The First Nationwide Multicenter Prevalence Study of Germline BRCA1 and BRCA2 Mutations in Chinese Ovarian Cancer Patients

Is the Homologous Recombination Repair Mutation Defined by a 15-Gene Panel Associated with the Prognosis of Epithelial Ovarian Cancer?

BACKGROUND

There is no consensus regarding the specific genes included in the homologous recombination repair (HRR) gene panel for identifying the HRR deficiency (HRD) status and predicting the prognosis of epithelial ovarian cancer (EOC) patients.

OBJECTIVE

We aimed to explore a 15-gene panel involving the HRR pathway as a predictive prognostic indicator in Chinese patients newly diagnosed with EOC.

PATIENTS AND METHODS

We reviewed the previously published reports about different HRR gene panels and prespecified the 15-gene panel. The genetic testing results in a 15-gene panel from 308 EOC patients diagnosed between 2014 and 2022 from six centers were collected. The association of clinicopathologic characteristics, the use of poly (adenosine diphosphate-ribose) polymerase inhibitors (PARPis) and progression-free survival (PFS) with 15-gene panel HRR mutations (HRRm) status was assessed.

RESULTS

43.2% (133/308) of patients were determined to carry 144 deleterious HRRm, among which 68.1% (98/144) were germline mutations and 32.8% (101/308) were BRCA1/2 gene lethal mutations. The hazard ratio (HR) (95% confidence interval, CI) for PFS (HRRm v HRR wild type, HRRwt) using the 15-gene panel HRRm was 0.42 (0.28-0.64) at all stages and 0.42 (0.27-0.65) at stages IIIC-IV. However, a prognostic difference was observed only between the BRCA mutation group and the HRRwt group, not between the non-BRCA HRRm group and the HRRwt group. For the subgroups of patients not using PARPis, the HR (95% CI) was 0.41 (0.24-0.68) at stages IIIC-IV.

CONCLUSIONS

This study provides evidence that 15-gene panel HRRm can predict the prognosis of EOC, of these only the BRCA1/2 mutations, not non-BRCA HRRm, contribute to prognosis prediction. Among patients without PARPis, the HRRm group presented a better PFS. This is the first study of this kind in the Chinese population.

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.

Germline Mutational Landscape and Novel Targetable RAD51D Variant in Chinese Patients With Ovarian Cancer

PURPOSE

Genetic variants of ovarian cancer (OV) show ethnic differences, but data from the Chinese population are still insufficient. Here, we elucidate the inheritance landscape in Chinese patients with OV and examine the functional implications of a Chinese-enriched RAD51D variant.

METHODS

Between 2015 and 2018, 373 consecutive patients with OV were prospectively enrolled. Variants of BRCA1/2, other homologous recombination repair (HRR) genes, and DNA mismatch repair (MMR) genes were analyzed using next-generation sequencing. An enriched RAD51D variant was identified, and its functional effects were examined using Cell Counting Kit-8, colony formation, transwell migration, and drug sensitivity assays.

RESULTS

Overall, 31.1% (116/373) of patients had at least one pathogenic or likely pathogenic germline variant. BRCA1 and BRCA2 accounted for 16.09% and 5.36%, respectively, with one patient having both variants. In addition, 32 (8.58%) patients carried other HRR gene variants, whereas three (0.8%) patients had MMR gene variants. The RAD51D variant ranked third (8/373, 2.1%), and its rate was much higher than that in other populations. Remarkably, all eight patients harbored the RAD51D K91fs variant (c.270_271dup, p.Lys91Ilefs*13) and demonstrated satisfactory platinum response and favorable prognosis. This variant confers enhanced sensitivity to poly (ADP-ribose) polymerase inhibitors in OV cells. However, the effects on platinum sensitivity were inconsistent across different cell lines. Against the background of the TP53 variant, RAD51D K91fs variant showed increased sensitivity to cisplatin.

CONCLUSION

Our study revealed the inheritance landscape of OV and identified an enriched RAD51D variant in Chinese patients with OV. This can serve as an important reference for OV management and a potential therapeutic target.

