The role of neoadjuvant chemotherapy followed by interval debulking surgery in advanced ovarian cancer: a systematic review and meta-analysis of randomized controlled trials and observational studies

Frontline Management of Advanced Epithelial Ovarian Cancer: A Comprehensive Statement by the Africa Middle East Cancer Inter-group [AMCI]

Abstract:

Worldwide, ovarian cancer (OC) is one of the leading causes of cancer-related death among women. Despite the recent progress in the treatment of advanced OC, oncologists in many parts of the world still face several difficulties and constraints in their daily management of their patients. In addition to the shortage of resources and expertise, non-adherence to the up to date international guidelines has been identified as a major obstacle towards the improvement of treatment outcomes in the majority of developing countries, including the Middle East and North African (MENA) countries. A multidisciplinary gynecological oncology panel from the MENA region met virtually in December 2020 to discuss the challenges and hurdles faced by the community oncologists in the management of advanced OC. This manuscript reviews the key molecular and clinical studies that shaped the current international guidelines and suggests several modifications to make them more adaptable to the health status of developing countries of this region

Does MIS Play a Role in the Treatment of Advanced Ovarian Cancer?

Neoadjuvant chemotherapy allows a minimally invasive approach for interval debulking in patients with ovarian cancer considered unresectable to no residual disease by laparotomy at diagnosis. The aim of the study was to evaluate the type of surgical approach at interval debulking (ID) after three courses of carboplatin and taxol in patients with unresectable ovarian cancer at diagnosis compared with the type of surgical approach at primary debulking (PD). A secondary objective was to compare the perioperative outcomes of MIS vs. laparotomy at ID. A retrospective review of the type of surgical approach at ID following three courses of carboplatin and taxol was compared with the surgical approach at PD, and a review of the perioperative outcomes of MIS vs. open at ID was performed during the period from 21 January 2012, through 21 February 2013, for stage IIIC > 2 cm or IV epithelial ovarian cancer (EOC) unresectable at diagnosis and the surgical approach at PD. During the study period, 127 patients with stage IIIC or IV EOC met the inclusion criteria. Minimally invasive surgery (MIS), laparoscopic or robotic, was used in 21.6% of patients at ID and in 23.3% of patients at PD. At ID, MIS patients had a shorter hospital stay as compared to laparotomy (2 vs. 8 days; p < 0.001). At 5 year follow-up, 31.5% of EOC patients were alive (ID MIS: 47.5% vs. ID open: 30%; PD MIS: 41% vs. PD open: 28%), while 24.4% had no evidence of disease (ID MIS: 39% vs. ID open: 19.5%; PD MIS: 32% vs. PD open: 22%). Among living patients, 22% had evidence of disease. Neoadjuvant chemotherapy is a form of chemo-debulking and allows a minimally invasive approach at interval debulking in about one-fifth of the patients, with initial disease deemed unresectable to no residual tumor at initial diagnosis.

30-Year Experience With 22 Cases of Malignant Transformation Arising From Ovarian Mature Cystic Teratoma: A Rare Disease

Objective

To investigate the clinical characteristics and survival outcomes of patients with malignant transformation arising from ovarian mature cystic teratoma (MT-MCT).

Methods

This retrospective study included patients with ovarian MCTs at Peking Union Medical College Hospital (PUMCH) during 1990.01-2020.12. When the pathologic histology was MT-MCT, detailed information was collected.

Results

Overall, 7229 ovarian MCT patients and 22 patients with MT-MCT were enrolled. The rate of malignant transformation of all ovarian MCTs was 0.30%. Most patients with MT-MCT were 51 (21–75) years old, and the tumor mass size was 10 (3–30) cm. The typical clinical symptoms were mainly abdominal pain and distension. The levels of tumor markers were elevated on preoperative examination. Early diagnosis could be made by ultrasonic examination, pelvic enhanced MRI and CT. Most patients underwent debulking surgery and adjuvant chemotherapy. The most common histological type to exhibit malignant transformation was squamous cell carcinoma (59.1%), followed by adenocarcinoma (13.6%), carcinoid (9.1%), and borderline tumor (18.2%). The 5-year RFS and OS rates were 54.5% and 81.8%, respectively. Patients with FIGO stage I had the best RFS (P=0.047) and OS (P=0.018), followed by those with FIGO stage II-IV.

Conclusion

MT-MCTs mainly occur in elderly females, are rare and have a poor prognosis. Advanced FIGO stage is a risk factor for survival. Although there is no standard treatment, cytoreductive debulking surgery and adjuvant chemotherapy could be considered. Perimenopausal and menopausal women with MCT should receive surgical treatment.

What underlies the observed hospital volume-outcome relationship?

Background

Studies of the hospital volume-outcome relationship have highlighted that a greater volume activity improves patient outcomes. While this finding has been known for years, most studies to date have failed to delve into what underlies this relationship.

Objective

This study aimed to shed light on the basis of the hospital volume effect on patient outcomes by comparing treatment modalities for epithelial ovarian carcinoma patients.

Data

An exhaustive dataset of 355 patients in first-line treatment for Epithelial Ovarian Carcinoma (EOC) in 2012 in three regions of France was used. These regions account for 15% of the metropolitan French population.

Methods

In the presence of endogeneity induced by a reverse causality between hospital volume and patient outcomes, we used an instrumental variable approach. Hospital volume of activity was instrumented by the distance from patients’ homes to their hospital, the population density, and the median net income of patient municipalities.

Results

Based on our parameter estimates, we found that the rate of complete tumor resection would increase by 15.5 percentage points with centralized care, and by 8.3 percentage points if treatment decisions were coordinated by high-volume centers compared to decentralized care.

Conclusion

As volume alone is an imperfect correlate of quality, policy-makers need to know what volume is a proxy for in order to devise volume-based policies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-021-07449-2.

Prognostic value of systematic lymphadenectomy in patients with ovarian cancer: A systematic review and meta-analysis

OBJECTIVE

To appraise clinical outcomes of systematic lymphadenectomy in women with ovarian cancer based on stage, control group and type of chemotherapy.

STUDY DESIGN

A literature search was conducted on SCOPUS, PUBMED, COCHRANE, MEDLINE, and WEB OF SCIENCE databases. All comparative studies that assess outcomes of systematic lymphadenectomy in patients with ovarian cancer were eligible. Overall survival was analyzed by pooling log hazard ratio (HR) and standard error of multivariable Cox regression models. MOGGE Meta-analysis Matrix is a novel illustration tool that was used to demonstrate multiple subgroup analyses of included studies.

