Role of Cancer Side Population Stem Cells in Ovarian Cancer Angiogenesis

Ovarian cancer is one of the most common gynecologic malignancies. Recurrence and metastasis often occur after treatment, and it has the highest mortality rate of all gynecological tumors. Cancer stem cells (CSCs) are a small population of cells with the ability of self-renewal, multidirectional differentiation, and infinite proliferation. They have been shown to play an important role in tumor growth, metastasis, drug resistance, and angiogenesis. Ovarian cancer side population (SP) cells, a type of CSC, have been shown to play roles in tumor formation, colony formation, xenograft tumor formation, ascites formation, and tumor metastasis. The rapid progression of tumor angiogenesis is necessary for tumor growth; however, many of the mechanisms driving this process are unclear as is the contribution of CSCs. The aim of this review was to document the current state of knowledge of the molecular mechanism of ovarian cancer stem cells (OCSCs) in regulating tumor angiogenesis.

Efficacy and safety of anti-angiogenic drug monotherapy and combination therapy for ovarian cancer: a meta-analysis and trial sequential analysis of randomized controlled trials

Background

As the development of novel anti-angiogenic drugs and the continuous evolution of guideline recommendations, the efficacy and safety of anti-angiogenic agents in ovarian cancer (OC) remains unclear. Consequently, a meta-analysis was carried out to assess the efficacy and safety of anti-angiogenic drug monotherapy and combination therapy for OC.

Methods

An exhaustive literature review was performed across multiple databases, including PubMed, Embase, Web of Science, and Cochrane, encompassing all relevant randomized controlled trials (RCTs) up until 6 April 2024. The evaluation of efficacy outcomes incorporated progression-free survival (PFS), overall survival (OS), and objective response rate (ORR). Safety was assessed through the occurrence of any grade adverse events (AEs) and grade ≥3 AEs. Synthesis of the data involved the calculation of hazard ratios (HRs), relative risks (RRs), and their corresponding 95% confidence intervals (CIs) and prediction intervals (PIs). Trial sequential analysis was executed employing TSA v0.9.5.10 Beta software, STATA 12.0, and R software 4.3.1.

Results

In this meta-analysis, 35 RCTs were included, encompassing 16,199 subjects in total. The overall analysis indicated that anti-angiogenic drug combination therapy significantly improved PFS (HR [95% CI] = 0.678 [0.606-0.759], 95% PI: 0.415-1.108), OS (HR [95% CI] = 0.917 [0.870-0.966], 95% PI: 0.851-0.984), and ORR (RR [95% CI] = 1.441 [1.287-1.614], 95% PI: 1.032-2.014), but also increased the incidence of grade ≥3 AEs (RR [95% CI] = 1.137 [1.099-1.177], 95% PI: 1.011-1.252). The analysis did not corroborate any benefit of anti-angiogenic monotherapy over placebo concerning PFS (HR [95% CI] = 0.956 [0.709-1.288], 95% PI: 0.345-2.645) and OS (HR [95% CI] = 1.039 [0.921-1.173], 95% PI: 0.824-1.331). However, it was observed that monotherapy with anti-angiogenic drugs did increase the incidence of any grade AEs (RR [95% CI] = 1.072 [1.036-1.109], 95% PI: 0.709-1.592).

Conclusion

Our study confirmed the PFS, OS, and ORR benefits of anti-angiogenic drug combination therapy for OC patients. The efficacy results of anti-angiogenic monotherapy necessitates further evaluation as more RCTs become available. Clinicians should be vigilant of AEs when administering anti-angiogenic agents in a clinical setting.

Deciphering the Molecular Mechanisms behind Drug Resistance in Ovarian Cancer to Unlock Efficient Treatment Options

Ovarian cancer is a highly lethal form of gynecological cancer. This disease often goes undetected until advanced stages, resulting in high morbidity and mortality rates. Unfortunately, many patients experience relapse and succumb to the disease due to the emergence of drug resistance that significantly limits the effectiveness of currently available oncological treatments. Here, we discuss the molecular mechanisms responsible for resistance to carboplatin, paclitaxel, polyadenosine diphosphate ribose polymerase inhibitors, and bevacizumab in ovarian cancer. We present a detailed analysis of the most extensively investigated resistance mechanisms, including drug inactivation, drug target alterations, enhanced drug efflux pumps, increased DNA damage repair capacity, and reduced drug absorption/accumulation. The in-depth understanding of the molecular mechanisms associated with drug resistance is crucial to unveil new biomarkers capable of predicting and monitoring the kinetics during disease progression and discovering new therapeutic targets.

Clinical Observations and Outcomes in Advanced Low-Grade Serous Carcinoma of the Ovary: Case Series from a Tertiary Cancer Center

Low-grade serous carcinoma (LGSC) is a rare histologic subtype of ovarian cancer. We present detailed management of 15 cases of advanced LGSC from a tertiary cancer center of India. Fifteen cases of advanced LGSC who underwent cytoreductive surgery (CRS) were analyzed from a prospectively maintained database. Baseline demographic characteristics, surgical details, and chemotherapy details were recorded. Descriptive statistics were summarized, and progression-free survival (PFS) and overall survival (OS) were estimated. The median age was 37 years. Nine patients had received NACT. All cases were FIGO stage III. Mean PCI was 15. Eleven patients had a completeness of cytoreduction score of 0-1. The median surgical time was 7.5 h; nine patients required multiple gastrointestinal resections. Median blood loss was 2500 ml. Median postoperative ventilation, ICU stay, and hospital stays were 1, 2, and 16 days, respectively. One patient had a grade III complication. Four patients received adjuvant chemotherapy. There was no postoperative mortality at the end of 90 days of surgery. All the patients except one were offered hormonal maintenance therapy. At a median follow-up of 43 months, 4 patients were disease-free, 9 had a recurrence, one died of disease progression, and one was lost to follow-up. Most recurrences were locoregional in the peritoneal cavity or pelvis. Four-year OS and PFS were 71.8% and 29.7%, respectively. Advanced LGSCs occur mostly in young premenopausal women with favorable oncologic outcomes. Optimal CRS is the mainstay of treatment. Relative chemo-resistance and hormone receptor positivity provide an excellent therapeutic opportunity for endocrine therapy.

Heterogeneity and treatment landscape of ovarian carcinoma

Ovarian carcinoma is characterized by heterogeneity at the molecular, cellular and anatomical levels, both spatially and temporally. This heterogeneity affects response to surgery and/or systemic therapy, and also facilitates inherent and acquired drug resistance. As a consequence, this tumour type is often aggressive and frequently lethal. Ovarian carcinoma is not a single disease entity and comprises various subtypes, each with distinct complex molecular landscapes that change during progression and therapy. The interactions of cancer and stromal cells within the tumour microenvironment further affects disease evolution and response to therapy. In past decades, researchers have characterized the cellular, molecular, microenvironmental and immunological heterogeneity of ovarian carcinoma. Traditional treatment approaches have considered ovarian carcinoma as a single entity. This landscape is slowly changing with the increasing appreciation of heterogeneity and the recognition that delivering ineffective therapies can delay the development of effective personalized approaches as well as potentially change the molecular and cellular characteristics of the tumour, which might lead to additional resistance to subsequent therapy. In this Review we discuss the heterogeneity of ovarian carcinoma, outline the current treatment landscape for this malignancy and highlight potentially effective therapeutic strategies in development.

