Pressurized IntraPeritoneal Aerosol Chemotherapy (PIPAC) Applied to Platinum-Resistant Recurrence of Ovarian Tumor: A Single-Institution Experience (ID: PARROT Trial).

BACKGROUND: We aimed to investigate the therapeutic efficacy and safety of Pressurized IntraPeritoneal Aerosol Chemotherapy (PIPAC) in platinum-resistant recurrence of ovarian cancer and peritoneal carcinomatosis, while our secondary endpoint was to establish any changes in quality of life estimated via the EORTC QLQ-30 and QLQ-OV28 questionnaires. METHODS: In this monocentric, single-arm, phase II trial, women were prospectively recruited and every 28-42 days underwent courses of PIPAC with doxorubicin 2.1 mg/m2 followed by cisplatin 10.5 mg/m2 via sequential laparoscopy. RESULTS: Overall, 98 PIPAC procedures were performed on 43 women from January 2016 to January 2020; three procedures were aborted due to extensive intra-abdominal adhesions. The clinical benefit rate (CBR) was reached in 82% of women. Three cycles of PIPAC were completed in 18 women (45%), and 13 (32.5%) and 9 (22.5%) patients were subjected to one and two cycles, respectively. During two PIPAC procedures, patients experienced an intraoperative intestinal perforation. There were no treatment-related deaths. Nineteen patients showed no response according to the Peritoneal Regression Grading Score (PRGS) and 8 patients showed minor response according to the PRGS. Median time from ovarian cancer relapse to disease progression was 12 months (95% confidence interval [CI] 6.483-17.517), while the median overall survival was 27 months (95% CI 20.337-33.663). The EORTC QLQ-28 and EORTC QLQ-30 scores did not worsen during therapy. CONCLUSIONS: PIPAC seems a feasible approach for the treatment of this subset of patients, without any impact on their quality of life. Since this study had a small sample size and a single-center design, future research is mandatory, such as its application in addition to systemic chemotherapy.

Comprehensive Genomic Characterization in Ovarian Low-Grade and Chemosensitive and Chemoresistant High-Grade Serous Carcinomas.

INTRODUCTION: Genomic characterization of serous ovarian carcinoma (SOC), which includes low-grade serous carcinoma (LGSC) and high-grade serous carcinoma (HGSC), remains necessary to improve efficacy of platinum-based chemotherapy. The aim of this study was to investigate the genomic variations in these SOC groups, also in relation to chemoresponse. METHODS: Forty-five samples of SOC were retrospectively analyzed by next-generation sequencing on DNA/RNA extracts from formalin-fixed, paraffin-embedded (FFPE) tumor samples obtained at diagnosis. HGSCs were classified as platinum-resistant and platinum-sensitive. RESULTS: In the LGSC group, 44% of the carcinomas had mutually exclusive variants in the RAS/RAF pathway, while additional likely oncogenic variants in the CDKN2A, SMARCA4, and YAP1 genes were observed in the remaining LGSCs. Tumor mutation burden (TMB) was significantly lower in the intrinsically chemoresistant LGSC group than in the HGSC group. In the HGSC cohort, TP53 variants were found in 90% and homologous recombination repair (HRR) pathway variants in 41% of the neoplasms. HGSCs of the chemoresistant group without classic mutations in the HRR pathway were characterized by additional variants in FGFR2 and with an FGFR3::TACC3 fusion. In addition, HGSCs showed MYC, CCNE1, and AKT2 gains that were almost exclusively observed in the chemosensitive HGSC group. CONCLUSION: These results suggest that very low TMB and MYC, CCNE1, and AKT2 gains in SOC patients may be biomarkers related to platinum treatment efficacy. Thorough genomic characterization of SOCs prior to treatment might lead to more specific platinum-based chemotherapy strategies.

Real-world outcomes associated with bevacizumab combined with chemotherapy in platinum-resistant ovarian Cancer.

