Regression of latent endometrial precancers by progestin infiltrated intrauterine device

Incessant ovulation: a review of its importance in predicting cancer risk

Estrous cycles are recurring changes in therian mammals induced by estrogen, progesterone, and other hormones culminating in endometrial proliferation, ovulation, and implantation if fertilization occurred. In women, the estrous cycle is the menstrual cycle; but, unlike most mammals, the end of an infertile cycle is marked by endometrial sloughing and the start of another without an anestrous phase. Women stop cycling at menopause, while in most mammals, cycles continue until death. Epidemiologic studies identified menarche, menopause, births, lactation, and oral contraceptive (OC) use as key risk factors for ovarian, breast, and endometrial cancers. A composite variable was created to estimate the number of cycles not interrupted by events that stop ovulation. Captured by the phrase "incessant ovulation", repetitive cycles were first postulated to affect ovarian cancer risk and later extended to breast and endometrial cancers. These associations could be explained by cumulative effects of repetitive tissue changes within reproductive organs, immune consequences of repetitive ovulation through the glycoprotein mucin 1, and residual effects of past ovulations that enhance ovarian production of testosterone. The latter two pathways could affect the risk for cancers in other organs not considered "reproductive".

Levonorgestrel-releasing intrauterine system versus systemic progestins in management of endometrial hyperplasia: A systemic review and meta-analysis

INTRODUCTION

Endometrial hyperplasia is associated with varying risk of endometrial cancer. The aim of this review is to assess effectiveness of levonorgestrel-releasing intrauterine system (LNG-IUS), compared to systemic progestins, in management of endometrial hyperplasia MATERIALS AND METHODS: A search on studies comparing LNG-IUS to systemic progestins was conducted on Scopus, Web of science, Cochrane, PubMed and Embase databases, from the date of inception to September 20th, 2020. Studies were excluded if they were non-comparative, animal studies, review articles, case reports, case series, and conference papers. Primary outcomes include resolution/regression rate, failure rate, and hysterectomy rate. Analysis was pooled using random effect model and was expressed as pooled odds ratios (OR) and 95% confidence interval (CI). Quality assessment was performed using Cochrane Risk of Bias Tool and the Newcastle-Ottawa Scale (NOS) assessment tool. MOGGE Meta-analysis Matrix was used to illustrate multiple subgroup analyses.

RESULTS

Out of 341 studies retrieved from literature search, 12 were eligible. LNG-IUS yielded significantly higher resolution/regression rate (91.3% vs 68.6%, OR 3.42, 95% CI 1.86-6.30). Failure and hysterectomy rates were significantly lower in LNG-IUS group compared to systemic progestins' group (19.2% vs. 32.3%, OR 0.34, 95% CI 0.20-0.57 and 9.3% vs. 24.1%, OR 0.41, 95% CI 0.29-0.57, respectively). Subgroup analysis of studies including complex hyperplasia only did not show significant difference in resolution/regression rate was not statistically significant.

CONCLUSION

LNG-IUS is associated with high success rate in management of women with endometrial hyperplasia. However, specific effectiveness of LNG-IUS on more advanced histologic subtypes is less studied.

Specific Biomarker Expression Patterns in the Diagnosis of Residual and Recurrent Endometrial Precancers After Progestin Treatment: A Longitudinal Study

BACKGROUND

Conservative management with progestin is a treatment option for atypical hyperplasia (AH). However, pathologic diagnosis of residual/recurrent lesions is often problematic because of the profound morphologic changes induced by progestin and the lack of established diagnostic criteria for progestin-treated residual AH.

METHODS

We conducted a longitudinal study of 265 endometrial biopsies from 54 patients with a history of AH on progestin therapy. Patient outcomes were divided into 3 categories after morphologic review and immunohistochemical staining with phosphatase and tensin homolog (PTEN) and paired box 2 (PAX2): (1) persistent or residual disease; (2) recurrent disease; (3) complete response. All specimens were classified into 3 categories based on morphology: (1) persistent/recurrent disease (nonresponse), (2) morphologically uncertain response, (3) optimally treated (complete response). The staining patterns of PTEN/PAX2 were tracked over time in individual patients and correlated with morphologic findings before and after progestin therapy.

RESULTS

Our data showed that aberrant expression patterns of PTEN and/or PAX2 were identified in 48 (88.9%) of the 54 primary biopsies and persisted in persistent/recurrent AH across serial endometrial biopsies (n=99, P<0.00001), while normal PTEN and PAX2 expressions were consistently observed in optimally treated cases (n=84, P<0.00001). More importantly, follow-up biopsies that showed a morphologically uncertain response but a PTEN/PAX2 expression pattern identical to the initial biopsy were significantly correlated with persistent or recurrent disease (n=18, P=0.000182), as evidenced by areas with morphologic features diagnostic of AH on subsequent biopsy.

