Endocrine therapy in the management of low-grade serous ovarian/peritoneal carcinoma: Mounting evidence for therelative efficacy of tamoxifen and aromatase inhibitors

Endocrine Maintenance Therapy in High-Grade Serous Ovarian Cancer: A Retrospective Off-Label Real-World Cohort Study

BACKGROUND

Endocrine therapy is the standard-of-care maintenance treatment for estrogen receptor (ER)-positive breast cancers and is increasingly used in low-grade serous ovarian cancer. However, its therapeutic role in the early maintenance setting for ER-positive high-grade serous ovarian cancer (HGSC) remains undefined.

METHODS

A retrospective analysis was conducted on clinicopathological data from patients with newly diagnosed ER-positive HGSC following completion of adjuvant chemotherapy. Patients received maintenance therapy either with or without the aromatase inhibitor letrozole, in addition to standard maintenance care. ER expression levels and the administration of letrozole were analyzed, along with outcome measures for the entire cohort, with stratification based on residual disease status.

RESULTS

A total of 102 patients with newly diagnosed HGSC were included in the analysis, with 64 (62.7%) receiving letrozole and 38 (37.3%) not receiving letrozole. The median ER expression was 70%, with higher expression observed in the letrozole group compared to the no letrozole group (77.5% vs. 60%). No significant correlation was found between ER expression status and therapy response (p = 0.295 and p = 0.176, respectively). Letrozole therapy was well tolerated with no major adverse effects reported. In the overall cohort, maintenance letrozole therapy did not confer a significant improvement in progression-free survival (median 20.56 months vs. 29.34 months, p = 0.53) or overall survival (OS) (median 79.48 months vs. 46.85 months, p = 0.71) over a median follow-up duration of 23.5 months. However, among patients with no residual disease, maintenance letrozole therapy was associated with a statistically significant improvement in OS compared to those not receiving letrozole (median 114 months vs. 46.9 months, p = 0.006).

CONCLUSIONS

Maintenance letrozole therapy appears to be a well-tolerated and potentially beneficial intervention in a subset of patients with ER-positive HGSC with no residual disease post-treatment. These findings highlight the need for further validation through prospective randomized trials to comprehensively assess the efficacy of endocrine therapy in this setting and its implications for patient quality of life.

The Megacomplex protects ER-alpha from degradation by Fulvestrant in epithelial ovarian cancer

Ovarian cancer, a significant contributor to cancer-related mortality, exhibits limited responsiveness to hormonal therapies targeting the estrogen receptor (ERα). This study aimed to elucidate the mechanisms behind ERα resistance to the therapeutic drug Fulvestrant (ICI182780 or ICI). Notably, compared to the cytoplasmic version, nuclear ERα was minimally degraded by ICI, suggesting a mechanism for drug resistance via the protective confines of the nuclear substructures. Of these substructures, we identified a 1.3 MDa Megacomplex comprising transcription factors ERα, FOXA1, and PITX1 using size exclusion chromatography (SEC) in the ovarian cancer cell line, PEO4. ChIP-seq revealed these factors colocalized at 6775 genomic positions representing sites of Megacomplex formation. Megacomplex ERα exhibited increased resistance to degradation by ICI compared to cytoplasmic and nuclear ERα. A small molecule inhibitor of active chromatin and super-enhancers, JQ1, in combination with ICI significantly enhanced ERα degradation from Megacomplex as revealed by SEC and ChIP-seq. Interestingly, this combination degraded both the cytoplasmic as well as nuclear ERα. Pathway enrichment analysis showed parallel results for RNA-seq gene sets following Estradiol, ICI, or ICI plus JQ1 treatments as those defined by Megacomplex binding identified through ChIP-seq. Furthermore, similar pathway enrichments were confirmed in mass-spec analysis of the Megacomplex macromolecule fractions after modulation by Estradiol or ICI. These findings implicate Megacomplex in ERα-driven ovarian cancer chromatin regulation. This combined treatment strategy exhibited superior inhibition of cell proliferation and viability. Therefore, by uncovering ERα's resistance within the Megacomplex, the combined ICI plus JQ1 treatment elucidates a novel drug treatment vulnerability.