Mutation characteristics of cancer susceptibility genes in Chinese ovarian cancer patients

Introduction

The association between mutations in susceptibility genes and the occurrence of ovarian cancer has been extensively studied. Previous research has primarily concentrated on genes involved in the homologous recombination repair pathway, particularly BRCA1 and BRCA2. However, a wider range of genes related to the DNA damage response pathways has not been fully explored.

Methods

To investigate the mutation characteristics of cancer susceptibility genes in the Chinese ovarian cancer population and the associations between gene mutations and clinical data, this study initially gathered a total of 1171 Chinese ovarian cancer samples and compiled a dataset of germline mutations in 171 genes.

Results

In this study, it was determined that MC1R and PRKDC were high-frequency ovarian cancer susceptibility genes in the Chinese population, exhibiting notable distinctions from those in European and American populations; moreover high-frequency mutation genes, such as MC1R: c.359T>C and PRKDC: c.10681T>A, typically had high-frequency mutation sites. Furthermore, we identified c.8187G>T as a characteristic mutation of BRCA2 in the Chinese population, and the CHEK2 mutation was significantly associated with the early onset of ovarian cancer, while the CDH1 and FAM175A mutations were more prevalent in Northeast China. Additionally, Fanconi anemia pathway-related genes were significantly associated with ovarian carcinogenesis.

Conclusion

In summary, this research provided fundamental data support for the optimization of ovarian cancer gene screening policies and the determination of treatment, and contributed to the precise intervention and management of patients.

Prognostic factors and the role of primary debulking in operable stage IVB ovarian cancer with supraclavicular lymph node metastasis: a retrospective study in Chinese patients

BACKGROUND

Recent studies showed heterogeneity in stage IVB patients. However, few studies focused on the prognosis of supraclavicular metastatic ovarian cancer. This study aimed to explore the prognostic factors and the role of primary debulking in IVB ovarian cancer patients with supraclavicular lymph node metastasis.

METHODS

We retrospectively analyzed patients newly diagnosed as primary epithelial ovarian cancer with supraclavicular lymph node metastasis from January 2015 to July 2020. Supraclavicular lymph node metastasis was defined as either the pathological diagnosis by supraclavicular lymph node biopsy, or the radiological diagnosis by positron emission tomography-computed tomography (PET-CT).

RESULTS

In 51 patients, 37 was diagnosed with metastatic supraclavicular lymph nodes by histology, 46 by PET-CT, and 32 by both methods. Forty-four (86.3%) with simultaneous metastatic paraaortic lymph nodes (PALNs) by imaging before surgery or neoadjuvant chemotherapy were defined as "continuous-metastasis type", while the other 7 (13.7%) defined as "skip-metastasis type". Nineteen patients were confirmed with metastatic PALNs by histology. Thirty-four patients were investigated for BRCA mutation, 17 had germline or somatic BRCA1/2 mutations (g/sBRCAm). With a median follow-up of 30.0 months (6.3-63.4 m), 16 patients (31.4%) died. The median PFS and OS of the cohort were 17.3 and 48.9 months. Survival analysis showed that "continuous-metastasis type" had longer OS and PFS than "skip-metastasis type" (OS: 50.0/26.6 months, PFS: 18.5/7.2months, p=0.005/0.002). BRCA mutation carriers also had longer OS and PFS than noncarriers (OS: 57.4 /38.5 m, p=0.031; PFS: 23.6/15.2m, p=0.005). Multivariate analysis revealed only metastatic PALNs was independent prognostic factor for OS (p=0.040). Among "continuous-metastasis type" patients, 22 (50.0%) achieved R0 abdominopelvic debulking, who had significantly longer OS (55.3/42.3 months, p =0.034) than those with residual abdominopelvic tumors.

CONCLUSIONS

In stage IVB ovarian cancer patients with supraclavicular lymph nodes metastasis, those defined as "continuous-metastasis type" with positive PALNs had better prognosis. For them, optimal abdominopelvic debulking had prognostic benefit, although metastatic supraclavicular lymph nodes were not resected. Higher BRCA mutation rate than the general population of ovarian cancer patients was observed in patients with IVB supraclavicular lymph node metastasis, leading to better survival as expected.

