Through the last three decades, the combination of paclitaxel and carboplatin remains the standard of care chemotherapy in newly diagnosed epithelial ovarian cancer (EOC). Based on a single trial, first-line maintenance therapy with angiogenesis inhibitor bevacizumab was approved in Europe and widely applied. In 2018, based on a second trial bevacizumab was approved for first-line maintenance in the United States. Despite complete remission upon chemotherapy, the majority of the patients recur. A large number of randomized trials were conducted to explore the optimal front-line therapy regimen, but neither dose-densing, nor adding of a third chemotherapy agent or intraperitoneal administration could improve overall survival (OS). Also implementation of hyperthermic intraperitoneal chemotherapy (HIPEC) or the neoadjuvant approach failed to improve OS. Recently, maintenance therapy with PARP inhibitors showed encouraging results in patients with BRCA1/2 mutation. Further trials with targeted therapies are ongoing. Here we review the achievements of front-line therapy in primary advanced EOC through the last three decades and discuss future treatment strategies.

The AGO-OVAR16 study was designed to test the efficacy, safety, and tolerability of pazopanib maintenance after first-line chemotherapy in patients with newly diagnosed advanced ovarian cancer (AOC). Nine hundred and forty patients with histologically confirmed AOC, International Federation of Gynecology and Obstetrics (FIGO) stage II-IV, were randomized in a 1:1 ratio to receive either 800 mg pazopanib once daily or placebo for up to 24 months, unless there was disease progression, toxicity, withdrawal of consent, or death. The primary endpoint (investigator-assessed progression-free survival [PFS]) was met and previously reported. The results of final analyses of overall survival (OS) are reported here. A third OS interim analysis showed futility and led to study closure and a final OS analysis after last patient last visit. At the time of the final OS analysis, 494 (89.7% of the planned 551) events had occurred. No difference was observed in OS between pazopanib and placebo. The hazard ratio (HR) was 0.960 (95% confidence interval [CI]: 0.805-1.145), and the median OS from randomization was 59.1 months in pazopanib and 64.0 months in placebo arms. For the East Asian patients, similar to the first three interim OS analyses, a numerical negative trend was observed favoring placebo (HR, 1.332; 95% CI: 0.863-2.054). Exploratory analyses showed a trend for a longer time to first subsequent anti-cancer therapy or death with pazopanib over placebo (HR, 0.829; 95% CI: 0.713-0.965), with a median estimate of 19.0 and 14.5 months, respectively. No new safety signals were observed. Although pazopanib prolonged PFS, this was not associated with improvement in median OS. ClinicalTrials.gov: NCT00866697.

The tumor suppressor miR-34 family is transcriptionally induced by p53. Clinical significance of the various miR-34 family members has not been studied in ovarian cancer. In 228 ovarian cancers and in 19 non-neoplastic fallopian tube samples we analysed miR-34 a/b/c expression in relation to clinicopathological characteristics and clinical outcome. We found significantly lower levels of miR-34 a/b/c in ovarian cancers as compared to control-tissues (P=0.002, P<0.001, P<0.001, respectively). Expression of miR-34 b/c revealed an inverse correlation with BRCA1/2 mRNA-expression (BRCA1: miR34 b/c P=0.002 each; BRCA2: miR-34 b/c P<0.001 each), the same was true for miR-34a and BRCA2 mRNA-expression (P<0.001). The miR-34 family expression was found to be significantly lower in type 2 in comparison to type 1 cancers (P<0.001) and in TP53-mutated compared with TP53-wild-type ovarian cancers (P<0.001, P=0.002, P=0.004, respectively). When low grade serous ovarian cancers were compared with high grade serous cancers the respective miR-34 a/b/c expression was 2.6-, 40.8- and 32.3-fold higher. The expression of each of the miR-34 family members was revealed to be of independent prognostic relevance regarding progression free survival (PFS); miR-34a: HR 0.6, P=0.033; miR-34b: HR 0.2, P=0.001 and miR-34c: HR 0.3, P=0.002, respectively). For overall survival (OS) independency of the prognostic value was confined to miR-34b (HR 0.4, P=0.016) and miR-34c (HR 0.6, P=0.049). The independency of the prognostic value of our identified thresholds was confirmed for PFS for miR-34c in a publicly available dataset (NCBI Gene Expression Omnibus GSE73582). Our findings suggest that downregulation of miR-34 family is a crucial part in ovarian cancer development. Low miR-34 levels are linked to a worse overall survival and progression free survival and may indicate a more aggressive disease.

