Cancer risks associated with the diagnosis of infertility

Risk of ovarian cancer in women treated with ovarian stimulating drugs for infertility

BACKGROUND

This is an updated version of the original Cochrane Review published in the Cochrane Library in 2013 (Issue 8) on the risk of ovarian cancer in women using infertility drugs when compared to the general population or to infertile women not treated. The link between fertility drugs and ovarian cancer remains controversial.

OBJECTIVES

To evaluate the risk of invasive ovarian cancer and borderline ovarian tumours in women treated with ovarian stimulating drugs for subfertility.

SEARCH METHODS

The original review included published and unpublished observational studies from 1990 to February 2013. For this update, we extended the searches from February 2013 to November 2018; we evaluated the quality of the included studies and judged the certainty of evidence by using the GRADE approach. We have reported the results in a Summary of findings table to present effect sizes across all outcome types.

SELECTION CRITERIA

In the original review and in this update, we searched for randomised controlled trials (RCTs) and non-randomised studies and case series including more than 30 participants.

DATA COLLECTION AND ANALYSIS

At least two review authors independently conducted eligibility and 'Risk of bias' assessments and extracted data. We grouped studies based on the fertility drug used for two outcomes: borderline ovarian tumours and invasive ovarian cancer. We conducted no meta-analyses due to expected methodological and clinical heterogeneity.

MAIN RESULTS

We included 13 case-control and 24 cohort studies (an additional nine new cohort and two case-control studies), which included a total of 4,684,724 women.Two cohort studies reported an increased incidence of invasive ovarian cancer in exposed subfertile women compared with unexposed women. One reported a standardised incidence ratio (SIR) of 1.19 (95% confidence interval (CI) 0.54 to 2.25) based on 17 cancer cases. The other cohort study reported a hazard ratio (HR) of 1.93 (95% CI 1.18 to 3.18), and this risk was increased in women remaining nulligravid after using clomiphene citrate (HR 2.49, 95% CI 1.30 to 4.78) versus multiparous women (HR 1.52, 95% CI 0.67 to 3.42) (very low-certainty evidence). The slight increase in ovarian cancer risk among women having between one and three cycles of in vitro fertilisation (IVF) was reported, but this was not clinically significant (P = 0.18). There was no increase in risk of invasive ovarian cancer after use of infertility drugs in women with the BRCA mutation according to one cohort and one case-control study. The certainty of evidence as assessed using GRADE was very low.For borderline ovarian tumours, one cohort study reported increased risk in exposed women with an SIR of 3.61 (95% CI 1.45 to 7.44), and this risk was greater after treatment with clomiphene citrate (SIR 7.47, 95% CI 1.54 to 21.83) based on 12 cases. In another cohort study, the risk of a borderline ovarian tumour was increased, with an HR of 4.23 (95% CI 1.25 to 14.33), for subfertile women treated with IVF compared with a non-IVF-treated group with more than one year of follow-up. A large cohort reported increased risk of borderline ovarian tumours, with HR of 2.46 (95% CI 1.20 to 5.04), and this was based on 17 cases. A significant increase in serous borderline ovarian tumours was reported in one cohort study after the use of progesterone for more than four cycles (risk ratio (RR) 2.63, 95% CI 1.04 to 6.64). A case-control study reported increased risk after clomiphene citrate was taken, with an SIR of 2.5 (95% CI 1.3 to 4.5) based on 11 cases, and another reported an increase especially after human menopausal gonadotrophin was taken (odds ratio (OR) 9.38, 95% CI 1.66 to 52.08). Another study estimated an increased risk of borderline ovarian tumour, but this estimation was based on four cases with no control reporting use of fertility drugs. The certainty of evidence as assessed using GRADE was very low.However, although some studies suggested a slight increase in risks of ovarian cancer and borderline ovarian tumour, none provided moderate- or high-certainty evidence, as summarised in the GRADE tables.

AUTHORS' CONCLUSIONS

Since the last version of this review, only a few new relevant studies have provided additional findings with supporting evidence to suggest that infertility drugs may increase the risk of ovarian cancer slightly in subfertile women treated with infertility drugs when compared to the general population or to subfertile women not treated. The risk is slightly higher in nulliparous than in multiparous women treated with infertility drugs, and for borderline ovarian tumours. However, few studies have been conducted, the number of cancers is very small, and information on the dose or type of fertility drugs used is insufficient.

