Homologous Recombination Deficiency Associated With Response to Poly (ADP-ribose) Polymerase Inhibitors in Ovarian Cancer Patients: The First Real-World Evidence From China

PARPis response and outcome of ovarian cancer patients with BRCA1/2 germline mutation and a history of breast cancer

OBJECTIVE

The aim of this study was to determine the poly (ADP-ribose) polymerase inhibitors (PARPis) response and outcome of ovarian cancer (OC) patients with BRCA1/2 germline mutation and a history of breast cancer (BC).

METHODS

Thirty-nine OC patients with BRCA1/2 germline mutation and a history of BC were included. The clinicopathological characteristics, PARPis response and prognosis were analyzed.

RESULTS

The median interval from BC to OC diagnosis was 115.3 months (range=6.4-310.1). A total of 38 patients (38/39, 97.4%) received platinum-based chemotherapy after surgical removal. The majority of these patients were reported to be platinum sensitive (92.1%, 35/38). 21 patients (53.8%) received PARPis treatment with 16 patients (76.2%) for maintenance treatment and 5 patients (5/21, 23.8%) for salvage treatment. The median duration for PARPis maintenance and salvage treatment was 14.9 months (range=2.0-56.9) and 8.2 months (range=5.2-20.7), respectively. In the entire cohort, 5-year progression-free survival (PFS) and overall survival (OS) rate was 33.1% and 78.9%, respectively. Patients with BRCA1 mutation had a non-significantly worse 5-year PFS (28.6% vs. 45.8%, p=0.346) and 5-year OS (76.9% vs. 83.3%, p=0.426) than those with BRCA2 mutation. In patients with stage III-IV (n=31), first line PARPis maintenance treatment associated with a non-significantly better PFS (median PFS: NR vs. 22.4 months; 5-year PFS: 64.3% vs. 21.9%, p=0.096).

CONCLUSION

The current study shows that these patients may have a good response to platinum-based chemotherapy and a favorable survival. And these patients can benefit from PARPis treatment and will likely be suitable candidates for PARPis.

Genomic alteration discordance in the paired primary-recurrent ovarian cancers: based on the comprehensive genomic profiling (CGP) analysis

PURPOSE

Ovarian cancer (OC) is characterized by a high recurrence rate, and homologous recombination deficiency (HRD) is an important biomarker in the clinical management of OC. We investigated the differences in clinical genomic profiles between the primary and platinum-sensitive recurrent OC (PSROC), focusing on HRD status.

MATERIALS AND METHODS

A total of 40 formalin-fixed paraffin-embedded (FFPE) tissues of primary tumors and their first platinum-sensitive recurrence from 20 OC patients were collected, and comprehensive genomic profiling (CGP) analysis of FoundationOne®CDx (F1CDx) was applied to explore the genetic (dis)similarities of the primary and recurrent tumors.

RESULTS

By comparing between paired samples, we found that genomic loss of heterozygosity (gLOH) score had a high intra-patient correlation (r2 = 0.79) and that short variants (including TP53, BRCA1/2 and NOTCH1 mutations), tumor mutational burden (TMB) and microsatellite stability status remained stable. The frequency of (likely) pathological BRCA1/2 mutations was 30% (12/40) in all samples positively correlated with gLOH scores, but the proportion of gLOH-high status (score > 16%) was 50% (10/20) and 55% (11/20) in the primary and recurrent samples, respectively. An additional 20% (4/20) of patients needed attention, a quarter of which carried the pathological BRCA1 mutation but had a gLOH-low status (gLOH < 16%), and three-quarters had different gLOH status in primary-recurrent pairs. Furthermore, we observed the PSROC samples had higher gLOH scores (16.1 ± 9.24 vs. 19.4 ± 11.1, p = 0.007), more CNVs (36.1% vs. 15.1% of discordant genomic alternations), and significant enrichment of altered genes in TGF-beta signaling and Hippo signaling pathways (p < 0.05 for all) than their paired primaries. Lastly, mutational signature and oncodrive gene analyses showed that the computed mutational signature similarity in the primary and recurrent tumors were best matched the COSMI 3 signature (Aetiology of HRD) and had consistent candidate cancer driver genes of MSH2, NOTCH1 and MSH6.

CONCLUSION

The high genetic concordance of the short variants remains stable along OC recurrence. However, the results reveal significantly higher gLOH scores in the recurrent setting than in paired primaries, supporting further clinically instantaneity HRD assay strategy.

Exploratory biomarker analysis in the phase III L-MOCA study of olaparib maintenance therapy in patients with platinum-sensitive relapsed ovarian cancer

BACKGROUND

The prospective phase III multi-centre L-MOCA trial (NCT03534453) has demonstrated the encouraging efficacy and manageable safety profile of olaparib maintenance therapy in the Asian (mainly Chinese) patients with platinum-sensitive relapsed ovarian cancer (PSROC). In this study, we report the preplanned exploratory biomarker analysis of the L-MOCA trial, which investigated the effects of homologous recombination deficiency (HRD) and programmed cell death ligand 1 (PD-L1) expression on olaparib efficacy.