CONCLUSIONS

Biomarker PTEN/PAX2 signatures offer a valuable diagnostic aid to identify residual AH in progestin-treated endometrial samples for which the biomarker status from preprogestin treated AH is known. The findings of this study are promising for a possible future change of diagnostic practice.

PROgesterone Therapy for Endometrial Cancer Prevention in Obese Women (PROTEC) Trial: A Feasibility Study

Obesity is the major etiologic driver for endometrial cancer. The levonorgestrel intrauterine system (LNG-IUS) reduces the risk of endometrial cancer and its precursor, atypical hyperplasia. We assessed feasibility and uptake of the LNG-IUS for primary prevention of endometrial cancer in high-risk women and its impact on endometrial tissue biomarkers. Women with class-III obesity [body mass index (BMI) > 40 kg/m²] and histologically normal endometrium were invited to participate in a clinical trial of the LNG-IUS for endometrial protection. Recruitment, successful LNG-IUS insertion, and adherence to trial procedures were recorded. We measured impact of the LNG-IUS on circulating biomarkers of endometrial cancer risk, endometrial proliferation (Ki-67, pAKT, PTEN), endometrial hormone receptor status [estrogen receptor and progesterone receptor (PR)], mental wellbeing, and menstrual function. At 6 months, women chose to keep their LNG-IUS or have it removed. In total, 103 women were approached, 54 were offered a participant information sheet, 35 agreed to participate, and 25 received a LNG-IUS. Their median age and BMI were 54 years [interquartile range (IQR) 52-57] and 47 kg/m² (IQR 44-51), respectively. Three women (3/35, 9%) were ineligible due to atypical hyperplasia/endometrial cancer on their baseline biopsy. The LNG-IUS was well tolerated and had a positive overall effect on bleeding patterns and mental wellbeing. The LNG-IUS was associated with endometrial morphologic change, reduced Ki-67, and PR expression, but circulating biomarkers of endometrial cancer risk were unchanged. All but one woman (96%) kept her LNG-IUS. The LNG-IUS appears to be acceptable to some women with class-III obesity for primary prevention of endometrial cancer, which could provide a strategy for a prevention trial.Prevention Relevance: Novel strategies are urgently needed to prevent the rise in endometrial cancer diagnoses predicted by escalating obesity rates. Here, we show that women with class III obesity are willing to engage in risk reduction with a levonorgestrel intrauterine system, which could provide a strategy for an endometrial cancer prevention trial.

Frequent loss of mutation-specific mismatch repair protein expression in nonneoplastic endometrium of Lynch syndrome patients

Lynch syndrome is most often caused by a germline mutation in one of four DNA mismatch repair (MMR) genes (MLH1, PMS2, MSH2, or MSH6) or EPCAM and is associated with a significantly increased risk of endometrial cancer in affected women. Although universal screening of endometrial cancer for Lynch syndrome is becoming increasingly common by various algorithms using MMR immunohistochemistry and/or microsatellite instability testing by PCR, establishing the diagnosis of Lynch syndrome can be still challenging. MMR-deficient nonneoplastic colonic crypts have been recently described in Lynch syndrome patients with colorectal carcinoma, and have been proposed to be a novel indicator of Lynch syndrome. Presence of MMR-deficient nonneoplastic endometrial glands have not yet been systematically evaluated in Lynch syndrome patients. We performed MMR protein immunohistochemistry in prophylactic hysterectomies and endometrial curettings/biopsies from 27 patients with known Lynch syndrome confirmed by germline mutation analysis. A total of 56 control benign endometrial tissues were also analyzed, and included benign endometrium adjacent to MMR-deficient sporadic (MLH1 promoter hypermethylated) endometrial carcinoma (n = 9), adjacent to MMR-intact sporadic endometrial carcinoma (n = 27), and normal endometrium from hysterectomies performed for benign disease (n = 20). MMR protein deficient nonneoplastic endometrial glands were identified in 70% (19 of 27) of Lynch syndrome patients. In all 19 cases the MMR protein loss was specific for the patients' known germline mutation. None of the control cases showed loss of MMR protein expression in nonneoplastic endometrium. Our findings suggest that MMR-deficient nonneoplastic endometrial glands may be a unique, specific marker of Lynch syndrome, and may provide an important insight into the pathogenesis of Lynch syndrome-associated endometrial cancer. Evaluation of MMR protein expression of benign background endometrium in endometrial cancer patients may be further explored as a possible useful addition to the Lynch syndrome screening algorithm.