RESULTS

Twenty-two studies were eligible. Systematic lymphadenectomy was associated with better overall survival, that was close to significance, compared to control group (HR 0.93, 95 %CI 0.86-1.00). Among women treated with adjuvant chemotherapy, overall survival improved in women with stage IIB-IV who underwent systematic lymphadenectomy (HR 0.91, 95 %CI 0.84-0.99) and was most significant among patients with stage III to IV (HR 0.85, 95 %CI 0.73-0.99). Systematic lymphadenectomy did not improve survival in women who received neoadjuvant chemotherapy (HR 0.97, 95 %CI 0.73-1.29). Systematic lymphadenectomy was associated with improved progress-free survival compared to control group (HR 0.88, 95 %CI 0.79-0.99).

CONCLUSION

Although data from clinical trials do not support role of systematic lymphadenectomy in advanced ovarian cancer, overall data conveys stage-specific survival benefit. Further clinical trials may be warranted to assess substage survival outcomes in women with advanced stages.

Insights into ovarian cancer care: report from the ANZGOG Ovarian Cancer Webinar Series 2020

Epithelial ovarian cancer (EOC) is among the top ten causes of cancer deaths worldwide, and is one of the most lethal gynecological malignancies in high income countries, with incidence and death rates expected to rise particularly in Asian countries where ovarian cancer is among the 5 most common cancers. Despite the plethora of randomised clinical trials investigating various systemic treatment options in EOC over the last few decades, both progression-free and overall survival have remained at approximately 16 and 40 months respectively. To date the greatest impact on treatment has been made by the use of poly (ADP-ribose) polymerase (PARP) inhibitors in women with advanced EOC and a BRCA1/2 mutation. Inhibition of PARP, the key enzyme in base excision repair, is based on synthetic lethality whereby alternative DNA repair pathways in tumor cells that are deficient in homologous recombination is blocked, rendering them unviable and leading to cell death. The Australia New Zealand Gynaecological Oncology Group (ANZGOG) is the national gynecological cancer clinical trials organization for Australia and New Zealand. ANZGOG's purpose is to improve outcomes and quality of life for women with gynecological cancer through cooperative clinical trials and undertaking multidisciplinary research into the causes, prevention and treatments of gynecological cancer. This review summarizes current ovarian cancer research and treatment approaches presented by Australian and New Zealand experts in the field at the 2020 ANZGOG webinar series entitled "Ovarian Cancer systems of Care".

Effect of tumor burden and radical surgery on survival difference between upfront, early interval or delayed cytoreductive surgery in ovarian cancer

OBJECTIVE

We sought to evaluate the impact on survival of tumor burden and surgical complexity in relation to the number of cycles of neoadjuvant chemotherapy (NACT) in patients with advanced ovarian cancer (OC) with minimal (CC-1) or no residual disease (CC-0).

METHODS

This retrospective study included patients with International Federation of Gynaecology and Obstetrics IIIC-IV stage OC who underwent debulking surgery at 4 high-volume institutions between January 2008 and December 2015. We assessed the overall survival (OS) of primary debulking surgery (PDS group), early interval debulking surgery after 3-4 cycles of NACT (early IDS group) and delayed debulking surgery after 6 cycles (DDS group) with CC-0 or CC-1 according to peritoneal cancer index (PCI) and Aletti score.

RESULTS

Five hundred forty-nine women were included: 175 (31.9%) had PDS, 224 (40.8%) early IDS and 150 (27.3%) DDS. Regardless of Aletti score, median OS after PDS was significantly higher than after early IDS or DDS, but the survival difference was higher in women with an Aletti score <8. Among patients with PCI ≤10, median OS after PDS was significantly higher than after early IDS or DDS. In women with PCI >10, there were no differences between PDS and early IDS, but DDS was associated with decreased OS.

CONCLUSION

The benefit of complete PDS compared with NACT was maximal in patients with a low complexity score. In patients with low tumor burden, there was a survival benefit of PDS over early IDS or DDS. In women with high tumor load, DDS impaired the oncological outcome.

Neoadjuvant chemotherapy before surgery versus surgery followed by chemotherapy for initial treatment in advanced ovarian epithelial cancer

BACKGROUND

Epithelial ovarian cancer presents at an advanced stage in the majority of women. These women require a combination of surgery and chemotherapy for optimal treatment. Conventional treatment has been to perform surgery first and then give chemotherapy. However, there may be advantages to using chemotherapy before surgery.

OBJECTIVES

To assess whether there is an advantage to treating women with advanced epithelial ovarian cancer with chemotherapy before debulking surgery (neoadjuvant chemotherapy (NACT)) compared with conventional treatment where chemotherapy follows debulking surgery (primary debulking surgery (PDS)).

SEARCH METHODS

We searched the following databases up to 9 October 2020: the Cochrane Central Register of Controlled Trials (CENTRAL), Embase via Ovid, MEDLINE (Silver Platter/Ovid), PDQ and MetaRegister. We also checked the reference lists of relevant papers that were identified to search for further studies. The main investigators of relevant trials were contacted for further information.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of women with advanced epithelial ovarian cancer (Federation of International Gynaecologists and Obstetricians (FIGO) stage III/IV) who were randomly allocated to treatment groups that compared platinum-based chemotherapy before cytoreductive surgery with platinum-based chemotherapy following cytoreductive surgery.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed risk of bias in each included trial. We extracted data of overall (OS) and progression-free survival (PFS), adverse events, surgically-related mortality and morbidity and quality of life outcomes.  We used GRADE methods to determine the certainty of evidence.