OBJECTIVES: The addition of bevacizumab to chemotherapy for platinum-resistant (PL-R) ovarian cancer (OC) improved progression-free (PFS) but not overall survival (OS) in clinical trials. We explored real-world outcomes in Ontario, Canada, and compared survival in the pre- and post-bevacizumab era. METHODS: Administrative databases were utilized to identify all patients treated with bevacizumab for PL-R OC. Time on treatment (ToT) was used as surrogate for PFS. Median OS was determined using the Kaplan-Meier method. Factors associated with ToT/OS were identified using a Cox proportional hazard model. A before and after comparative effectiveness analysis was performed to determine mOS for patients treated pre- and post-bevacizumab approval. RESULTS: From 2017 to 2019, 176 patients received bevacizumab. Median ToT was 3 months and OS was 11 months. Sixty-four percent received liposomal doxorubicin and 34% received paclitaxel. ToT (6 vs 3 months; HR 0.44; p < 0.0001) and OS (14 vs 9 months; HR 0.45; p = 0.0089) were longer with bevacizumab/paclitaxel. OS was not significantly different pre- and post-bevacizumab funding (8 vs 9 months; HR 1.01; 0.937). Median OS increased for those receiving paclitaxel (6 vs 11 months), but those in the post group were younger, more likely to have undergone primary surgery and had less co-morbidities. CONCLUSION: Real-world outcomes with bevacizumab in PL-R OC are inferior to those in the pivotal clinical trial. Survival has not significantly improved since funding became publicly available, indicating a substantial efficacy-effectiveness gap between trial and real-world outcomes. Median OS and ToT were significantly better when bevacizumab was given with paclitaxel.

Durvalumab with or without tremelimumab plus chemotherapy in HRR non-mutated, platinum-resistant ovarian cancer (KGOG 3045): A phase II umbrella trial.

AIM: We investigated the efficacy and safety of durvalumab (D) with or without tremelimumab (T) in addition to single-agent chemotherapy (CT) in patients with platinum-resistant recurrent ovarian cancer (PROC) lacking homologous recombination repair (HRR) gene mutations. PATIENTS AND METHODS: KGOG 3045 was an open-label, investigator-initiated phase II umbrella trial. Patients with PROC without HRR gene mutations who had received ≥2 prior lines of therapy were enrolled. Patients with high PD-L1 expression (TPS ≥25%) were assigned to arm A (D + CT), whereas those with low PD-L1 expression were assigned to arm B (D + T75 + CT). After completing arm B recruitment, patients were sequentially assigned to arms C (D + T300 + CT) and D (D + CT). RESULTS: Overall, 58 patients were enrolled (5, 18, 17, and 18 patients in arms A, B, C, and D, respectively). The objective response rates were 20.0, 33.3, 29.4, and 22.2%, respectively. Grade 3-4 treatment-related adverse events were observed in 20.0, 66.7, 47.1, and 66.7 of patients, respectively, but were effectively managed. Multivariable analysis demonstrated that adding T to D + CT improved progression-free survival (adjusted HR, 0.435; 95% CI, 0.229-0.824; P = 0.011). Favorable response to chemoimmunotherapy was associated with MUC16 mutation (P = 0.0214), high EPCAM expression (P = 0.020), high matrix remodeling gene signature score (P = 0.017), and low FOXP3 expression (P = 0.047). Patients showing favorable responses to D + T + CT exhibited significantly higher EPCAM expression levels (P = 0.008) and matrix remodeling gene signature scores (P = 0.031) than those receiving D + CT. CONCLUSIONS: Dual immunotherapy with chemotherapy showed acceptable response rates and tolerable safety in HRR non-mutated PROC, warranting continued clinical investigation.

Efficacy and safety of VEGF/VEGFR inhibitors for platinum-resistant ovarian cancer: a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Almost all patients with ovarian cancer will experience relapse and eventually develop platinum-resistant. The poor prognosis and limited treatment options have prompted the search for novel approaches in managing platinum-resistant ovarian cancer (PROC). Therefore, a meta-analysis was conducted to evaluate the efficacy and safety of combination therapy with vascular endothelial growth factor (VEGF) /VEGF receptor (VEGFR) inhibitors for PROC. METHODS: A comprehensive search of online databases was conducted to identify randomized clinical trials published until December 31, 2022. Pooled hazard ratios (HR) was calculated for overall survival (OS) and progression-free survival (PFS), while pooled odds ratio (OR) was calculated for objective response rate (ORR) and treatment-related adverse events (TRAEs). Subgroup analysis was further performed to investigate the source of heterogeneity. RESULTS: In total, 1097 patients from eight randomized clinical trials were included in this meta-analysis. The pooled HRs of OS (HR = 0.72; 95% CI: 0.62-0.84, p < 0.0001) and PFS (HR = 0.52; 95% CI: 0.45-0.59, p < 0.0001) demonstrated a significant prolongation in the combination group compared to chemotherapy alone for PROC. In addition, combination therapy demonstrated a superior ORR compared to monotherapy (OR = 2.34; 95%CI: 1.27-4.32, p < 0.0001). Subgroup analysis indicated that the combination treatment of VEGF/VEGFR inhibitors and chemotherapy was significantly more effective than monochemotherapy in terms of OS (HR = 0.71; 95% CI: 0.61-0.84, p < 0.0001), PFS (HR = 0.49; 95% CI: 0.42-0.57, p < 0.0001), and ORR (OR = 2.97; 95% CI: 1.89-4.67, p < 0.0001). Although the combination therapy was associated with higher incidences of hypertension, mucositis, proteinuria, diarrhea, and hand-foot syndrome compared to monochemotherapy, these toxicities were manageable and well-tolerated. CONCLUSIONS: The meta-analysis demonstrated that combination therapy with VEGF/VEGFR inhibitors yielded better clinical outcomes for patients with PROC compared to monochemotherapy, especially when combined with chemotherapy. This analysis provides more treatment options for patients with PROC. SYSTEMATIC REVIEW REGISTRATION: [ https://www.crd.york.ac.uk/PROSPERO ], Prospective Register of Systematic Reviews (PROSPERO), identifier: CRD42023402050.