Metronomic chemotherapy in ovarian cancer

Translational research and the development of targeted therapies have transformed the therapeutic landscape in epithelial ovarian cancer over the last decade. However, recurrent ovarian cancer continues to pose formidable challenges to therapeutic interventions, necessitating innovative strategies to optimize treatment outcomes. Current research focuses on the development of pharmaceuticals that target potential resistance pathways to DNA repair pathways. However, the cost and toxicity of some of these therapies are prohibitive and majority of patients lack access to clinical trials. Metronomic chemotherapy, characterized by the continuous administration of low doses of chemotherapeutic agents without long treatment breaks, has emerged as a promising approach with potential implications beyond recurrent setting. It acts primarily by inhibition of angiogenesis and activation of host immune system. We here review the mechanism of action of metronomic chemotherapy, as well as its current role, limitations, and avenues for further research in the management of epithelial ovarian cancer.

A tumor-infiltrating immune cells-related pseudogenes signature based on machine-learning predicts outcomes and immunotherapy responses in ovarian cancer

Previous researches have provided evidence for the significant involvement of pseudogenes in immune-related functions across different types of cancer. However, the mechanisms by which pseudogenes regulate immunity in ovarian cancer (OV) and their potential impact on clinical outcomes remain unclear. To address this gap in knowledge, our study utilized a novel computational framework to analyze a total of 491 samples from three public datasets. We employed a combination of 10 machine-learning algorithms to construct a signature known as the tumor-infiltrating immune cells-related pseudogenes signature (TIICPS). The TIICPS, consisting of 12 pseudogenes, demonstrated independent prognostic value for overall survival, surpassing conventional clinical traits, 62 published signatures, and TP53 and BRCA mutation status in three cohorts. Patients with low TIICPS exhibited heightened immune-related pathways, intricate genomic alterations, substantial immune infiltration, and greater potential for immunotherapy efficacy. Consequently, TIICPS holds promise as a predictive tool for prognosis and immunotherapy response in ovarian cancer.

Genetic characteristics of platinum-sensitive ovarian clear cell carcinoma

OBJECTIVE

Most ovarian clear cell carcinomas are resistant to platinum-based chemotherapy, while a small subset shows a positive response. The aim of this study was to clarify the clinical, pathological and genetic characteristics of platinum-sensitive ovarian clear cell carcinomas.

METHODS

The study included 53 patients with stage III-IV ovarian clear cell carcinoma who had residual tumours after primary surgery and received platinum-based therapy between 2009 and 2018. A retrospective examination of platinum sensitivity was performed using the criterion of ≥6 months from the last day of first-line platinum therapy until recurrence/progression. Cases determined to be platinum-sensitive were subjected to immunohistochemical staining, genomic analyses using target sequencing (i.e. NCC Oncopanel) and homologous recombination deficiency (myChoice® HRD Plus) assays.

RESULTS

Of the 53 stage III-IV ovarian clear cell carcinoma cases, 11 (21%) were platinum-sensitive. These cases showed better progression-free and overall survival than platinum-resistant cases (hazard ratio = 0.16, P < 0.001). Among the seven sensitive cases whose tumour tissues were available for molecular profiling, five were pure ovarian clear cell carcinoma based on pathological and genetic features, whereas the remaining two cases were re-diagnosed as high-grade serous ovarian carcinoma. The pure ovarian clear cell carcinomas lacked BRCA1 and BRCA2 mutations, consistent with the absence of the homologous recombination deficiency phenotype, whereas two cases (40%) had ATM mutations. By contrast, the two high-grade serous ovarian carcinoma cases had BRCA1 or BRCA2 mutations associated with the homologous recombination deficiency phenotype.

CONCLUSION

The subset of platinum-sensitive ovarian clear cell carcinomas includes a majority with pure ovarian clear cell carcinoma features that lack the homologous recombination deficiency phenotype.

Exploiting a living biobank to delineate mechanisms underlying disease-specific chromosome instability

Chromosome instability (CIN) is a cancer hallmark that drives tumour heterogeneity, phenotypic adaptation, drug resistance and poor prognosis. High-grade serous ovarian cancer (HGSOC), one of the most chromosomally unstable tumour types, has a 5-year survival rate of only ~30% - largely due to late diagnosis and rapid development of drug resistance, e.g., via CIN-driven ABCB1 translocations. However, CIN is also a cell cycle vulnerability that can be exploited to specifically target tumour cells, illustrated by the success of PARP inhibitors to target homologous recombination deficiency (HRD). However, a lack of appropriate models with ongoing CIN has been a barrier to fully exploiting disease-specific CIN mechanisms. This barrier is now being overcome with the development of patient-derived cell cultures and organoids. In this review, we describe our progress building a Living Biobank of over 120 patient-derived ovarian cancer models (OCMs), predominantly from HGSOC. OCMs are highly purified tumour fractions with extensive proliferative potential that can be analysed at early passage. OCMs have diverse karyotypes, display intra- and inter-patient heterogeneity and mitotic abnormality rates far higher than established cell lines. OCMs encompass a broad-spectrum of HGSOC hallmarks, including a range of p53 alterations and BRCA1/2 mutations, and display drug resistance mechanisms seen in the clinic, e.g., ABCB1 translocations and BRCA2 reversion. OCMs are amenable to functional analysis, drug-sensitivity profiling, and multi-omics, including single-cell next-generation sequencing, and thus represent a platform for delineating HGSOC-specific CIN mechanisms. In turn, our vision is that this understanding will inform the design of new therapeutic strategies.

Cytoreductive Surgery (CRS) and HIPEC for Advanced Ovarian Cancer with Peritoneal Metastases: Italian PSM Oncoteam Evidence and Study Purposes

Ovarian cancer is the eighth most common neoplasm in women with a high mortality rate mainly due to a marked propensity for peritoneal spread directly at diagnosis, as well as tumor recurrence after radical surgical treatment. Treatments for peritoneal metastases have to be designed from a patient's perspective and focus on meaningful measures of benefit. Hyperthermic intraperitoneal chemotherapy (HIPEC), a strategy combining maximal cytoreductive surgery with regional chemotherapy, has been proposed to treat advanced ovarian cancer. Preliminary results to date have shown promising results, with improved survival outcomes and tumor regression. As knowledge about the disease process increases, practice guidelines will continue to evolve. In this review, we have reported a broad overview of advanced ovarian cancer management, and an update of the current evidence. The future perspectives of the Italian Society of Surgical Oncology (SICO) are discussed conclusively.

Management of oligometastatic ovarian cancer recurrence during PARP inhibitor maintenance

OBJECTIVE

The benefit of surgery and maintenance treatment with PARP inhibitors (PARPi) has been clearly demonstrated in ovarian cancer. Also, the efficacy and safety of stereotactic body radiotherapy has been shown in patients with metastatic, persistent, and recurrent disease. The aim of this study is to evaluate the management of oligometastatic progression during PARPi maintenance treatment.

METHODS

This is an observational, retrospective, single-arm study conducted from June 2017 to December 2020 in patients with recurrent ovarian cancer with oligometastatic progression under PARPi maintenance treatment and receiving surgery or stereotactic body radiotherapy for such recurrence. PARPi treatment was continued until further progression of the disease. The primary objective of the study was the median prolongation of the treatment-free interval-p (without platinum) after local treatment.