The impact of obesity and bariatric surgery on circulating and tissue biomarkers of endometrial cancer risk

Obesity is the strongest risk factor for endometrial cancer (EC). To inform targeted screening and prevention strategies, we assessed the impact of obesity and subsequent bariatric surgery-induced weight loss on endometrial morphology and molecular pathways implicated in endometrial carcinogenesis. Blood and endometrial tissue were obtained from women with class III-IV obesity (body mass index ≥40 and ≥50 kg/m2 , respectively) immediately prior to gastric bypass or sleeve gastrectomy, and at two and 12 months' follow up. The endometrium underwent pathological examination and immunohistochemistry was used to quantify proliferation (Ki-67), oncogenic signaling (PTEN, pAKT, pERK) and hormone receptor (ER, PR) expression status. Circulating biomarkers of insulin resistance, reproductive function and inflammation were also measured at each time point. Seventy-two women underwent bariatric surgery. At 12 months, the mean change in total and excess body weight was -32.7 and -62.8%, respectively. Baseline endometrial biopsies revealed neoplastic change in 10 women (14%): four had EC, six had atypical hyperplasia (AH). After bariatric surgery, most cases of AH resolved (5/6) without intervention (3/6) or with intrauterine progestin (2/6). Biomarkers of endometrial proliferation (Ki-67), oncogenic signaling (pAKT) and hormone receptor status (ER, PR) were significantly reduced, with restoration of glandular PTEN expression, at 2 and 12 months. There were reductions in circulating biomarkers of insulin resistance (HbA1c, HOMA-IR) and inflammation (hsCRP, IL-6), and increases in reproductive biomarkers (LH, FSH, SHBG). We found an unexpectedly high prevalence of occult neoplastic changes in the endometrium of women undergoing bariatric surgery. Their spontaneous reversal and accompanying down-regulation of PI3K-AKT-mTOR signaling with weight loss may have implications for screening, prevention and treatment of this disease.

Selective progesterone receptor modulator (SPRM) ulipristal acetate (UPA) and its effects on the human endometrium

STUDY QUESTION

What is the impact of administration of the selective progesterone receptor modulator (SPRM), ulipristal acetate (UPA) on the endometrium of women with fibroids?

SUMMARY ANSWER

UPA administration altered expression of sex-steroid receptors and progesterone-regulated genes and was associated with low levels of glandular and stromal cell proliferation.

WHAT IS KNOWN ALREADY

Administration of all SPRM class members results in PAEC (progesterone receptor modulator associated endometrial changes). Data on the impact of the SPRM UPA administration on endometrial sex-steroid receptor expression, progesterone (P)-regulated genes and cell proliferation are currently lacking.

STUDY DESIGN SIZE, DURATION

Observational study with histological and molecular analyses to delineate impact of treatment with UPA on endometrium. Endometrial samples (n = 9) were collected at hysterectomy from women aged 39 to 49 with uterine fibroids treated with UPA (oral 5 mg daily) for 9-12 weeks. Control proliferative (n = 9) and secretory (n = 9) endometrium from women aged 38-52 with fibroids were derived from institutional tissue archives.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Study setting was a University Research Institute. Endometrial biopsies were collected with institutional ethical approval and written informed consent. Concentrations of mRNAs encoded by steroid receptors, P-regulated genes and factors in decidualised endometrium were quantified with qRT-PCR. Immunohistochemistry was employed for localization of progesterone (PR, PRB), androgen (AR), estrogen (ERα) receptors and expression of FOXO1, HAND2, HOXA10, PTEN homologue. Endometrial glandular and stromal cell proliferation was objectively quantified using Ki67.

MAIN RESULTS AND THE ROLE OF CHANCE

UPA induced morphological changes in endometrial tissue consistent with PAEC. A striking change in expression patterns of PR and AR was detected compared with either proliferative or secretory phase samples. There were significant changes in pattern of expression of mRNAs encoded by IGFBP-1, FOXO1, IL-15, HAND2, IHH and HOXA10 compared with secretory phase samples consistent with low agonist activity in endometrium. Expression of mRNA encoded by FOXM1, a transcription factor implicated in cell cycle progression, was low in UPA-treated samples. Cell proliferation (Ki67 positive nuclei) was lower in samples from women treated with UPA compared with those in the proliferative phase.

LARGE SCALE DATA

N/A.

LIMITATIONS REASONS FOR CAUTION

A small number of well-characterized patients were studied in-depth. The impacts on morphology, molecular and cellular changes with SPRM, UPA administration on symptom control remains to be determined.

WIDER IMPLICATIONS OF THE FINDINGS

P plays a pivotal role in endometrial function. P-action is mediated through interaction with the PR. These data provide support for onward development of the SPRM class of compounds as effective long-term medical therapy for heavy menstrual bleeding.