The efficacy, safety, and beneficiary population of angiogenesis inhibitor apatinib plus chemotherapy in recurrent platinum-resistant ovarian cancer patients: A comparative cohort study.

AIM: Angiogenesis inhibitor apatinib targets vascular endothelial growth factor receptors and improves the outcomes of patients with gynecologic malignancy. This study aimed to evaluate the efficacy and safety of angiogenesis inhibitor apatinib plus chemotherapy in recurrent platinum-resistant ovarian cancer (RPR-OC) patients. METHODS: This study retrieved 67 RPR-OC patients who received apatinib plus chemotherapy or chemotherapy alone and divided them into apatinib + chemo (N = 30) and chemo alone (N = 37) groups according to the actual medication. RESULTS: Objective response rate (36.7% vs. 16.2%, p = 0.056) and disease control rate (80.0% vs. 59.5%, p = 0.072) showed an increased trend in apatinib + chemo group versus chemo alone group. The progression-free survival (PFS) (p = 0.010) and overall survival (OS) (p = 0.042) were prolonged in apatinib + chemo group versus chemo alone group. The median (95%confidence interval [CI]) PFS was 5.9 (5.5-6.3) months in apatinib + chemo group and 3.8 (2.0-5.6) months in chemo alone group. The median (95%CI) OS was 20.5 (16.5-24.5) months in apatinib + chemo group and 13.6 (8.6-18.6) months in chemo alone group. Apatinib plus chemotherapy was independently related with better PFS (hazard ratio [HR]: 0.354, p < 0.001) and OS (HR: 0.116, p < 0.001). Subgroup analyses indicated that patients with a more serious disease condition might benefit more from apatinib plus chemotherapy. No difference was found in adverse events of all grade or grade ≥3 between the two groups (all p > 0.05). CONCLUSION: Angiogenesis inhibitor apatinib plus chemotherapy shows better treatment efficacy than chemotherapy alone with controllable safety profile in RPR-OC patients.

Randomized, two-arm, noncomparative phase 2 study of olaparib plus cediranib or durvalumab in HRR-mutated, platinum-resistant ovarian cancer: A substudy of KGOG 3045.

Choosing an optimal concomitant drug for combination with poly-ADP ribose polymerase (PARP) inhibitor based on patient-specific biomarker status may help increase to improve treatment efficacy in patients with ovarian cancer. However, the efficacy and safety of different PARP inhibitor-based combinations in patients with homologous recombination repair (HRR) mutations have not been evaluated in ovarian cancer. In this sub-study of Korean Gynecologic Oncology Group (KGOG) 3045, we compared the efficacy and safety of two olaparib-based combinations and biomarkers of patients with platinum-resistant ovarian cancer with HRR gene mutations. Patients were randomized to receive either olaparib (200 mg twice a day) + cediranib (30 mg daily) (Arm 1, n = 16) or olaparib (300 mg) + durvalumab (1,500 mg once every 4 weeks) (Arm 2, n = 14). The objective response rates for Arm 1 and Arm 2 were 50.0% and 42.9%, respectively. Most patients (83.3%) had BRCA mutations, which were similarly distributed between arms. Grade 3 or 4 treatment-related adverse events were observed in 37.5% and 35.7% of the patients, respectively, but all were managed properly. A high vascular endothelial growth factor signature was associated with favorable outcomes in Arm 1, whereas immune markers (PD-L1 expression [CPS ≥10], CD8, neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio) were associated with favorable outcomes in Arm 2. The activation of homologous recombination pathway upon disease progression was associated with poor response to subsequent therapy. Based on comprehensive biomarker profiling, including immunohistochemistry, whole-exome and RNA sequencing and whole blood-based analyses, we identified biomarkers that could help inform which of the two combination strategies is appropriate given a patient's biomarker status. Our findings have the potential to improve treatment outcome for patients with ovarian cancer in the PARP inhibitor era.