Population-based BRCA germline mutation screening in the Han Chinese identifies individuals at risk of BRCA mutation-related cancer: experience from a clinical diagnostic center from greater Shanghai area

BACKGROUND

Deleterious BRCA1/2 (BRCA) mutation raises the risk for BRCA mutation-related malignancies, including breast, ovarian, prostate, and pancreatic cancer. Germline variation of BRCA exhibits substantial ethnical diversity. However, there is limited research on the Chinese Han population, constraining the development of strategies for BRCA mutation screening in this large ethnic group.

METHODS

We profile the BRCA mutational spectrum, including single nucleotide variation, insertion/deletion, and large genomic rearrangements in 2,080 apparently healthy Chinese Han individuals and 522 patients with BRCA mutation-related cancer, to determine the BRCA genetic background of the Chinese Han population, especially of the East Han. Incident cancer events were monitored in 1,005 participants from the healthy group, comprising 11 BRCA pathogenic/likely pathogenic (PLP) variant carriers and 994 PLP-free individuals, including 3 LGR carriers.

RESULTS

Healthy Chinese Han individuals demonstrated a distinct BRCA mutational spectrum compared to cancer patients, with a 0.53% (1 in 189) prevalence of pathogenic/likely pathogenic (PLP) variant, alongside a 3 in 2,080 occurrence of LGR. BRCA1 c. 5470_5477del demonstrated high prevalence (0.44%) in the North Han Chinese and penetrance for breast cancer. None of the 3 LGR carriers developed cancer during the follow-up. We calculated a relative risk of 135.55 (95% CI 25.07 to 732.88) for the development of BRCA mutation-related cancers in the BRCA PLP variant carriers (mean age 42.91 years, median follow-up 10 months) compared to PLP-free individuals (mean age 48.47 years, median follow-up 16 months).

CONCLUSION

The unique BRCA mutational profile in the Chinese Han highlights the potential for standardized population-based BRCA variant screening to enhance BRCA mutation-related cancer prevention and treatment.

Characteristics of germline DNA damage response gene mutations in ovarian cancer in Southwest China

DNA damage response (DDR) pathways are responsible for repairing endogenous or exogenous DNA damage to maintain the stability of the cellular genome, including homologous recombination repair (HRR) pathway, mismatch repair (MMR) pathway, etc. In ovarian cancer, current studies are focused on HRR genes, especially BRCA1/2, and the results show regional and population differences. To characterize germline mutations in DDR genes in ovarian cancer in Southwest China, 432 unselected ovarian cancer patients underwent multi-gene panel testing from October 2016 to October 2020. Overall, deleterious germline mutations in DDR genes were detected in 346 patients (80.1%), and in BRCA1/2 were detected in 126 patients (29.2%). The prevalence of deleterious germline mutations in BRCA2 is higher than in other studies (patients are mainly from Eastern China), and so is the mismatch repair genes. We identified three novel BRCA1/2 mutations, two of which probably deleterious (BRCA1 p.K1622* and BRCA2 p.L2987P). Furthermore, we pointed out that deleterious mutations of FNACD2 and RECQL4 are potential ovarian cancer susceptibility genes and may predispose carriers to ovarian cancer. In conclusion, our study highlights the necessity of comprehensive germline mutation detection of DNA damage response genes in ovarian cancer patients, which is conducive to patient management and genetic counseling.

CD47-a novel prognostic predicator in epithelial ovarian cancer and correlations with clinicopathological and gene mutation features

BACKGROUND

Epithelial ovarian cancer (EOC) is insensitive to immunotherapy due to its poor immunogenicity; thus, suitable biomarkers need to be identified for better prognostic stratification and individualized treatment. CD47 is a novel immunotherapy target; however, its impact on EOC prognosis is controversial and correlation with genetic features is unclear. The aim of this study was to investigate the prognostic significance of CD47 and its correlations with biological behaviors and genetic features of EOC.

