Ovarian cancer. Clinical practice guidelines in oncology

Disparities in ovarian cancer survival at the only NCI-designated cancer center in Kansas

BACKGROUND

This study examined the impact of geographic distance on survival outcomes for patients receiving treatment for ovarian cancer at the only NCI-designated cancer center (NCI-CC) in Kansas.

METHODS

We identified ovarian cancer patients treated at the University of Kansas Cancer Center between 2010 and 2015. Demographic factors and clinical characteristics were abstracted. The main outcome measure was overall survival according to geographic distance from the institution. Kaplan Meier survival curves and Cox proportional hazard models were generated using SAS v9.4.

RESULTS

220 patients were identified. Survival analysis based on distance from the institution demonstrated that patients who lived ≤10 miles from the institution had worse overall survival (p = 0.0207) and were more likely to have suboptimal cytoreductive surgery (p = 0.0276). Lower estimated median income was also associated with a 1.54 increased risk of death, 95% CI (1.031-2.292), p = 0.0347.

CONCLUSIONS

We determined that ovarian cancer survival disparities exist in our patient population. Lower rates of optimal cytoreductive surgery has been identified as a possible driver of poor prognosis for patients who lived in proximity to our institution.

Adipocyte microenvironment promotes Bclxl expression and confers chemoresistance in ovarian cancer cells

Resistance to mitochondria-initiated apoptosis is a hallmark of chemoresistant cancer stem cells including CD44+/MyD88+ epithelial ovarian cancer (EOC) stem cells. This is controlled by members of the Bcl₂ family of proteins, which function as rheostats of mitochondrial stability. We observed a differential expression profile of Bcl₂ family members comparing the chemoresistant EOC stem cells and the chemosensitive CD44-/MyD88- EOC cells. Chemoresistant EOC stem cells surprisingly express higher levels of the pro-apoptotic members Bak and Bax compared to the chemosensitive EOC cells. In addition, whereas chemosensitive EOC cells preferentially express Bcl₂, chemoresistant EOC stem cells preferentially express Bcl_xl. In the EOC stem cells, 40% knock-down of Bcl_xl expression was sufficient to induce the full activation of caspases and this can be reversed by concurrent knock-down of Puma. More importantly, we demonstrate that Bcl_xl expression levels in EOC cells is dynamic and can be regulated by microenvironments that are enriched with the pro-inflammatory cytokine IL-6 such as the cancer stem cell and adipocyte niches. Adipocyte-induced upregulation of Bcl_xl correlated with acquisition of chemoresistance and thus demonstrates how a specific microenvironment can regulate the expression of apoptotic proteins and confer chemoresistance.

Intraperitoneal chemotherapy for ovarian cancer using sustained-release implantable devices

INTRODUCTION

Epithelial ovarian cancer (EOC) remains to be the most lethal of all gynecological malignancies mainly due to its asymptomatic nature. The late stages are manifested with predominant metastases confined to the peritoneal cavity. Although there has been a substantial progress in the treatment avenue with different therapeutic interventions, the overall survival rate of patients remain poor due to relapse and drug resistance.

AREAS COVERED

The pharmacokinetic advantages offered by intraperitoneal (IP) chemotherapy due to peritoneal-plasma barrier can be potentially exploited for EOC relapse treatment. The ability to retain high concentrations of chemo-drugs with high AUC peritoneum/plasma for prolonged durations in the peritoneal cavity can be utilized effectively through the clinical adoption of drug delivery systems (DDSs) which obviates the need for indwelling catheters. The metronomic dosing strategy could enhance anti-tumor efficacy with a continuous, low dose of chemo-drugs providing minimal systemic toxicity.

EXPERT OPINION

The development of a feasible, non-catheter based, IP DDS, retaining the peritoneal-drug levels, with less systemic levels could offer significant survival advantages as a patient-compliant therapeutic strategy. Suturable-implantable devices based on metronomic dosing, eluting drug in a sustained manner at low doses, could be implanted surgically post-debulking for treatment of refractory EOC patients.