Immunotherapy May Improve Tumor Sensitivity to Palliative Chemotherapy in Platinum Resistant Ovarian Cancer.

Ovarian cancer is the second most common gynecologic cancer in the US and ranks among the top 10 causes of female cancer-related deaths. Platinum-resistant disease carries a particularly poor prognosis and leaves patients with limited remaining therapeutic options. Patients with platinum-resistant disease have significantly lower response rates to additional chemotherapy, with estimates as low as 10%-25%. We hypothesize that in patients with platinum-resistant ovarian cancer, treatment with immunotherapy followed by cytotoxic chemotherapy with antiangiogenic therapy results in prolonged survival without compromising quality of life. Our experience of 3 patients with recurrent, metastatic platinum-resistant ovarian cancer treated with immunotherapy followed by anti-angiogenic treatment plus chemotherapy resulted in progression-free survival durations significantly above previously published averages. Further studies evaluating the role of immunotherapy followed by chemotherapy in combination with drugs targeting angiogenesis are needed and may provide a long-sought after breakthrough for advancing survival in platinum-resistant ovarian cancer.

Targeting RAS-ERK pathway alterations with MEK inhibitors to improve chemosensitivity in high grade serous ovarian cancers.

OBJECTIVE: Assess if MEK inhibitor blockade of RAS-ERK pathway adaptive response in high grade serous ovarian cancers (HGSOC) improves platinum sensitivity. METHODS: Three HGSOC cell lines and three patient derived organoid (PDOs) samples from ascites of platinum resistant HGSOC patients were collected. Cell lines and PDOs were exposed to carboplatin and MEK inhibitors cobimetinib or trametinib. Cytotoxic effects of MEK inhibitors alone or combined with carboplatin were established. Western blots demonstrated RAS-ERK pathway blockage after MEK inhibitor treatment. RNA sequencing assessed gene expression after MEK inhibitor treatment. Cell line NF1 gene knockdown was performed with corresponding chemosensitivity levels. RESULTS: High carboplatin IC50 levels indicated platinum resistance in cell lines and PDOs. Cobimetinib induced cytotoxicity in cell lines and PDOs, while trametinib was less effective. Western blot confirmed MEK-ERK pathway blockage at minimal concentrations of MEK inhibitors in cell lines and PDOs. Phosphorylated-ERK levels of untreated cells indicated higher levels of RAS-ERK pathway activation in OVSAHO and OVCAR7 compared to OVCAR3. OVSAHO harbors a NF1 mutation and had highest levels of RAS-ERK activation. Cotreatment with carboplatin and MEK inhibitors showed varying synergistic cytotoxic effects at different combinations. Synergistic effect was most prominent in the OVSAHO carboplatin and cobimetinib combination. RNA sequencing identified downregulation of c-MYC and FOXM1 gene expression after MEK inhibitor treatment. NF1 gene knockdown showed an acquired increased IC50 compared to parental cells. CONCLUSION: MEK inhibitors block RAS-ERK pathways in platinum resistant HGSOC cells and PDOs. MEK inhibitors with carboplatin have select synergistic effects which may indicate a strategy to improve platinum sensitivity.

Safety and efficacy of mirvetuximab soravtansine, a folate receptor alpha (FRα)-targeting antibody-drug conjugate (ADC), in combination with bevacizumab in patients with platinum-resistant ovarian cancer.

