Health-Related Quality of Life in PARP-Inhibitor Olaparib Maintenance in Ovarian Cancer Patients: Real World Data and Experience of a Single-Center in China

Objectives: To preliminarily explore the germline BRCA1/2 gene mutation status of patients with epithelial ovarian cancer (EOC), analyze the relationship with clinicopathological characteristics and the impact on survival and prognosis. Then examine the BRCA1/2 gene sequence mutation rate and the QOL of ovarian cancer patients with oral Olaparib in a single-center of China. Methods: A retrospective analysis of the survival and prognostic factors of 82 ovarian cancer patients who had undergone genetic testing in the Department of Gynecology, the First Aliated Hospital of Nanjing Medical University from 2015 to 2018. These patients also underwent germline BRCA1/2 genetic testing. Then, we use the Quality of Life Questionnaire (QLQ-C30) and the Quality of Life Ovarian Cancer 28 Questionnaire (QLQ-OV28) to determine the relationship between quality of life (QOL) in each category, and key demographic and clinical factors.


Introduction
Epithelial ovarian cancer (EOC) is the gynecological malignant tumor with the highest fatality rate. At the time of treatment, patients are often at an advanced stage. Despite satisfactory primary debulking surgery (PDS) combined with platinum-based chemotherapy, 70% of patients still relapse within two years [1][2]. In recent years, the latest biological knowledge has shown that almost half of advanced ovarian cancers exhibit changes in homologous recombination (HR), which is a high-delity doublestrand break (DSB) DNA repair mechanism that starts during cell replication [3][4]. These alterations can lead to HR De ciency (HRD), resulting in lack of DNA integrity, and a better response to DNA damaging agents, such as platinum compounds [5]. Among these alterations, BRCA1 and BRCA2 mutations account for 22.6% of HGSOC mutations. Patients with these mutations are highly responsive to platinum, and have been treated with PolyADP Ribose Polymerase inhibitors (PARPis) to discover this biological characteristic. The inhibitors causes HRD cell apoptosis based on a synthetic lethal mechanism [6][7][8][9]. In vitro, studies have shown that BRCA1/2 mutated cell lines are sensitive to PARPis. Clinical trials have con rmed that although interesting activities are also observed in BRCA wild-type ovarian cancers, patients with BRCA1/2 mutations show the greatest bene t of PARPis [8][9][10].
Olaparib (Lynparza™) is a PARP inhibitor that can induce synthetic lethality in BRCA1/2-de cient tumor cells [11][12]. According to previous research results, Olaparib is the effectiveness treatment for platinumsensitive high-grade serous recurrent ovarian cancer (HSROC). Study 19 (NCT00753545) is a Phase II trial to assess the e cacy and safety of Olaparib maintenance monotherapy in platinum-sensitive HSROC patients, the data from which showed a signi cant improvement in PFS in the Olaparib-treated group relative to the placebo group (hazard ratio (HR) 0.35, 95% con dence interval (CI) 0.25-0.49; p < 0.0001) [13]. SOLO2 (Study of Olaparib in Ovarian cancer) is the Phase III trial (NCT01874353), which aimed to concluded the PFS in the Olaparib-treated group compared to the placebo group (HR 0.30, 95% CI 0.22-0.41; p < 0.0001) among the patients with platinum-sensitive HSROC and a BRCA1/2 mutation (BRCAm) as maintenance monotherapy [14].
Olaparib is an oral inhibitor of PARP 1, PARP 2, and PARP 3 [15][16]. It was approved by EMA in 2014 for platinum-sensitive relapsed ovarian cancer patients with BRCA mutations (germ cells and/or somatic cells). This approval was based on results from Study 19, a randomized, placebo controlled phase II trial [10,13,[17][18]] that was con rmed by SOLO2 trial, an international, multicentre, phase III randomized, double blind, placebo controlled trial [14]. In this latter trial patients receiving Olaparib maintenance therapy achieved an improvement of 13.6 months in PFS (19.1 vs 5.5 months in placebo arms, HR 0.30 p < 0·0001) [19].
Although there are many real-world research results on the adverse reactions of PARPi, the quality of life of patients after oral administration of PARPi is rarely reported. This study conducted EORCT-Q30 and QLQ-OV28 questionnaire surveys on 42 patients who took PARPi drugs orally, hoping to analyze the safety and effectiveness of the drugs. Although there are many real-world research results on the adverse reactions of PARPi, there are few reports on the quality of life of patients after oral administration of PARPi. This study conducted EORCT-Q30 and QLQ-OV28 questionnaire surveys on 42 patients taking PARPi drugs, hoping to analyze the safety and effectiveness of the drugs.