MAIN RESULTS

We identified 2227 titles and abstracts through our searches, of which five RCTs of varying quality and size met the inclusion criteria. These studies assessed a total of 1774 women with stage IIIc/IV ovarian cancer randomised to NACT followed by interval debulking surgery (IDS) or PDS followed by chemotherapy. We pooled results of the four studies where data were available and found little or no difference with regard to overall survival (OS) (Hazard Ratio (HR) 0.96, 95% CI 0.86 to 1.08; participants = 1692; studies = 4; high-certainty evidence) or progression-free survival in four trials where we were able to pool data (Hazard Ratio 0.98, 95% CI 0.88 to 1.08; participants = 1692; studies = 4; moderate-certainty evidence). Adverse events, surgical morbidity and quality of life (QoL) outcomes were variably and incompletely reported across studies. There are probably clinically meaningful differences in favour of NACT compared to PDS with regard to overall postoperative serious adverse effects (SAE grade 3+): 6% in NACT group, versus 29% in PDS group, (risk ratio (RR) 0.22, 95% CI 0.13 to 0.38; participants = 435; studies = 2; heterogeneity index (I2) = 0%; moderate-certainty evidence). NACT probably results in a large reduction in the need for stoma formation: 5.9% in NACT group, versus 20.4% in PDS group, (RR 0.29, 95% CI 0.12 to 0.74; participants = 632; studies = 2; I2 = 70%; moderate-certainty evidence), and probably reduces the risk of needing bowel resection at the time of surgery: 13.0% in NACT group versus 26.6% in PDS group (RR 0.49, 95% CI 0.30 to 0.79; participants = 1565; studies = 4; I2 = 79%; moderate-certainty evidence). NACT reduces postoperative mortality: 0.6% in NACT group, versus 3.6% in PDS group, (RR 0.16, 95% CI 0.06 to 0.46; participants = 1623; studies = 5; I2 = 0%; high-certainty evidence). QoL on the European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) scale produced inconsistent and imprecise results in three studies (MD -0.29, 95% CI -2.77 to 2.20; participants = 524; studies = 3; I2 = 81%; very low-certainty evidence) but the evidence is very uncertain and should be interpreted with caution.

AUTHORS' CONCLUSIONS

The available high to moderate-certainty evidence suggests there is little or no difference in primary survival outcomes between PDS and NACT. NACT probably reduces the risk of serious adverse events, especially those around the time of surgery, and reduces the risk of postoperative mortality and the need for stoma formation. These data will inform women and clinicians (involving specialist gynaecological multidisciplinary teams) and allow treatment to be tailored to the person, taking into account surgical resectability, age, histology, stage and performance status. Data from an unpublished study and ongoing studies are awaited.

Timing of surgery in patients with partial response or stable disease after neoadjuvant chemotherapy for advanced ovarian cancer

OBJECTIVE

The ideal number of neoadjuvant chemotherapy (NACT) cycles prior to interval tumor-reductive surgery (iTRS) for advanced ovarian cancer is poorly defined. We sought to assess survival stratified by number of NACT cycles and residual disease following iTRS in patients with advanced ovarian cancer with partial response (PR) or stable disease (SD) following 3-4 cycles of NACT.

METHODS

We retrospectively identified patients with advanced high-grade ovarian cancer (diagnosed 2/1/2013 to 2/1/2018) who received at least 3 cycles of NACT and iTRS and had a PR or SD. The population was divided into four groups based on the number of NACT cycles prior to iTRS and residual disease status after (CGR [complete gross residual] or incomplete resection [any amount of residual disease]): 1) 3-4 NACT cycles/CGR, 2) 3-4 NACT cycles/incomplete resection, 3) > 4 cycles/CGR, and 4) >4 cycles/incomplete resection. Overall survival (OS) and progression-free survival (PFS) were estimated using a Kaplan-Meier product-limit estimator and modeled using univariable and multivariable Cox proportional hazards analysis.

RESULTS

The cohort consisted of 265 patients with advanced high-grade ovarian cancer with a median age at diagnosis of 65 years. Most were White (87%), had serous histology (89%), and stage IV disease (57%), with an overall CGR rate of 81%. In a multivariable analysis receipt of >4 NACT cycles was not associated with worse PFS or OS (adjusted hazard ratio [aHR] 1.02, 95% CI 0.74-1.42; aHR 1.12, 95% CI, 0.73-1.72 respectively) than was receipt of 3-4 cycles. Any amount of residual disease was associated with worse PFS and OS regardless of the number of NACT cycles (aHR 1.56, 95% CI 1.09-2.22; aHR 2.38, 95% CI 1.52-3.72 respectively).

CONCLUSIONS

Residual disease was associated with worse survival outcomes regardless of the number of NACT cycles in patients with PR or SD after NACT for advanced high-grade ovarian cancer. These data suggest that the ability to achieve CGR should take precedence in decision-making regarding the timing of surgery.

The hallmarks of ovarian cancer stem cells and niches: Exploring their harmonious interplay in therapy resistance

The concept of a "cancer stem cell" has evolved over the past decades, and research on cancer stem cell biology has entered into a stage of remarkable progress. Cancer stem cells are a major determining factor contributing to the establishment of phenotypic and functional intratumoral heterogeneity in synchronization with their surrounding "cancer stem cell niches." They serve as the driving force for cancer initiation, metastasis, and therapeutic resistance in various types of malignancies. In verity, reciprocal interplay between ovarian cancer stem cells and their niches involves a complex but ingeniously orchestrated tumor microenvironment within the intraperitoneal milieu and especially contribute to chemotherapy resistance in patients with advanced ovarian cancer. Herein, we review the principles of our current understanding of the biological features of ovarian cancer stem cells, focusing mainly on the precise mechanisms underlying acquired chemotherapy resistance. Furthermore, we highlight the specific roles of various cancer-associated stromal and immune cells in creating possible cancer stem cell niches that regulate ovarian cancer stemness.

Chemotherapy versus surgery for initial treatment in advanced ovarian epithelial cancer

BACKGROUND

Epithelial ovarian cancer presents at an advanced stage in the majority of women. These women require surgery and chemotherapy for optimal treatment. Conventional treatment has been to perform surgery first and then give chemotherapy. However, there may be advantages to using chemotherapy before surgery.

OBJECTIVES

To assess whether there is an advantage to treating women with advanced epithelial ovarian cancer with chemotherapy before debulking surgery (neoadjuvant chemotherapy (NACT)) compared with conventional treatment where chemotherapy follows debulking surgery (primary debulking surgery (PDS)).