RESULTS

A total of 186 patients with ovarian cancer were treated with PARPi at recurrence. Of these, 30 (16%) developed oligometastatic progression. The median age was 49.5 years (range 35-73). Olaparib, niraparib and rucaparib were administered to 33%, 60%, and 7% of patients, respectively. The median prolongation of the treatment-free interval-p of patients treated with surgery or stereotactic body radiotherapy was 6 and 10 months, respectively (p=0.53). The median treatment-free interval-p of patients treated with surgery or stereotactic body radiotherapy at the time of oligometastatic progression was 32 and 29 months, respectively (p=0.44). At the time of this publication, 50% of patients are still on treatment with PARPi following progression.

CONCLUSIONS

Patients with recurrent ovarian cancer who have oligometastic progression during PARPi maintenance may continue to benefit from PARPi if combined with local treatment.

Application of Arsenic Trioxide-Based Combined Sequential Chemotherapy in Recurrent Resistant and Refractory Ovarian Cancers: A Single-Center, Open Phase II Clinical Study

Objective

Arsenic trioxide (ATO) has been effectively used for the treatment of hematological malignancies and some solid tumors, while ATO effects were not tested clinically in epithelial ovarian cancer (EOC).

Methods

Patients with primary or secondary platinum-resistant EOC were enrolled from October 2015 to December 2019. Patients were mainly treated with ATO-based combined sequential chemotherapy as follows: Regimen 1 (ATO combined taxanes weekly therapy); Regimen 2 (ATO + taxanes + 5-fluorouracil + adriamycin ± bevacizumab sequential chemotherapy), for 5 patients platinum-free interval >12 months, added oxaliplatin). Prespecified end points in this cohort included confirmed best overall response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and safety.

Results

A total of 33 patients were enrolled in this study. After a median follow-up time of 22.1 months (range 5.5–42.9 months), ORR was 42% and DCR was 85%. The overall PFS was 9.5 months (range 1–38.4 months). The main side effect was myelosuppression.

Conclusions

ATO-based sequential combined chemotherapy is effective for primary and recurrent drug-resistant EOC patients in clinical phase II trials. The associated side effects could be controlled, while further study is needed.

The efficacy and safety of angiogenesis inhibitors for recurrent ovarian cancer: a meta‑analysis

OBJECTIVE

To investigate the efficacy and safety of angiogenesis inhibitors in the treatment of recurrent ovarian cancer (OC).

METHODS

Electronic databases including PubMed, Web of Science, and the Cochrane Library were searched to find eligible studies until August 10, 2021. The data on overall survival (OS), progression-free survival (PFS), and objective response rate (ORR) were pooled. Furthermore, grade ≥ 3 adverse events (AEs) were investigated.

RESULTS

A total of 13 studies with 3953 patients were included. Compared with control group, angiogenesis inhibitors resulted in significant improvement in PFS (hazard ratio (HR) = 0.61, 95%CI, 0.54-0.69), OS (HR = 0.88, 95%CI, 0.81-0.95), and ORR (odds ratio (OR) = 2.15, 95% CI, 1.74-2.65). However, angiogenesis inhibitors were associated with a higher risk of grade ≥ 3 AEs (relative risk (RR), 1.20, 95% CI, 1.04-1.38).

CONCLUSION

Angiogenesis inhibitors can improve ORR, PFS, and OS in patients with recurrent OC, but they can increase the incidence of AEs ≥ 3.

A Benzenesulfonamide-Based Mitochondrial Uncoupler Induces Endoplasmic Reticulum Stress and Immunogenic Cell Death in Epithelial Ovarian Cancer

Epithelial ovarian cancer (EOC) is the leading cause of death from gynecologic malignancies and requires new therapeutic strategies to improve clinical outcomes. EOC metastasizes in the abdominal cavity through dissemination in the peritoneal fluid and ascites, efficiently adapt to the nutrient-deprived microenvironment, and resist current chemotherapeutic agents. Accumulating evidence suggests that mitochondrial oxidative phosphorylation is critical for the adaptation of EOC cells to this otherwise hostile microenvironment. Although chemical mitochondrial uncouplers can impair mitochondrial functions and thereby target multiple, essential pathways for cancer cell proliferation, traditional mitochondria uncouplers often cause toxicity that precludes their clinical application. In this study, we demonstrated that a mitochondrial uncoupler, specifically 2,5-dichloro-N-(4-nitronaphthalen-1-yl)benzenesulfonamide, hereinafter named Y3, was an antineoplastic agent in ovarian cancer models. Y3 treatment activated AMP-activated protein kinase and resulted in the activation of endoplasmic reticulum stress sensors as well as growth inhibition and apoptosis in ovarian cancer cells in vitro Y3 was well tolerated in vivo and effectively suppressed tumor progression in three mouse models of EOC, and Y3 also induced immunogenic cell death of cancer cells that involved the release of damage-associated molecular patterns and the activation of antitumor adaptive immune responses. These findings suggest that mitochondrial uncouplers hold promise in developing new anticancer therapies that delay tumor progression and protect patients with ovarian cancer against relapse.

Mesothelial-to-Mesenchymal Transition and Exosomes in Peritoneal Metastasis of Ovarian Cancer

Most patients with ovarian cancer (OvCA) present peritoneal disseminated disease at the time of diagnosis. During peritoneal metastasis, cancer cells detach from the primary tumor and disseminate through the intraperitoneal fluid. The peritoneal mesothelial cell (PMC) monolayer that lines the abdominal cavity is the first barrier encountered by OvCA cells. Subsequent progression of tumors through the peritoneum leads to the accumulation into the peritoneal stroma of a sizeable population of carcinoma-associated fibroblasts (CAFs), which is mainly originated from a mesothelial-to-mesenchymal transition (MMT) process. A common characteristic of OvCA patients is the intraperitoneal accumulation of ascitic fluid, which is composed of cytokines, chemokines, growth factors, miRNAs, and proteins contained in exosomes, as well as tumor and mesothelial suspended cells, among other components that vary in proportion between patients. Exosomes are small extracellular vesicles that have been shown to mediate peritoneal metastasis by educating a pre-metastatic niche, promoting the accumulation of CAFs via MMT, and inducing tumor growth and chemoresistance. This review summarizes and discusses the pivotal role of exosomes and MMT as mediators of OvCA peritoneal colonization and as emerging diagnostic and therapeutic targets.

Emerging molecular alterations leading to histology-specific targeted therapies in ovarian cancer beyond PARP inhibitors

After more than 30 years of a one-size-fits-all approach in the management of advanced ovarian cancer, in 2018 the SOLO1 trial results have introduced a new era of personalized medicine. A deeper knowledge of ovarian cancer biology and the development of new drugs targeting specific molecular pathways have led to biomarker-driven phase 3 trials with practice changing results. Thereafter, platinum-based combinations are no longer the only therapeutic options available in first line setting and poly-ADP ribose polymerase inhibitors maintenance therapy has become the mainstay in patients with tumor harboring a homologous recombination defect. However, most of the recent therapeutic breakthroughs regard high grade serous carcinoma, the most frequent ovarian cancer subtype, and only few improvements have occurred in the management of less common histotypes. Moving towards the next challenges, we aimed to investigate and review new potential molecular targets in ovarian cancer, according to histotype, starting from promising molecular drivers and matched drugs that have been investigated in early and late-stage clinical trials or conceptualized in preclinical studies.

