Endometriosis-associated ovarian cancer: A ten-year cohort study of women living in the Estrie Region of Quebec, Canada

Fertility drug use and risk of ovarian tumors: a debated clinical challenge

Infertility itself increases the incidence of ovarian carcinoma, while the potential additional risk associated with the use of fertility drugs is still debated. In 1992, the cumulative analysis of 12 US case-control studies revealed that women who received ovulation-inducing drugs had approximately three-fold higher incidence of invasive ovarian carcinoma. Other investigations reported a lower increase of the risk of invasive carcinoma or borderline tumor of the ovary in women treated with these agents. Conversely, several other case-control or cohort studies failed to detect a significant correlation between fertility drug use and ovarian tumor risk in either parous or nulliparous women compared with untreated infertile women. Moreover neither the number of treatment cycles nor the type of drug used was associated with an increased risk in most studies. Incessant ovulation and excessive gonadotropin secretion have been long considered to play a major role in the development of ovarian carcinoma, and therefore fertility drugs, which raise the serum levels of gonadotropins and increase the chances of multiple ovulations, have been retained as a risk factor for this malignancy, However, the large majority of literature data as well as the new hypotheses on ovarian carcinogenesis appear to exclude a relevant impact of fertility drug use on the risk of ovarian tumors, and especially of high-grade invasive epithelial ovarian cancers.

Transmembrane estrogen receptor GPR30 is more frequently expressed in malignant than benign ovarian endometriotic cysts and correlates with MMP-9 expression

OBJECTIVE

Molecular studies supporting the idea of malignant transformation of endometriosis are sparse and not well substantiated. The aims of this study were to detect expression levels of the novel estrogen-responsive receptor G protein-coupled estrogen receptor 1 GPER, also termed GPR30, and to determine its correlation with matrix metalloproteinase-9 (MMP-9) in benign and malignant ovarian endometriotic cysts and to explore the significance of GPR30.

METHODS

Immunohistochemical staining with the streptavidin-peroxidase method was conducted to determine the expression of GPR30 and MMP-9 in 24 cases of endometriosis-associated ovarian carcinoma (EAOC) and 32 specimens of ovarian endometriosis without malignant transformation. Reverse transcriptase polymerase chain reaction was performed to determine messenger RNA expression of GPR30 and MMP-9 in benign and malignant ovarian endometriotic cysts. We also investigated their associations with known clinic pathological parameters and the interrelationship between the expressions of the 2 proteins.

RESULTS

The positive staining ratio of GPR30 was 95.8% (23/24) in EAOC cases, and the HScore was 268; whereas the positive ratio was 25% (8/32) in benign endometriotic cysts, and the Hscore was 95. Matrix metalloproteinase-9 was expressed in all 24 EAOC cases and 87.5% (28/32) of the benign samples, and the Hscores were 280 and 260, respectively (P > 0.05). The receptor GPR30 was significantly higher in EAOCs than in benign endometriotic cysts (P < 0.05). The expression of GPR30 messenger RNA was also significantly higher in malignant ovarian endometriotic cysts than in the benign group. The receptor GPR30 was positively related to tumor size, tumor stage, and lymph node metastasis. A positive relationship between GPR30 and MMP-9 was found (P = 0.002).

CONCLUSIONS

The results suggest that the abnormal expression of GPR30 may be involved in malignant transformation, invasion, and metastasis of EAOCs. Testing of GPR30 expression levels may present both diagnostic and therapeutic options for the treatment of ovarian malignancies.

Molecular links between endometriosis and cancer

Endometriosis is the leading cause of morbidity among premenopausal women affecting about 1 in 10 females. The features shared by endometriosis and cancer include the ability to evade apoptosis, the stem cell-like ability and angiogenic potential. As such characteristics are encoded by the cell's genetic constitution, acquired mutations are responsible for the malignant transformation of endometriosis. Indeed, a number of tumour-suppressor genes and proto-oncogenes, such as protein 53 (P53) and B-cell lymphoma 2 (BCL-2) respectively, are mutated and as a result differentially expressed between endometriotic and malignant tissue associated with endometriosis. Moreover, cytokines and macrophages, both of which are inflammatory mediators have been implicated in the transformation process. The angiogenic properties possessed by cancer arising from endometriosis signifies a bad prognosis, while the stem cell-like activity possessed by both endometriosis and cancer has been attributed to the effect of oestrogen. A number of differences between endometriosis and cancer are found at the molecular level. Considering the link between these two pathologies, the three components which fuel the malignant transformation of endometriosis can be embodied in the endometriosis-induced carcinoma (EIC) triangle which shows the intricate relationship between endocrinologic, immunologic and genetic components.