METHODS

Immunohistochemistry (IHC) and next-generation sequencing (NGS) were performed to examine expressions of CD47, PD-L1, and genomic mutations in the tissue samples of 75 EOC patients. Various clinicopathologic and genomic features were then evaluated to determine their correlation with CD47 expression. Kaplan-Meier analysis and Cox regression analysis were used to identify independent prognostic factors. Risk score modeling was then established, and the predictive capacity of this model was further confirmed by nomogram analysis.

RESULTS

CD47 was mainly expressed in the tumor cell membrane and cytoplasm, and the rate of high CD47 expression was 63.7%. CD47 expression was associated with various clinicopathological factors, including FIGO stage, CA125 and HE4 value, presence of multidisciplinary surgeries, presence and volume of ascites, lymph-node metastasis, Ki-67 index and platinum-resistant, as well as genetic characteristics like BRCA mutation, HRD status, and TP53 mutation in EOC. Patients with high CD47 expression showed worse prognosis than the low-expression group. Cox regression analysis demonstrated that CA125, CD47, and BRCA mutation were independent factors for EOC prognosis. Patients were then categorized into high-risk and low-risk subgroups based on the risk score of the aforementioned independent factors, and the prognosis of the high-risk group was worse than those of the low-risk group. The nomogram showed adequate discrimination with a concordance index of 0.777 (95% CI, 0.732-0.822). The calibration curve showed good consistency.

CONCLUSION

CD47 correlated with various malignant biology and genetic characteristics of EOC and may play pivotal and multifaceted roles in the tumor microenvironment of EOC Finally, we constructed a reliable prediction model centered on CD47 and integrated CA125 and BRCA to better guide high-risk population management.

A MALDI-TOF mass spectrometry-based method for detection of copy number variations in BRCA1 and BRCA2 genes

Background: Identifying germline mutations in BRCA1 and BRCA2 genes (BRCAs) would benefit the carriers in multiple aspects. In addition to single-nucleotide variations and small indels, copy number variations (CNVs) is also an indispensable component of identifiable mutations in BRCAs. A sensitive, rapid and throughput-flexible method to detect CNVs would be preferred to meet the rising clinical requirements for BRCAs testing. Methods: We developed a MALDI-TOF-MS-based method (MS assay) which included three steps: first, multiplex end-point PCR followed by a single base extension reaction; second, automated analyte transfer and data acquisition; third, data analysis. We applied MS assay to detect CNVs in BRCAs in 293 Chinese patients with ovarian or pancreatic cancer. All the samples were examined by targeted next-generation sequencing (TS) simultaneously. Samples were further cross-validated by multiplex ligation-dependent probe amplification (MLPA) if the results from MS assay and TS were inconsistent. Long range PCR was then applied to identify the exact breakpoints in BRCAs. Results: MS assay introduced highly multiplexed panels to detect CNVs of BRCAs semi-quantitatively. Simplified on-board data analysis was available for MS assay and no complex bioinformatics was needed. The turnaround time of MS assay was less than 8 hours with a hands-on time of only 40 min. Compared to TS, MS assay exhibited higher sensitivity (100% vs. 75%) and was more flexible in throughput, with the reagent cost per sample remaining constant no matter how many samples were examined per assay. A total of eight CNVs in BRCAs were detected from the 293 samples, and the molecular breakpoints were successfully identified in five samples through long-range PCR followed by Sanger sequencing. Conclusion: Our results suggested that MS assay might be an effective method in primary screening for CNVs in genes such as BRCAs, especially when short turnaround time and/or high sensitivity is a top priority.

Efficacy of poly (ADP-ribose) polymerase inhibitors monotherapy and the impact to subsequent platinum-based chemotherapy in breast cancer susceptibility genes1/2-mutated ovarian cancer patients with secondary platinum-sensitive relapse

BACKGROUND

The therapeutic effect of poly (ADP-ribose) polymerase inhibitors (PARPi) monotherapy compared with platinum-based chemotherapy, and the impact to subsequent platinum-based chemotherapy after PARPi resistance were inconclusive in breast cancer susceptibility genes (BRCA)1/2-mutated ovarian cancer patients with secondary platinum-sensitive relapse.