Mutations in BRCA1 and BRCA2 are associated with better survival in ovarian cancer (OC) patients due to a better response to platinum-based chemotherapy. However, the impact of the BRCA1/2 mRNA-expression is not well characterized in OC. We investigated BRCA1/2 mRNA-expression in 12 non-neoplastic fallopian tubes and 201 epithelial OCs in relation to their clinical characteristics. We found higher BRCA1/2 mRNA-expression in OCs compared to controls (P = 0.011, P < 0.001, respectively). BRCA1 mutated OCs exhibited lower BRCA1 (P = 0.014) but higher BRCA2 mRNA-expression (P = 0.001). Low BRCA1-expression was associated with favorable overall survival (OS) (P = 0.012) and low BRCA2-expression with better progression-free survival (PFS) and OS (P = 0.004, P = 0.001, respectively). A subgroup-analysis showed that this effect was confined only to the BRCA1-wildtype cancers. Cox-regression confirmed the prognostic significance of BRCA1-expression for OS (P = 0.028). Independency of the prognostic value of BRCA2-expression for PFS (P = 0.045) and OS (P = 0.015) was restricted to high-grade serous OCs. Fully platinum-sensitivity was characterized by lower BRCA1/2 mRNA-expression in BRCA1-wildtype cancers in comparison to platinum-refractory OC. Our findings may reflect higher platinum-sensitivity due to reduced capacity of DNA damage repair in tissues with low BRCA1/2-expression. In this context, especially in BRCA-wildtype cancers both parameters could also be potential predictors for PARP-sensitivity.

Background On March 16, 2020, the federal government of Austria declared a nationwide lockdown due to the COVID-19 pandemic. Since the lockdown, screening examinations and routine checkups have been restricted to prevent the spread of the virus and to increase the hospitals’ bed capacity across the country. This resulted in a severe decline of patient referrals to the hospitals. Objective To assess the impact of the COVID-19 pandemic on the rate of newly diagnosed gynecological and breast cancers in Austria. Methods Data of 2077 patients from 18 centers in Austria with newly diagnosed gynecological or breast cancer between January and May 2019 and January and May 2020 were collected. Clinical parameters, including symptoms, performance status, co-morbidities, and referral status, were compared between the time before and after the COVID-19 outbreak. Results Our results showed a slight increase of newly diagnosed cancers in January and February 2020 as compared with 2019 (+2 and +35%, respectively) and a strong decline in newly diagnosed tumors since the lockdown: −24% in March 2020 versus March 2019, −49% in April 2020 versus April 2019, −49% in May 2020 versus May 2019. Two-thirds of patients diagnosed during the pandemic presented with tumor-specific symptoms compared with less than 50% before the pandemic (p<0.001). Moreover, almost 50% of patients in 2020 had no co-morbidities compared with 35% in 2019 (p<0.001). Patients, who already had a malignant disease, were rarely diagnosed with a new cancer in 2020 as compared with 2019 (11% vs 6%; p<0.001). Conclusions The lockdown led to a decreased number of newly diagnosed gynecological and breast cancers. The decreased accessibility of the medical services and postponed diagnosis of potentially curable cancers during the COVID-19 pandemic may be a step backwards in our healthcare system and might impair cancer treatment outcomes. Therefore, new strategies to manage early cancer detection are needed to optimize cancer care in a time of pandemic in the future.

Cancer immunotherapy has emerged as one of the most promising approaches in oncology, and comprises the activation of the immune system to induce tumor immune surveillance or to reverse the tumor immune escape. Different therapeutic strategies for ovarian carcinoma have evolved over the years. Already 30 years ago, the first clinical studies focused on modulating the tumor cytokine network with special attention to interferon-mediated immune responses. With the exploration of specific tumor antigens such as NY-ESO-1, which is expressed in ovarian carcinoma and other malignancies, the development of therapeutic cancer vaccines has been pursued initiating the era of personalized anti-cancer medicine. Almost at the same time, the adoptive transfer of genetically modified autologous tumor-reactive T-cells occurred, but response rates in ovarian carcinoma were disappointing. Today, probably the most promising therapeutic approach in this context is the blockade of immune checkpoints, such as programed cell death protein 1 (PD-1) and one of its ligands (PD-L1) or cytotoxic T-cell lymphocyte-associated antigen 4 (CTLA-4), which has demonstrated impressive response rates in malignant melanoma and non-small cell lung cancer. Despite increasing availability of treatment approaches that target tumor immune surveillance in ovarian carcinoma, selecting patient groups that particularly benefit from these treatment modalities is clinically challenging as predictive biomarkers are lacking. Here, we summarize different immunotherapy approaches in ovarian cancer and discuss why immunotherapy in ovarian cancer is still in its infancy.