensus (Part 3 of 4): Chapter 8 - Progestin-Only Contraception

OBJECTIVE

To provide guidelines for health care providers on the use of contraceptive methods to prevent pregnancy and on the promotion of healthy sexuality.

OUTCOMES

Overall efficacy of cited contraceptive methods, assessing reduction in pregnancy rate, safety, ease of use, and side effects; the effect of cited contraceptive methods on sexual health and general well-being; and the relative cost and availability of cited contraceptive methods in Canada.

EVIDENCE

Published literature was retrieved through searches of Medline and The Cochrane Database from January 1994 to January 2015 using appropriate controlled vocabulary (e.g., contraception, sexuality, sexual health) and key words (e.g., contraception, family planning, hormonal contraception, emergency contraception). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies published in English from January 1994 to January 2015. Searches were updated on a regular basis in incorporated in the guideline to June 2015. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies.

VALUES

The quality of the evidence in this document was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care (Table 1). CHAPTER 8: PROGESTIN-ONLY CONTRACEPTION: Summary Statements Recommendations.

Role of nuclear progesterone receptor isoforms in uterine pathophysiology

BACKGROUND

Progesterone is a key hormonal regulator of the female reproductive system. It plays a major role to prepare the uterus for implantation and in the establishment and maintenance of pregnancy. Actions of progesterone on the uterine tissues (endometrium, myometrium and cervix) are mediated by the combined effects of two progesterone receptor (PR) isoforms, designated PR-A and PR-B. Both receptors function primarily as ligand-activated transcription factors. Progesterone action on the uterine tissues is qualitatively and quantitatively determined by the relative levels and transcriptional activities of PR-A and PR-B. The transcriptional activity of the PR isoforms is affected by specific transcriptional coregulators and by PR post-translational modifications that affect gene promoter targeting. In this context, appropriate temporal and cell-specific expression and function of PR-A and PR-B are critical for normal uterine function.

METHODS

Relevant studies describing the role of PRs in uterine physiology and pathology (endometriosis, uterine leiomyoma, endometrial cancer, cervical cancer and recurrent pregnancy loss) were comprehensively searched using PubMed, Cochrane Library, Web of Science, and Google Scholar and critically reviewed.

RESULTS

Progesterone, acting through PR-A and PR-B, regulates the development and function of the endometrium and induces changes in cells essential for implantation and the establishment and maintenance of pregnancy. During pregnancy, progesterone via the PRs promotes myometrial relaxation and cervical closure. Withdrawal of PR-mediated progesterone signaling triggers menstruation and parturition. PR-mediated progesterone signaling is anti-mitogenic in endometrial epithelial cells, and as such, mitigates the tropic effects of estrogen on eutopic normal endometrium, and on ectopic implants in endometriosis. Similarly, ligand-activated PRs function as tumor suppressors in endometrial cancer cells through inhibition of key cellular signaling pathways required for growth. In contrast, progesterone via PR activation appears to increase leiomyoma growth. The exact role of PRs in cervical cancer is unclear. PRs regulate implantation and therefore aberrant PR function may be implicated in recurrent pregnancy loss (RPL). PRs likely regulate key immunogenic factors involved in RPL. However, the exact role of PRs in the pathophysiology of RPL and the use of progesterone for therapeutic benefit remains uncertain.

CONCLUSIONS

PRs are key mediators of progesterone action in uterine tissues and are essential for normal uterine function. Aberrant PR function (due to abnormal expression and/or function) is a major cause of uterine pathophysiology. Further investigation of the underlying mechanisms of PR isoform action in the uterus is required, as this knowledge will afford the opportunity to create progestin/PR-based therapeutics to treat various uterine pathologies.

Progesterone signaling inhibits cervical carcinogenesis in mice

Human papillomavirus is the main cause of cervical cancer, yet other nonviral cofactors are also required for the disease. The uterine cervix is a hormone-responsive tissue, and female hormones have been implicated in cervical carcinogenesis. A transgenic mouse model expressing human papillomavirus oncogenes E6 and/or E7 has proven useful to study a mechanism of hormone actions in the context of this common malignancy. Estrogen and estrogen receptor α are required for the development of cervical cancer in this mouse model. Estrogen receptor α is known to up-regulate expression of the progesterone receptor, which, on activation by its ligands, either promotes or inhibits carcinogenesis, depending on the tissue context. Here, we report that progesterone receptor inhibits cervical and vaginal epithelial cell proliferation in a ligand-dependent manner. We also report that synthetic progestin medroxyprogesterone acetate promotes regression of cancers and precancerous lesions in the female lower reproductive tracts (ie, cervix and vagina) in the human papillomavirus transgenic mouse model. Our results provide the first experimental evidence that supports the hypothesis that progesterone signaling is inhibitory for cervical carcinogenesis in vivo.