SEARCH METHODS

We searched the following databases on 11 February 2019: CENTRAL, Embase via Ovid, MEDLINE (Silver Platter/Ovid), PDQ and MetaRegister. We also checked the reference lists of relevant papers that were identified to search for further studies. The main investigators of relevant trials were contacted for further information.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of women with advanced epithelial ovarian cancer (Federation of International Gynaecologists and Obstetricians (FIGO) stage III/IV) who were randomly allocated to treatment groups that compared platinum-based chemotherapy before cytoreductive surgery with platinum-based chemotherapy following cytoreductive surgery.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed risk of bias in each included trial.

MAIN RESULTS

We found 1952 potential titles, with a most recent search date of February 2019, of which five RCTs of varying quality and size met the inclusion criteria. These studies assessed a total of 1713 women with stage IIIc/IV ovarian cancer randomised to NACT followed by interval debulking surgery (IDS) or PDS followed by chemotherapy. We pooled results of the three studies where data were available and found little or no difference with regard to overall survival (OS) (1521 women; Hazard Ratio (HR) 0.95, 95% CI 0.84 to 1.07; I2 = 0%; moderate-certainty evidence) or progression-free survival in four trials where we were able to pool data (1631 women; HR 0.97, 95% CI 0.87 to 1.07; I2 = 0%; moderate-certainty evidence). Adverse events, surgical morbidity and quality of life (QoL) outcomes were poorly and incompletely reported across studies. There may be clinically meaningful differences in favour of NACT compared to PDS with regard to serious adverse effects (SAE grade 3+). These data suggest that NACT may reduce the risk of need for blood transfusion (risk ratio (RR) 0.80; 95% CI 0.64 to 0.99; four studies,1085 women; low-certainty evidence), venous thromboembolism (RR 0.28; 95% CI 0.09 to 0.90; four studies, 1490 women; low-certainty evidence), infection (RR 0.30; 95% CI 0.16 to 0.56; four studies, 1490 women; moderate-certainty evidence), compared to PDS. NACT probably reduces the need for stoma formation (RR 0.43, 95% CI 0.26 to 0.72; two studies, 581 women; moderate-certainty evidence) and bowel resection (RR 0.49, 95% CI 0.26 to 0.92; three studies, 1213 women; moderate-certainty evidence), as well as reducing postoperative mortality (RR 0.18; 95% CI 0.06 to 0.54:five studies, 1571 women; moderate-certainty evidence). QoL on the EORTC QLQ-C30 scale produced inconsistent and imprecise results in two studies (MD -1.34, 95% CI -2.36 to -0.32; participants = 307; very low-certainty evidence) and use of the QLQC-30 and QLQC-Ov28 in another study (MD 7.60, 95% CI 1.89 to 13.31; participants = 217; very low-certainty evidence) meant that little could be inferred.

AUTHORS' CONCLUSIONS

The available moderate-certainty evidence suggests there is little or no difference in primary survival outcomes between PDS and NACT. NACT may reduce the risk of serious adverse events, especially those around the time of surgery, and the need for bowel resection and stoma formation. These data will inform women and clinicians and allow treatment to be tailored to the person, taking into account surgical resectability, age, histology, stage and performance status. Data from an unpublished study and ongoing studies are awaited.

A Prediction Model for Optimal Primary Debulking Surgery Based on Preoperative Computed Tomography Scans and Clinical Factors in Patients With Advanced Ovarian Cancer: A Multicenter Retrospective Cohort Study

OBJECTIVE

This study assessed the predictive value of preoperative computed tomography (CT) scans and clinical factors for optimal debulking surgery (ODS) in patients with advanced ovarian cancer (AOC).

METHODS

Patients with AOC in International Federation of Gynecology and Obstetrics (FIGO) stage III-IV who underwent primary debulking surgery (PDS) between 2016 and 2019 from nine tertiary Chinese hospitals were included. Large-volume ascites, diffuse peritoneal thickening, omental cake, retroperitoneal lymph node enlargement (RLNE) below and above the inferior mesenteric artery (IMA), and suspected pelvic bowel, abdominal bowel, liver surface, liver parenchyma and portal, spleen, diaphragm and pleural lesions were evaluated on CT. Preoperative factors included age, platelet count, and albumin and CA125 levels.

RESULTS

Overall, 296 patients were included, and 250 (84.5%) underwent ODS. The prediction model included age >60 years (P=0.016; prediction index value, PIV=1), a CA125 level >800 U/ml (P=0.033, PIV=1), abdominal bowel metastasis (P=0.034, PIV=1), spleen metastasis (P<0.001, PIV=2), diaphragmatic metastasis (P=0.014, PIV=2), and an RLNE above the IMA (P<0.001, PIV=2). This model had superior discrimination (AUC=0.788>0.750), and the Hosmer-Lemeshow test indicated its stable calibration (P=0.600>0.050). With the aim of maximizing the accuracy of prediction and minimizing the rate of inappropriate explorations, a total PIV ≥5 achieved the highest accuracy of 85.47% and identified patients who underwent suboptimal PDS with a specificity of 100%.

CONCLUSIONS

We developed a prediction model based on two preoperative clinical factors and four radiological criteria to predict unsatisfactory debulking surgery in patients with AOC. The accuracy of this prediction model needs to be validated and adjusted in further multicenter prospective studies.

Comparing Laparotomy with Robot-assisted Interval Debulking Surgery for Patients with Advanced Epithelial Ovarian Cancer Receiving Neoadjuvant Chemotherapy

STUDY OBJECTIVE

Compare survival of patients with advanced epithelial ovarian cancer (EOC) undergoing interval debulking surgery (IDS) with either robot-assisted (R-IDS) or open (O-IDS) approach. Second, we assessed the impact of adjuvant and neoadjuvant chemotherapy (NACT) cycles as independent variables associated with survival in this patient population.

DESIGN

Retrospective cohort study.

SETTING

Single tertiary care center.

PATIENTS

Total of 93 patients diagnosed with advanced EOC who underwent NACT before primary debulking surgery after consultation with a gynecologic oncologist.

INTERVENTIONS

All patients underwent IDS after completion of NACT with either R-IDS or O-IDS between 2011 and 2018 at a single tertiary care center. Exclusion criteria included receiving fewer than 3 or more than 6 cycles of NACT or having concurrent diagnoses of other malignancies during the treatment period.

