Chemotherapy-Induced Amenorrhea - An Update

The oestrous cycle stage affects mammary tumour sensitivity to chemotherapy

The response of breast cancer to neoadjuvant chemotherapy (NAC) varies substantially, even when tumours belong to the same molecular or histological subtype1. Here we identify the oestrous cycle as an important contributor to this heterogeneity. In three mouse models of breast cancer, we show reduced responses to NAC when treatment is initiated during the dioestrus stage, when compared with initiation during the oestrus stage. Similar findings were observed in retrospective premenopausal cohorts of human patients. Mechanistically, the dioestrus stage exhibits systemic and localized changes, including (1) an increased number of cells undergoing epithelial-to-mesenchymal transition linked to chemoresistance2-4 and (2) decreased tumour vessel diameter, suggesting potential constraints to drug sensitivity and delivery. In addition, an elevated presence of macrophages, previously associated with chemoresistance induction5, characterizes the dioestrus phase. Whereas NAC disrupts the oestrous cycle, this elevated macrophage prevalence persists and depletion of macrophages mitigates the reduced therapy response observed when initiating treatment during dioestrus. Our data collectively demonstrate the oestrous cycle as a crucial infradian rhythm determining chemosensitivity, warranting future clinical studies to exploit optimal treatment initiation timing for enhanced chemotherapy outcomes.

The role of oxidative stress in ovarian aging: a review

Ovarian aging refers to the process by which ovarian function declines until eventual failure. The pathogenesis of ovarian aging is complex and diverse; oxidative stress (OS) is considered to be a key factor. This review focuses on the fact that OS status accelerates the ovarian aging process by promoting apoptosis, inflammation, mitochondrial damage, telomere shortening and biomacromolecular damage. Current evidence suggests that aging, smoking, high-sugar diets, pressure, superovulation, chemotherapeutic agents and industrial pollutants can be factors that accelerate ovarian aging by exacerbating OS status. In addition, we review the role of nuclear factor E2-related factor 2 (Nrf2), Sirtuin (Sirt), mitogen-activated protein kinase (MAPK), protein kinase B (AKT), Forkhead box O (FoxO) and Klotho signaling pathways during the process of ovarian aging. We also explore the role of antioxidant therapies such as melatonin, vitamins, stem cell therapies, antioxidant monomers and Traditional Chinese Medicine (TCM), and investigate the roles of these supplements with respect to the reduction of OS and the improvement of ovarian function. This review provides a rationale for antioxidant therapy to improve ovarian aging.

A prospective, observational study of chemotherapy-induced ovarian damage on follicular reserve and maturation

BACKGROUND

Chemotherapy negatively affects gonadal function, often resulting in premature ovarian failure (POF) due to ovarian reserve depletion. Mechanisms of gonadotoxicity, such as primordial follicle overactivation and "burnout", remain to be established. Ovarian tissue cryopreservation (OTC) before treatment plays an important role in safeguarding fertility.

METHODS

This is a prospective observational study that aims to evaluate the feasibility of OTC after chemotherapeutic treatment initiation. Patients were divided into 2 groups depending on whether they received chemotherapy before the harvesting procedure (Group 1) or not (Group 2). The main outcomes of this study are serum anti-Mullerian hormone (AMH) levels and histological follicular counts on ovarian tissue biopsies.

RESULTS

Between 2012 and 2020, 79 patients underwent OTC at our Hospital. Follicular counts from the ovarian biopsies of 30 post-pubertal patients and respective serum AMH levels were included in the analysis. AMH levels did not significantly differ between the 2 groups (P = 0.70) as well as the number of primordial follicles (P = 0.73). Ovarian biopsies of patients from Group 1 showed a higher number of primary follicles (P = 0.04) and atretic follicles (P = 0.05) with respect to Group 2.

CONCLUSIONS

In conclusion, OTC appears to be feasible even after the start of chemotherapeutic treatment, since in treated patients, the main ovarian reserve indicators (number of primordial follicles and serum AMH levels) were not significantly reduced compared to untreated patients. The "burnout" theory of chemotherapeutic damage to the ovary seems to be supported by the higher number of primary follicles found in the ovaries of patients who received chemotherapy before OTC.