Loop Electrosurgical Excisional Procedure (LEEP) Done for Discrepancy: Does the Time from HGSIL Affect Pathologic Grade of CIN in LEEP Specimen?

Objective. When pathologic discrepancy arises between high-grade cytology on Papanicolaou (Pap) smear and low-grade histology on cervical biopsy, Loop Electrosurgical Excisional Procedure (LEEP) is one management alternative. Our objective was to determine whether the time from initial HGSIL Pap to LEEP affects the pathologic grade of the LEEP specimen. Study Design. We performed a retrospective case-control study identifying LEEPs performed for discrepancy over a 10-year period (1997-2007). 121 subjects were separated into two groups based on LEEP pathology (</=CIN 1 and CIN 2,3) and compared using chi(2). Results. Of the 121 LEEP specimens, 67 (55.4%) had CIN 2,3. CIN 2,3 was more often discovered when LEEP was performed within 3 months of the HGSIL Pap smear versus after 5 months (55.2% versus 16.4%, P = .096). Conclusion. Women undergoing LEEP for discrepancy >5 months from their HGSIL Pap demonstrated a trend toward less CIN 2,3 on LEEP pathology.

Systematic literature reviews and meta-analyses: part 6 of a series on evaluation of scientific publications

BACKGROUND

Because of the rising number of scientific publications, it is important to have a means of jointly summarizing and assessing different studies on a single topic. Systematic literature reviews, meta-analyses of published data, and meta-analyses of individual data (pooled reanalyses) are now being published with increasing frequency. We here describe the essential features of these methods and discuss their strengths and weaknesses.

METHODS

This article is based on a selective literature search. The different types of review and meta-analysis are described, the methods used in each are outlined so that they can be evaluated, and a checklist is given for the assessment of reviews and meta-analyses of scientific articles.

RESULTS

Systematic literature reviews provide an overview of the state of research on a given topic and enable an assessment of the quality of individual studies. They also allow the results of different studies to be evaluated together when these are inconsistent. Meta-analyses additionally allow calculation of pooled estimates of an effect. The different types of review and meta-analysis are discussed with examples from the literature on one particular topic.

CONCLUSIONS

Systematic literature reviews and meta-analyses enable the research findings and treatment effects obtained in different individual studies to be summed up and evaluated.

Cervical cancer and hormonal contraceptives: collaborative reanalysis of individual data for 16,573 women with cervical cancer and 35,509 women without cervical cancer from 24 epidemiological studies

BACKGROUND

Combined oral contraceptives are classified by the International Agency for Research on Cancer as a cause of cervical cancer. As the incidence of cervical cancer increases with age, the public-health implications of this association depend largely on the persistence of effects long after use of oral contraceptives has ceased. Information from 24 studies worldwide is pooled here to investigate the association between cervical carcinoma and pattern of oral contraceptive use.

METHODS

Individual data for 16,573 women with cervical cancer and 35,509 without cervical cancer were reanalysed centrally. Relative risks of cervical cancer were estimated by conditional logistic regression, stratifying by study, age, number of sexual partners, age at first intercourse, parity, smoking, and screening.

FINDINGS

Among current users of oral contraceptives the risk of invasive cervical cancer increased with increasing duration of use (relative risk for 5 or more years' use versus never use, 1.90 [95% CI 1.69-2.13]). The risk declined after use ceased, and by 10 or more years had returned to that of never users. A similar pattern of risk was seen both for invasive and in-situ cancer, and in women who tested positive for high-risk human papillomavirus. Relative risk did not vary substantially between women with different characteristics.

INTERPRETATION

The relative risk of cervical cancer is increased in current users of oral contraceptives and declines after use ceases. 10 years' use of oral contraceptives from around age 20 to 30 years is estimated to increase the cumulative incidence of invasive cervical cancer by age 50 from 7.3 to 8.3 per 1000 in less developed countries and from 3.8 to 4.5 per 1000 in more developed countries.

Cervical cancer and use of hormonal contraceptives: a systematic review

BACKGROUND

Human papillomavirus (HPV) is believed to be the most important cause of cervical cancer. Recent studies suggest that long duration use of oral contraceptives increases the risk of cervical cancer in HPV positive women.

METHODS

Results from published studies were combined to examine the relationship between invasive and in situ cervical cancer and duration and recency of use of hormonal contraceptives, with particular attention to HPV infection.