Steroid metabolism and hormonal dynamics in normal and malignant ovaries

The ovaries are key steroid hormone production sites in post-pubertal females. However, current research on steroidogenic enzymes, endogenous hormone concentrations and their effects on healthy ovarian function and malignant development is limited. Here, we discuss the importance of steroid enzymes in normal and malignant ovaries, alongside hormone concentrations, receptor expression and action. Key enzymes include STS, 3β-HSD2, HSD17B1, ARK1C3, and aromatase, which influence ovarian steroidal action. Both androgen and oestrogen action, via their facilitating enzyme, drives ovarian follicle activation, development and maturation in healthy ovarian tissue. In ovarian cancer, some data suggest STS and oestrogen receptor α may be linked to aggressive forms, while various oestrogen-responsive factors may be involved in ovarian cancer metastasis. In contrast, androgen receptor expression and action vary across ovarian cancer subtypes. For future studies investigating steroidogenesis and steroidal activity in ovarian cancer, it is necessary to differentiate between disease subtypes for a comprehensive understanding.

British Gynaecological Cancer Society and British Menopause Society guidelines: Management of menopausal symptoms following treatment of gynaecological cancer

These guidelines have been developed jointly by the British Gynaecological Cancer Society and British Menopause Society to provide information for all healthcare professionals managing women treated for gynaecological cancer. Menopausal symptoms can have a significant impact on quality of life for women. Cancer therapies, including surgery, pelvic radiotherapy, chemotherapy and endocrine therapy, can all affect ovarian function. The benefits and risks of using hormone replacement therapy are considered by cancer type with guidance on the type of HRT and optimal time of commencement after cancer treatment. Vaginal estrogens can be very effective for improving urogenital symptoms and are safe for the majority of women, including those for whom systemic HRT is contraindicated with rare exceptions. Alternative options to HRT are reviewed including pharmacological and non-pharmacological approaches.

Ocular side effects of anticancer agents used in the treatment of gynecologic cancers

The treatment landscape of gynecologic cancers has expanded in recent years to include targeted and immune-based therapies. These therapies often have ocular side effects not seen with conventional chemotherapies, some of which can cause significant visual impairment if not recognized in a timely fashion. Clinicians must know how to appropriately identify, mitigate, and treat these ocular adverse events. Management often involves working with an interdisciplinary team of eye specialists, and it is important to know when to refer patients for specialized care. Proactive identification of eye specialists, especially in rural and community settings where access to care can be limited, may be necessary. Here, we discuss the management of common ocular toxicities seen with novel anticancer agents used to treat gynecologic cancers.

Contemporary primary treatment of women with stage II-IV low-grade serous ovarian/peritoneal cancer (LGSOC): Determinants of relapse and disease-free survival

OBJECTIVE

The purpose of the present study is to describe a cohort who received contemporary primary treatment for stage II-IV low-grade serous ovarian/peritoneal cancer (LGSOC), including patient characteristics and determinants of relapse and disease-free survival.

METHODS

The study included 99 patients: 1) with pathologically confirmed stage II-IV LGSOC of the ovary or peritoneum, 2) who underwent primary treatment consisting of cytoreductive surgery and either a) platinum/taxane chemotherapy followed by aromatase inhibitor maintenance therapy or b) aromatase inhibitor monotherapy, and 3) for whom there was availability of clinical data. Descriptive statistics were used to characterize clinicodemographic features. Subgroups were compared for PFS and OS. Multivariable Cox regression analyses were performed.

RESULTS

Median PFS for the entire cohort was 56.8 months (95% CI, 41.3-NE), and median OS was 130.7 months (95% CI, 115.0-146.4). Forty-nine of 99 (49.5%) patients have relapsed to date. For these 49 patients, median time from diagnosis to relapse was 29.6 months (95% CI, 24.6-33.1) (range, 5.4-69.1 months). Only 1/49 (2%) patients who relapsed did so >5 years from diagnosis. Fifty (50.0%) patients have not experienced disease progression or relapse. Median follow-up time for these 50 patients is 86.2 months (range, 25.3-169.0). Thirty-three of the 50 (66.0%) have been followed for >5 years from diagnosis. On regression analyses, factors associated with improved patient outcomes-either PFS, OS, or both-included no gross residual disease, normal serum CA 125 at diagnosis, primary peritoneal site, and presence of extensive psammomatous calcifications.

CONCLUSIONS

This is the first report to describe the clinicopathologic features and outcomes of women with stage II-IV LGSOC who received contemporary primary therapy.