PURPOSE: Evaluate the antitumor activity and safety profile of the combination of mirvetuximab soravtansine and bevacizumab in patients with platinum-resistant ovarian cancer. METHODS: Patients with recurrent epithelial ovarian, fallopian tube, or primary peritoneal cancer, whose most recent platinum-free interval was ≤6 months, were administered mirvetuximab soravtansine (6 mg/kg adjusted ideal body weight) and bevacizumab (15 mg/kg), intravenously, once every 3 weeks. Eligibility included FRα expression by immunohistochemistry (IHC; ≥25% of cells with ≥2+ intensity). Prior bevacizumab and/or PARP inhibitor (PARPi) treatment were permitted. The primary endpoint was confirmed objective response rate (ORR). Secondary endpoints included duration of response (DOR), progression-free survival (PFS), and safety. RESULTS: Ninety-four patients received combination treatment with mirvetuximab soravtansine and bevacizumab. Median age was 62 years (range, 39-81). Fifty-two percent had ≥3 prior therapies; 59% had prior bevacizumab; and 27% had prior PARPi. ORR was 44% (95% CI 33, 54) with 5 complete responses, median DOR 9.7 months (95% CI 6.9, 14.1), and median PFS 8.2 months (95% CI 6.8, 10.0). Treatment-related adverse events were consistent with the profiles of each agent, with the most common being blurred vision (all grades 57%; grade 3, 1%), diarrhea (54%; grade 3, 1%), and nausea (51%; grade 3, 1%). CONCLUSION: The mirvetuximab soravtansine plus bevacizumab doublet is an active and well-tolerated regimen in patients with FRα-expressing platinum-resistant ovarian cancer. Promising activity was observed for patients regardless of level of FRα expression or prior bevacizumab. These data underscore the potential for mirvetuximab soravtansine as the combination partner of choice for bevacizumab in this setting.

Niraparib and dostarlimab for the treatment of recurrent platinum-resistant ovarian cancer: results of a Phase II study (MOONSTONE/GOG-3032).

OBJECTIVE: This study assessed the efficacy, safety, and health-related quality of life (HRQoL) of the treatment regimen of dostarlimab, a programmed death-1 inhibitor, combined with niraparib, a poly (ADP-ribose) polymerase inhibitor, in patients with BRCA wild type (BRCAwt) recurrent platinum-resistant ovarian cancer (PROC) who had previously received bevacizumab treatment. METHODS: This Phase II, open-label, single-arm, multicenter study, conducted in the USA, enrolled patients with recurrent PROC to receive niraparib and dostarlimab until disease progression or unacceptable toxicity (up to 3 years). A preplanned interim futility analysis was performed after the first 41 patients had undergone ≥1 radiographic evaluation (approximately 9 weeks from the first treatment). RESULTS: The prespecified interim futility criterion was met and the study was therefore terminated. For the 41 patients assessed, the objective response rate (ORR) was 7.3% (95% confidence interval: 1.5-19.9); no patients achieved a complete response, 3 patients (7.3%) achieved a partial response (duration of response; 3.0, 3.8, and 9.2 months, respectively), and 9 patients (22.0%) had stable disease. In total, 39 patients (95.1%) experienced a treatment-related adverse event, but no new safety issues were observed. HRQoL, assessed using FOSI, or Functional Assessment of Cancer Therapy - Ovarian Symptom Index scores, worsened over time compared with baseline scores. CONCLUSIONS: The study was terminated due to the observed ORR at the interim futility analysis. This highlights a need for effective therapies in treating patients with recurrent BRCAwt PROC.

ARTISTRY-7: phase III trial of nemvaleukin alfa plus pembrolizumab vs chemotherapy for platinum-resistant ovarian cancer.

Standard single-agent nonplatinum chemotherapy provides only modest benefit in a small proportion of patients with platinum-resistant/-refractory ovarian cancer, with objective response rates of 6-20% and progression-free survival of ≈3-4 months. Nemvaleukin alfa (nemvaleukin, ALKS 4230) is a novel cytokine designed to capture and expand the therapeutic potential of high-dose interleukin-2 (IL-2) while mitigating its associated toxicity issues. Nemvaleukin preferentially activates cytotoxic CD8+ T cells and natural killer cells with minimal, non-dose-dependent effects on CD4+ regulatory T cells. The global, randomized, open-label, phase III ARTISTRY-7 trial will compare efficacy and safety of nemvaleukin plus pembrolizumab with chemotherapy in patients with platinum-resistant ovarian cancer. The primary end point is investigator-assessed progression-free survival. Clinical Trial Registration: GOG-3063; ENGOT-OV68; NCT05092360 (ClinicalTrials.gov).