FINDINGS

28 eligible studies were identified, together including 12531 women with cervical cancer. Compared with never users of oral contraceptives, the relative risks of cervical cancer increased with increasing duration of use: for durations of approximately less than 5 years, 5-9 years, and 10 or more years, respectively, the summary relative risks were 1.1 (95% CI 1.1-1.2), 1.6 (1.4-1.7), and 2.2 (1.9-2.4) for all women; and 0.9 (0.7-1.2), 1.3 (1.0-1.9), and 2.5 (1.6-3.9) for HPV positive women. The results were broadly similar for invasive and in situ cervical cancers, for squamous cell and adenocarcinoma, and in studies that adjusted for HPV status, number of sexual partners, cervical screening, smoking, or use of barrier contraceptives. The limited available data suggest that the relative risk of cervical cancer may decrease after use of oral contraceptives ceases. However, study designs varied and there was some heterogeneity between study results.

INTERPRETATION

Although long duration use of hormonal contraceptives is associated with an increased risk of cervical cancer, the public health implications of these findings depend largely on the extent to which the observed associations remain long after use of hormonal contraceptives has ceased, and this cannot be evaluated properly from published data.

Hormonal effects of Depo-Provera in cervical smears: a comparison with Triphasil and postmenopausal effects

BACKGROUND

Long-acting injectable contraceptive agents may cause changes in cervical smears that could impair the detection of epithelial abnormalities. The objectives of the current study were to 1) compare the hormonal effects of depot-medroxyprogesterone acetate (Depo-Provera) (DP) in cervical smears with those of levonorgestrel and ethinyl estradiol (Triphasil) (TP) and postmenopausal (PM) changes; and 2) determine whether the duration of DP use affects squamous maturation.

METHODS

Satisfactory cervical smears from 50 DP users, 55 TP users, and 51 PM patients were evaluated blindly for: 1) squamous cell curling, crowding, cytolysis, and navicular cell formation; 2) pseudoparakeratosis, blue blobs, and histiocytes; 3) endometrial cells and blood; 4) single or enlarged endocervical nuclei and mucin-depleted endocervical cells; 5) lactobacilli and coccobacilli amounts; and 6) squamous maturation (ratio of parabasal:intermediate:superficial cells).

RESULTS

No statistically significant differences were observed for blue blobs, histiocytes, blood, endometrial cells, or single or enlarged endocervical nuclei among smears from the three groups. More smears from DP and TP users demonstrated squamous cell curling, crowding, and cytolysis as well as navicular cells and abundant lactobacilli compared with smears from PM patients. There were more PM smears with pseudoparakeratosis and mucin-depleted endocervical cells compared with the other groups. The majority of PM smears (98%) demonstrated predominantly parabasal cells with some intermediate cells. The majority of DP (86%) and TP (93%) smears demonstrated mostly intermediate and some superficial cells, regardless of the duration of DP use.

CONCLUSIONS

Certain progestational-dependent effects (i.e., curling, crowding, navicular cells, and abundant lactobacilli) were identified more often in TP users compared with DP users and less often in PM patients. The mostly parabasal pattern observed in smears from PM patients contrasted with the predominantly intermediate pattern found in smears from DP and TP users. The duration of DP use did not appear to have any effect on squamous maturation.

Screening for cervical neoplasia in a developing country utilizing cytology, cervicography and the acetic acid test

OBJECTIVE

To compare three screening tests for cervical neoplasia.

METHOD

Women (6301) were screened simultaneously with cytology, cervicography and the acetic acid test (AAT). Biopsies were taken from the acetowhite lesions and every fifth seemingly normal cervix. Positive cases (both at screening and histology) were referred for colposcopy. The histology results served as the golden standard.

RESULTS

Cytology was positive in 1.7% of cases, cervicography in 10.7% and the AAT in 17.8%. The sensitivity of cytology was 19.3%, of cervicography 41.8% and the AAT 49.4%. Corresponding specificities were 99.3%, 78.8% and 48.5%. In 23% of biopsies showing cervical intraepithelial neoplasia (grade I--III), all three screening tests were negative. By combining the three tests, a sensitivity of 76.9% was achieved.

CONCLUSION

The sensitivity of cytology alone is not great enough for implementing as a screening test in a developing country where screening programs are often inadequate. Screening with a combination of tests, once or a few times per woman's life, is a more acceptable alternative since it allows for less screening events without sacrifying sensitivity.