Fertility and breast cancer: A literature review of counseling, preservation options and outcomes

Fertility preservation is an important issue in breast cancer patients undergoing oncological treatment. Fertility counseling is a crucial need given the physical and psychological stress experienced by patients. Cryopreservation of mature oocytes is currently the standard fertility-preserving procedure. Other options such as ovarian tissue preservation or gonadal protection during chemotherapy are still experimental, but have proven effectiveness. Prompt referral to a fertility unit is highly recommended in order to ensure quality of care. In this article, we focus on the different strategies to preserve fertility in breast cancer patients, assessing also the safety of pregnancy and breastfeeding after cancer. A systemic literature review was performed for research articles published in English in PubMed, or as abstracts from the European Society for Medical Oncology (ESMO), San Antonio Breast Cancer Symposium (SABCS) and American Society of Clinical Oncology (ASCO) annual meetings, using the search terms "breast cancer" and "fertility".

Fertilitätserhalt bei Patienten in der Dermatoonkologie – Eine aktuelle Übersicht

Bei vielen Patienten, die an einem Malignom erkranken, ist die Familienplanung noch nicht abgeschlossen, sodass für den Erhalt des fertilen Potenzials Maßnahmen der Fertilitätsprotektion sinnvoll sind. Durch eine Polychemotherapie, unabhängig ob im neoadjuvanten oder adjuvanten Setting, Molekular- oder Immuntherapien kann es zu einer irreversiblen Schädigung der Follikel bzw. Spermatogenese kommen, was u. U. zu einer permanenten Infertilität führen kann. Abhängig von der verwendeten Therapie und der altersabhängigen Ovarialreserve der Frau muss das gonadotoxische Risiko als niedrig, mittel oder hoch eingeschätzt werden. Möglichkeiten des Fertilitäserhalts sind: a) die Kryokonservierung von fertilisierten oder unfertilisierten Oozyten. Hierbei werden nach ovarieller Hyperstimulation reife Oozyten mittels transvaginaler Follikelaspiration gewonnen und im Anschluss entweder unfertilisiert oder nach erfolgter IVF- oder ICSI-Behandlung kryokonserviert. Bei b) der Kryokonservierung von Ovarialgewebe wird mithilfe eines laparoskopischen Eingriffs etwa 50 % des Ovarkortex eines Ovars reseziert und kryokonserviert. Die Verwendung von c) GnRH-Agonisten als medikamentöse Therapieoption unternimmt den Versuch einer endokrinen Ovarialsuppression, um Oozyten, Granulosa- und Thekazellen vor dem zytotoxischen Einfluss der jeweiligen Therapie zu schützen. Bei männlichen Patienten können Spermien vor Therapiebeginn kryokonserviert werden.

Fertility Preservation in Female Patients with Breast Cancer - a Current Overview

Many premenopausal patients who develop breast cancer have not yet completed their family planning, so measures of fertility protection to preserve their fertile potential would be beneficial. Polychemotherapy causes irreversible damage to the ovarian follicles – irrespective of whether in a neoadjuvant or adjuvant setting – and this can sometimes result in permanent infertility. Depending on which cytostatic agents are used and on the age-related ovarian reserve of the woman, gonadotoxic risk must be classified as low, moderate or high. Options of fertility preservation include: a) cryopreservation of fertilised or unfertilised oocytes. After ovarian hyperstimulation, mature oocytes are retrieved by transvaginal follicle aspiration, after which they are cryopreserved, either unfertilised or on completion of IVF or ICSI treatment. During b) cryopreservation of ovarian tissue, about 50% of the ovarian cortex of one ovary is resected with the aid of a laparoscopic procedure and cryopreserved. The application of c) GnRH agonists as a medicinal therapy option is an attempt at endocrine ovarian suppression in order to protect oocytes, granulosa cells and theca cells from the cytotoxic effect of chemotherapy.