Chemotherapy resistance in epithelial ovarian cancer: Mechanisms and emerging treatments

Ovarian cancer (OC) remains a fatal malignancy because most patients experience recurrent disease, which is resistant to chemotherapy. The outcomes for patients with platinum-resistant OC are poor, response rates to further chemotherapy are low and median survival is lower than 12 months. The complexity of platinum-resistant OC, which comprises a heterogeneous spectrum of diseases, is indeed far from being completely understood. Therefore, comprehending tumors' biological behaviour to identify reliable biomarkers, which may predict responses to therapies, is a demanding challenge to improve OC management. In the age of precision medicine, efforts to overcome platinum resistance in OC represent a dynamic and vast field in which innovative drugs and clinical trials rapidly develop. This review will present the exceptional biochemical environment implicated in OC and highlights mechanisms of chemoresistance. Furthermore, innovative molecules and new therapeutic opportunities are presented, along with currently available therapies and ongoing clinical trials.

A multidisciplinary approach remains the best strategy to improve and strengthen the management of ovarian cancer (Review)

Ovarian cancer represents one of the most aggressive female tumors worldwide. Over the decades, the therapeutic options for the treatment of ovarian cancer have been improved significantly through the advancement of surgical techniques as well as the availability of novel effective drugs able to extend the life expectancy of patients. However, due to its clinical, biological and molecular complexity, ovarian cancer is still considered one of the most difficult tumors to manage. In this context, several studies have highlighted how a multidisciplinary approach to this pathology improves the prognosis and survival of patients with ovarian cancer. On these bases, the aim of the present review is to present recent advantages in the diagnosis, staging and treatment of ovarian cancer highlighting the benefits of a patient‑centered care approach and on the importance of a multidisciplinary team for the management of ovarian cancer.

Efficacy of an optimal ovarian cancer screening: a best-case scenario study based on real-world data

PURPOSE

To date, ovarian cancer screening in asymptomatic women has not shown a mortality benefit. The aim of this simulation study was to outline the impact of different histological subtypes on a potential stage-shift, achieved by screening.

METHODS

Real-world data were derived in the period of 2000-2017 from the Klinischen Tumorregister Austria. We estimated five-year overall survival (OS) of patients with ovarian cancer regarding different histological subtypes and FIGO stages. A theoretical model was generated predicting the trend of OS mediated by an eventual down-shifting of ovarian cancer from FIGO stage III/IV to FIGO stage I/II by screening, considering the influence of different histological subtypes.

RESULTS

3458 ovarian cancer patients were subdivided according to histological subtypes and FIGO classification. Major difference in distribution of histological types was found between FIGO stage I/II and III/IV. A theoretical down-shift of tumors from high to low FIGO stages based on our registry calculations showed that the five-year OS would increase from 50% to nearly 80% by perfect screening.

CONCLUSION

In our simulation study, we showed that down-shifting ovarian cancers by successful screening might increase OS by 30 percentage point. Our results underscore the importance to recognize ovarian cancer as a heterogenous disease with distinct epidemiologic, molecular and clinical features. The individual characteristic of each histotype is of utmost impact on the definition of screening aims and may influence early detection and stage-shift. Efficacy of screening is mainly dependent on detection of high-risk cancer types and not the slow growing low-grade types.

Artificial Intelligence Based on Blood Biomarkers Including CTCs Predicts Outcomes in Epithelial Ovarian Cancer: A Prospective Study

Objective

We aimed to develop an ovarian cancer-specific predictive framework for clinical use platinum-sensitivity and prognosis using machine learning methods based on multiple biomarkers, including circulating tumor cells (CTCs).

Patients and Methods

We enrolled 156 epithelial ovarian cancer (EOC) patients, randomly assigned into the training and validation cohorts. Eight machine learning classifiers, including Random Forest (RF), Support Vector Machine, Gradient Boosting Machine, Conditional RF, Neural Network, Naive Bayes, Elastic Net, and Logistic Regression, were used to derive predictive information from 11 peripheral blood parameters, including CTCs. Through the advanced CanPatrol CTC-enrichment technique, we detect CTCs and classify them into subpopulations: epithelial, mesenchymal, and hybrids. Survival curves were generated by Kaplan–Meier method and calculated through the Log rank test.

Results

Machine learning techniques, especially the Random Forest classifier, were superior to conventional regression-based analyses in predicting multiple clinical parameters related to EOC. The values for the receiver operating characteristic (ROC) curve for segregating EOC with advanced clinical stages and platinum-sensitivity were 0.796 (95% CI, 0.727–0.866) and 0.809 (95% CI, 0.742–0.876), respectively. Stepwise, we used the unsupervised clustering analysis to identify EOC subgroups with significantly worse overall survival (OS), especially in the advanced-stage group with the p-value of 0.0018 (HR, 2.716; 95% CI, 1.602–4.605) for progression-free survival (PFS) and 0.0037 (HR, 2.359; 95% CI, 1.752–6.390) for overall survival (OS).

Conclusion

Machine learning systems could provide risk stratification for EOC patients before initial intervention through blood variables, including circulating tumor cells. The predictive algorithms could facilitate personalized treatment options through promising pre-treatment stratification of EOC patients.

Trial registration

ChiCTR-DDD-16009601 Registered 25 October 2016.

The impact of Pegylated liposomal doxorubicin in recurrent ovarian cancer: an updated meta-analysis of randomized clinical trials

Background

Previous meta-analysis studies suggested that pegylated liposomal doxorubicin (PLD) may improve the survival rate of patients with recurrent ovarian cancer. The aim of the present meta-analysis, then, was to further update the role of PLD in the treatment of recurrent ovarian cancer.

Methods

We performed a literature search using the electronic databases Medicine, EMBASE, Web of Science, and the Cochrane Library to 27 July 2020. We only restricted the randomized clinical trials. Study-specific hazard ratios and 95% confidence interval (HR/95% CI) and risk ratios and 95% confidence interval (RR/95% CI) were pooled using a random-effects model.

Results

Ten studies (12 trials) were included after screening 940 articles. We categorized the eligible studies into two groups: the doublet regimens (four trials, 1767 patients) showed that PLD plus carbo provided superior progression-free survival (PFS) (HR, 0.85; 95% CI, 0.74–0.97) and similar overall survival (OS) (HR, 1.00; 95% CI, 0.88–1.14) compared to paclitaxel (PAC) plus carboplatin (carbo). PLD plus carbo was associated with significantly more anemia and thrombocytopenia, and other side effects were well tolerated. The monotherapy regimens (eight trials, 1980 patients) showed that PLD possessed a similar PFS (HR, 1.02; 95% CI, 0.90–1.16) and OS (HR, 0.88; 95% CI, 0.77–1.01) relative to other monotherapies. PLD alone was also more associated with mucositis/stomatitis and hand-foot syndrome, while other side effects were well tolerated.

Conclusions

In platinum-sensitive recurrent ovarian cancer, PLD plus carbo was more effective than PAC plus carbo, while in platinum-resistant or -refractory recurrent ovarian cancer, PLD exhibited similar survival to other monotherapies. Regarding side effects, PLD plus carbo and mono chemotherapy were both well tolerated.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13048-021-00790-4.