Chien-Tien Hsu Memorial Lecture. Fertility and gynaecologic malignancies

Fertility and gynaecological malignancies have an important relationship. A clear inverse relationship exists between family size and the incidence of ovarian and endometrial cancer. Current methods of fertility control have an influence on subsequent development of various gynaecological malignancies. A slightly increased risk of breast cancer has been reported in current users and those who had used hormonal contraceptives (OCs) within 10 years; this risk declined with time and disappeared after 10 years. Women who started OC before age 20 had a higher relative risk; the disease did not spread beyond the breast in the majority. Most studies found OC to reduce the risk of ovarian and endometrial cancer. The relative risks of squamous cell carcinoma and adenomatous carcinoma of the cervix have been reported to be 1.3 and 1.5, respectively in ever-users of OCs; however, the aetiology of cervical cancer is multifactoral. Several reports suggest the beneficial effect of tubal ligation and breast feeding in reducing the risk of ovarian cancer. Therapy of gynaecological malignancies may have an influence on subsequent fertility. Amenorrhoea developing after treatment of hydatidiform mole may be due to choriocarcinoma, recurrent mole or a normal pregnancy. Choriocarcinoma can also develop after a partial mole. The risk of fetal teratogenicity from chemotherapy is present only if conception occurs during or immediately following the treatment cycles. Fertility is not impaired following chemotherapy. Successful pregnancies have occurred in women who have had widespread GTD including cerebral metastases. In the young patient with gynaecological malignancy preservation of fertility is possible. Fertility-sparing surgery may be safe in early ovarian epithelial cancers and even in advanced germ cell tumours. Recently, the fertility-sparing surgery of radical trachelectomy and pelvic lymphadenectomy has been carried out for early invasive cervical cancer in young women. Gynaecological cancer occurring in pregnancy is uncommon; it presents the clinician with a difficult situation to manage. In most instances the cancer is treated as though the patient is not pregnant; the timing and mode of delivery needs individualization. The overall prognosis for breast cancer complicating pregnancy is poor. Survival in cervical cancers diagnosed antepartum is similar to the non-pregnant patient. Ovarian cancer in pregnancy has a good prognosis because of the early stage at diagnosis.

Contraceptive and reproductive risk factors for cervical intraepithelial neoplasia in American Indian women

OBJECTIVES

To evaluate contraceptive and reproductive risk factors for cervical intraepithelial neoplasia (CIN) in southwestern American Indian women.

METHODS

We conducted a clinic-based case-control study. Cases were American Indian women with biopsy-proven CIN I, CIN II or CIN III. Controls were from the same clinics and had normal cervical epithelium. All subjects underwent structured interviews focused on contraceptive and reproductive factors. Laboratory assays included polymerase chain reaction (PCR)-based tests for cervical human papillomavirus (HPV) infection.

RESULTS

We enrolled 628 women in the study. The strongest risk factors for CIN II/III included HPV infection (adjusted odds ratio [OR] = 7.9, 95% CI : 4.7-13.2), and low income (OR = 3.1, 95% CI : 1.7-5.7). The use of an intrauterine device (IUD) ever (OR = 3.0, 95% CI : 1.4-6.1) and currently (OR = 4.1, 95% CI : 1.1-14.6), and > or = 3 vaginal deliveries (OR = 5.2, 95% CI : 2.4-11.1) were associated with CIN II/III. History of infertility was also associated with CIN II/III (OR = 2.1, 95% CI : 1.0-4.2).

CONCLUSIONS

The data suggest that history of infertility, IUD use and vaginal deliveries were associated with CIN among American Indian women.

Depot-medroxyprogesterone acetate (DMPA) and risk of invasive adenocarcinomas and adenosquamous carcinomas of the uterine cervix. WHO Collaborative Study of Neoplasia and Steroid Contraceptives

A hospital-based case-control study was conducted in two hospitals in Bangkok, Thailand, and in one hospital each in Chiang Mai, Thailand, Mexico City, Mexico and Nairobi, Kenya. One purpose of this study was to determine whether the long-acting progestational contraceptive, depot-medroxyprogesterone acetate (DMPA), alters risk of invasive cervical carcinomas with adenomatous histological features. Information on prior use of DMPA, screening for cervical cancer, and the suspected risk factors for this disease was ascertained from interviews of 239 women with adenocarcinomas and 85 women with adenosquamous carcinomas, as well of from a large pool of controls, 2534 of whom were matched to the cases included in this report. For selected subsets of these women, a smoking history was also elicited, blood specimens were collected for measurement of antibodies against herpes simplex and cytomegalovirus, and information on sexual behavior was obtained from interviews of their husbands. The relative risk (and 95% confidence interval) of adenomatous cervical carcinomas in women who ever used DMPA was estimated to be 0.75 (0.51, 1.11). No trends in risk were observed with duration of DMPA use, times since first or last use, or age at first use. The results provide reassurance that use of DMPA for over four years does not enhance risk of adenomatous cervical carcinomas, and risk is not increased after a potential latent period of over 12 years since initial exposure.