[Impact of gonadotropins in women suffering from cancer]

The role of gonadotropins in the genesis of malignant diseases, in particular gynecologic cancers, is still controversial. The production of ovarian steroids, as a consequence of FSH and LH actions, may constitute a bias to draw reliable conclusions. Over the past decades, the use of exogenous gonadotropins has markedly increased in cancer patients, candidates for fertility preservation, and in survivors facing infertility as a consequence of gonadotoxic treatments. In gynecologic cancers, high serum estradiol levels may be problematic and can therefore be overcome by specific protocols of ovarian stimulation. However, exogenous gonadotropin administration in cancer patients should systematically be included in a multidisciplinary approach. The present article discusses the possible role of gonadotropins as tumorigenic factors and the use of exogenous gonadotropins in females suffering from cancer.

[Infertility and breast cancer: Is there a link? Updated review of the literature and meta-analysis]

The objective of this review was to assess the level of risk of breast cancer of patients consulting for infertility.

METHODS

Studies of cohorts and case-control were extracted from the Pubmed database from January 2000 until May 2015 through the following keywords: "infertility"; "endometriosis"; "polycystic ovary syndrome"; "breast cancer", "cancer risk". Eleven publications were finally selected after exclusion of publications dealing with infertility after breast cancer. Our meta-analysis, involving 10 of these publications, was performed using Review Manager software, Cochrane Collaboration, 2014. The results were calculated by etiology of infertility, polycystic ovary syndrome (PCOS) and endometriosis, as well as globally.

RESULTS

The analysis of these published epidemiological studies confirms that infertility is not a breast cancer risk factor, but the results are contradictory. Three studies have shown a significantly increased risk of breast cancer in a population of infertile women, while 7 others have not found this risk. These contradictions are due to the heterogeneity of the studies, the included populations, the follow-up periods and confounding factors. Our meta-analysis of the selected studies has not identified a significant association between infertility and breast cancer risk (1.05; 95% CI [0.96-1.16]). A subgroup analysis on endometriosis and PCOS showed no significant association either, with an OR of 1.02 (95% CI [0.87-1.19]) and 1.19 (95% CI [0.93-1.51]), respectively.

CONCLUSION

Infertility is not an identified risk factor for breast cancer. A message reassuring about a possible risk of infertility-related breast cancer should be given to these patients. Infertility is therefore not an indication of increased breast surveillance.

Infertility etiologies are genetically and clinically linked with other diseases in single meta-diseases

The present review aims to ascertain whether different infertility etiologies share particular genes and/or molecular pathways with other pathologies and are associated with distinct and particular risks of later-life morbidity and mortality. In order to reach this aim, we use two different sources of information: (1) a public web server named DiseaseConnect ( http://disease-connect.org ) focused on the analysis of common genes and molecular mechanisms shared by diseases by integrating comprehensive omics and literature data; and (2) a literature search directed to find clinical comorbid relationships of infertility etiologies with only those diseases appearing after infertility is manifested. This literature search is performed because DiseaseConnect web server does not discriminate between pathologies emerging before, concomitantly or after infertility is manifested. Data show that different infertility etiologies not only share particular genes and/or molecular pathways with other pathologies but they have distinct clinical relationships with other diseases appearing after infertility is manifested. In particular, (1) testicular and high-grade prostate cancer in male infertility; (2) non-fatal stroke and endometrial cancer, and likely non-fatal coronary heart disease and ovarian cancer in polycystic ovary syndrome; (3) osteoporosis, psychosexual dysfunction, mood disorders and dementia in premature ovarian failure; (4) breast and ovarian cancer in carriers of BRCA1/2 mutations in diminished ovarian reserve; (5) clear cell and endometrioid histologic subtypes of invasive ovarian cancer, and likely low-grade serous invasive ovarian cancer, melanoma and non-Hodgkin lymphoma in endometriosis; and (6) endometrial and ovarian cancer in idiopathic infertility. The present data endorse the principle that the occurrence of a disease (in our case infertility) is non-random in the population and suggest that different infertility etiologies are genetically and clinically linked with other diseases in single meta-diseases. This finding opens new insights for clinicians and reproductive biologists to treat infertility problems using a phenomic approach instead of considering infertility as an isolated and exclusive disease of the reproductive system/hypothalamic-pituitary-gonadal axis. In agreement with a previous validation analysis of the utility of DiseaseConnect web server, the present study does not show a univocal correspondence between common gene expression and clinical comorbid relationship. Further work is needed to untangle the potential genetic, epigenetic and phenotypic relationships that may be present among different infertility etiologies, morbid conditions and physical/cognitive traits.