The systemic treatment of recurrent ovarian cancer revisited

Treatment approaches for relapsed ovarian cancer have evolved over the past decade from a calendar-based decision tree to a patient-oriented biologically driven algorithm. Nowadays, platinum-based chemotherapy should be offered to all patients with a reasonable chance of responding to this therapy. The treatment-free interval for platinum is only one of many factors affecting patients' eligibility for platinum re-treatment. Bevacizumab increases the response to chemotherapy irrespective of the cytotoxic regimen and can be valuable in patients with an urgent need for symptom relief (e.g. pleural effusion, ascites). For patients with recurrent high-grade ovarian cancer, which responds to platinum-based treatment, maintenance therapy with a poly(ADP-ribose) polymerase inhibitor can be offered, regardless of the BRCA mutation status. Here we review contemporary decision-making processes in the systemic treatment of relapsed ovarian cancer.

Treatment of Recurrent Epithelial Ovarian Cancer

Epithelial ovarian cancer is the most common cause of death from gynecological tumors. Most patients with advanced ovarian cancer develop recurrence after concluding first-line therapy, making further lines of therapy necessary. The choice of therapy depends on various criteria such as tumor biology, the patient's general condition (ECOG), toxicity, previous chemotherapy, and response to chemotherapy. The platinum-free or treatment-free interval determines the potential response to repeat platinum-based therapy. If patients have late recurrence, i.e. > 6 months after the end of the last platinum-based therapy (i.e., they were previously platinum-sensitive), then they are usually considered suitable for another round of a platinum-based combination therapy. Patients who are not considered suitable for platinum-based chemotherapy are treated with a platinum-free regimen such as weekly paclitaxel, pegylated liposomal doxorubicin (PLD), gemcitabine, or topotecan. Treatment for the patient subgroup which is considered suitable for platinum-based therapy but cannot receive carboplatin due to uncontrollable hypersensitivity reactions may consist of trabectedin and PLD. While the use of surgery to treat recurrence has long been a controversial issue, new findings from the DESKTOP III study of the AGO working group have drawn attention to this issue again, particularly for patients with a platinum-free interval of > 6 months and a positive AGO score. Clinical studies have also shown the efficacy of angiogenesis inhibitors such as bevacizumab and the PARP inhibitors olaparib, niraparib and rucaparib. These drugs have substantially changed current treatment practice and expanded the range of available therapies. It is important to differentiate between purely maintenance therapy after completing CTX, continuous maintenance therapy during CTX, and the therapeutic use of these substances. The PARP inhibitors niraparib, olaparib and rucaparib have already been approved for use by the FDA and the EMA. The presence of a BRCA mutation is a predictive factor for a better response to PARP inhibitors.

Clinical relevance of cancer stem cell chemotherapeutic assay for recurrent ovarian cancer

Introduction

Disease recurrence and progression of ovarian cancer is common with the development of platinum-resistant or refractory disease. This is due in large part to the presence of chemo-resistant cancer stem cells (CSCs) that contribute to tumor propagation, maintenance, and treatment resistance. We developed a CSCs drug cytotoxicity assay (ChemoID) to identify the most effective chemotherapy treatment from a panel of FDA approved chemotherapies.

Methods

Ascites and pleural fluid samples were collected under physician order from 45 consecutive patients affected by 3rd-5th relapsed ovarian cancer. Test results from the assay were used to treat patients with the highest cell kill drugs, taking into consideration their health status and using dose reductions, as needed. A retrospective chart review of CT and PET scans was used to determine patients' outcomes for tumor response, time to recurrence, progression-free survival (PFS), and overall survival (OS).

Results

We observed that recurrent ovarian cancer patients treated with high-cell kill chemotherapy agents guided by the CSCs drug response assay had an improvement in the median PFS corresponding to 5.4 months (3rd relapse), 3.6 months (4th relapse), and 3.9 months (5th relapse) when compared to historical data. Additionally, we observed that ovarian cancer patients identified as non-responders by the CSC drug response assay had 30 times the hazard of death compared to those women that were identified as responders with respective median survivals of 6 months vs. 13 months. We also found that ChemoID treated patients on average had an incremental cost-effectiveness ratio (ICER) between -$18,421 and $7,241 per life-year saved (LYS).

Conclusions

This study demonstrated improved PFS and OS for recurrent ovarian cancer patients treated with assay-guided chemotherapies while decreasing the cost of treatment.

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Ovarian cancer progression and recurrence is mostly attributed to the presence of cancer stem cells (CSCs), which are chemo-resistant.

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Eliminating CSCs is a strategy that could improve patients' outcome.

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We developed a CSC drug cytotoxicity assay to identify the most effective chemotherapy treatment from a panel of FDA approved chemotherapies.

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Recurrent ovarian cancer patients treated with high-cell kill chemotherapy agents guided by the CSCs drug response assay had an improvement in the median PFS when compared to historical data.

Morphological and molecular heterogeneity of epithelial ovarian cancer: Therapeutic implications

Ovarian epithelial cancer (OEC) is the most lethal gynecologic malignancy. Despite current chemotherapeutic and surgical options, this high lethality can be attributed to multiple factors, including late-stage presentation. In order to optimize OEC treatment, it is important to highlight that it is composed of five main subtypes: high-grade serous ovarian carcinoma (HGSOC), low-grade serous ovarian carcinoma (LGSOC), endometrioid ovarian carcinoma (EOC), ovarian clear cell carcinoma (CCOC), and mucinous ovarian carcinoma (MOC). These subtypes differ in their precursor lesions, as well as in epidemiological, morphological, molecular and clinical features. OEC is one of the tumours in which most pathogenic germline mutations have been identified. Accordingly, up to 20% OC show alterations in BRCA1/2 genes, and also, although with a lower frequency, in other low penetrance genes associated with homologous recombination deficiency (HRD), mismatch repair genes (Lynch syndrome) and TP53. The most important prognostic factor is the 2014 FIGO staging, while older age is also associated with worse survival. HGSOC in all stages and CCC and MOC in advanced stages have the worse prognosis among histological types. Molecular markers have emerged as prognostic factors, particularly mutations in BRCA1/2, which are associated with a better outcome. Regarding treatment, whereas a proportion of HGSOC is sensible to platinum-based treatment and PARP inhibitors due to HRD, the rest of the histological types are relatively chemoresistant. New treatments based in specific molecular alterations are being tested in different histological types. In addition, immunotherapy could be an option, especially for EOC carrying mismatch repair deficiency or POLE mutations.

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The five different histological types have different precursor lesions and epidemiological, morphological, genetic, epigenetic and clinical features.

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Histological type is an important prognostic factor.

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Drugs targeting homologous recombination deficiency have been approved for treatment.

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The use of immunotherapy is limited due to lack of predictive biomarkers

Treatment of recurrent epithelial ovarian cancer

The majority of patients with advanced ovarian cancer progress after first-line therapy and require further treatment. Tumor biology, prior chemotherapy, responses to previous therapy, performance status, and toxicity are the characteristics that influence treatment choice. These criteria have been linked to the time between relapse and last platinum therapy: the platinum-free interval. Today, patients are classified as either those who are eligible for a new platinum-based therapy or those for whom platinum is not an option. A nonplatinum regimen should be administered to patients who are not candidates for platinum re-treatment. This group includes patients with early relapse after, or progression during, previous platinum-based chemotherapy and patients with platinum intolerability. A single agent such as weekly paclitaxel, pegylated liposomal doxorubicin (PLD), gemcitabine, or topotecan represents the standard. For patients not treated with bevacizumab in the first line, this drug should be added to chemotherapy. For patients for whom platinum rechallenge is an option (because they are potentially platinum-responsive), different strategies are available with the incorporation of biological drugs targeting angiogenesis or the mechanisms of DNA repair. A BRCA mutation status predicts a better response to platinum and poly(adenosine diphosphate-ribose) polymerase (PARP) inhibition. PARP inhibitors and antiangiogenic drugs have proven efficacy as maintenance therapy after chemotherapy and concurrently with chemotherapy, respectively. These agents have changed current practice, although few biomarkers are available to guide decisions. Patients potentially responsive to platinum who cannot receive the drug again can be treated with a combination of trabectedin and PLD, the most active nonplatinum therapy in this setting.