Novel approach for the detection of intraperitoneal micrometastasis using an ovarian cancer mouse model

Patients with epithelial ovarian cancer have the best overall survival when maximal surgical effort is accomplished. However, despite numerous technological advances, surgery still relies primarily on white-light reflectance and the surgeon’s vision. As such, micrometastases are usually missed and most patients clinically classified as a complete responder eventually recur and succumb to the disease. Our objective is to develop optical enhancers which can aid in the visualization of ovarian cancer micrometastasis. To this end we developed a nanoparticle (NP) platform, which is specifically targeted to the tumor microenvironment. Targeting is achieved by coating FDA-approved PLGA-PEG NP with the peptide sequence RGD, which binds with high affinity to αVβ3 integrins present in both the tumor-associated neovasculature and on the surface of ovarian cancer cells. Administration of the NP platform carrying fluorescent dyes to mice bearing intraperitoneal ovarian cancer allowed visualization of tumor-associated vasculature and its contrast against normal blood vessels. More importantly, we demonstrate the visualization of intraperitoneal ovarian cancer micrometastasis as small as 100 μm with optimal resolution. Finally, we demonstrate that the fluorescent dye cargo was able to penetrate intra-tumorally. Such modality could be used to allow microscopic surgical debulking to assure maximal surgical effort.

Surgical treatment pattern and outcomes in epithelial ovarian cancer patients from a cancer institute in Kerala, India

Objective

To evaluate the treatment and survival pattern of patients with advanced epithelial ovarian cancer.

Methods and results

Retrospective study of all advanced epithelial ovarian cancer patients treated in the department of gynaecologic oncology from an academic centre, in a four year period from 1 January 2008–31 December 2011.

Selection criteria

All patients with advanced epithelial ovarian cancer (stage III and IV) who underwent surgery from 2008–2011and had a follow-up of at least three months after completion of treatment were included. The decision on whether primary surgery or neoadjuvant chemotherapy (NACT) in advanced ovarian cancer was based on age, performance status, clinical and imaging findings.

Results

A total of 178 cases of epithelial ovarian cancer were operated on during this four year period. Among them 28 patients were recurrent cases, 22 had early stages of ovarian cancer, and the rest 128 had stage III and IV ovarian cancer. In these 128 patients, 50(39.1%) underwent primary surgery and 78(60.9%) had NACT followed by surgery. In the primary surgery group 36(72.0%) patients had optimal debulking while in the NACT group 59(75.6%) patient had optimal debulking. With a median follow-up of 34 months, the median overall survival (OS) and progression free survival (PFS) was 53 and 49 months respectively. Patients who underwent primary surgery had better median PFS than patients who had NACT (56 months versus 39 months, p = 0.002). In stage III C the difference median PFS was significant for those treated with primary surgery when compared with NACT (55 months versus 39 months, p = 0.012). In patients who had optimal debulking to no residual disease (n = 90), primary surgery gave a significant improved PFS (59 months versus 38 months, p = 0.001) when compared with NACT. In univariate analysis, NACT was associated with increased risk of death (HR: 0.350; CI: 0.177–0.693).

Conclusion

In advanced epithelial ovarian cancer, primary surgery seems to have a definite survival advantage over NACT in patients who can be optimally debulked to no residual disease.

Risk factors and indications for 30-day readmission after primary surgery for epithelial ovarian cancer

BACKGROUND

To identify patients at risk for postoperative morbidities, we evaluated indications and factors associated with 30-day readmission after epithelial ovarian cancer surgery.

METHODS

Patients undergoing primary surgery for epithelial ovarian cancer between January 2, 2003, and December 29, 2008, were evaluated. Univariable and multivariable logistic regression models were fit to identify factors associated with 30-day readmission. A parsimonious multivariable model was identified using backward and stepwise variable selection.

RESULTS

In total, 324 (60.2%) patients were stage III and 91 (16.9%) were stage IV. Of all 538 eligible patients, 104 (19.3%) were readmitted within 30 days. Cytoreduction to no residual disease was achieved in 300 (55.8%) patients, and 167 (31.0%) had measurable disease (≤1 cm residual disease). The most common indications for readmission were surgical site infection (SSI; 21.2%), pleural effusion/ascites management (14.4%), and thromboembolic events (12.5%). Multivariate analysis identified American Society of Anesthesiologists score of 3 or higher (odds ratio, 1.85; 95% confidence interval, 1.18-2.89; P = 0.007), ascites [1.76 (1.11-2.81); P = 0.02], and postoperative complications during initial admission [grade 3-5 vs none, 2.47 (1.19-5.16); grade 1 vs none, 2.19 (0.98-4.85); grade 2 vs none, 1.28 (0.74-2.21); P = 0.048] to be independently associated with 30-day readmission (c-index = 0.625). Chronic obstructive pulmonary disease was the sole predictor of readmission for SSI (odds ratio, 3.92; 95% confidence interval, 1.07-4.33; P = 0.04).

CONCLUSIONS

Clinically significant risk factors for 30-day readmission include American Society of Anesthesiologists score of 3 or higher, ascites and postoperative complications at initial admission. The SSI and pleural effusions/ascites are common indications for readmission. Systems can be developed to predict patients needing outpatient management, improve care, and reduce costs.