Does ovarian stimulation for IVF increase gynaecological cancer risk? A systematic review and meta-analysis

The aim of this study was to evaluate whether ovarian stimulation for IVF increases the risk of gynaecological cancer, including ovarian, endometrial, cervical and breast cancers, as an independent risk factor. A systematic review and meta-analysis was conducted. Clinical trials that examined the association between ovarian stimulation for IVF and gynaecologic cancers were included. The outcomes of interest were incidence rate of gynaecologic cancers. Twelve cohort studies with 178,396 women exposed to IVF were included; 10 studies were used to analyse ovarian (167,640 women) and breast (151,702 women) cancers, and six studies were identified in the analysis of endometrial (116,672 women) and cervical cancer (114,799 women). Among these studies, 175 ovarian, 48 endometrial, 502 cervical and 866 cases of breast cancer were reported. The meta-analysis found no significant association between ovarian stimulation for IVF and increased ovarian, endometrial, cervical and breast cancer risk (odds ratio [OR] 1.06, 95% confidence interval [CI] 0.85 to 1.32; OR 0.97, 95% CI 0.58 to 1.63; OR 0.43, 95% CI 0.30 to 0.60; OR 0.69, 95% CI 0.63 to 0.76, respectively). Ovarian stimulation for IVF, therefore, does not increase the gynaecologic cancer risk, whether hormone-dependent endometrial and breast cancer or non-hormone-dependent ovarian and cervical cancer.

Risk of ovarian cancer in women treated with ovarian stimulating drugs for infertility

BACKGROUND

The use of assisted reproductive techniques is increasing, but the possible link between fertility drugs and ovarian cancer remains controversial.

OBJECTIVES

To evaluate the risk of ovarian cancer in women treated with ovulation stimulating drugs for subfertility.

SEARCH METHODS

We searched for published and unpublished observational studies from 1990 to February 2013. The following databases were used: the Cochrane Gynaecological Cancer Collaborative Review Group's Trial Register, Cochrane Central Register of Controlled Trials (CENTRAL) 2013, Issue 1, MEDLINE (to February week 4 2013), EMBASE (to 2013 week 09) and databases of conference abstracts. We also scanned reference lists of retrieved articles. The search was not restricted by language of publication.

SELECTION CRITERIA

We searched for randomised controlled trials (RCTs) and non-randomised studies, and case series including more than 30 participants, reporting on women with exposure to ovarian stimulating drugs for treatment of subfertility and histologically confirmed borderline or invasive ovarian cancer.

DATA COLLECTION AND ANALYSIS

At least two review authors independently conducted eligibility and 'Risk of bias' assessment, and extracted data. We grouped studies based on the fertility drug used for two outcomes: borderline ovarian tumours and invasive ovarian cancer. We expressed findings as adjusted odds ratio (OR), risk ratio (RR), hazard ratio (HR) or crude OR if adjusted values were not reported and standardised incidence ratio (SIR) where reported. We conducted no meta-analyses due to expected methodological and clinical heterogeneity.