Loss of ARID1A/BAF250a-expression in endometriosis: a biomarker for risk of carcinogenic transformation?

Mutations of the tumor-suppressor gene ARID1A result in the loss of protein expression of the BRG-associated factor 250a (BAF250a), a large subunit of transcription-regulating Human SWI/SNF complexes, which have an important role in the control of cell proliferation and tumor suppression. ARID1A mutations are particularly frequent in endometriosis-associated ovarian clear cell and endometrioid carcinomas, and were recently described as a possible key mechanism and early step in the transformation of endometriosis into cancer. Here, we examined the immunohistochemical expression pattern of BAF250a in a tissue microarray including 74 endometriosis and 30 endometrium samples. Ovarian cancer samples (n=136) served as a control. Epithelial BAF250a expression was assessable in 90/104 (87%) and stromal BAF250a expression in 95/104 (91%) of the endometriosis, and endometrium cases due to lack of adequate tissue in some spots. Complete lack of BAF250a expression was observed in three endometriomas (n=3/20, 15%) and one deep-infiltrating endometriosis sample (n=1/22, 5%), but in none of the peritoneal endometriosis (n=0/16) and eutopic endometrium samples (n=0/30). A comparison of the mean immunoreactivity scores revealed a significantly lower expression rate of BAF250a in endometriomas compared with normal endometrium (P<0.0005), as well as peritoneal (P=0.003) and deep-infiltrating endometriosis (P=0.02). Our data demonstrates that a complete loss of BAF250a expression is observable in some endometriotic lesions, especially in endometriomas. In addition, we report that a partial loss of BAF250a expression is occurring in the form of cell clusters indicating a clonal loss of BAF250a expression in these cells. The loss of expression of the tumor-suppressor protein BAF250a in some endometriomas possibly indicates a risk of malignant transformation in these cases, which could be of importance in the determination of individual treatment strategies. However, its role and value as a prognostic parameter in endometriosis needs to be further studied.

Clear cell carcinoma of the ovary: a review of the literature

OBJECTIVE

Different histologic types of epithelial ovarian cancer may represent different diseases with unique clinical and molecular characteristics. Clear cell carcinoma (CCC) of the ovary has been reported as having a worse prognosis than high grade serous epithelial ovarian cancer (EOC). This article critically reviews the literature pertinent to the pathology, pathogenesis, diagnosis, management, and outcome of patients with ovarian CCC.

METHODS

MEDLINE was searched for all research articles published in English between January 01, 1977 and January 30, 2012 which reported on patients diagnosed with ovarian CCC. Given the rarity of this tumor, studies were not limited by design or number of reported patients.

RESULTS

Ovarian CCC tumors represent 5-25% of ovarian cancers. Its histologic diagnosis can be challenging, resulting often times in misclassification of these tumors. Ovarian CCC tends to present at earlier stages and has been associated with endometriosis, ARID1A and PIK3CA mutations. When compared to stage-matched controls, patients with early-stage ovarian CCCs may have a better prognosis than patients with high-grade serous tumors. For those with advanced stage disease, high-grade serous histology confers a better prognosis than ovarian CCC. Patients with Stage IC-IV have a relatively poor prognosis and efforts should center in discovery of more effective treatment strategies.

CONCLUSIONS

Ovarian CCC is a biologically distinct entity, different from high-grade serous EOC. Future studies should explore the role of targeted therapies in the management of ovarian CCC.

Minimally invasive gynecologic procedures

PURPOSE OF REVIEW

To evaluate different surgical options for the treatment of endometriomas. A heated debate is currently under way between advocates of excisional surgery and the ablative approach. With papers increasingly focusing on ovarian reserve after endometrioma surgery, a review was mandatory.

RECENT FINDINGS

Excisional and ablative surgery are well known procedures. This paper describes a combined technique that allows preservation of ovarian volume and antral follicle count. The question of postoperative ovarian reserve is widely discussed and the risk of malignancy is addressed.

SUMMARY

Some previously published reviews have probably too hastily concluded that excision is a better option than ablation. They failed to analyze the ovarian reserve, which is often significantly decreased after excisional surgery.This manuscript clearly explains the crucial importance of preserving the ovarian blood supply, as well as the ovarian cortex containing all primordial follicles, during surgery.

The short form endometriosis health profile (EHP-5): translation and validation study of the Iranian version

BACKGROUND

Endometriosis Health Profile (EHP-5) is a valid instrument to measure health-related quality of life in endometriosis. This study was conducted to culturally adapt and validate the EHP-5 in Iran.