A nine-gene signature related to tumor microenvironment predicts overall survival with ovarian cancer

Mounting evidence suggests that immune cell infiltration within the tumor microenvironment (TME) is a crucial regulator of carcinogenesis and therapeutic efficacy in ovarian cancer (OC). In this study, 593 OC patients from TCGA were divided into high and low score groups based on their immune/stromal scores resulting from analysis utilizing the ESTIMATE algorithm. Differential expression analysis revealed 294 intersecting genes that influencing both the immune and stromal scores. Further Cox regression analysis identified 34 differentially expressed genes (DEGs) as prognostic-related genes. Finally, the nine-gene signature was derived from the prognostic-related genes using a Least Absolute Shrinkage and Selection Operator (LASSO) and Cox regression. This nine-gene signature could effectively distinguish the high-risk patients in the training (TCGA database) and validation (GSE17260) cohorts (all p < 0.01). A time-dependent receiver operating characteristic (ROC) analysis showed that the nine-gene signature had a reasonable predictive accuracy (AUC = 0.707, AUC =0.696) in both cohorts. In addition, this nine-gene signature is associated with immune infiltration in TME by Gene Set Variation Analysis (GSVA), and can be used to predict the survival of patients with OC.

Ovarian Cancer, Cancer Stem Cells and Current Treatment Strategies: A Potential Role of Magmas in the Current Treatment Methods

Epithelial ovarian cancer (EOC) constitutes 90% of ovarian cancers (OC) and is the eighth most common cause of cancer-related death in women. The cancer histologically and genetically is very complex having a high degree of tumour heterogeneity. The pathogenic variability in OC causes significant impediments in effectively treating patients, resulting in a dismal prognosis. Disease progression is predominantly influenced by the peritoneal tumour microenvironment rather than properties of the tumor and is the major contributor to prognosis. Standard treatment of OC patients consists of debulking surgery, followed by chemotherapy, which in most cases end in recurrent chemoresistant disease. This review discusses the different origins of high-grade serous ovarian cancer (HGSOC), the major sub-type of EOC. Tumour heterogeneity, genetic/epigenetic changes, and cancer stem cells (CSC) in facilitating HGSOC progression and their contribution in the circumvention of therapy treatments are included. Several new treatment strategies are discussed including our preliminary proof of concept study describing the role of mitochondria-associated granulocyte macrophage colony-stimulating factor signaling protein (Magmas) in HGSOC and its unique potential role in chemotherapy-resistant disease.

Upper Abdominal Resections as Part of Tertiary Cytoreduction for Relapsed Ovarian Cancer

BACKGROUND/AIM

The role of upper abdominal resection as part of debulking surgery for advanced-stage or relapsed ovarian cancer has been widely debated. The aim of this study was to investigate the safety and efficacy of upper abdominal resection as part of tertiary cytoreduction.

PATIENTS AND METHODS

Between 2005 and 2019, 11 cases presenting upper abdominal recurrences after surgically treated ovarian cancer were submitted to surgery with radical intent.

RESULTS

Complete debulking surgery was feasible in eight cases, optimal debulking was performed in two cases, while in one case a suboptimal resection was performed. The most commonly performed upper abdominal resections consisted of liver resection in seven cases, splenectomy in four cases, diaphragmatic resection in three cases, pancreatic tail resection in two cases and partial gastrectomy in another two cases. Postoperative complications were encountered in two cases, while postoperative mortality was null.

CONCLUSION

Extended upper abdominal resection can be safely performed in order to increase the chances of optimal debulking surgery at the time of tertiary cytoreduction.

Outcome according to residual disease (surgeon's report vs pre-chemotherapy imaging) in patients with bevacizumab-treated ovarian cancer: Analysis of the ROSiA study

BACKGROUND AND OBJECTIVES

The single-arm ROSiA study evaluated frontline bevacizumab for advanced ovarian cancer. We explored how discordant surgically and radiologically assessed postoperative residual disease affects outcomes.

METHODS

After debulking surgery, 1021 patients received 4 to 8 cycles of carboplatin-paclitaxel plus bevacizumab until progression or up to 24 months. The primary endpoint was safety; progression-free survival (PFS) was a secondary endpoint. We performed post hoc exploratory PFS analyses in four subgroups: surgeon-reported no visible residuum (NVR) without target lesions; surgeon-reported NVR with target lesions; macroscopic (≤1 cm) residuum; and >1 cm residuum.

RESULTS

Surgical and radiological assessments were concordant in 94% of patients; 61 patients (6%; 21% of those with surgeon-reported NVR) had NVR with target lesions. Median PFS was numerically longest in patients with concordant surgically/radiologically assessed NVR (35.5 months), intermediate for surgeon-reported NVR with target lesions (31.8 months), and shortest for visible residuum (27.9 and 20.2 months for visible residuum ≤1 and >1 cm, respectively). One-year and 2-year PFS rates showed the same pattern.

CONCLUSIONS

These analyses suggest that prognosis is potentially worse in patients with radiologically detected target lesions despite surgeon-reported NVR compared with concordant NVR by both assessment methods. Postsurgical imaging may add valuable prognostic information.

Epithelial ovarian cancer: Evolution of management in the era of precision medicine

Ovarian cancer is the second most common cause of gynecologic cancer death in women around the world. The outcomes are complicated, because the disease is often diagnosed late and composed of several subtypes with distinct biological and molecular properties (even within the same histological subtype), and there is inconsistency in availability of and access to treatment. Upfront treatment largely relies on debulking surgery to no residual disease and platinum-based chemotherapy, with the addition of antiangiogenic agents in patients who have suboptimally debulked and stage IV disease. Major improvement in maintenance therapy has been seen by incorporating inhibitors against poly (ADP-ribose) polymerase (PARP) molecules involved in the DNA damage-repair process, which have been approved in a recurrent setting and recently in a first-line setting among women with BRCA1/BRCA2 mutations. In recognizing the challenges facing the treatment of ovarian cancer, current investigations are enlaced with deep molecular and cellular profiling. To improve survival in this aggressive disease, access to appropriate evidence-based care is requisite. In concert, realizing individualized precision medicine will require prioritizing clinical trials of innovative treatments and refining predictive biomarkers that will enable selection of patients who would benefit from chemotherapy, targeted agents, or immunotherapy. Together, a coordinated and structured approach will accelerate significant clinical and academic advancements in ovarian cancer and meaningfully change the paradigm of care.