MAIN RESULTS

We included 11 case-control studies and 14 cohort studies, which included a total of 182,972 women.Seven cohort studies showed no evidence of an increased risk of invasive ovarian cancer in subfertile women treated with any drug compared with untreated subfertile women. Seven case-control studies showed no evidence of an increased risk, compared with control women of a similar age. Two cohort studies reported an increased incidence of invasive ovarian cancer in subfertile women treated with any fertility drug compared with the general population. One of these reported a SIR of 5.0 (95% confidence interval (CI) 1.0 to 15), based on three cancer cases, and a decreased risk when cancer cases diagnosed within one year of treatment were excluded from the analysis(SIR 1.67, 95% CI 0.02 to 9.27). The other cohort study reported an OR of 2.09 (95% CI 1.39 to 3.12), based on 26 cases.For borderline ovarian tumours, exposure to any fertility drug was associated with a two to three-fold increased risk in two case-control studies. One case-control study reported an OR of 28 (95% CI 1.5 to 516), which was based on only four cases. In one cohort study, there was more than a two-fold increase in the incidence of borderline tumours compared with the general population (SIR 2.6, 95% CI 1.4 to 4.6) and in another the risk of a borderline ovarian tumour was HR 4.23 (95% CI 1.25 to 14.33) for subfertile women treated with in vitro fertilisation (IVF) compared with a non-IVF treated group with more than one year of follow-up.There was no evidence of an increased risk in women exposed to clomiphene alone or clomiphene plus gonadotrophin, compared with unexposed women. One case-control study reported an increased risk in users of human menopausal gonadotrophin (HMG)(OR 9.4, 95% CI 1.7 to 52). However, this estimate is based on only six cases with a history of HMG use.

AUTHORS' CONCLUSIONS

We found no convincing evidence of an increase in the risk of invasive ovarian tumours with fertility drug treatment. There may be an increased risk of borderline ovarian tumours in subfertile women treated with IVF. Studies showing an increase in the risk of ovarian cancer had a high overall risk of bias, due to retrospective study design, lack of accounting for potential confounding and estimates based on a small number of cases. More studies at low risk of bias are needed.

IVF and breast cancer: a systematic review and meta-analysis

BACKGROUND

The effects of controlled ovarian hyperstimulation (COH) for IVF in terms of breast cancer risk remain controversial, despite the hormone-dependent nature of the latter.

METHODS

Eligible studies up to 15 February 2013 were identified and pooled effect estimates for relative risk (RR) were calculated separately for the investigations using the general population and those using infertile women, as a reference group. Fixed- or random-effects models were implemented and subgroup analyses were performed, as appropriate.

RESULTS

Eight cohort studies were synthesized, yielding a total cohort size of 1,554,332 women among whom 14,961 incident breast cancer cases occurred, encompassing 576 incident breast cancer cases among women exposed to IVF. No significant association between IVF and breast cancer was observed either in the group of studies treating the general population (RR = 0.91, 95% confidence interval (CI): 0.74-1.11) or infertile women (RR = 1.02, 95% CI: 0.88-1.18), as a reference group. Of note were the marginal associations, protective for pregnant and/or parous women after IVF (pooled effect estimate = 0.86, 95% CI: 0.73-1.01) and adverse for women <30 years at first IVF treatment (pooled effect estimate = 1.64, 95% CI: 0.96-2.80).

CONCLUSIONS

At present, COH for IVF does not seem to impart increased breast cancer risk. Longer follow-up periods, comparisons versus infertile women, subgroup analyses aiming to trace vulnerable subgroups, adjustment for various confounders and larger informative data sets are needed before conclusive statements for the safety of the procedure are reached.

[Cancer, fertility preservation and gonadotropins]

The recent emergence of oncofertility raises the question of ovarian stimulation and its risks when performed for oocyte or/and embryo cryopreservation in a fertility preservation program. The relation between ovarian stimulation and cancer has been marked by the possible direct or indirect tumorigenic role for pituitary gonadotrophins in the tumorogenesis. Although the growth of many gonadal and extragonadal tumors is stimulated by gonadal sex hormones, whose production is regulated by gonadotrophins, there is still a lack of data to consider FSH and LH as tumor promoters. The purpose of this brief review is to present on one hand, the questions raised by the administration of exogenous gonadotrophins in cancer patients and on the other, to evaluate both experimental and clinical data about the possible relation between gonadotrophins and tumorogenesis.

Autoantibodies to mesothelin in infertility

BACKGROUND

According to extensive epidemiologic data, infertility is associated with increased ovarian cancer risk. Previous studies showed that both women with infertility and those with ovarian cancer have autoantibodies to ovarian antigens. The objective was to determine if women with infertility have antibodies to mesothelin, a well-characterized ovarian cancer antigen.

METHODS

Sera were obtained from women with infertility (n = 109), ovarian cancer (n = 28), benign ovarian tumors or cysts (n = 24), and from healthy women (n = 152). Infertility included those with a risk for ovarian cancer; endometriosis (n = 23), ovulatory dysfunction (n = 17), premature ovarian failure (POF; n = 25) and unexplained infertility (n = 44). Sera were assayed for mesothelin antibodies and for circulating mesothelin antigen by immunoassay and compared with assay control sera (n = 16) to determine a positive result.