Epithelial ovarian cancer in older women: defining the best management approach

Epithelial ovarian cancer is a cancer of older women. In fact, almost half of women diagnosed with ovarian cancer will be older than age 64, and 25% will be older than age 74. Therefore, it is crucial to examine the available data in older populations to optimize the therapeutic approach without negatively affecting the quality of life permanently. Unfortunately, little prospective data are available in this under-represented population of women. Although ovarian cancer traditionally has been approached with aggressive cytoreductive surgery, older patients may benefit from a less aggressive surgical approach and, in some cases, may be candidates for neoadjuvant chemotherapy followed by an interval cytoreduction. Modalities do exist for assessing an older woman's ability to tolerate surgery and chemotherapy, and these tools should be familiar to clinicians who are caring for this population of women in making treatment decisions. Ongoing planned trials to evaluate pretreatment assessment for older patients will provide objective, feasible, clinical tools for applying our treatment-based knowledge. Future trials of both surgery and chemotherapy, including a focus on the sequence of these two treatment modalities, are crucial to guide decision making in this vulnerable population and to improve outcomes for all.

Tumor-associated macrophages contribute to tumor progression in ovarian cancer

Ovarian cancer is the leading cause of death in women with gynecological malignancy and improvements in current treatments are needed. As with many other solid cancers, the ovarian tumor microenvironment is emerging as a key player in tumor progression and a potential therapeutic target. The tumor microenvironment contains several non-malignant cell types that are known to contribute to tumor progression and metastasis. Included in this population of non-malignant cells are several different types of immune cells, of which tumor-associated macrophages (TAMs) are the most abundant. An increasing amount of evidence is emerging to suggest that TAMs display a unique activation profile in ovarian tumors and are able to create an immunosuppressive microenvironment, allowing tumors to evade immune detection and promoting tumor progression. Therefore, an increased understanding of how these immune cells interact with tumor cells and the microenvironment will greatly benefit the development of more effective immunotherapies to treat ovarian cancer. This review focuses on the role of TAMs in the ovarian tumor microenvironment and how they promote tumor progression.

Methylation and histone deacetylase inhibition in combination with platinum treatment in patients with advanced malignancies

PURPOSE

The combination of DNA methylation inhibitors and histone deacetylase inhibitors is synergistic in gene expression activation and may overcome platinum resistance. Sequential treatment with azacitidine and valproic acid (VPA) in combination with carboplatin may overcome resistance to platinum-based therapy, and we conducted a phase I trial to assess safety, maximum tolerated dose (MTD), and clinical correlates. Experimental Design Patients with advanced solid tumors refractory to standard therapy were eligible. In cohorts of escalating doses, patients received azacitidine for 5 days from days 1 to 5, VPA for 7 days from days 5 to 11, and carboplatin starting in the second cycle on days 3 and 10. Clinical correlates included evaluation of epigenetic changes, methylation patterns, and histone acetylation levels in peripheral blood mononuclear cells.

RESULTS

Thirty-two patients were treated. The MTD was 75 mg/m(2) azacitidine, 20 mg/kg VPA, and AUC 3.0 carboplatin. Minor responses or stable disease lasting ≥ 4 months were achieved by six patients (18.8 %), including three with platinum-resistant or platinum-refractory ovarian cancer. The most common adverse events grade ≥ 3 were fatigue (81 %) and neutropenia (69 %). Dose-limiting toxicity occurred in six patients (18.8 %), including four patients with grade 3 altered mental status. Death receptor 4 (DR4) methylation was shown to decrease in a subset of patients, but there was no relationship with tumor response or number of cycles received.

CONCLUSIONS

Combination of azacitidine, VPA, and carboplatin demonstrates decreased DR4 methylation and modest evidence of antitumor activity in patients with heavily treated advanced malignancies.

The use of CT findings to predict extent of tumor at primary surgery for ovarian cancer

BACKGROUND

High tumor dissemination (HTD) is a major risk factor for serious morbidity after primary ovarian cancer (OC) surgery, particularly in medically compromised patients. We performed a pilot study of whether CT findings could predict extent of disease and surgical complexity necessary in advanced OC.

METHODS

Preoperative CT images for patients with advanced OC from 1997-2003 were evaluated for rigorously defined disease-related findings and compared to both the findings at exploration and the required surgical procedures. Associations were assessed by the chi-square test.