Performance of preoperative plasma tumor markers HE4 and CA125 in predicting ovarian cancer mortality in women with epithelial ovarian cancer

Clinical utility of new biomarkers often requires the identification of their optimal threshold. This external validation study was conducted to assess the performance of the preoperative plasma tumor markers HE4 and CA125 optimal cut-offs to predict cancer mortality in women with epithelial ovarian cancer (EOC). Participating women had upfront debulking surgery in the University Hospital of Quebec City (Canada) between 1998 and 2013. A total of 136 women participated in the training cohort (cohort 1) and 177 in the validation cohort (cohort 2). Preoperative plasma HE4 and CA125 levels were measured by Elecsys. Optimal thresholds were identified in the cohort 1 using time-dependent receiver operating characteristic (ROC) curves. Multivariate Cox models were used to validate the biomarkers using their optimal cut-offs in the cohort 2. The likelihood ratio (LR) test was done to test whether the biomarkers added prognostic information beyond that provided by standard prognostic factors. The Areas Under the Curves (AUC) for HE4 and CA125 were respectively 64.2 (95% CI: 54.7-73.6) and 63.1 (95%CI: 53.6-72.6). The optimal thresholds were 277 pmol/L for HE4 and 282 U/ml for CA125. Preoperative plasma HE4 (≥277 pmol/L) was significantly associated with EOC mortality (adjusted hazard ratio (aHR): 1.90; 95% CI:1.09-3.29). The prognostic effect of HE4 was strongest in the subgroup of women with serous ovarian cancer (aHR: 2.42; 95% CI: 1.25-4.68). Using a multivariate model including all standard prognostic factors, this association was maintained (aHR: 2.21; 95% CI: 1.15-4.23). In addition, preoperative plasma HE4 added prediction for death over the standard prognostic markers in women with serous tumors (p-value for LR-test: 0.01). Preoperative CA125 was not associated with cancer mortality, both in women with EOC and in those with serous tumors. Preoperative HE4 is a promising prognostic biomarker in EOC, especially in serous tumor.

Histopathologic response to neoadjuvant chemotherapy as a prognostic biomarker in tubo-ovarian high-grade serous carcinoma: updated Chemotherapy Response Score (CRS) results

OBJECTIVE

The Chemotherapy Response Scoring (CRS) system was developed to enable reproducible reporting of histologic tumor response in interval debulking specimens following neoadjuvant chemotherapy in advanced stage tubo-ovarian high-grade serous carcinoma. This prognostic biomarker has been included in ovarian cancer pathology reporting guidelines (International Collaboration on Cancer Reporting, College of American Pathologists) and in the upcoming European Society for Medical Oncology-European Society of Gynaecological Oncology (ESMO-ESGO) guidelines for ovarian cancer management. We present follow-up data on the CRS validation initiatives and suggest research with novel therapeutic agents incorporating this biomarker.

METHODS

The cohort on whom CRS was originally developed was analyzed after an extended follow-up of an additional 36 months. The CRS histopathologic scoring system was applied to omental sections obtained at interval surgery from all 80 patients. Progression-free and overall survival were re-calculated.

RESULTS

After a median follow-up of 4.3 years the CRS score predicted progression-free survival with an HR of 0.39 (95% CI 0.21 to 0.70), p = 0.002 adjusted for age, stage, and debulking status (median 1.08 vs 2.27 years for CRS1/2 vs CRS3). CRS was also predictive of overall survival with an HR of 0.17 (95% CI 0.07 to 0.44), p = 0.0002 adjusted for age, stage, and debulking status (median 2.55 vs 5.47 years for CRS1/2 vs CRS3).

CONCLUSION

CRS3 is a reproducible prognostic biomarker for improved progression-free and overall survival in stage 3C or 4 tubo-ovarian high-grade serous carcinoma after neoadjuvant chemotherapy. The score, obtained at interval debulking surgery, can help facilitate research and biomarker driven first-line treatment of patients with advanced ovarian cancer.

Treatment decision-making in elderly women with ovarian cancer: an age-based comparison

OBJECTIVE

To investigate treatment choices and outcomes in women with ovarian cancer, comparing elderly (≥75 years) and younger patients (<75 years).

METHODS

A single-center retrospective analysis of patients diagnosed with ovarian cancer between 2010 and 2015. The initial treatment plan and course of treatment were extracted from medical files.

RESULTS

Of 128 included patients, 34% were aged ≥75 years. The initial treatment plan consisted of the combination of cytoreductive surgery and platinum-based doublet chemotherapy (ie, standard treatment) in only 10% of the elderly patients with an indication for this treatment. 5% of these patients completed this treatment without adaptations (compared with 85% and 48%, respectively, in younger patients). 38% of the elderly patients with an indication for cytoreductive surgery and chemotherapy received best supportive care only. Patient preference was an important reason to withhold standard treatment. Surgery- and chemotherapy-related complications and hospital admissions did not differ between groups. Median survival was lower in the elderly (p=0.002) and in patients receiving best supportive care (p<0.001).

CONCLUSIONS

Elderly patients were less frequently treated in accordance with the treatment guideline. To select those older patients who may benefit from (adapted) treatment is challenging. Future studies should evaluate determinants associated with treatment completion to improve outcomes in this vulnerable population.

Harmonising clinical trials within the Gynecologic Cancer InterGroup: consensus and unmet needs from the Fifth Ovarian Cancer Consensus Conference

The Gynecologic Cancer InterGroup (GCIG) Fifth Ovarian Cancer Consensus Conference (OCCC) was held in Tokyo, Japan from 7 to 9 November 2015. It provided international consensus on 15 important questions in 4 topic areas, which were generated in accordance with the mission statement to establish 'International Consensus for Designing Better Clinical Trials'. The methodology for obtaining consensus was previously established and followed during the Fifth OCCC. All 29 clinical trial groups of GCIG participated in program development and deliberations. Draft consensus statements were discussed in topic groups as well as in a plenary forum. The final statements were then presented to all 29 member groups for voting and documentation of the level of consensus. Full consensus was obtained for 11 of the 15 statements with 28/29 groups agreeing to 3 statements, and 27/29 groups agreeing to 1 statement. The high acceptance rate of the statements among trial groups reflects the fact that we share common questions, and recognise important unmet needs that will guide future research in ovarian cancer.

Treatment of recurrent ovarian cancer

Despite optimal surgery and appropriate first-line chemotherapy, ∼70%-80% of patients with epithelial ovarian cancer will develop disease relapse. The same modalities as used primarily are available for treatment of recurrent ovarian cancer (ROC). The rationale for repetitive surgery in ROC was based on a stable body of retrospective data; however, prospective data were missing. Now, preliminary data from the prospective AGO-DESKTOP III give evidence that surgery for ROC seems to be of benefit for selected patients with platinum-sensitive relapse undergoing complete resection. With respect to systemic therapy, tumor histology, BRCA status, the platinum-free interval (PFI) and previous treatment with bevacizumab (anti-VEGF monoclonal antibody) are considered the most important features that influence treatment choice in ROC. In patients with resistant or refractory relapse (PFI < 6 months), monotherapy with a non-platinum drug or participation in clinical trials is indicated. The association of non-platinum monotherapy with bevacizumab, followed by maintenance has been approved in this setting in some European countries due to PFS benefit. In patients with partially sensitive relapse (PFI between 6 and 12 months), two options are available: platinum doublets or non-platinum therapy (single agent or combination). The pegylated liposomal doxorubicin/trabectedin combination represents a viable alternative in patients that cannot receive platinum. In platinum-sensitive patients, treatment with platinum-based combinations is associated with PFS advantage compared with single agents or non-platinum combinations. The presence of germline or somatic BRCA mutations allows platinum-responsive patients to optimize chemotherapy efficacy and prolonging PFS by the use of olaparib (PARP inhibitor) given as maintenance therapy until progression. In patients not pretreated with bevacizumab in first line, the carboplatin/gemcitabine/bevacizumab combination, followed by maintenance is a viable alternative in platinum-sensitive patients (PFI> 6 months). The integration of surgery, with a 'personalized' approach by the use of antiangiogenic agent and of PARP inhibitors is affecting survival of patients with recurrent disease and will help epithelial ovarian cancer to become a chronic disease.