RESULTS

Mesothelin antibodies were significantly more frequent in women with prematurely reduced ovarian function including ovulatory dysfunction (59%), ovarian failure (44%) and unexplained infertility (25%) compared with controls. In contrast, women with endometriosis, who also have a high risk for ovarian cancer, did not have mesothelin antibodies. Serum levels of mesothelin were rarely elevated in women with infertility but were high in most patients with ovarian cancer.

CONCLUSIONS AND IMPACT

We show for the first time that antibodies to mesothelin, a well-characterized ovarian cancer antigen, occur in some women with epidemiologic risk for ovarian cancer. The results suggest it may be possible to identify which women with infertility have ovarian cancer risk.

The effects of parity, breastfeeding, and infertility treatment on the risk of hereditary breast and ovarian cancer: a review

Knowledge of the potential association of parity, breastfeeding, and infertility treatment on breast and ovarian cancer risk for BRCA1 and BRCA2 mutation carriers is important and should be a crucial part of genetic counseling. The discussion of parity and clinical management of infertility in these women is complex, and patient preferences should be considered. Ideally, these preferences should be informed by accurate information on the risks and benefits of the interventions considered. However, this important subject has been investigated in a relatively small number of studies, thus, the existing data remain somewhat limited, and the estimated risk of cancer in BRCA mutation carriers is imprecise.

Breast cancer incidence after hormonal infertility treatment in Sweden: a cohort study

OBJECTIVE

To assess the impact of infertility treatment with causes of infertility on incidence of breast cancer.

STUDY DESIGN

Historical prospective cohort study of 1135 women attending major university clinics for treatment of infertility in Sweden, 1961-1976. Women were classified as users of clomiphene citrate or gonadotropins, or a combination of both therapies. Standardized incidence ratios were calculated to estimate relative risk of breast cancer.

RESULTS

We observed 54 cases of breast cancer during 1961-2004, which did not significantly exceed those expected. Users of high-dose clomiphene citrate had an almost 2-fold increased risk (standardized incidence ratio, 1.90; 95% confidence interval, 1.08-3.35). This association was more pronounced among women referred for nonovulatory factors, with 3-fold increased risk (standardized incidence ratio, 3.00; 95% confidence interval, 1.35-6.67).

CONCLUSION

No overall increased risk for breast cancer was shown with infertility treatment. Women with nonovulatory causes treated with high-dose clomiphene citrate therapy may have an elevated risk for breast cancer.

Fertility drugs and risk of ovarian cancer: dispelling the myth

PURPOSE OF REVIEW

Worldwide 50-80 million people suffer from infertility. Assisted reproductive technology has provided a way of overcoming infertility and childlessness. The current article will focus on data linking infertility and its treatment to ovarian cancer.

RECENT FINDINGS

Ovarian cancer risks associated with fertility drug treatment are encouraging, but not decisive. In view of the limited ability to evaluate drug effects on borderline tumors, given their rare occurrence, studies involving patient reports of prior drug exposures have noted an elevated risk of borderline tumors associated with fertility drugs. Nevertheless, the risk of invasive ovarian cancer appears to be restricted to those women who remain childless despite the infertility treatment.

SUMMARY

As long as doubt persists, it might be advisable to reflect on a few clinical recommendations: identify high-risk infertile patients for ovarian cancer, investigate preexisting cancer before fertility treatment, inform patients regarding potential risks, obtain an informed consent, avoid exposure to long periods of ovulation induction cycles that are given before patients are referred for in-vitro fertilization and embryo transfer for women at greater risk and monitor women who have been treated with these drugs, especially those who failed to conceive, regularly and thoroughly.