MEASUREMENTS AND MAIN RESULTS

A total of 93 patients were identified (n = 43 R-IDS; n = 50 O-IDS). Median age (63.0 vs 66.2 years) did not differ between the 2 groups (p = .1). Of the total patients, 91% were optimally cytoreduced (57% R0 and 34% R1), and R0 rate was not influenced by surgical modality (52% O-IDS vs 63% R-IDS, p = .4). Progression-free survival (PFS) and overall survival (OS) did not differ between patients undergoing O-IDS and those undergoing R-IDS (PFS 15.4 vs 16.7 months, p = .7; OS 38.2 vs 35.6 months, p = .7). Cytoreduction to R0 improved both PFS and OS independent of surgical approach. Subgroup analysis showed that, specifically in patients undergoing R-IDS, receiving >6 total cycles of chemotherapy was independently associated with both decreased PFS (hazard ratio 3.85; 95% confidence interval, 1.52-9.73) and OS (hazard ratio 3.97; 95% confidence interval, 1.08-14.59). When analyzed separately, neither NACT nor adjuvant cycle numbers had any effect on survival.

CONCLUSION

In this retrospective study of patients with advanced EOC undergoing IDS after NACT, the use of robot-assisted surgery did not affect debulking success or oncologic survival indices. Receiving >6 total cycles of chemotherapy before IDS was associated with a decrease in both PFS and OS in patients undergoing R-IDS in this cohort and warrants further investigation.

A multivariate analysis of the prognostic impact of tumor burden, surgical timing and complexity after complete cytoreduction for advanced ovarian cancer

OBJECTIVE

To assess the survival benefit of primary debulking surgery (PDS) compared to interval debulking surgery (IDS) after complete cytoreduction (CC-0) or cytoreduction to minimal residual disease (CC-1) in advanced ovarian cancer. Secondary objective was to evaluate the effect of tumor load and surgical complexity on patients' survival.

METHODS

A retrospective multicentric study was designed, including patients with IIIC-IV FIGO stage ovarian cancer who underwent PDS or IDS with CC-0 or CC-1 from January 2008 to December 2015 in four high-volume institutions. Patients were classified in three groups: PDS, IDS after 3-4 cycles of neoadjuvant chemotherapy (NACT), and IDS after 6 cycles. Disease-free survival (DFS) and overall survival (OS) were estimated. Univariable and multivariable analyses were conducted.

RESULTS

We included 549 patients, 175 (31.9%) underwent PDS, 224 (40.8%) had IDS after 3-4 cycles of NACT, and 150 (27.3%) underwent IDS after 6 cycles. Median DFS in PDS, IDS at 3-4 cycles and IDS at 6 cycles were 23.0 months (95%CI = [20.0-29.3]), 18.0 months (95%CI = [15.9-20.0]) and 17.1 months (95%CI = [15.0-20.9]), respectively; p < .001. Median OS were 84.0 months (95%CI = [68.3-111.0]), 50.7 months (95%CI = [44.6-59.5]) and 47.5 months (95%CI = [39.3-52.9]), respectively; p < .001. In multivariable analysis, high peritoneal cancer index score and NACT were negatively associated to DFS and OS. Surgical complexity and CC-1 were negatively associated to DFS.

CONCLUSION

PDS offered a survival gain of almost three years compared to IDS in patients with minimal or no residual disease after surgery. PDS should remain the standard of care for advanced ovarian cancer.

Laparoscopic cytoreduction After Neoadjuvant ChEmotherapy (LANCE)

BACKGROUND

Observational studies have supported the practice of offering minimally invasive interval debulking surgery after neoadjuvant chemotherapy for well-selected patients with advanced epithelial ovarian cancer. However, there are no prospective randomized data comparing the oncologic efficacy of minimally invasive and open interval debulking surgery in epithelial ovarian cancer.

PRIMARY OBJECTIVE

The primary objective of this study is to examine whether minimally invasive surgery is non-inferior to laparotomy in terms of disease-free survival in women with advanced stage epithelial ovarian cancer that responded to three or four cycles of neoadjuvant chemotherapy.

STUDY HYPOTHESIS

We hypothesize that in patients who had a complete or partial response to neoadjuvant chemotherapy, minimally invasive interval debulking surgery is not inferior to laparotomy.

TRIAL DESIGN

The Laparoscopic cytoreduction After Neoadjuvant ChEmotherapy (LANCE) trial is an international, prospective, randomized, multicenter, non-inferiority phase III trial to compare minimally invasive surgery vs laparotomy in women with advanced stage high-grade epithelial ovarian cancer that had a complete or partial response to three or four cycles of neoadjuvant chemotherapy and normalization of CA-125. The first 100 participants will be enrolled into a pilot lead-in to determine feasibility. The study will be considered feasible and will continue to Phase III under the following conditions: the accrual rate reaches at least 80% of the target rate after all pilot sites are open; the crossover rate in the minimally invasive group is less than 25%; and the difference of complete gross resection between the minimally invasive and open group is less than 20%. If the study is determined to be feasible, all remaining participants will be enrolled into the Phase III stage.

MAJOR INCLUSION/EXCLUSION CRITERIA

Patients with stage IIIC or IV high-grade epithelial ovarian, primary peritoneal or fallopian tube carcinoma who had a complete or partial response to three or four cycles of neoadjuvant chemotherapy based on imaging and normalization of CA-125 will be enrolled. Patients with evidence of tumor not amenable to minimally invasive resection on pre-operative imaging will be excluded.

PRIMARY ENDPOINT

The primary endpoint is non-inferiority of disease-free survival in minimally invasive vs laparotomic interval debulking surgery.

SAMPLE SIZE

To demonstrate non-inferiority with a margin of 33% in the hazard ratio (HR=1.33), 549 patients will be randomized.

