Fertility preservation, its effectiveness and its impact on disease status in pre-menopausal women with breast cancer: A systematic review and meta-analysis

INTRODUCTION

Preservation of reproductive function is a key concern for many premenopausal women with breast cancer, given the known gonadotoxic effects of treatments. The present systematic review aimed to investigate the effectiveness and safety of fertility preservation strategies in pre-menopausal women with breast cancer.

METHODS

Primary research assessing fertility preservation strategies of any type was identified. Markers of preservation of fertility including return of menstrual function, clinical pregnancy rates and live birth rates were selected as main outcome measures. An additional analysis of safety data was also performed.

RESULTS

Fertility preservation interventions were overall associated with higher fertility outcomes: with a pooled odds ratio 4.14 (95% CI 3.59-4.77) for any kind of fertility preservation intervention. This was seen both for return of menstruation and for clinical pregnancy rate, but not for live birth rates. Fertility preservation was associated with a reduced rate of disease recurrence (OR 0.63 (95% CI 0.49-0.81)), while there was no significant difference in disease free survival (OR 0.88 (95% CI 0.74-1.05)) or in overall survival (OR 0.9 (95% CI 0.74-1.10)) between the fertility preservation group and those who had not undergone fertility preservation.

CONCLUSION

Fertility preservation is both effective in preserving reproductive function, and safe with regard to disease recurrence, disease free survival and overall survival in premenopausal women with breast cancer.

Gonadotropin-Releasing Hormone Analogs for Gonadal Protection During Gonadotoxic Chemotherapy: A Systematic Review and Meta-Analysis

OBJECTIVE

A systematic review and meta-analysis was conducted to investigate whether gonadotropin-releasing hormone analogs (GnRHa) have a protective role in women treated with alkylating agents.

DATA SOURCES

Major databases (PubMED, EMBASE, Cochrane Central Register of Controlled Trials), systematic snowballing, and trial registries were screened from the inception dates until September 2017.

METHODS AND STUDY SELECTION

Comparative studies involving reproductive-aged women undergoing chemotherapy with or without coadministration of GnRHa were included. Spontaneous menstrual resumption was assessed as a main outcome. Statistical analyses were performed with STATA 14.2 statistical software. Effect estimates were presented as risk ratios (RR) with 95% confidence intervals (CIs).

RESULTS

The literature search yielded 25 436 citations and 84 papers were assessed in full text. Eighteen studies (11 randomized controlled trials [RCTs] and 7 cohort studies) published between 1987 and 2015 were included in the analysis, revealing a significant protective effect of GnRHa (n = 1043; RR:1.38; 95% CI: 1.18-1.63) although with high heterogeneity (I² = 83.3%). Subgroup analyses revealed a significant benefit of GnRHa cotreatment both in RCTs and in cohort studies. Statistical significance was found in all subgroups by the underlying disease, that is, hematological malignancies, autoimmune diseases, and breast cancer. Sensitivity analyses in GnRH agonist-treated patients, in patients younger than 40 years old, and in patients without supradiaphragmatic radiotherapy also revealed a significant benefit of GnRHa cotreatment.

CONCLUSION

Our results indicate that concurrent GnRHa administration is an effective method to decrease gonadotoxicity of alkylating agents. The presence of low-quality evidence favoring gonadoprotective effect requires a strong recommendation for offering GnRHa coadministration to young women who are to undergo gonadotoxic chemotherapy.

CAPSULE

The present systematic review and meta-analysis shows a significant gonadoprotective effect of gonadotropin-releasing hormone analogs in women treated with alkylating agents.