Patients
This study is a retrospective analysis of patients with epithelial ovarian cancer who were treated in the Gynecology Department, the First A liated Hospital of Nanjing Medical University from January 2015 to January 2020 and met the following conditions: 1) After surgery or biopsy in our hospital patients with epithelial ovarian cancer diagnosed by histopathology; 2) Gene detection results of high-throughput second-generation sequencing technology have been available. All patients signed an informed consent form. A total of 82 ovarian cancer patients underwent cytoreductive surgery and chemotherapy at the Gynecology Department of The First A liated Hospital of Nanjing Medical University from June, 2015 to December, 2018. We enrolled demographic and clinical information of the participants by reviewing medical records and interviewing patients, such as age, marital status, education, menstrual history.

QOL evaluation
We employed two common questionnaires to estimate the QOL of study participants. They were Quality of Life Questionnaire (QLQ-C30) and the simpli ed Chinese version of the Quality of Life Ovarian Cancer 28 Questionnaire (QLQ-OV28) questionnaire, the rst of which was the simpli ed Chinese version (3.0) of the European Organization for Research and Treatment [EORCT] 30-Item Core, and the second of which was speci c to ovarian cancer. Previous studies have shown that both types of questionnaires have good reliability, validity, feasibility and responsiveness [20]. We strictly follow the steps prescribed by the EORTC QOL group to score and calibrate the questionnaire. QLQ-C30 has a higher function and overall health score, and QLQ-OV28 has a higher sexual function score, indicating that the higher the QOL score, the more severe the individual's symptoms [21][22].

Statistical analysis
Baseline characteristics were analyzed according to descriptive statistics. Continuous variables were described with median values and interquartile range; categorical variables were described in terms of absolute numbers and proportion over the total number of patients analyzed.

Health-related quality of life
We used the QLQ-C30 (version 3.0) to assess Health-related quality of life (HRQoL) [23]. This questionnaire not only contains ve functional scales regarding physical, role, cognitive, emotional and social functioning and a global health status scale, but also comprises symptom scales on fatigue, nausea and vomiting, pain, dyspnea, insomnia, appetite loss, constipation, diarrhea and nancial problems. Each item is scored on a 4-point scale ranging from 1: not at all, to 4: very much. All scale scores were linearly transformed to a 0-100 score [24]. The higher the score on the functional scale and overall health status/QOL, represent the better HRQoL, while the higher the score on the symptom scale, the worse the HRQoL.

Results
Analysis of patient's germline BRCA gene mutation A total of 82 patients with epithelial ovarian cancer were enrolled, and 25 cases of BRCA1/2 pathogenic mutations were found, with a total mutation rate of 30.48%. Among them, 17 cases of BRCA1 pathogenic mutation, the mutation rate was 20.73%. There were 8 cases of BRCA2 pathogenic mutation, the mutation rate was 9.75%. A total of 13 pathogenic mutations in BRCA1 were detected, including c.2160delA, c.3770_3771delAG, c.5470_5477delATTGGGCA, c.3255_3259del (p.Leu1086fs), c.3294del (p.Pro1099fs), c.4782del (p.Ser1595fs), c.587dupA (p.Tyr196fs), c.4065_4068delTCAA, c.4132delG these 9 sites are frame-shift mutations, followed by c.3967C>G, c.1115G>A, c.4801A>T, C.6528C >G is a missense mutation. A total of 7 pathogenic mutations were detected in BRCA2, c.1495C>T, c.6528C>G, c.2041G>A, c.4593dupA were missense mutations, c.1499del (p.Gly500fs), c.3770_3771dell (p.Glu1257fs), c.6405_6409delCTTAA were frame-shift mutations. The clinical signi cance of c.4132delG locus and C.6528C>G locus is unknown and there is no literature report, which may have potential research value (Table 1). onset and menstrual status between the two groups of patients (P>0.05), and they were comparable. The pathogenic mutation status of BRCA1/2 gene is related to pathological type, platinum sensitivity, neoadjuvant chemotherapy, and the difference between groups is statistically signi cant (P<0.05) ( Table   2). Among the patients undergoing germline BRCA mutation gene detection, a total of 42 patients were treated with Olaparib orally, and 40 patients were selected as the control group.