Phase II clinical trial of metformin as a cancer stem cell-targeting agent in ovarian cancer

BACKGROUNDEpidemiologic studies suggest that metformin has antitumor effects. Laboratory studies indicate metformin impacts cancer stem-like cells (CSCs). As part of a phase II trial, we evaluated the impact of metformin on CSC number and on carcinoma-associated mesenchymal stem cells (CA-MSCs) and clinical outcomes in nondiabetic patients with advanced-stage epithelial ovarian cancer (EOC).METHODSThirty-eight patients with stage IIC (n = 1)/III (n = 25)/IV (n = 12) EOC were treated with either (a) neoadjuvant metformin, debulking surgery, and adjuvant chemotherapy plus metformin or (b) neoadjuvant chemotherapy and metformin, interval debulking surgery, and adjuvant chemotherapy plus metformin. Metformin-treated tumors, compared with historical controls, were evaluated for CSC number and chemotherapy response. Primary endpoints were (a) a 2-fold or greater reduction in aldehyde dehydrogenase-positive (ALDH+) CD133+ CSCs and (b) a relapse-free survival at 18 months of more than 50%.RESULTSMetformin was well tolerated. Median progression-free survival was 18.0 months (95% CI 14.0-21.6) with relapse-free survival at 18 months of 59.3% (95% CI 38.6-70.5). Median overall survival was 57.9 months (95% CI 28.0-not estimable). Tumors treated with metformin had a 2.4-fold decrease in ALDH+CD133+ CSCs and increased sensitivity to cisplatin ex vivo. Furthermore, metformin altered the methylation signature in CA-MSCs, which prevented CA-MSC-driven chemoresistance in vitro.CONCLUSIONTranslational studies confirm an impact of metformin on EOC CSCs and suggest epigenetic change in the tumor stroma may drive the platinum sensitivity ex vivo. Consistent with this, metformin therapy was associated with better-than-expected overall survival, supporting the use of metformin in phase III studies.TRIAL REGISTRATIONClinicalTrials.gov NCT01579812.

Electrosprayed nanoparticles of poly(p-dioxanone-co-melphalan) macromolecular prodrugs for treatment of xenograft ovarian carcinoma

Ovarian cancer is considered to be the most fatal reproductive cancers. Melphalan is used to treat ovarian cancer as an intraperitoneal chemotherapy agent. However, elucidating its pharmacokinetic behavior and preparing it for administration are challenging since it undergoes spontaneous hydrolysis. In this study, melphalan is transformed into a macromolecular prodrug by copolymerizing with p-dioxanone. The hydrophobicity of copolymer chains protects melphalan from hydrolysis. Poly(p-dioxanone-co-melphalan; PDCM) is electrosprayed and converted into nanoparticles (PDCM NPs) with diameters of ~300-350 nm to facilitate its intracellular delivery. UPLC-MS and HPLC are applied to verify and monitor the release of melphalan from PDCM NPs. PDCM NPs could suppress the proliferation of SKOV-3 cells. The IC50 of 4.3% melphalan-containing PDCM-3 NP was 70 mg/L, 72 h post administration. These suppression characteristics not only affected by the degradation and then the extracellular release of melphalan from PDCM NPs, but also the uptake via phagocytosis phenomenon in SKOV-3 cells. As revealed by flow cytometry, phagocytosis is a first-order process. Once phagocytosed, PDCM NPs are digested by lysosomes, causing a rapid release of melphalan into the cytoplasm, which ultimately causes suppression of SKOV-3 cell proliferation. Finally, the in vivo antitumor effects of PDCM NPs are verified in xenograft ovarian carcinoma. After a 20-day treatment, the tumor growth rate of the PDCM-3 NP group was (266 ± 178%) which was lower than those in the free melphalan group (367 ± 150%) and control group (648 ± 149%). Besides, significant tissue necrosis and growth suppression were observed in animals administered injections of PDCM NPs. Furthermore, the in vivo tracing results of Nile red-labeled PDCM NPs demonstrated that PDCM-3 NPs might be phagocytosed by macrophages and then taken to adjacent lymph nodes, which is a way of prevention or early treatment of lymphatic metastasis of tumors.

IP10-CDR3 Reduces The Viability And Induces The Apoptosis Of Ovarian Cancer Cells By Down-Regulating The Expression Of Bcl-2 And Caspase 3

PURPOSE

This study aimed to explore the effects of interferon-γ inducible protein 10 (IP10) and complementarity-determining region 3 (CDR3) of T cells receptor on ovarian cancer cells and the involved mechanisms.

METHODS

IP10 and CDR3 were linked with single-chain antibody (scfv) and exotoxin gene muton of Pseudomonas aeruginosa (PE40) to construct IP10-CDR3scfv and IP10-CDR3-PE40scfv. Then, we constructed pcDNA3.1-IP10-CDR3scfv and pcDNA3.1-IP10-CDR3-PE40scfv plasmids which were proved by HindIII/EcoRI digestion. SKOV3 cells and HOSEpiC cells were incubated with fluorescein isothiocyanate (FITC) labeled IP10-CDR3scfv and IP10-CDR3-PE40scfv proteins and protein levels were examined by flow cytometry. After gene transfection, SKOV3 cells were divided into four groups: Control, pcDNA3.1(+) negative control (NC) (pcDNA3.1(+) NC transfection), IP10-CDR3scfv (IP10-CDR3scfv transfection) and IP10-CDR3-PE40scfv (IP10-CDR3-PE40scfv transfection). Levels of IP10, CDR3, Caspase-3, cleaved Caspase-3 and Bcl-2 were determined by RT-PCR and Western blot. Cell viability and apoptosis were investigated by CCK-8 assay and Annexin V-FITC/PI assay, respectively.

RESULTS

The levels of FITC-labeled IP10-CDR3scfv and IP10-CDR3-PE40scfv proteins in the SKOV3+IP10-CDR3scfv group and the SKOV3+IP10-CDR3-PE40scfv group were remarkably higher than that in the SKOV3 group (P<0.05). So was the HOSEpiC related groups. There was no obvious difference in the levels of IP10, CDR3, Caspase-3, cleaved Caspase-3 and Bcl-2 between the control group and the pcDNA3.1(+) NC group. However, compared with the control group, the levels of Caspase-3 and Bcl-2 were reduced notably and the levels of IP10, CDR3 and cleaved Caspase-3 were elevated sharply in the IP10-CDR3scfv and IP10-CDR3-PE40scfv groups (P<0.05). The control group and the pcDNA3.1(+) NC group demonstrated similar cell viability and apoptosis. However, compared with the control group, cell viability in the IP10-CDR3scfv and IP10-CDR3-PE40scfv groups decreased significantly and cell apoptosis increased (P<0.05).

CONCLUSION

IP10-CDR3 could reduce the viability and induce the apoptosis of ovarian cancer cells by down-regulating the expression of Bcl-2 and Caspase-3.