METHODS

BRCA1/2-mutated patients with secondary platinum-sensitive relapse included in this study did not receive any maintenance regimen after first- and second-line platinum-based chemotherapy, and the secondary platinum-free interval (PFI) was more than 6 months. Patients in study group were treated with PARPi monotherapy until disease progression, and patients in control group were treated with platinum-based chemotherapy without restriction. Progression-free survival (PFS) was defined as the time from third-line therapy to disease progression or death, PFS2 was defined as the time from platinum-based chemotherapy after PARPi resistance to next subsequent therapy or death. Post-recurrence survival (PRS) refers to the survival time after secondary platinum-sensitive relapse.

RESULTS

A total of 119 patients were retrospectively analyzed, including 71 (59.7%) in study group and 48 (40.3%) in control group. The objective response rate (ORR: 77.5% vs. 80.0%, p=0.766) and PFS (median: 11.2 vs. 11.0 months, p=0.962) were comparable. The benefit of subsequent platinum-based chemotherapy after PARPi resistance was more pronounced in patients with PARPi treatment for more than 12 months (median PFS2: 8.6 vs. 4.3 months, p=0.040). PARPi monotherapy had no adverse effect on PRS compared with platinum-based chemotherapy (median PRS:41.2 vs. 42.8 months, p=0.323). Compared to patients in control group who had never received PARPi, PARPi monotherapy (median PRS: 41.2 vs. 33.7 months, p=0.019) and post-line treatment with PARPi in the control group (median PRS: 48.1 vs. 33.7 months, p=0.002) could prolong PRS for patients with secondary platinum-sensitive relapse.

CONCLUSIONS

PARPi monotherapy was similar to platinum-based chemotherapy for BRCA1/2-mutated ovarian cancer patients with secondary platinum-sensitive recurrence, and could improve prognosis.

Germline Pathogenic Variants and Genetic Counseling by Ancestry in Patients With Epithelial Ovarian Cancer

PURPOSE

To evaluate rates of germline pathogenic/likely pathogenic variants (PVs) and genetic counseling by ancestry in patients with epithelial ovarian cancer (EOC).

METHODS

Patients with pathologically confirmed EOC who underwent clinical tumor-normal sequencing from January 1, 2015, to December 31, 2020, inclusive of germline analysis of ≥76 genes were included. Patients with newly identified PVs were referred for Clinical Genetics Service (CGS) counseling. Ancestry groups were defined using self-reported race/ethnicity and Ashkenazi Jewish (AJ) heritage. Genetic ancestry was inferred computationally using validated algorithms. Logistic regression models were built.

RESULTS

Of 1,266 patients, self-reported ancestry (AJ, 17%; Asian, 10%; Black/African American, 5.4%; Hispanic, 6.2%; non-Hispanic White, 57%; other, 0.16%; unknown, 4.0%) correlated with genetic ancestry (AJ ancestry, 18%; admixed, 10%; African, 4%; East Asian [EAS], 6%; European, 56%; Native American, 0.2%; South Asian [SAS], 4%; unknown, 2%). Germline PVs were observed in 313 (25%) patients, including 195 (15%) with PVs in EOC-associated genes. Those with PVs were younger at diagnosis (59 v 62 years; P < .001) and more likely to have high-grade serous ovarian cancer (83% v 72%; P = .009). PV prevalence varied between ancestry groups (P < .001), with highest rates in the AJ (39.9%) and Asian (26.5%) groups and similar rates (>10%) across other ancestry groups. Use of genetic ancestry demonstrated similar findings and further characterized high rates of PV in EAS/SAS groups. Younger age, high-grade serous histology, and self-reported AJ or Asian ancestry were associated with PV in an EOC-associated gene. Rates of CGS counseling for newly identified PVs were high (80%) across ancestry groups.