Olaparib status and QOL
All 82 patients completed the QLQ C30 and QLQ OV28 questionnaires at the time of initial enrollment. Table 3 shows the QOL scores of patients with different Olaparib strata. At the early stage of the enrollment survey, the overall health score of QLQ-C30 was very low. The lowest scores are social function and cognitive function. In terms of symptoms, nancial di culties are the most serious. The QLQ-OV28 sexual score was the lowest. Among these 44/82 patients, 35/71 (86.5%) reported complete loss of interest in sex, and the remaining 7/11 (13.4%) reported low interest in sex. A total of 38/75 patients (91.4%) reported no sexual activity at all. Only 6/11 patients reported that they had sexually activity, but all said that they rarely experienced sexual enjoyment. We used linear regression models to establish the correlation between Olaparib status and QOL at the time of initial enrollment (Table 3).
Patients suffered more severe symptoms of constipation (P = 0.001), poor body image (P = 0.003), poor attitude toward treatment and disease (P < 0.0001), and other chemotherapy side effects (P = 0.020). They suffered from more severe constipation symptoms (P = 0.001), poor body image (P = 0.003), poor attitudes towards treatment and disease (P < 0.0001), and other side effects of chemotherapy (P = 0.020).
There were 82 patients that completed both the baseline and follow-up surveys and changes in QOL outcomes were determined for this group. 42 patients completed the baseline and follow-up surveys, and determined the changed outcomes in QOL results for this group.
Our research results show that the physical, role function and cognitive function as well as the range of nausea and vomiting, insomnia, loss of appetite and other side-effects were signi cantly worsened (Table  3). Then, we identi ed patients with deteriorating QOL who had lower scores in terms of functional domain, global health, and sexual function; or increased other symptom domains during follow-up (Table  3).
We applied a logistic regression model to determine whether Olaparib status can predict the risk of QOL deterioration. Our results show that patients without Olaparib had a signi cantly higher risk of deterioration in their quality of life in terms of physical function (P = 0.001), role function (P = 0.0140), emotional function(P = 0.021), pain (P = 0.010) , and nancial di culties (P = 0.003) ( Table 3).