STUDY FUNDING/COMPETING INTEREST(S)

H.O.D.C. received has clinical research support for laboratory consumables and staff from Bayer Pharma Ag and provides consultancy advice (no personal remuneration) for Bayer Pharma Ag, PregLem SA, Gedeon Richter, Vifor Pharma UK Ltd, AbbVie Inc.; A.R.W.W. has received consultancy payments from Bayer, Gedeon Richter, Preglem SA, HRA Pharma; L.H.R.W., A.A.M., R.M., G.S. and P.T.K.S. have no conflicts of interest. Study funded in part from each of: Medical Research Council (G1002033; G1100356/1; MR/N022556/1); National Health Institute for Health Research (12/206/520) and TENOVUS Scotland.

The yield of endometrial aspiration in women with various risk factors and bleeding abnormalities

Background

Even in the face of a substantial increase in the numbers of endometrial cancer cases and in the numbers of women who have risk factors, there is no clear agreement about the indications for assessing the endometria of women with abnormal bleeding or about the tools to use in that assessment. This study sought to determine in a group of high risk women with abnormal uterine bleeding, the probability that an outpatient endometrial aspiration would identify significant pathology.

Methods

Retrospective cohort study of the histology from endometrial aspirations performed from 2001 to 2008 for abnormal uterine bleeding at Harbor-UCLA Medical Center and its satellite public health clinics. Medical records were reviewed in detail to assess risk factors, descriptions of bleeding abnormalities and histologic results.

Results

The charts of 1601 women who underwent 1636 endometrial biopsies for a wide variety of abnormal uterine bleeding patterns yielded 73 (4.6 %) cases of endometrial carcinoma, 43 cases of atypical endometrial hyperplasia (2.7 %), for an overall yield of significant pathology of 7.2 %. Hyperplasia without atypia was found in another 83 cases (5.2 %). Obesity, diabetes and postmenopausal age are associated with an increased risk of significant pathology. Bleeding patterns were so poorly documented that analysis of yield by this factor should be viewed with caution.

Conclusions

The probability of detecting significant uterine pathology is greatest among obese, diabetic postmenopausal women with diabetes (26.3 %). Conversely, the probability of identifying significant pathology in younger women without risk factors is less than 2 %. For women who perceive their individualized risk estimate to be too small to justify an endometrial biopsy, it may be possible to offer oral higher dose progestin therapy on the condition that persistent abnormal bleeding will require more intensive evaluation. These estimates of absolute risk of being diagnosed with significant pathology on endometrial biopsy may be helpful to patients as they consider giving informed consent for the procedure.

Tumor progression, metastasis, and modulators of epithelial-mesenchymal transition in endometrioid endometrial carcinoma: an update

Endometrioid endometrial carcinoma (EEC), also known as type 1 endometrial cancer (EC), accounts for over 70-80% of all cases that are usually associated with estrogen stimulation and often develops in a background of atypical endometrial hyperplasia. The increased incidence of EC is mainly confined to this type of cancer. Most EEC patients present at an early stage and generally have a favorable prognosis; however, up to 30% of EEC present as high risk tumors, which have invaded deep into the myometrium at diagnosis and progressively lead to local or extra pelvic metastasis. The poor survival of advanced EC is related to the lack of effective therapies, which can be attributed to poor understanding of the molecular mechanisms underlying the progression of disease toward invasion and metastasis. Multiple lines of evidence illustrate that epithelial-mesenchymal transition (EMT)-like events are central to tumor progression and malignant transformation, endowing the incipient cancer cell with invasive and metastatic properties. The aim of this review is to summarize the current knowledge on molecular events associated with EMT in progression, invasion, and metastasis of EEC. Further, the role of epigenetic modifications and microRNA regulation, tumor microenvironment, and microcystic elongated and fragmented glands like invasion pattern have been discussed. We believe this article may perhaps stimulate further research in this field that may aid in identifying high risk patients within this clinically challenging patient group and also lead to the recognition of novel targets for the prevention of metastasis - the most fatal consequence of endometrial carcinogenesis.

(Partial) Loss of BAF250a (ARID1A) in rectovaginal deep-infiltrating endometriosis, endometriomas and involved pelvic sentinel lymph nodes

STUDY HYPOTHESIS

Loss of protein BAF250a (ARID1A) expression is present in women with rectovaginal deep-infiltrating endometriosis (DIE) and endometriosis affecting the pelvic sentinel lymph nodes (PSLN).

STUDY FINDING

Partial loss of protein BAF250a was found in some of our patient samples, comprising all endometriosis entities, including rectovaginal DIE and endometriosis affecting the PSLN.