Risk of breast cancer and gynecologic cancers in a large population of nearly 50,000 infertile Danish women

Infertility is considered to influence the risk of breast cancer and gynecologic cancers. To assess this association, the authors used data from a large cohort of 54,362 women with a diagnosis of infertility who were referred to Danish fertility clinics between 1963 and 1998. Through 2003, 1,975 cancers were identified by linkage to the Danish Cancer Registry. Cancer risk was assessed through standardized incidence ratios (SIRs) and corresponding 95% confidence intervals, using general and parity-specific cancer incidence rates in the general population of Denmark as a reference. After adjustment for parity status, significantly increased SIRs were observed for breast (SIR = 1.08, 95% confidence interval: 1.01, 1.16) and ovarian (SIR = 1.46, 95% confidence interval: 1.24, 1.71) cancer. The risk of breast cancer increased with follow-up time. Similar risk patterns were observed for the different histologic types of breast cancer and all nonmucinous types of ovarian cancer, whereas the risk of mucinous ovarian cancers seemed not to be increased. These data thus suggest higher risks of breast and ovarian cancer among infertile women. However, since these results could not distinguish the effects of underlying infertility from the effects of fertility treatment, additional studies are needed to disentangle the effects of these two factors.

Infertility, treatment of infertility, and the risk of breast cancer among women with BRCA1 and BRCA2 mutations: a case-control study

BACKGROUND

Women with a breast cancer susceptibility gene 1 (BRCA1) or breast cancer susceptibility gene 2 (BRCA2) mutation are at increased risk for developing breast and ovarian cancer. Various reproductive and hormonal factors have been shown to modify the risk of breast cancer. These studies suggest that estrogen exposure and deprivation are important in the etiology of hereditary cancer. Many patients are interested in the possibility of an adverse effect of fertility treatment on breast cancer risk. It is important to evaluate whether or not infertility per se or exposure to fertility medications increase the risk of breast cancer in genetically predisposed women.

METHODS

We conducted a matched case-control study of 1,380 pairs of women with a BRCA1 or BRCA2 mutation to determine if a history of infertility, the use of fertility medications, or undergoing in vitro fertilization (IVF) were associated with and increased the risk of breast cancer.

RESULTS

Sixteen percent of the study subjects reported having experienced a fertility problem and 4% had used a fertility medication. Women who had used a fertility medication were not at significantly increased risk of breast cancer (odds ratio [OR] = 1.21; 95% confidence interval [CI] = 0.81-1.82) compared to non-users. Furthermore, there was no risk associated with a history of use of a fertility medication when the subjects were stratified by parity: (OR = 1.29; 95% CI = 0.83-2.01 for nulliparous women and OR = 0.81; 95% CI = 0.30-2.22 for parous women).

CONCLUSIONS

The results of this study suggest that the use of fertility medications does not adversely affect the risk of breast cancer among BRCA mutation carriers. Given the small sizes of the exposed subgroups, these findings should be interpreted with caution and confirmatory studies are required.

The possible association between IVF and breast cancer incidence

BACKGROUND

The possible association between ovulation-inducing drugs and breast cancer development has been debated. Our aim was to evaluate the incidence of breast cancer in a cohort of women exposed to in vitro fertilization (IVF).

METHODS

A retrospective cohort analysis was performed by linkage of the computerized database of all women treated at the IVF Unit at Assaf Harofeh Medical Center between 1986 and 2003, and the Israeli National Cancer Registry. The standardized incidence ratio (SIR) was computed as the ratio between the observed number of breast cancer cases and the expected cases, adjusted for age and continent of birth, in the general population. Tumor characteristics of the IVF patients were studied by reviewing original medical records.

RESULTS

35 breast carcinomas were diagnosed among 3,375 IVF-treated women, compared to 24.8 cases expected (SIR = 1.4; 95% CI 0.98-1.96). Age >or=40 years at IVF treatment (SIR = 1.9; 95% CI 0.97-3.30), hormonal infertility (SIR = 3.1; 95% CI 0.99-7.22), and >or=4 IVF cycles (SIR = 2.0; 95% CI 1.15-3.27) were found to be risk factors to develop breast cancer compared to the general population. Multivariate analysis revealed that women who underwent >or=4 IVF cycles compared to those with one to three cycles were at risk to develop breast cancer, although not significantly (SIR = 1.9; 95% CI 0.95-3.81). Of IVF-treated women 85% had ER(+) tumors and 29% had positive family history.

CONCLUSIONS

A possible association between IVF therapy and breast cancer development was demonstrated, especially in women >or=40 years of age. These preliminary findings need to be replicated in other cohort studies.