Chemotherapy versus surgery for initial treatment in advanced ovarian epithelial cancer

BACKGROUND

Epithelial ovarian cancer presents at an advanced stage in the majority of women. These women require surgery and chemotherapy for optimal treatment. Conventional treatment has been to perform surgery first and then give chemotherapy. However, there may be advantages to using chemotherapy before surgery.

OBJECTIVES

To assess whether there is an advantage to treating women with advanced epithelial ovarian cancer with chemotherapy before debulking surgery (neoadjuvant chemotherapy (NACT)) compared with conventional treatment where chemotherapy follows debulking surgery (primary debulking surgery (PDS)).

SEARCH METHODS

We searched the following databases on 11 February 2019: CENTRAL, Embase via Ovid, MEDLINE (Silver Platter/Ovid), PDQ and MetaRegister. We also checked the reference lists of relevant papers that were identified to search for further studies. The main investigators of relevant trials were contacted for further information.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of women with advanced epithelial ovarian cancer (Federation of International Gynaecologists and Obstetricians (FIGO) stage III/IV) who were randomly allocated to treatment groups that compared platinum-based chemotherapy before cytoreductive surgery with platinum-based chemotherapy following cytoreductive surgery.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed risk of bias in each included trial.

MAIN RESULTS

We found 1952 potential titles, with a most recent search date of February 2019, of which five RCTs of varying quality and size met the inclusion criteria. These studies assessed a total of 1713 women with stage IIIc/IV ovarian cancer randomised to NACT followed by interval debulking surgery (IDS) or PDS followed by chemotherapy. We pooled results of the three studies where data were available and found little or no difference with regard to overall survival (OS) (1521 women; hazard ratio (HR) 1.06; 95% confidence interval (CI) 0.94 to 1.19, I2 = 0%; moderate-certainty evidence) or progression-free survival in four trials where we were able to pool data (1631 women; HR 1.02; 95% CI 0.92 to 1.13, I2 = 0%; moderate-certainty evidence). Adverse events, surgical morbidity and quality of life (QoL) outcomes were poorly and incompletely reported across studies. There may be clinically meaningful differences in favour of NACT compared to PDS with regard to serious adverse effects (SAE grade 3+). These data suggest that NACT may reduce the risk of need for blood transfusion (risk ratio (RR) 0.80; 95% CI 0.64 to 0.99; four studies,1085 women; low-certainty evidence), venous thromboembolism (RR 0.28; 95% CI 0.09 to 0.90; four studies, 1490 women; low-certainty evidence), infection (RR 0.30; 95% CI 0.16 to 0.56; four studies, 1490 women; moderate-certainty evidence), compared to PDS. NACT probably reduces the need for stoma formation (RR 0.43, 95% CI 0.26 to 0.72; two studies, 581 women; moderate-certainty evidence) and bowel resection (RR 0.49, 95% CI 0.26 to 0.92; three studies, 1213 women; moderate-certainty evidence), as well as reducing postoperative mortality (RR 0.18; 95% CI 0.06 to 0.54:five studies, 1571 women; moderate-certainty evidence). QoL on the EORTC QLQ-C30 scale produced inconsistent and imprecise results in two studies (MD -1.34, 95% CI -2.36 to -0.32; participants = 307; very low-certainty evidence) and use of the QLQC-30 and QLQC-Ov28 in another study (MD 7.60, 95% CI 1.89 to 13.31; participants = 217; very low-certainty evidence) meant that little could be inferred.

AUTHORS' CONCLUSIONS

The available moderate-certainty evidence suggests there is little or no difference in primary survival outcomes between PDS and NACT. NACT may reduce the risk of serious adverse events, especially those around the time of surgery, and the need for bowel resection and stoma formation. These data will inform women and clinicians and allow treatment to be tailored to the person, taking into account surgical resectability, age, histology, stage and performance status. Data from an unpublished study and ongoing studies are awaited.

Efficacy and safety of neoadjuvant chemotherapy versus primary debulking surgery in patients with ovarian cancer: a meta-analysis

OBJECTIVE

Neoadjuvant chemotherapy (NACT) for the treatment of epithelial ovarian cancer (EOC) has remained controversial. This meta-analysis was performed to systematically assess the efficacy and safety of NACT versus primary debulking surgery (PDS) in patients with EOC.

METHODS

PubMed, Embase, ClinicalTrials.gov, and Cochrane Library were queried to assess the therapeutic value of NACT versus PDS in EOC. Electronic databases were queried by using the keywords "ovarian cancer/neoplasms", "primary debulking surgery", and "neoadjuvant chemotherapy".

RESULTS

The available trials were pooled, and hazard ratios (HRs), relative risk ratios (RRs) and associated 95% confidence intervals (95% CIs) were determined. Sixteen trials involving 57,450 participants with EOC (NACT, 9,475; PDS, 47,975) were evaluated. We found that NACT resulted in markedly decreased overall survival than PDS in patients with EOC (HR=1.30; 95% CI=1.13-1.49; heterogeneity: p<0.001, I²=82.7%). Furthermore, our results demonstrated that the NACT group displayed increased completeness of debulking removal (RR=1.69, 95% CI=1.32-2.17; heterogeneity: p<0.001, I²=81.9%), and reduced risk of postsurgical death (RR=0.18, 95% CI=0.06-0.51; heterogeneity: p=0.698, I²=0%) and major infection (RR=0.29, 95% CI=0.17-0.51; heterogeneity: p=0.777, I²=0%) compared with patients administered PDS.

CONCLUSIONS

This meta-analysis indicated that NACT results in increased completeness of debulking removal, and reduced risk of postsurgical death and major infection compared with PDS, while PDS is associated with improved survival in comparison with NACT in EOC patients.

TRIAL REGISTRATION

PROSPERO Identifier: CRD42019120625.

Compliance to treatment guidelines and survival in women undergoing interval debulking surgery for advanced epithelial ovarian cancer

BACKGROUND

One of the primary treatment strategies for advanced epithelial ovarian cancers includes neoadjuvant chemotherapy (NACT) followed by interval debulking surgery (IDS) and adjuvant chemotherapy. Compliance to treatment is important to possibly improve outcomes.

AIM

To audit treatment compliance and its effect on overall survival (OS) and disease free survival (DFS) in women undergoing IDS.