In many patients with ovarian cancer who are treated with platinum-based chemotherapy, the tumor comes back after a few months and fails to respond to repeated treatment. This type of disease is called platinum-resistant ovarian cancer (PROC). Researchers are searching for new medicines to help more patients with PROC. One treatment approach that has shown promise in different cancers is called immunotherapy. These medicines work by helping the body's immune system attack cancer cells. One of the immunotherapies being studied is called nemvaleukin. It is designed to trigger specific immune responses that may result in the immune system attacking cancer cells while potentially avoiding other immune responses that can block the attack or cause certain unwanted side effects. Nemvaleukin is being studied in a variety of cancer types. In a worldwide clinical trial called ARTISTRY-7, researchers are investigating how nemvaleukin works in patients with PROC when given with another immunotherapy called pembrolizumab. Patients who participate in this trial will be randomly assigned to one of four treatment groups: the combination of nemvaleukin and pembrolizumab, nemvaleukin by itself, pembrolizumab by itself, or a type of chemotherapy selected by the treating physician. The main purpose of ARTISTRY-7 is to understand whether the combination of nemvaleukin and pembrolizumab helps patients with PROC live longer without their cancer getting worse. At the time of this writing, ARTISTRY-7 is open for new patients to join.

Heterogeneous effects of cytotoxic chemotherapies for platinum-resistant ovarian cancer.

BACKGROUND: Single-agent chemotherapy with or without bevacizumab (Bev) is a standard therapy for platinum-resistant ovarian cancer (PR-OC). However, there is a lack of literature on chemotherapy agent selection in heterogenous PR-OC. Therefore, we aimed to clarify the heterogeneous treatment effects of each chemotherapy agent. METHODS: Patients who underwent single-drug chemotherapy agents or Bev combination therapy for PR-OC between January 2009 and June 2022 were included in this study. We assessed the impact of each chemotherapy agent on the time to treatment failure (TTF) according to histological type, platinum-free interval (PFI), and Bev usage. RESULTS: A total of 158 patients received 343 different chemotherapy regimens. In patients with clear cell carcinoma/mucinous carcinoma (CC/MC), gemcitabine (GEM) had the strongest effect with a median TTF of 5.3 months, whilst nedaplatin (NDP) had the lowest effect with a median TTF of 1.4 months. In contrast, in the non-CC/MC group, irinotecan (CPT-11) and NDP had a better TTF than GEM and pegylated liposomal doxorubicin (PLD). There were notable differences in the treatment efficacy of NDP according to PFI. Specifically, NDP prolonged the TTF in patients with a PFI ≥ 3 months. Compared with GEM alone, GEM + Bev tended to prolong the TTF more effectively; however, an additive effect was not observed with PLD + Bev. CONCLUSIONS: This study demonstrated that the effect of chemotherapy agents differed according to the tumor and background characteristics of the patient. Our findings will improve selection of effective therapies for patients with PR-OC by considering their background characteristics.

Cytoreductive surgery is feasible in patients with limited regional platinum-resistant recurrent ovarian cancer.

INTRODUCTION: To evaluate the efficacy of cytoreductive surgery versus chemotherapy for the treatment of limited regional, platinum-resistant ovarian cancer (PROC). MATERIALS AND METHODS: The clinical records of all patients with PROC treated in our center between March 2015 and March 2022 were retrospectively reviewed. We compared the oncology outcomes of patients who received cytoreduction or chemotherapy alone at relapse and presented information about postoperative adjuvant chemotherapy. RESULTS: Among 52 patients with limited regional recurrence, 40.4% (21/52) underwent cytoreduction because of platinum resistance, and 59.6% (31/52) received chemotherapy alone. No residual disease (R0) was achieved in 20 patients (95.2%). The severe morbidity rate within 30 days after the surgery was 15%. The median follow-up was 70.6 months. Compared with the chemotherapy alone group, the surgery group with R0 had better progression-free survival (PFS) (10.6 vs. 5.1 months; hazard ratio (HR) = 0.421; P = 0.0035) and post-relapse survival (PRS) (32.6 vs. 16.3 months; HR = 0.478; P = 0.047), but there was no difference in overall survival (OS) between the two groups. Laparoscopy is associated with lesser intraoperative blood loss with no differences in survival and postoperative complications compared to the open approach (P = 0.0042). Subgroup survival analysis showed that compared with chemotherapy alone, surgery prolonged PFS in patients regardless of tumor size (greater than or equal to 4 cm or less). Surgery group patients who achieved R0 had an objective response rate (ORR) of 36.8% (7/19), among whom 40% (4/10) received platinum rechallenge chemotherapy and 33.3% (3/9) were administered non-platinum chemotherapy. CONCLUSION: When well-selected PROC patients with limited regional recurrence achieved R0, their outcomes were superior to those of patients who received only chemotherapy with an acceptable morbidity rate. Laparoscope technology could be a reliable alternative surgical approach. The reintroduction of platinum agents may be considered following surgery. Further analyses in a larger population are warranted to elucidate the risks and benefits of this surgery and adjuvant chemotherapy strategy.