[Recommendations for biomarker testing in epithelial ovarian cancer. A national consensus statement by the Spanish Society of Pathology and the Spanish Society of Medical Oncology]

Advances in the understanding of the histological and molecular characteristics of ovarian cancer now allow 5subtypes to be identified, leading to a more refined therapeutic approach and improved clinical trials. Each of the subtypes has specific histological features and a particular biomarker expression, as well as mutations in different genes, some of which have prognostic and predictive value. CA125 and HE4 are examples of ovarian cancer biomarkers used in diagnosis and follow-up. Currently, somatic or germinal mutations on BRCA1 and BRCA2 genes are the most important biomarkers in epithelial ovarian cancer, having prognostic and predictive value. In this article, a group of experts from the Spanish Society of Medical Oncology and the Spanish Society of Pathology review the histological and molecular characteristics of the 5subtypes of ovarian cancer and describe the most useful biomarkers and mutations for diagnosis, screening and tailored treatment strategy.

Phase II randomized study of PM01183 versus topotecan in patients with platinum-resistant/refractory advanced ovarian cancer

Background

PM01183 is a new compound that blocks active transcription, produces DNA breaks and apoptosis, and affects the inflammatory microenvironment. PM01183 showed strong antitumor activity in preclinical models of cisplatin-resistant epithelial ovarian cancer.

Patients and methods

Patients with platinum-resistant/refractory ovarian cancer were included in a two-stage, controlled, randomized (in a second stage), multicenter, phase II study. Primary endpoint was overall response rate (ORR) by RECIST and/or GCIG criteria. The exploratory first stage (n = 22) confirmed the activity of PM01183 as a single agent at 7.0 mg flat dose every 3 weeks (q3wk). The second stage (n = 59) was randomized and controlled with topotecan on days 1-5 q3wk or weekly (every 4 weeks, q4wk).

Results

ORR was 23% (95% CI, 13%-37%) for 52 PM01183-treated patients. Median duration of response was 4.6 months (95% CI, 2.5-6.9 months), and 23% (95% CI, 0%-51%) of responses lasted 6 months or more. Ten of the 12 confirmed responses were reported for 33 patients with platinum-resistant disease [ORR = 30% (95% CI, 16%-49%)]; for the 29 patients treated with topotecan in the second stage, no responses were found. Median PFS for all PM01183-treated patients was 4.0 months (95% CI, 2.7-5.6 months), and 5.0 months (95% CI, 2.7-6.9 months) for patients with platinum-resistant disease. Grade 3/4 neutropenia in 85% of patients; febrile neutropenia in 21% and fatigue (grade 3 in 35%) were the principal safety findings for PM01183.

Conclusion

PM01183 is an active drug in platinum-resistant/refractory ovarian cancer and warrants further development. The highest activity was observed in platinum-resistant disease. Its safety profile indicates the dose should be adjusted to body surface area (mg/m2).

Trial code

EudraCT 2011-002172-16.

Platinum-Based Neoadjuvant Chemotherapy versus Primary Surgery in Ovarian Carcinoma International Federation of Gynecology and Obstetrics Stages IIIc and IV: A Systematic Review and Meta-Analysis

BACKGROUND/AIM

This study aimed to compare neoadjuvant chemotherapy (NAC) followed by interval debulking surgery (IDS) with primary debulking surgery (PDS) followed by chemotherapy in patients with advanced ovarian carcinoma International Federation of Gynecology and Obstetrics (FIGO) stages IIIc and IV.

METHODS

PubMed, the Cochrane Library, and manual searches were applied to discriminate potentially eligible studies published before June 30, 2016.

RESULTS

A total of 12 comparative studies were finally included; 1,372 patients underwent NAC followed by IDS, and 2,680 patients underwent PDS followed by chemotherapy. For overall pooled estimates, significant between-trial differences were found in the optimal debulking rate, grade 3-5 postoperative adverse reactions, and median overall survival (OS), but no difference was found in the median progression-free survival (PFS). Moreover, a significantly higher incidence was identified in major infections, vascular events, and wound complications for patients in the PDS group.

CONCLUSIONS

This study suggested that NAC followed by IDS could improve the optimal debulking rate and decrease the postoperative adverse reactions for the current studies, but whether it could improve the OS and PFS compared with PDS followed by chemotherapy in patients with ovarian carcinoma FIGO stages IIIc and IV were still needed to be verified by conducting more randomized controlled trials.

Recommendations for biomarker testing in epithelial ovarian cancer: a National Consensus Statement by the Spanish Society of Pathology and the Spanish Society of Medical Oncology

Because of advances in the understanding of histological and molecular characteristics in ovarian cancer, it is now possible to recognize the existence of five subtypes, which in turn has allowed a more refined therapeutic approach and better design of clinical trials. Each of these five subtypes has specific histological features and a particular biomarker expression, as well as mutations in different genes, some of which have prognostic and predictive value. CA125 and HE4 are examples of ovarian cancer biomarkers used in the diagnosis and follow-up of these malignancies. Currently, somatic or germinal mutations on BRCA1 and BRCA2 genes are the most important biomarkers in epithelial ovarian cancer having prognostic and predictive value. This article will review the histological and molecular characteristics of the five subtypes of ovarian cancer, describing the most important biomarkers and mutations that can guide in diagnosis, screening and tailored treatment strategy.

Tertiary cytoreductive surgery in recurrent epithelial ovarian cancer: A multicentre MITO retrospective study

OBJECTIVES

To evaluate the impact of tertiary cytoreductive surgery (TCS) on survival in recurrent epithelial ovarian cancer (EOC), and to determine predictors of complete cytoreduction.

METHODS

A multi-institutional retrospective study was conducted within the MITO Group on a 5-year observation period.

RESULTS

A total of 103 EOC patients with a ≥6month treatment-free interval (TFI) undergoing TCS were included. Complete cytoreduction was achieved in 71 patients (68.9%), with severe post-operative complications in 9.7%, and no cases of mortality within 60days from surgery. Multivariate analysis identified the complete tertiary cytoreduction as the most potent predictor of survival followed by FIGO stage I-II at initial diagnosis, exclusive retroperitoneal recurrence, and TCS performed ≥3years after primary diagnosis. Patients with complete tertiary cytoreduction had a significantly longer overall survival (median OS: 43months, 95% CI 31-58) compared to those with residual tumor (median OS: 33months, 95% CI 28-46; p<0.001). After multivariate adjustment the presence of a single lesion and good (ECOG 0) performance status were the only significant predictors of complete surgical cytoreduction.

CONCLUSIONS

This is the only large multicentre study published so far on TCS in EOC with ≥6month TFI. The achievement of postoperative no residual disease is confirmed as the primary objective also in a TCS setting, with significant survival benefit and acceptable morbidity. Accurate patient selection is of utmost importance to have the best chance of complete cytoreduction.