Ovulation induction treatment and risk of borderline ovarian tumors

AIM

Research has suggested an association between the use of ovulation induction drugs and the risk of ovarian cancer. It has also been proposed that there may be pre-cancerous alterations in the ovary which themselves are the cause of infertility. The aim of the present study was to evaluate the relationship between the use of ovulation induction drugs and the appearance of borderline ovarian tumors.

MATERIAL AND METHODS

This was a case-control study in which the study group comprised 42 women with a borderline ovarian tumor and the control group comprised 257 women with benign ovarian pathology.

RESULTS

No differences were found between the borderline tumor and control groups (14.3% vs. 27.2%, respectively) in terms of infertility history. Nor were there any differences between the groups with respect to the type of drug used, whether clomiphene citrate (9.5% vs. 6.2%, respectively) or gonadotropins (7.1% vs. 10.1%, respectively). Analysis in terms of the number of cycles administered also failed to reveal any differences. The mean number of cycles with clomiphene citrate/gonadotropins was 2.50 +/- 1.00 and 3.00 +/- 2.64 in the borderline tumor group and 2.44 +/- 1.75 and 3.27 +/- 2.25 in the control group.

CONCLUSIONS

Our series produced no evidence that ovulation induction treatment predisposes women to the development of borderline ovarian tumors.

Safety of drugs used in assisted reproduction techniques

Infertility may affect one in six couples; however, the development of the assisted reproduction technique (ART) created the opportunity for a large proportion of the infertile population to bear children. Pharmacological agents are routinely used in ART, and new ones are introduced regularly, with the aim of retrieving multiple oocytes to increase the prospect of pregnancy. The combinations of drugs that are used have specific adverse effects, but it is mostly the combined action of more than one agent that causes the greatest concern. The matter is complicated by the suspicion that some techniques in ART, for example intracytoplasmic sperm injection for severe male infertility problems (including azoospermia), may also contribute to the increase in adverse effects, especially congenital malformation. Gonadotropin releasing hormone (GnRH) agonists are widely used in controlled ovarian hyperstimulation. It may give rise to a short period of estradiol withdrawal symptoms and it may also lead to luteal phase deficiency. Similarly GnRHa antagonists, which have been recently introduced to control ovarian hyperstimulation, can lead to luteal phase deficiency and may cause some local injection site reactions. The more pure form of gonadotropin leads to less local injection site reactions and their main adverse effects are associated with the consequences of multiple ovulations. It has been proposed that gonadotropins may be a factor in the increasing risk of ovarian cancer and possibly breast cancer, but this has not been substantiated. Prion infection is another potential hazard, although no cases have been reported. Ovarian hyperstimulation syndrome is a well recognised complication of controlled ovarian hyperstimulation in ART. It is usually a result of recruitment of a large number of ovarian follicles. Efforts to minimise the incidence of this syndrome and its severity are now well developed. Congenital malformations are another possible adverse effect of fertility drugs, but it is more probable that the increase in congenital abnormality that is reported in ART is because of the population studied, i.e. patients already at high risk of congenital malformation, rather than the fertility drugs used or the technique employed. High order multiple pregnancy and its sequela is a well established complication of controlled ovarian hyperstimulation. This could be a result of multiple ovulations or more than one embryo replacement. Reducing the number of embryos transferred can reduce this more serious adverse effect for expectant mothers and for children conceived from ART.

Induction of ovulation and ovarian cancer: a critical review of the literature

OBJECTIVE

To critically examine the possible association between ovulation-inducing drugs and ovarian cancer.

DESIGN

Medline literature review and cross-reference of published data.

RESULTS(S)

The studies that have adjusted for the effects of confounding factors such as duration of oral contraceptive use and number of pregnancies have noted an increased risk of ovarian cancer among infertile women who remain childless despite long periods of unprotected intercourse. Whether such women are at risk due to the primary basis for their infertility or factors such as ovulation-inducing drugs, has been the subject of several studies. Overall, the findings on ovarian cancer (especially invasive epithelial and non-epithelial) risk associated with fertility drug treatment are reassuring. However, a stronger association between fertility drug use and borderline tumors of the ovary has been observed.

CONCLUSION(S)

Despite the overall reassuring findings of the available studies, there is a need for well-designed clinical trials to understand the possible carcinogenic effects of the ovulation-inducing drugs.