WHAT IS KNOWN ALREADY

Loss of BAF250a (BRG-associated factor 250a)/ARIDIA (AT-rich interactive domain 1A) protein expression was identified among endometriosis-associated ovarian carcinomas and ovarian endometriosis, and this phenomenon was described as a possible early event in the transformation of endometriosis into cancer. DIE affecting the bowel/rectovaginal site is the most aggressive presentation of endometriosis and its 'risk' of malignant transformation has not been studied so far.

STUDY DESIGN, SAMPLES/MATERIALS, METHODS

We evaluated the immunohistochemical expression of BAF250a protein in 70 samples from patients enrolled in this study who were surgically treated at a tertiary center, university Hospital. The samples submitted to investigation were from rectovaginal DIE (n= 25/30), endometriosis affecting the PSLN (n= 5/7), ovarian endometriosis (n= 20/20) and endometrium from patients without endometriosis used as controls (n= 20/20).

MAIN RESULTS AND THE ROLE OF CHANCE

Partial loss (i.e. in one tissue section some cells stained positive for BAF250a while other cells, usually an adjacent group, were negative) of BAF250a protein was identified in 36% (9/25) of rectovaginal DIE samples, 40% (2/5) of endometriosis lesions involving the PSLN, 30% (6/20) of endometriomas, and also in 25% (5/20) of endometrium from controls. We found no statistical correlation between occurrence of partial loss of BAF250a protein and the use or not of hormone medications (P = 0.106), cycle phase (P = 0.917) and stage of disease (P = 0.717).

LIMITATIONS, REASONS FOR CAUTION

We only found partial loss of BAF250a protein expression, and in a small population of women, with relatively high frequency in all benign tissues assessed in the present analysis. Therefore, this finding alone should not be correlated directly with the risk of malignant transformation in these lesions.

WIDER IMPLICATIONS OF THE FINDINGS

The occurrence of partial loss of BAF250a protein expression in women with rectovaginal DIE and endometriosis affecting the PSLN is described for the first time. The value of this finding as a predictor of malignant transformation in endometriosis must still be clarified and further studied in association with other molecular events, such as PTEN (phosphatase and tensin homolog) deletion and PIK3CA (phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha) mutation. We might then be able to identify in the future which patients with endometriosis are at higher risk of cancer.

STUDY FUNDING AND COMPETING INTERESTS

This study was supported by an internal Charité grant to the Endometriosis Research Center and the authors declare no conflicts of interest.

Emergence, involution, and progression to carcinoma of mutant clones in normal endometrial tissues

Sporadic somatic inactivation of genes such as PTEN within histologically normal endometrium (latent precancers) is an early step in endometrial carcinogenesis. We have used clone-specific mutations of PTEN to determine the fate of latent precancers over time in women who do (high risk) and do not (low risk) develop endometrial neoplasia. PTEN immunohistochemistry was performed on 45 occurrences of endometrial neoplasia and their paired antecedent benign biopsies, along with age matched sample pairs from 167 patients who did not develop a neoplasm. When PTEN-deficient cells were present at both time points, DNA sequencing was performed to determine whether they were single or multiple independent events. Loss of PTEN protein in isolated glands was common in the initial normal biopsies of high- and low-risk groups (42% and 27%, respectively, P = 0.066). Protein-deficient glands have a tendency to disappear over time in low-risk women (P = 0.047) and, even when "persistent," are infrequently (19%, 3/16) confirmed to be the same clone. Similarly, only a small proportion (6.7%, 1/15) of latent precancers seen in high-risk women are the direct progenitors of subsequent neoplasia. There is a high rate of latent precancer turnover in both low- and high-risk patients, with rare long-term persistence of unique clones, which may or may not progress to a histologic lesion. The temporal dynamics of clonal emergence, persistence, and involution are sufficiently complex that in the individual patient, the presence of a latent precancer has an unknown contribution to long-term cancer risk.

Progesterone receptor signaling in the microenvironment of endometrial cancer influences its response to hormonal therapy