METHODS

HRD status was determined using the ACTHRD assay, an enrichment-based targeted next-generation sequencing assay. PD-L1 expression was assessed by SP263 immunohistochemistry assay. PD-L1 expression positivity was defined by the PD-L1 expression on ≥ 1% of immune cells. Kaplan-Meier method was utilised to analyse progression-free survival (PFS).

RESULTS

This exploratory biomarker analysis included 225 patients and tested HRD status [N = 190; positive, N = 125 (65.8%)], PD-L1 expression [N = 196; positive, N = 56 (28.6%)], and BRCA1/2 mutation status (N = 219). The HRD-positive patients displayed greater median PFS than the HRD-negative patients [17.9 months (95% CI: 14.5-22.1) versus 9.2 months (95% CI: 7.5-13.8)]. PD-L1 was predominantly expressed on immune cells. Positive PD-L1 expression on immune cells was associated with shortened median PFS in the patients with germline BRCA1/2 mutations [14.5 months (95% CI: 7.4-18.2) versus 22.2 months (95% CI: 18.3-NA)]. Conversely, positive PD-L1 expression on immune cells was associated with prolonged median PFS in the patients with wild-type BRCA1/2 [20.9 months (95% CI: 13.9-NA) versus 8.3 months (95% CI: 6.7-13.8)].

CONCLUSIONS

HRD remained an effective biomarker for enhanced olaparib efficacy in the Asian patients with PSROC. Positive PD-L1 expression was associated with decreased olaparib efficacy in the patients with germline BRCA1/2 mutations but associated with improved olaparib efficacy in the patients with wild-type BRCA1/2.

TRIAL REGISTRATION

NCT03534453. Registered at May 23, 2018.

Olaparib plus bevacizumab as a first-line maintenance treatment for patients with advanced ovarian cancer by molecular status: an updated PAOLA-1 based cost-effectiveness analysis

OBJECTIVE

The PAOLA-1 trial (NCT02477644) reported final survival benefit associated with olaparib plus bevacizumab maintenance treatment of patients with advanced ovarian cancer (AOC) based on molecular status. Our aimed to compare the cost-effectiveness of olaparib plus bevacizumab for overall patients, patients with a breast cancer susceptibility genes (BRCA) mutation, homologous recombination deficiency (HRD), or HRD without BRCA mutations AOC from the context of the American healthcare system.

METHODS

Analysis of health outcomes in life-years (LYs), quality-adjusted life-years (QALYs), and the incremental cost-effectiveness ratio (ICER) in various molecular status-based AOC patient at a $150,000/QALY of willingness-to-pay was performed using a state-transitioned Markov model with a 20-year time horizon. Meanwhile, sensitivity analyses assessments were also used to gauge the model's stability.

RESULTS

The ICERs of olaparib plus bevacizumab versus bevacizumab alone were $487,428 ($374,758), $249,579 ($191,649), $258,859 ($198,739), and $270,736 ($206,640) per QALY (LY) in the overall patients, patients with BRCA mutations, patients with HRD, and patients with HRD without BRCA mutations AOC, respectively, which indicated that The ICERs was higher than $150,000/QALY in the US. Progression-free survival (PFS) value and olaparib cost emerged as the primary influencing factors of these findings in the sensitivity analysis.

CONCLUSION

At current cost levels, olaparib plus bevacizumab treatment is not a cost-effective treatment for patients with AOC regardless of their molecular status in the US. However, this maintenance treatment may be more favorable health advantages for patients with BRAC mutations AOC.

Liquid biopsy in ovarian cancer in China and the world: current status and future perspectives

Ovarian cancer (OC) is the eighth most common cancer in women, but the mild, non-specific clinical presentation in early stages often prevents diagnosis until progression to advanced-stage disease, contributing to the high mortality associated with OC. While serum cancer antigen 125 (CA-125) has been successfully used as a blood-borne marker and is routinely monitored in patients with OC, CA-125 testing has limitations in sensitivity and specificity and does not provide direct information on important molecular characteristics that can guide treatment decisions, such as homologous recombination repair deficiency. We comprehensively review the literature surrounding methods based on liquid biopsies, which may provide improvements in sensitivity, specificity, and provide valuable additional information to enable early diagnosis, monitoring of recurrence/progression/therapeutic response, and accurate prognostication for patients with OC, highlighting applications of this research in China.

Patient Assessment and Therapy Planning Based on Homologous Recombination Repair Deficiency

Defects in genes involved in the DNA damage response cause homologous recombination repair deficiency (HRD). HRD is found in a subgroup of cancer patients for several tumor types, and it has a clinical relevance to cancer prevention and therapies. Accumulating evidence has identified HRD as a biomarker for assessing the therapeutic response of tumor cells to poly(ADP-ribose) polymerase inhibitors and platinum-based chemotherapies. Nevertheless, the biology of HRD is complex, and its applications and the benefits of different HRD biomarker assays are controversial. This is primarily due to inconsistencies in HRD assessments and definitions (gene-level tests, genomic scars, mutational signatures, or a combination of these methods) and difficulties in assessing the contribution of each genomic event. Therefore, we aim to review the biological rationale and clinical evidence of HRD as a biomarker. This review provides a blueprint for the standardization and harmonization of HRD assessments.