Is birth history the key to highly educated women's higher breast cancer mortality? A follow-up study of 500,000 women aged 35-54

A positive relationship has been found between high levels of education and breast cancer mortality. The aim of our study is to determine if the educational gradient in breast cancer mortality persists after adjustment for reproductive history. Register data including the total adult population in Norway were used. A total of 512,353 Norwegian women 35-54 years of age at the Norwegian Census in 1990 were followed with respect to breast cancer deaths until December 31, 2001. The analysis included 2,052 breast cancer deaths in 5.6 million person years. Educational differences in breast cancer mortality were analysed using Cox regression. The age adjusted relative risk of dying from breast cancer for women with >12 years of education compared to women with <10 years was 1.25 (95% confidence limits [CI] = 1.10-1.41). Adjustment for age at first birth with nulliparous as reference category reduced this difference to 1.08 (95% CI = 0.95-1.23). For parous women, age at first birth explained all the educational difference in breast cancer mortality. Among nulliparous women there was a larger positive educational gradient in breast cancer mortality than among parous women (relative risk [RR] = 1.57, 95% CI = 1.15-2.13), indicating that there were differences in other confounders than birth history among the childless.

Association between fertility drugs and gynecologic cancers, breast cancer, and childhood cancers

Ovulation-inducing drugs have been widely used for various types of infertility since the beginning of 1960s and their use increases day by day parallel to the success achieved in fertility treatment. However, the researches performed in the last two decades have begun to discuss about the safety of these drugs and the risks associated with their use. Especially, the potential neoplastic effects of these drugs are increasingly questioned. The studies have discussed whether there is an association between the exposure to ovulation-inducing drugs and the incidence of various cancers. Moreover, several studies have been performed to reveal whether there is an increased risk of childhood cancers in children conceived after fertility treatment. The point we reached through the available data is that the risk of breast, uterine and invasive ovarian cancers is not increased, but the risk of borderline ovarian tumors might increase after such a therapy. The risk of cancer has been found similar for children conceived after fertility treatment and those conceived naturally. It should also be kept in mind that cancers are overdiagnosed in infertile women population because of the close medical surveillance, which may also contribute to the early detection of cancers. Although it is still early to state the last words on this topic, the possible association should be addressed when obtaining an informed consent before starting treatment.

[Genomic instability and male infertility]

Knowledge of the human genome has opened the genomic era. The genome instability, its causes and the possible consequences especially about fertility start to be understood. This instability can be observed on chromosome structure but also on genes. Different chromosomes rearrangements involved in infertility including translocations and Y chromosome deletions are described. The Y chromosome is a model of instability, and this instability is the source of its evolution. All those rearrangements are the results of illegitimate recombinations between homologous sequences. On genes we find punctual and dynamic mutations, polymorphisms and epigenetic abnormalities. They all are the results of ADN replication mistakes not corrected by the cellular machine. This machinery is the guardian of the genome integrity and in case of abnormality the programmed cellular death is induced. The knowledge of all these instability mechanisms is essential to appreciate the risk for the offspring after intracytoplasmic sperm injection. Indeed we go round physiological barriers without a complete understanding of the mechanisms involved. Thus, this is an important challenge for research teams but also for all assisted reproduction centers, dealing with ART. Genome is unstable - the very basis of its evolution. But this is also the cause of mistakes with pathological consequences like infertility and mental retardation.

Successful Infertility Treatment in a Cancer Patient with a Significant Personal and Family History of Cancer

BACKGROUND

Infertility can be a devastating problem for a couple desperate to conceive. Unfortunately, these same women with infertility also bear the burden of an increased risk of ovarian and breast cancer. We present a case of a woman with infertility who persevered despite a personal and family history of cancer to achieve her goal of having a family.

CASE

The patient's father had died of breast cancer at an early age. The patient had been unsuccessfully treated for infertility elsewhere before transferring to our institution. A diagnostic laparoscopy revealed an early ovarian cancer treated by oophorectomy only.

RESULTS

After a period of observation, infertility treatment was resumed, leading to the successful cesarean delivery of triplets. Although recurrent ovarian cancer was diagnosed at delivery, the patient remains disease free, with three healthy children, 4 years after optimal tumor reductive surgery for stage IC low malignant potential ovarian cancer.

CONCLUSIONS

Infertility patients with significant cancer issues may achieve a term delivery and remain disease free for a meaningful length of time with the assistance of their physicians.