Progesterone, an agonist for the progesterone receptor (PR), can be an efficacious and well-tolerated treatment in endometrial cancer. The clinical use of progesterone is limited because of the lack of biomarkers that predict hormone sensitivity. Despite its efficacy in cancer therapy, mechanisms and site of action for progesterone remain unknown. Using an in vivo endometrial cancer mouse model driven by clinically relevant genetic changes but dichotomous responses to hormonal therapy, we show that signaling through stromal PR is necessary and sufficient for progesterone antitumor effects. Endometrial cancers resulting from epithelial loss of PTEN (PTENKO) were hormone sensitive and had abundant expression of stromal PR. Stromal deletion of PR as a single genetic change in these tumors induced progesterone resistance indicating that paracrine signaling through the stroma is essential for the progesterone therapeutic effects. A hormone-refractory endometrial tumor with low levels of stromal PR developed when activation of KRAS was coupled with PTEN-loss (PTENKO/Kras). The innate progesterone resistance in PTENKO/Kras tumors stemmed from methylation of PR in the tumor microenvironment. Add-back of stromal PR expressed from a constitutively active promoter sensitized these tumors to progesterone therapy. Results show that signaling through stromal PR is sufficient for inducing hormone responsiveness. Our findings suggest that epigenetic derepression of stromal PR could be a potential therapeutic target for sensitizing hormone-refractory endometrial tumors to progesterone therapy. On the basis of these results, stromal expression of PR may emerge as a reliable biomarker in predicting response to hormonal therapy.

Endometrial intraepithelial neoplasia

Endometrial intraepithelial neoplasia (EIN) is a monoclonal premalignant endometrial glandular lesion that precedes the development of endometrioid-type endometrial adenocarcinoma. EIN arises through complex interactions involving the sequential accumulation of genetic damage in endometrial glands and the positive selective pressure of unopposed estrogen. Recent data have revealed a preclinical latent precursor lesion composed of mutated but morphologically nondescript glands that may persist for years in normal-appearing premenopausal cycling endometrium. This latent precursor shares many of the molecular features of EIN and endometrial adenocarcinoma, including frequent inactivation of both the tumor suppressor gene PTEN and the paired box-containing gene PAX2. Upon progression to EIN, the distinctive appearance of crowded and cytologically altered glands heralds a 45-fold increased risk of developing endometrial adenocarcinoma. To preserve the high predictability of EIN for concurrent/ subsequent adenocarcinoma, strict adherence to defined diagnostic criteria is essential. These criteria, as well as potential diagnostic pitfalls and their resolution, are discussed herein.

Non-contraceptive health benefits of intrauterine hormonal systems

Non-contraceptive health benefits are now recognized as an important aspect of the overall impact of all hormonal contraceptives. The levonorgestrel-releasing intrauterine systems (LNG IUS) are particularly effective at producing a number of health benefits for women using the LNG IUS as a contraceptive (reduced menstrual bleeding; reduced dysmenorrhea and the potential for prevention of a number of gynecological conditions in the longer term, such as iron-deficiency anemia, endometrial hyperplasia, uterine fibroids, acute episodes of pelvic inflammatory disease, endometriosis and perhaps others). The LNG IUS also has the potential to specifically treat a range of pre-existing gynecological conditions such as heavy menstrual bleeding due to a wide range of underlying causes, endometrial hyperplasia, uterine fibroids, adenomyosis, and endometriosis. These health benefits should be recognized as a key component in the decision-making process for individual women in choosing a specific type of hormonal or other contraceptive. Investment in research into the very substantial health benefits of hormonal contraceptives, such as the LNG IUS, has generally been ignored in comparison with the massive investment into understanding the often subtle or rare complications of hormonal contraceptive use. Both are important, but there is a real need to define more accurately those women who will benefit most from these health benefits.

Cell-autonomous activation of the PI3-kinase pathway initiates endometrial cancer from adult uterine epithelium

Epithelial-specific activation of the PI3-kinase pathway is the most common genetic alteration in type I endometrial cancer. In the majority of these tumors, PTEN expression is lost in the epithelium but maintained in tumor stroma. Currently reported PTEN knockout mouse models initiate type I endometrial cancer concomitant with loss of PTEN in both uterine epithelium and stroma. Consequently, the biologic outcome of selectively activating the PI3-kinase pathway in the endometrial epithelium remains unknown. To address this question, we established a malleable in vivo endometrial regeneration system from dissociated murine uterine epithelium and stroma. Regenerated endometrial glands responded to pharmacologic variations in hormonal milieu similar to the native endometrium. Cell-autonomous activation of the PI3-kinase pathway via biallelic loss of PTEN or activation of AKT in adult uterine epithelia in this model was sufficient to initiate endometrial carcinoma. AKT-initiated tumors were serially transplantable, demonstrating permanent genetic changes in uterine epithelia. Immunohistochemistry confirmed loss of PTEN or activation of AKT in regenerated hyperplastic glands that were surrounded by wild-type stroma. We demonstrate that cell-autonomous activation of the PI3-kinase pathway is sufficient for the initiation of endometrial carcinoma in naive adult uterine epithelia. This in vivo model provides an ideal platform for testing the response of endometrial carcinoma to targeted therapy against this common genetic alteration.