Discussion
In recent years, many studies have revealed the important role of BRCA1/2 in the mechanism of DNA damage repair. BRCA1/2 mutation induces synthetic lethality in cells with potential HRD (homologous recombination defect). Single nucleotide polymorphisms and mutations of BRCA gene are the main causes of abnormal structure and function of BRCA gene [25]. At present, patients with ovarian cancer with BRCA1/2 mutations, especially those with advanced recurrence of ovarian cancer, often take personalized treatment measures [26]. In addition to surgery and chemotherapy, oral PARPi drugs are more likely to be used as rst-line maintenance therapy or chemotherapy to achieve CR/PR maintenance after recurrence. Although the status of BRCA1/2 mutation is important for clinical decision-making and prognosis of ovarian cancer, China is still in the exploratory stage, and more multi-center clinical studies are needed to enter clinical practice.
This study describes the BRCA mutation status of 82 patients with epithelial ovarian cancer undergoing genetic testing, the relationship with common clinicopathological factors, and the positive impact on the prognosis. In our study, the total mutation rate was 30.48%, among which the BRCA1 mutation rate was 20.73%, and the BRCA2 mutation rate was 9.75%. In collaboration with Shan-Mughapriya's studies on ovarian cancer patients from different regions and races were conducted and the results of the systematic analysis were basically consistent (the gene mutation rates of BRCA1 and BRCA2 are 1.1%~39.7% and 0~13.9%, respectively) [25]. BRCA1/2 gene mutation types include frameshift mutations, nonsense mutations, missense mutations, synonymous mutations and splicing mutations. Among them, there are three types of frameshift mutations, nonsense mutations and splicing mutations, and their common feature is the early termination of protein coding synthesis [26]. In this study, BRCA1 detected a total of 9 frameshift mutations and 4 missense mutations, and BRCA2 detected a total of 3 frameshift mutations and 4 missense mutations. Frameshift mutations can cause BRCA to appear stop codons in advance, form a truncated protein or change the primary structure of the protein, thereby causing BRCA protein dysfunction. Missense mutations can cause changes in amino acid coding. According to current data, these mutations can affect the function of BRCA protein and lead to the development of ovarian cancer. However, the clinical signi cance of c.4132delG locus and C.6528C>G locus is unknown, and there is no literature report. It needs to be studied in future work.
There are several articles reporting the effectiveness and safety of Olaparib in patients with HSROC [15][16]19], but there are no research reports on QOL in patients with Olaparib. To the best of our knowledge, this study represents the rst investigation of the QOL of ovarian cancer patients who taken Olaparib. Our study included 42 Olaparib patients and 40 ovarian cancer patients without Olaparib.
We currently know that Olaparib and other PARPis maintenance treatment can signi cantly improved the overall PFS of platinum-sensitive relapsed ovarian cancer patients according to registrative clinical trials. Study 19 is a randomized, double-blind, placebo-controlled, multi-center Phase II clinical study designed to evaluate the e cacy and safety of Olaparib versus placebo in patients with recurrent high-grade serous ovarian cancer. The results indicated that patients receiving Olaparib 400mg twice a day as maintenance therapy had a longer PFS (8.4 vs 4.8 months in placebo arm with HR of 0.35 P < 0.001) with a greater bene t in BRCA (germline and somatic) mutated subgroup (11.2 vs 4.3 months HR 0.18 P < 0.0001) [10,13,17,18].
The results of the SOLO-2 phase III clinical study showed that patients with BRCA-mutated platinumsensitive relapsed ovarian cancer who received Olaparib tablets (300mg twice a day) had signi cantly prolonged PFS compared with placebo. The study reached the main study endpoint: the investigator assessed PFS (median PFS 19.1 months vs 5.5 months) and had low toxicity and high safety [14,19].
After these results Olaparib has been rapidly introduced in everyday practice, modifying treatment algorithms. Nevertheless, in SOLO2 and Study 19 trial, as usually in all registrative trials [13], Olaparib was administered to very selected patients from highly experienced providers with very straight rules, time lines and schedules per protocol. This improved PFS obtained in an ideal setting needs external validity in a less selected population. The results of the highly anticipated 5-year follow-up of the SOLO1 study were announced on ESMO 2020. The results showed that mPFS in the Olaparib group lasted up to 56 months, reduced the risk of disease progression or death by 67%, and 48% of patients had no disease progression in 5 years. These patients may have achieved clinical "cure".
And we still need real world studies to de ne if drugs are effective in real world setting. Few results from Olaparib real world use have been reported, with short follow up [27][28] or small population [29], lacking essential clinical information like BRCA status [30] and focusing above all on safety. This is the rst QOL study on patients with ovarian cancer undergoing maintenance treatment with oral olaparib in China. Our real-world experience of the QOL of Olaparib maintenance treatment in HSROC patients with BRCA1/2 mutation is consistent with that reported in previous studies [15][16]19] with tolerable toxicity pro les. Our results can be compared to those of Study 19, a phase II trial of Olaparib capsules as maintenance monotherapy in patients with platinum-sensitive HSROC, as we used the same indications and regimen (capsule 400 mg bid). The use of Olaparib in China was permitted based on the results of NCCN guideline and it is mandatory for physicians in China to follow the recommendations and guidelines of NCCN.
Limitations: rst of all, because this study is based on ovarian cancer patients undergoing oral maintenance treatment with Olaparib in our center, the detection time is close to the follow-up end point, and there is obvious survivor bias. Therefore, the overall survival time OS data analyzed in this study is short. In subsequent studies, we can increase the overall survival rate statistics in the process of expanding the sample size. Secondly, the sample size of this study is small, and it is only a preliminary exploratory study. The conclusions obtained and their speci c related mechanisms need to be further con rmed. Declarations Ethics approval and consent to participate All patients signed informed consent before using clinical specimens. The use of specimens for this study has been proved by the ethics committee of the First A liated Hospital with Nanjing Medical University.

Consent for publication
Not applicable Availability of data and materials They could be achieved upon reasonable request to the authors.