RESULTS

Forty-six cases met inclusion criteria. Mean age was 66.4y, and 76% had residual disease (RD) 1cm or less. CT and surgical findings correlated (sensitivity/specificity) as follows: diaphragm disease (48%/100%); surface liver (100%/93%); omental cake (72%/65%); any sigmoid involvement (54%/100%); ascites (44%/100%); extra-pelvic large bowel involvement (29%/91%). When diaphragm disease and omental cake were present, HTD was found in all cases (positive predictive value and specificity=100%, sensitivity 48%). For CT findings of liver, large bowel and spleen involvement there was a strong trend toward resection (P=0.001, P=0.06 and P=0.06, respectively).

CONCLUSIONS

The findings of diaphragm disease and omental cake on CT scan are highly predictive for high tumor dissemination (HTD) and thus likelihood of extensive surgery required to achieve low residual disease. In addition, multiple CT findings correlate strongly with the need for higher surgical complexity which should facilitate preoperative planning and/or triage to specialized centers. These preliminary data suggest specific CT findings can be used to optimize treatment planning.

Distinct subpopulations of epithelial ovarian cancer cells can differentially induce macrophages and T regulatory cells toward a pro-tumor phenotype

PROBLEM

Presence of immune infiltrates in the tumor does not always correlate with an anti-tumoral immune response. We previously identified two subpopulations of epithelial ovarian cancer (EOC) cells with differential cytokine profile. We hypothesize that these two subpopulations of EOC cells may differentially regulate the immune phenotype in the tumor microenvironment and therefore affect the immune response.

METHOD OF STUDY

Macrophages derived from CD14+ monocytes and naive CD4+T cells were treated with conditioned media from two subpopulations of EOC cells. Differentiation markers and phagocytic activity were measured by western blot analysis and flow cytometry. Cytokine levels were quantified using xMAP technology.

RESULTS

Type I EOC cells are able to enhance macrophages' capacity for tumor repair and renewal by enhancing expression of scavenger receptors and by promoting the secretion of cytokines associated with tissue repair. On the other hand, type II EOC cells are able to create a tolerant microenvironment and prevent an immune response by inducing macrophages' to secrete IL-10 and by promoting the generation of T regs.

CONCLUSION

We demonstrate that each ovarian cancer cell subpopulation can induce a unique phenotype of macrophages and T cells, both associated with tumor-supportive function.

Human ovarian cancer stem/progenitor cells are stimulated by doxorubicin but inhibited by Mullerian inhibiting substance

Women with late-stage ovarian cancer usually develop chemotherapeutic-resistant recurrence. It has been theorized that a rare cancer stem cell, which is responsible for the growth and maintenance of the tumor, is also resistant to conventional chemotherapeutics. We have isolated from multiple ovarian cancer cell lines an ovarian cancer stem cell-enriched population marked by CD44, CD24, and Epcam (3+) and by negative selection for Ecadherin (Ecad-) that comprises less than 1% of cancer cells and has increased colony formation and shorter tumor-free intervals in vivo after limiting dilution. Surprisingly, these cells are not only resistant to chemotherapeutics such as doxorubicin, but also are stimulated by it, as evidenced by the significantly increased number of colonies in treated 3+Ecad- cells. Similarly, proliferation of the 3+Ecad- cells in monolayer increased with treatment, by either doxorubicin or cisplatin, compared with the unseparated or cancer stem cell-depleted 3-Ecad+ cells. However, these cells are sensitive to Mullerian inhibiting substance (MIS), which decreased colony formation. MIS inhibits ovarian cancer cells by inducing G1 arrest of the 3+Ecad- subpopulation through the induction of cyclin-dependent kinase inhibitors. 3+Ecad- cells selectively expressed LIN28, which colocalized by immunofluorescence with the 3+ cancer stem cell markers in the human ovarian carcinoma cell line, OVCAR-5, and is also highly expressed in transgenic murine models of ovarian cancer and in other human ovarian cancer cell lines. These results suggest that chemotherapeutics may be stimulative to cancer stem cells and that selective inhibition of these cells by treating with MIS or targeting LIN28 should be considered in the development of therapeutics.

Open-label feasibility study of pazopanib, carboplatin, and paclitaxel in women with newly diagnosed, untreated, gynaecologic tumours: a phase I/II trial of the AGO study group

Introduction:

Although most patients with advanced gynaecologic malignancies respond to first-line treatment with platinum-taxane doublets, a significant proportion of patients relapse. Combining targeted agents that have non-overlapping mechanisms of action with chemotherapy may potentially increase the disease-free interval. Accordingly, this study evaluated the feasibility of combining pazopanib, an oral angiogenesis inhibitor, with paclitaxel and carboplatin.