METHODS AND RESULTS

Women diagnosed with advanced epithelial ovarian cancer undergoing IDS were included. Details of compliance to chemotherapy and surgery as per standard guidelines were assessed, and correlation with survival was studied. Reasons for protocol deviation at various levels were documented and analysed. A total of 182 patients were included. The total number of deviations was 134 with deviation at any level being 89 (48.9%) and at all levels 5%. Both patient- and treatment-related factors contributed towards deviation. Deviation or noncompliance towards treatment resulted in a significantly reduced 5-year OS (34.4% vs 58.2%; P = .001) compared with compliant patients, which retained its significance on multivariate analysis (P = .024) as well.

CONCLUSION

Deviation from treatment guidelines resulted in a significantly lower 5-year OS compared with those who remained treatment compliant. Both patient- and treatment-related factors contributed towards noncompliance and hence towards lower survival.

Systemic chemotherapy before cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) in patients with high-grade mucinous carcinoma peritonei of appendiceal origin

BACKGROUND

The role of systemic chemotherapy (SC) before cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) in appendiceal high-grade mucinous carcinoma peritonei (HGMCP) is controversial. We analyzed the effect of SC prior to CRS/HIPEC in HGMCP.

METHODS

A prospective database of CRS/HIPEC procedures for HGMCP without signet ring cells and with signet ring cells (HGMCP-S) from 1998 to 2017 was reviewed. Exclusion criteria was prior surgery >5 regions or >2 regimens of prior SC. Perioperative variables were analyzed.

RESULTS

There were 140 HGMCP/HGMCP-S identified: 64 with prior SC (preSC) and 76 without (noSC). Groups were balanced for lymph node status, complete cytoreduction rate, disease burden, complications, and postoperative SC. PreSC had more HGMCP-S, moderately/poorly differentiated histology, and longer time-to-surgery (median: 6 vs 2 months, p < 0.001). Median overall survival (mOS) was 40 vs 86 and median progression-free survival (mPFS) was 19 vs 43 months for preSC vs noSC, respectively (p = 0.006 and p = 0.007). In HGMCP-S subanalysis, mOS was 25 vs 39 and mPFS 16 vs 29 months for preSC vs noSC, respectively (p = 0.188 and p = 0.063). In moderately/poorly differentiated histology subanalysis, mOS was 38 vs 56 and mPFS 18 vs 29 months in preSC vs noSC, respectively (p = 0.199 and 0.082). Prior SC was not linked to improved OS or PFS in non-signet ring HGMCP or well-differentiated histology subanalysis.

CONCLUSION

Prior SC was not associated with less disease burden, better cytoreduction rates, or improved clinical outcomes in HGMCP, regardless of histopathologic subtype. Traditional SC agents may not be effective in HGMCP in the neoadjuvant setting.

Expression levels of MRP1, GST-π, and GSK3β in ovarian cancer and the relationship with drug resistance and prognosis of patients

Expression levels of multidrug resistance-associated protein 1 (MRP1), glutathione S-transferase π (GST-π) and glycogen synthase kinase-3β (GSK3β) were investigated in ovarian epithelial cancer and the relationship with the primary drug resistance of patients with ovarian cancer to chemotherapy. One hundred and twenty-one ovarian cancer tissue samples from patients who underwent ovarian cancer resection from January 2013 to June 2015 in Liaoning Cancer Hospital and Institute, Cancer Hospital of China Medical University were enrolled in the Experimental group, while 58 ovarian tissue samples from patients with fallopian tube obstruction but with no ovarian cancer who received surgical treatment for blocked fallopian tube were included in the Control group. After the detection of the expression levels of MRP1, GST-π, and GSK3β mRNA by RT-PCR and the analysis of related clinical pathological factors, patients in the Experimental group were divided into the Chemotherapy-sensitive and Chemotherapy-resistant groups according to the chemotherapy efficacy. Additionally, with the mean expression levels of MRP1, GST-π, and GSK3β in ovarian cancer tissues as the boundaries, the expression levels of the three genes in the Experimental group were classified into high expression and low expression. Ovarian cancer tissues had much higher expression levels of MRP1, GST-π, and GSK3β mRNA than normal ovarian tissues (P<0.05). The expression levels of MRP1, GST-π, and GSK3β mRNA in the Chemotherapy-sensitive group were significantly lower than those in the Chemotherapy-resistant group (P<0.05). Patients with high expression of MRP1, GST-π, and GSK3β mRNA had a much lower 3-year survival rate than patients with low expression of the genes (P<0.05). Highly expressed in patients with ovarian cancer, MRP1, GST-π, and GSK3β mRNA play an important role in the development and drug resistance of ovarian cancer, which ensures this study is of positive clinical guiding significance in developing proper treatment for ovarian cancer and evaluating the efficacy of chemotherapy.

The ability of whole-body SUVmax in F-18 FDG PET/CT to predict suboptimal cytoreduction during primary debulking surgery for advanced ovarian cancer

Background

The aim of this study was to (1) evaluate the ability of F-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) parameters to predict suboptimal cytoreduction and (2) to create a risk model for predicting suboptimal cytoreduction in advanced ovarian cancer. From 2011 to 2015, 51 patients underwent primary cytoreductive surgery for advanced ovarian cancer were enrolled. A residual disease with maximal diameter >  1 cm was considered a suboptimal surgical result. The SUVmax values for nine abdominal regions, the sum of 9 regional SUVmax (WB1SUVmax) and WB2SUVmax (WB1SUVmax plus SUVmax of lymph nodes) were used for PET parameter. Multiple logistic regression analysis was used to determine the predictive value of PET and clinical parameters for risk model. In addition, assessments of disease-free survival (DFS) and overall survival (OS) were performed.

Results

Seventeen of the 51 patients (33.3%) underwent suboptimal cytoreduction. The ECOG status (OR, 4.091), SUVmax of central (OR, 5.250), right upper (OR, 4.148), left upper (OR, 5.921) and WB2SUVmax (OR, 4.148) were associated with suboptimal cytoreduction. The risk model can divide the risk groups of suboptimal cytoreduction (area under the curve (AUC), 0.775; p = 0.0001). The DFS and OS in the high-risk group were significantly worse than those in the low-risk group (p = 0.0379 for DFS; p = 0.0211 for OS).

Conclusions

The presence of hypermetabolic lesions in the central, right upper, and left upper regions showed predictive value for suboptimal cytoreduction. Our risk model may be helpful for selecting patients who may show suboptimal cytoreduction.