METHODS

Using a standard "forward-backward' translation procedure, the English language version of the questionnaire was translated into Persian (Iranian language). Then a sample of 199 women aged 18-50 years completed the questionnaire. To test reliability the internal consistency was assessed by Cronbach's alpha coefficient. Validity was evaluated using known groups comparison.

RESULTS

The mean age of respondents was 31.4 (SD = 5.4) years. Reliability analysis showed satisfactory result (Cronbach's alpha coefficient = 0.71). The questionnaire discriminated well between sub-groups of women differing in infertility and premenstrual syndrome (PMS) in the expected direction.

CONCLUSION

This preliminary validation study of the Iranian version of the EHP-5 proved that it is an acceptable, reliable and valid measure of quality of life in endometriosis patients.

Endometriosis and ovarian cancer: a systematic review

Introduction. Endometriosis is one of the most common benign disorders which affects 10-15% of all women in reproductive age. The association between endometriosis and ovarian cancer has been frequently described in the medical literature. Purpose. To evaluate the literature for evidence of a correlation between endometriosis and ovarian cancer. Method. the English language literature (online MEDLINE and EMBASE database) was searched using the keywords endometriosis combined with cancer, tumour, tumor, carcinoma, or adenocarcinoma. All abstracts between January 1985 and August 2010 were reviewed. Full relevant articles were critically assessed. Reference lists of included studies were checked. Results. Seven out of the eight studies, included in our review, have shown an increased risk of ovarian cancer. However, the effect size is modest (OR, RR, and SIR) ranging between 1.32 and 1.9 (95% CI). A causative relationship between the two incidences cannot be confirmed. There is increasing evidence on the role of genetic mutations in ovarian clear-cell and endometrioid carcinoma developing from endometriosis. Conclusion. More evidence is needed before suggesting any change in the current management of endometriosis.

Clear cell carcinoma of the ovary: a report from the first Ovarian Clear Cell Symposium, June 24th, 2010

OBJECTIVES

Recent literature has highlighted histological types of ovarian carcinoma as distinct diseases, each with unique clinical and molecular features. Historically, the diagnosis of ovarian clear cell carcinoma (CCC) has been of concern to both patients and physicians due to reports that CCC is associated with a worse prognosis than the more common serous type of ovarian carcinoma (HGSC). This review discusses the unique features of ovarian CCC.

METHODS

In June of 2010, a group of researchers and clinicians convened in Vancouver to review and discuss the clinical, pathological, molecular, and treatment-related features of CCC.

RESULTS

CCC is the second most common type of ovarian epithelial cancer, representing 5-25% of ovarian carcinomas. It is characterised by its association with endometriosis, and frequent mutations of ARID1A and PIK3CA. Low-stage CCC appears to have a better outcome than stage matched HGSC, while the opposite is true for high-stage disease, suggesting that the current standard treatments applied to HGSC are ineffective for CCC.

CONCLUSIONS

Ovarian CCC is highly distinct from HGSC, and a clearer understanding of the basic biology of this disease is needed. Alternative therapies should be explored: irradiation and targeting disease-specific molecular markers should be examined in greater detail. Finally, novel approaches to clinical trial design are needed due to the smaller numbers of patients affected.

Possible involvement of loss of heterozygosity in malignant transformation of ovarian endometriosis

OBJECTIVE

Although histological and epidemiological studies have suggested that endometriosis has malignant potential, the molecular mechanism underlying the malignant transformation of endometriosis is poorly understood. Ovarian cancer arising from endometriosis (OCEM) may provide an ideal model for genetic studies. To investigate the genetic alterations during transformation of ovarian endometriosis into cancer, we analysed loss of heterozygosity (LOH) and mutations of tumour-related genes in OCEM cases (n=12) that fulfilled the histological criteria and in solitary ovarian endometriosis (n=12).

METHODS

Each paraffin-embedded section was microdissected to isolate the endometriotic epithelium, transitional epithelium, and cancer cells. Extracted DNA was amplified by nested PCR. LOH was identified with fluorescence-labelled microsatellite markers. Mutations of tumour-related genes PTEN, TP53, and K-ras were examined by bidirectional DNA sequencing.

RESULTS

With 13 microsatellite markers on six chromosomes, we detected 31 and eight LOH events in OCEMs and in solitary ovarian endometriosis, respectively. In the OCEM group, 18 LOH events were found in cancer cells alone, while 13 LOH events were found in all cancer, transitional, and endometriotic tissues. High frequencies of LOH were detected on chromosomes 9p, 10q, and 13q. However, only two point mutations were detected in cancer cells in one case.

CONCLUSION

Our study suggested that accumulated LOH events on some chromosome loci may be involved in malignant transformation of endometriosis, while mutations in certain tumour-related genes are not.