Methods:

This open-label, phase I/II study planned to evaluate the safety and efficacy of paclitaxel 175 mg m^–2 plus carboplatin (AUC5 (Arm A) or AUC6 (Arm B)) once in every 3 weeks for up to six cycles with either 800 or 400 mg per day pazopanib.

Results:

Dose-limiting toxicities (DLTs) were observed in two of the first six patients enrolled at pazopanib 800 mg plus paclitaxel 175 mg m^–2 plus carboplatin AUC5. Of the six patients enrolled in the next and lowest dosing level planned in the study, pazopanib 400 mg plus paclitaxel 175 mg m^–2 plus carboplatin AUC5, two patients also experienced DLTs and the study was terminated. Two of the 4 DLTs observed overall were gastrointestinal perforations. Severe myelotoxicity was reported in 6 of 12 patients.

Conclusion:

Combining either 800 or 400 mg per day pazopanib with standard carboplatin/paclitaxel chemotherapy is not a feasible treatment option.

Stathmin 1, a marker of PI3K pathway activation and regulator of microtubule dynamics, is expressed in early pelvic serous carcinomas

BACKGROUND

Most high-grade pelvic serous carcinomas (HGPSCs) arise from fallopian tube epithelium (FTE). To date, few markers have been shown to characterize FTE transformation. Stathmin 1 (STMN1) is a candidate oncogene whose activity is influenced by p53, p27Kip1 (p27), and PI3K/Akt pathway activation. As a microtubule destabilizing protein, STMN1 regulates cytoskeletal dynamics, cell cycle progression, mitosis, and cell migration. This study examines the expression of STMN1 and its negative regulator p27 along the morphologic continuum from normal FTE to invasive carcinoma.

METHODS

STMN1 and p27 expression were examined by immunohistochemistry (IHC) in benign (n=12) and malignant (n=13) fallopian tubes containing normal epithelium, morphologically benign putative precursor lesions ("p53 signatures"), potential transitional precursor lesions ("proliferative p53 signatures"), tubal intraepithelial carcinoma (TIC), and/or invasive serous carcinoma. STMN1 expression was further assessed in 131 late-stage HGPSCs diagnosed as primary ovarian and in 6 ovarian cancer cell lines by IHC and Western blot, respectively.

RESULTS

STMN1 expression was absent in benign FTE and infrequently detected in p53 signatures. However, it was weakly expressed in proliferative p53 signatures and robustly induced upon progression to TIC and invasive carcinoma, typically accompanied by decreased p27 levels. STMN1 was expressed in >80% of high-grade serous ovarian carcinomas and cell lines.

CONCLUSIONS

STMN1 is a novel marker of early serous carcinoma that may play a role in FTE tumor initiation. Our data are consistent with a model by which STMN1 overexpression, resulting from loss of p27-mediated regulation, may potentiate aberrant cell proliferation, migration, and/or loss of polarity during early tumorigenesis.

Phase 1b-2a study to reverse platinum resistance through use of a hypomethylating agent, azacitidine, in patients with platinum-resistant or platinum-refractory epithelial ovarian cancer

BACKGROUND

Sequential treatment with azacitidine can induce re-expression of epigenetically silenced genes through genomic DNA hypomethylation and reverse carboplatin resistance of epithelial ovarian cancer cells. A phase 1b-2a clinical trial of this sequential combination of azacitidine and carboplatin was initiated in patients with platinum-resistant or platinum-refractory epithelial ovarian cancer.

METHODS

Patients with pathologically confirmed intermediate-grade or high-grade epithelial ovarian cancer who developed disease progression within 6 months (resistant disease, n = 18 patients) or during a platinum-based therapy (refractory disease, n = 12 patients) were eligible. All patients had measurable disease.

RESULTS

Thirty patients received a total of 163 cycles of treatment. This regimen produced 1 complete response, 3 partial responses (overall response rate [ORR], 13.8%), and 10 cases of stable disease among 29 evaluable patients. For those patients who achieved clinical benefits, the median duration of the treatment was 7.5 months. The median progression-free survival (PFS) and overall survival (OS) for all patients were 3.7 months and 14 months, respectively. Patients with platinum-resistant disease achieved an ORR of 22%, with a median PFS of 5.6 months and a median OS of 23 months. The predominant toxicities were fatigue and myelosuppression. Correlative studies indicated that DR4 methylation in peripheral blood leukocytes was decreased during treatment in 3 of 4 objective responders (75%), but in only 5 of 13 nonresponders (38%).

CONCLUSIONS

To the authors' knowledge, the results of the current study provide the first clinical evidence that a hypomethylating agent may partially reverse platinum resistance in patients with ovarian cancer. Further clinical evaluation of hypomethylating agents in combination with carboplatin is warranted.