Joint loss of PAX2 and PTEN expression in endometrial precancers and cancer

Latent endometrial carcinoma precancers are normal-appearing endometrial glands with sporadic loss of tumor suppressor gene function such as PTEN. Progression to carcinoma is inefficient and requires additional genetic damage that creates a histologic precursor lesion called endometrial intraepithelial neoplasia (EIN). In this study, we examined loss of PAX2 expression, a gene required for embryonic uterine development, during endometrial carcinogenesis. Normal proliferative, EIN, and malignant (endometrial adenocarcinoma) endometrial tissues were immunostained for PTEN and PAX2. Proliferative samples with loss of protein in at least one gland were scored as latent precancers. EIN and cancer lesions were scored by the majority pattern. Overall prevalence and topography of joint PAX2-PTEN expression loss was examined. The prevalence of PAX2 protein loss in the sequence of normal to precancer to cancer was 36%, 71%, and 77%, respectively, and for PTEN, it was 49%, 44%, and 68%, respectively. The normal endometrial prevalence of PAX2- or PTEN-deficient latent precancers was unaffected by biopsy indication, but increased significantly with age. Coincident loss of PAX2 and PTEN expression in an individual normal endometrium was seen in 21% of patients, but usually involved different glands. Coincident loss was more common in precancers (31%) and carcinoma (55%), in which case, both markers were protein null in an overlapping clonal distribution. PAX2 and PTEN protein loss occurs independently and accumulates with increasing age in latent precancers of normal premenopausal endometrium. Loss of function of both genes in an overlapping distribution characterizes the clinical emergence of a premalignant lesion which is carried forward to carcinoma.

Involution of latent endometrial precancers by hormonal and nonhormonal mechanisms

BACKGROUND

Inactivation of the PTEN suppressor gene has been shown to occur in the majority of endometrial cancer cases. Somatic PTEN inactivation by deletion and/or mutation, the first detectible change of endometrial carcinogenesis, has been reported to occur at a high frequency in the endometrium of normal premenopausal women, although few of these cases progress to cancer. It was hypothesized that the 50% to 60% reduced cancer risk attributed to oral contraceptives (OCPs) and intrauterine devices (IUDs) occurred in part through their activity as negative selection factors for these subclinical mutated glands.

METHODS

A total of 71 women with a history of OCP use and 80 with a history of IUD use were age matched with 191 and 119 controls, respectively. Endometrial biopsy specimens were immunostained for PTEN, and each was scored for the presence or absence of PTEN-null glands (latent precancer).

RESULTS

The frequency of latent precancers was found to be significantly reduced in OCP-exposed (13%; odds ratio [OR], 0.19 [P < .001]) and IUD-exposed (18%; OR, 0.42 [P = .015]) women compared with respective matched controls (43% and 34%). The presence or absence of endometritis did not appear to be significantly correlated with PTEN status within the IUD-exposed group (P = .24).

CONCLUSIONS

Normal-appearing PTEN mutated endometrial glands, which are highly prevalent in the normal population, may be targets of endometrial cancer risk-modulating exposures. Some exposures reported to diminish the incidence of endometrial cancer in epidemiologic outcome studies, including OCP and IUD use, are associated with a proportionate decline in the frequency of latent precancers. Involution of pre-existing endometrial latent precancers, as evaluated by PTEN analysis, may provide an accessible surrogate marker for long-term endometrial cancer risk.

Effect of asoprisnil on uterine proliferation markers and endometrial expression of the tumour suppressor gene, PTEN

BACKGROUND

The selective progesterone receptor modulator asoprisnil suppresses uterine bleeding and decreases leiomyoma volume while maintaining follicular phase estrogen concentrations. For safety of potential clinical applications, any proliferative effect of asoprisnil on uterine tissues, particularly endometrium, needs to be established.

METHODS

In a double-blind, randomized, placebo-controlled study (continuation of previously published trial No. NCT00150644 (Williams et al., 2007 and Wilkens et al., 2008)), 33 patients with symptomatic uterine leiomyomata received placebo, 10 or 25 mg asoprisnil daily for 12 weeks before hysterectomy. Proliferation markers Ki-67 and anti-phospho-histone H3 (PH3) were immunolocalized in endometrium, myometrium and leiomyoma tissue. Endometrial PTEN (phosphatase and tensin homologue, a tumour suppressor gene) expression was also assessed by immunohistochemistry. PH3-positive glandular and stromal cells were counted per measured endometrial area. Endometrial Ki-67 expression was assessed using stereological methods. Stained myometrial and leiomyoma cells were counted per 10 fields (x250). PTEN immunostaining was quantified using a histoscore. Each asoprisnil group was compared with placebo (secretory phase) with significance at 0.05 level.