Efficacy and safety of apatinib combined with liposomal doxorubicin or paclitaxel versus liposomal doxorubicin or paclitaxel monotherapy in patients with recurrent platinum-resistant ovarian cancer.

AIM: Apatinib is an effective treatment for patients with gynecological cancers. This study aimed to further explore the efficacy and safety of apatinib plus chemotherapy in patients with recurrent platinum-resistant ovarian cancer (PROC). METHODS: Totally, 105 patients with recurrent PROC receiving apatinib plus chemotherapy (N = 51) and chemotherapy alone (N = 54) were retrospectively enrolled in this cohort study. RESULTS: Objective response rate (37.3% vs. 14.8%) (p = 0.009) and disease control rate (80.4% vs. 61.1%) (p = 0.030) were increased in the apatinib plus chemotherapy group versus the chemotherapy group. The median (95% confidence interval [CI]) progression-free survival (PFS) and overall survival (OS) were 5.5 (3.4-7.6) and 21.4 (16.2-26.6) months in the apatinib plus chemotherapy group, and they were 3.8 (3.0-4.6) and 14.8 (11.9-17.7) months in the chemotherapy group. Meanwhile, the Kaplan-Meier curves revealed that PFS (p = 0.008) and OS (p = 0.012) were prolonged in the apatinib plus chemotherapy group versus the chemotherapy group. This finding was confirmed by multivariate Cox's proportional regression analyses: enter method (hazard ratio [HR] = 0.515, p = 0.007 for PFS; HR = 0.222, p < 0.001 for OS) and step-forward method (HR = 0.608, p = 0.019 for PFS; HR = 0.346, p = 0.001 for OS). Additionally, the incidence of hypertension was increased in the apatinib plus chemotherapy group versus the chemotherapy group (p = 0.038), while others were not different between the two groups (all p > 0.05). Grades 3 and 4 adverse events were neutropenia, hypertension, leukopenia, hand-foot syndrome, nausea and vomiting, fatigue, thrombocytopenia, and anemia in the apatinib plus chemotherapy group. CONCLUSION: Apatinib combined with chemotherapy is a superior choice over chemotherapy alone for recurrent PROC management.

New approaches for targeting platinum-resistant ovarian cancer.

Platinum is the backbone of systemic treatment in ovarian cancer and development of platinum resistance is associated with poor survival. Here, we perform a comprehensive review of the literature regarding resistance mechanisms and advances in therapy for platinum resistant ovarian cancer, with a focus on high-grade serous carcinoma. Platinum resistance can be intrinsic or acquired. Resistance mechanisms are complex and diverse. Intracellular mechanisms include restoration of homologous recombination repair, reduced intracellular accumulation of platinum, blocked cellular replication and inhibition of apoptosis. These act in concert with immunosuppressive, angiogenic and stromal changes in the tumour microenvironment to drive treatment resistance. Current molecular stratification lacks prognostic and predictive validity, limited in part by the extreme genomic complexity of high-grade serous ovarian cancer. Clinical trials represent an important option for patients as standard of care treatment options have limited efficacy. The most promising trials appear to focus on rational combinations of chemotherapy, immunotherapy, anti-angiogenics, PARP inhibitors, targeted therapy and/or antibody-drug conjugates. Resistance mechanisms are multifactorial with capacity to evolve over time, making clinical detection challenging. It is increasingly apparent that clinical trials must incorporate correlative studies to elucidate predictive biomarkers. They must also adopt endpoints that can appropriately measure benefit for palliative treatments. Future research must aim to deepen our understanding of the biology of this disease, and deliver meaningful benefit in terms of improved quality of life and overall survival for women with platinum resistant ovarian cancer.

Revisiting antibody-drug conjugates and their predictive biomarkers in platinum-resistant ovarian cancer.

Until to date, platinum derived drugs are still the backbone of treating ovarian cancer (OC). Most patients treated with platinum-based chemotherapy develop resistance during the course of their management. The treatment of platinum-resistant ovarian cancer (PROC) is challenging. Few therapeutic options are available for patients with this aggressive disease. Besides, there are liminal advances regarding new anticancer drugs as well as validated predictive biomarkers of clinical outcomes in this setting. The enrollment of PROC patients in interventional studies is limited as compared to newly launched clinical trials for platinum-sensitive OC. Enthusiastically, the emergence of antibody-drug conjugates (ADCs) has provided promising findings for further clinical development in PROC. ADCs have the advantage to selectively deliver cytotoxic drugs to cancer cells expressing several of antigens using specific monoclonal antibodies based on the concept of immune bioconjugation. This innovative class of therapeutics showed encouraging early signs of clinical efficacy in PROC particularly mirvetuximab soravtansine that has been successfully introduced into three randomized and controlled phase III studies. In this review, the evidence from clinical trials supporting the development of ADCs targeting folate receptor alpha, sodium-dependent phosphate transporter 2B, dipeptidase 3, mesothelin, mucin 16, and tissue factor using various cytotoxic payloads in PROC is reviewed.