Genetic characteristics of platinum-sensitive ovarian clear cell carcinoma

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

The cost-effectiveness analysis of maintenance olaparib plus Bevacizumab in patients with advanced ovarian cancer: based on the final survival results from PAOLA-1 trial

INTRODUCTION

In 2023, the final PAOLA-1 trial (NCT02477644) survival data were published documenting the benefits of therapy consisting of olaparib plus bevacizumab for patients with advanced ovarian cancer (AOC) as a function of molecular status. In light of these new data, the present study was conducted with the goal of evaluating the cost-effectiveness of olaparib plus bevacizumab for the treatment of the overall AOC patient population and for homologous recombination deficiency (HRD)-positive patients, patients with a breast cancer susceptibility gene (BRCA) mutations, homologous recombination proficiency (HRD)-positive, or patients not harboring BRCA mutations AOC from a US payers perspective.

METHODS

A Markov state-transition model with a 15-year time horizon was used to evaluate outcomes of patients administered Olaparib plus bevacizumab versus bevacizumab. Life-years (LYs), quality-adjusted LYs (QALYs), and the incremental cost-effectiveness ratio (ICER) values were evaluated in this study in light of a $150,000/QALY of willingness-to-pay (WTP) threshold. The stability of the established model was evaluated through sensitivity analyses.

RESULTS

Relative to bevacizumab alone, Olaparib plus bevacizumab was associated with mean incremental costs and QALYs (LYs) of olaparib plus bevacizumab versus bevacizumab were $293,656 and 1.85 (2.16), $265,668 and 3.34 (4.02), $242,746 and 1.71 (2.06), and $193,792 and 0.97 (1.14) for overall, BRCA mutation-positive, HRD-positive, and HRD-positive BRCA mutation-negative AOC patients, respectively. The corresponding ICER values for these patient subgroups were $158,729 ($136,218), $79,434 ($66,120), $141,636 ($117,747), and $200,595 ($169,733) per QALY (LY) gained Utility value and the price of olaparib were identified in sensitivity analyses as the primary factors influencing these results.

CONCLUSION

At current pricing levels, maintenance treatment with olaparib plus bevacizumab treatment may represent a cost-effective therapeutic option for BRCA mutations and HRD-positive AOC patients in the USA.

Prevalence of Homologous Recombination Deficiency in First-Line PARP Inhibitor Maintenance Clinical Trials and Further Implication of Personalized Treatment in Ovarian Cancer

Among ovarian cancer patients with BRCA mutation or homologous recombination deficiency (HRD), the efficacy of Poly-ADP-ribose polymerase (PARP) inhibitors such as olaparib, niraparib, veliparib, and rucaparib has been proven in a number of clinical trials. BRCA mutation and HRD are currently indicated for PARP inhibitor maintenance treatment in ovarian cancer. HRD diagnostic tests examine various components, resulting in different HRD status definitions and, as a result, different treatment decisions. A number of HRD diagnostic tests exist, but test results provided by different companies may differ as they use different methods and different cutoffs. HRD prevalence difference was shown between PARP inhibitor maintenance trials. It is important to select an appropriate method that can present accurate HRD phenotypes to predict sensitivity to PARP inhibitors so that patients who are most likely to benefit from treatment are selected. Additionally, in the subset data of the PARP inhibitor maintenance trials, there was a difference in HRD prevalence by race as higher HRD prevalence in Japanese and Chinese ovarian cancer patients was shown. Further large-scale investigations on racial differences in HRD prevalence are needed and this may contribute to changes in determining the treatment plan and personalized treatment in ovarian cancer patients.

Biomarker Assessment of Homologous Recombination Deficiency in Epithelial Ovarian Cancer: Association With Progression-Free Survival After Surgery

Identifying BRCA mutations and homologous recombination deficiency (HRD) is the key to choosing patients for poly (ADP-ribose) polymerase inhibitor (PARPi) therapy. At present, a large amount of research focuses on the application of HRD detection in ovarian cancer. However, few studies have discussed the relationship between HRD detection and postoperative survival in patients with epithelial ovarian cancer (EOC). This study included 38 consecutive patients with EOC who underwent cytoreduction surgery. Owing to tissue availability, only 29 patients underwent molecular profiling and survival analysis. Overall, 21 (72.4%) tumors had HRD scores of ≥42. Mutations in BRCA were observed in 5/29 (17.2%) patients. In this cohort, an HRD score of ≥42 was more common in serous ovarian tumors. We found no statistically significant association between homologous recombination repair (HRR) genes and HRD scores except for tumor protein P53 (TP53) mutation. We also found a strong positive association between HRD scores and chromosomal instability (CIN). In the survival analysis, an HRD score of >23 was correlated with better postoperative progression-free survival (pPFS). With increased depth of research, an appropriate HRD score threshold may serve as a prognostic tool and should be assessed in future studies to predict the clinical value of PARPi.