RESULTS

Endometrial epithelial proliferation and PTEN expression were not significantly different between placebo and asoprisnil groups. Decreased stromal Ki-67 expression (P < 0.05) suggested any effect of asoprisnil on endometrial proliferation to be inhibitory. Immunolocalization of PTEN expression was not different between treatment groups in any tissue compartments. Myometrial Ki-67 expression decreased following asoprisnil 25 mg (P < 0.05).

CONCLUSIONS

Asoprisnil does not induce proliferation of uterine tissues and does not suppress endometrial PTEN expression.

Cost-effectiveness analysis of prevention strategies for gynecologic cancers in Lynch syndrome

BACKGROUND

Women with Lynch syndrome (hereditary nonpolyposis colorectal cancer) have an increased lifetime risk for endometrial and ovarian cancer. Screening and prophylactic surgery have been recommended as prevention strategies. In this study, the authors estimated the net health benefits and cost-effectiveness of these strategies in a Markov decision-analytic model.

METHODS

Five strategies were compared for a hypothetical cohort of women with Lynch syndrome: 1) no prevention ('reference'); 2) prophylactic surgery (hysterectomy and bilateral salpingo-oophorectomy) at age 30 years; 3) prophylactic surgery at age 40 years; 4) annual screening with endometrial biopsy, transvaginal ultrasound, and CA 125 from age 30 years; and 5) annual screening from age 30 years until prophylactic surgery at age 40 years (combined strategy). Net health benefit was measured in quality-adjusted life years (QALYs), and the primary outcome measured was the incremental cost-effectiveness ratio (ICER). Baseline and transition probabilities were obtained from published literature, and costs were from the U.S. Department of Health and Human Services and Agency for Health Care Quality and Research. Sensitivity analyses were performed for uncertainty around various parameters.

RESULTS

The combined strategy provided the highest net health benefit (18.98 QALYs) but had an ICER of $194,650 per QALY relative to the next best strategy (prophylactic surgery at age 40 years). Prophylactic surgery at age 30 years and annual screening were dominated by alternate strategies.

CONCLUSIONS

Annual screening followed by prophylactic surgery at age 40 years was the most effective gynecologic cancer prevention strategy, but the incremental benefit over prophylactic surgery alone was attained at substantial cost. The ICER would become favorable by improving the effectiveness and reducing the costs of screening in this population.

Intrauterine contraception: the pendulum swings back

Intrauterine contraception is the most widely used method of reversible fertility regulation in the world. Finally, IUC is undergoing a renaissance in the US and it's role will expand as new devices and systems are developed and as old biases among clinicians and women are erased. Successful fertility regulation is a defining factor of the overall health of a population; the expanded use of IUC can help achieve that public health success.

Multicenter Phase II Study of Fertility-Sparing Treatment With Medroxyprogesterone Acetate for Endometrial Carcinoma and Atypical Hyperplasia in Young Women

Purpose

To assess the efficacy of fertility-sparing treatment using medroxyprogesterone acetate (MPA) for endometrial carcinoma (EC) and atypical endometrial hyperplasia (AH) in young women.

Patients and Methods

This multicenter prospective study was carried out at 16 institutions in Japan. Twenty-eight patients having EC at presumed stage IA and 17 patients with AH at younger than 40 years of age were enrolled. All patients were given a daily oral dose of 600 mg of MPA with low-dose aspirin. This treatment continued for 26 weeks, as long as the patients responded. Histologic change of endometrial tissue was assessed at 8 and 16 weeks of treatment. Either estrogen-progestin therapy or fertility treatment was provided for the responders after MPA therapy. The primary end point was a pathologic complete response (CR) rate. Toxicity, pregnancy rate, and progression-free interval were secondary end points.

Results

CR was found in 55% of EC cases and 82% of AH cases. The overall CR rate was 67%. Neither therapeutic death nor irreversible toxicities were observed; however, two patients had grade 3 body weight gain, and one patient had grade 3 liver dysfunction. During the 3-year follow-up period, 12 pregnancies and seven normal deliveries were achieved after MPA therapy. Fourteen recurrences were found in 30 patients (47%) between 7 and 36 months.

Conclusion

The efficacy of fertility-sparing treatment with a high-dose of MPA for EC and AH was proven by this prospective trial. Even in responders, however, close follow-up is required because of the substantial rate of recurrence.

Copper IUD and LNG IUS compared with tubal occlusion

This article will cover current contraceptive use around the world, then examine the advantages and disadvantages of female sterilization, the hormonal intrauterine system and the copper intrauterine device. Finally, the need for contraceptive choice will be discussed along with a discussion on the cost-effectiveness of these methods.