The role of surgery in platinum-resistant ovarian cancer: A call to the scientific community.

In the last decade, a growing attention has been focused on identifying effective therapeutic strategies also in the orphan clinical setting of women with platinum-resistant disease. In this context, secondary cytoreductive surgery (SCS) remains a potential approach only in women with platinum sensitive relapse, but experimental data have been published supporting the role of SCS also in patients with platinum-resistant recurrence. In particular, surgery is emerging as a potential option in specific subgroups of women, such as those patients with low-grade serous histology, or low-volume relapse with disease located in the so-called pharmacological sanctuaries. Furthermore, contrasting evidences have suggested a potential role in this clinical setting of SCS combined with intraperitoneal hyperthermic chemotherapy. In this complex scenario we review here the available evidences regarding the role surgery in ovarian cancer patients with platinum resistant disease, trying also to understand which patients may benefit from this challenging, experimental approach.

Genomic profiling of platinum-resistant ovarian cancer: The road into druggable targets.

Ovarian cancer is the most lethal gynecologic cancer. High-grade serous carcinoma (HGSC) is the most frequent histologic subtype and while it is a highly platinum-sensitive cancer at initial treatment, nearly 90 % of stage IIIC patients recur in 5 years and eventually become resistant to platinum treatment. Historically, the definition of platinum-resistant disease is based on the time interval between last platinum therapy and recurrence shorter than 6 months. Nowadays the use of sophisticated imaging techniques and serum markers to detect recurrence makes the accuracy of this clinical definition less clear and even more debatable as we begin to better understand the molecular landscape of HGSC and markers of platinum resistance and sensitivity. HGSC is characterized by a low frequency of recurrent mutations, great genomic instability with widespread copy number variations, universal TP53 mutations, and homologous recombination deficiency in more than 50 % of cases. Platinum agents form DNA adducts and intra- and inter-strand cross-links in the DNA. Most of DNA repair pathways are involved at some point in the repair of platinum induced DNA damaging, most notably homologous recombination, Fanconi Anemia, and nucleotide excision repair pathways. Mechanisms of platinum resistance are related mostly to the limitation of platinum-DNA adduct formation by changing cellular pharmacology, and to the prevention of cell death after DNA damage due to alterations in DNA repair pathways and cell cycle regulation. Understanding these mechanisms of sensitivity and resistance may help to define the utility of platinum re-challenge in each situation and guide new therapeutic opportunities. Moreover, the discovery of mechanisms of synthetic lethality related to alterations in DNA repair and cell cycle regulation pathways has opened up a new avenue for drug therapy in the last decade. In the present article, we review pathways involved in platinum-induced DNA damage repair and their relationship with genomic alterations present in HGSC. Moreover, we report new treatment strategies that are underway to target these alterations.

Challenges for immunotherapy for the treatment of platinum resistant ovarian cancer.

Platinum resistant ovarian cancer, usually defined as progression occurring within 6 months after completing platinum-based therapy, is a heterogeneous disease with poor prognosis and short survival (less than 18 months). It is typically considered as a "cold tumor", characterized by reduced infiltration by immune cells, particularly CD8+ T cells. Response rate to anti-PD1/PD-L1 monotherapy is low, not exceeding 8%. Multiple therapeutic strategies are currently investigated in order to increase response rates to anti-PD1/PD-L1 through adding chemotherapy, anti-angiogenic agents, DNA damage (PARP inhibitors, cyclophosphamide and/or radiotherapy) or other immune checkpoint inhibitors (CTLA-4, etc.). Ovarian clear cell carcinoma, a rare histotype characterized by primary platinum-resistance, recently showed anecdotal but promising response rates to immune checkpoint blockade. Other immunotherapeutic approaches such as adoptive T cell therapy, vaccines and targeting myeloid immune checkpoints like "don't eat me" signal CD47 are currently investigated. Each approach faces distinct challenges that will be reviewed here. Robust immunogenomics studies conducted in parallel of the ongoing trials will help into refining optimal immunotherapy combination for this lethal disease and identify predictive biomarkers.