CONCLUSION

Rates of PV, particularly in EOC-associated genes, were high regardless of ancestry, with similar rates of counseling between groups, emphasizing the importance of universal genetic testing in all patients with EOC.

Factors predicting BRCA1/2 pathogenic variants in patients with ovarian cancer: a systematic review with meta-analysis

AIM

To provide accurate figures of the frequency of specific clinical features in ovarian cancer (OC) associated with germline BRCA1/2 pathogenic variants and to define their relevance in predicting the presence of a germline pathogenic variant in these genes.

METHODS

A systematic review of papers published from 1995 to February 2022 was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Data from eligible papers were synthesised through meta-analysis.

RESULTS

Thirty-seven papers were reviewed, including a total of 12 886 patients with OC. Among BRCA carriers, 86.4% displayed serous type, 83.3% high grade (G3), 83.7% FIGO (The International Federation of Gynecology and Obstetrics) stage III/IV, 39.7% age at diagnosis ≤50 years and 18.1% personal breast cancer history, while the frequency of these features in non-carriers resulted significantly lower (p<0.001). The meta-analysis showed that the strongest predictor of BRCA1/2 pathogenic variants was a personal breast cancer history (OR 5.21, 95% CI 4.02 to 6.55, compared with no previous breast cancer), followed by high grade (OR 2.47, 95% CI 1.97 to 3.10, compared with low/intermediate grade), serous histotype (OR 2.33, 95% CI 2.07 to 2.64, compared with other histotypes), advanced (III/IV) FIGO stage (OR 1.89, 95% CI 1.67 to 2.15, compared with stage I/II) and age at diagnosis ≤50 years (OR 1.20, 95% CI 1.01 to 1.42, compared with >50 years).

CONCLUSION

The results of this meta-analysis provide data on features increasing the prior probability of finding BRCA1/2 pathogenic variants that may prove helpful in counselling patients and prioritising testing.

PROSPERO REGISTRATION NUMBER

CRD42021271815.

Risk-reducing salpingo-oophorectomy among Chinese women at increased risk of breast and ovarian cancer

BACKGROUND

Risk-reducing salpingo-oophorectomy (RRSO) is recommended for women at increased risk of breast and ovarian cancer. We launched a prospective study of women receiving RRSO, including those with mutations in genes beyond BRCA1/2.

PATIENTS AND METHODS

80 women were enrolled for RRSO with sectioning and extensively examining the fimbriae (SEE-FIM) protocol between October 2016 and June 2022. The majority of participants had inherited susceptibility gene mutations or a family history suggesting ovarian cancer risk, while patients with isolated metastatic high-grade serous cancer of unknown origin were also included.

RESULTS

Overall, two patients had isolated metastatic high-grade serous cancer with unknown origin, and four patients had family histories but refused to take genetic tests. The rest 74 patients harbored deleterious susceptible gene, including 43 (58.1%) with BRCA1 mutation, and 26 (35.1%) with BRCA2 mutation, respectively. Other mutated genes included ATM (1), BRIP1(1), PALB2(1), MLH1(1) and TP53 (1) in each patient. Among the 74 mutation carriers, three (4.1%) cancers were recognized, one (1.4%) was found to have serous tubal intraepithelial carcinoma (STIC), and five patients (6.8%) was diagnosed with serous tubal intraepithelial lesions (STILs). P53 signature was recognized in 24 patients (32.4%). For other genes, MLH1 mutation carrier had endometrial atypical hyperplasia and p53 signature in fallopian tubes. The germline TP53 mutation carrier had STIC in the surgical specimens. Evidence for precursor escape was also recognized in our cohort.

CONCLUSION

Our study demonstrated clinic-pathological findings of patients at increased risk of breast and ovarian cancer, and expand the clinical application of SEE-FIM protocol.

Homologous recombination deficiency status predicts response to platinum-based chemotherapy in Chinese patients with high-grade serous ovarian carcinoma

BACKGROUND

Homologous Recombination Deficiency (HRD) is a predictive biomarker for ovarian cancer treated with PARP inhibitors or for breast cancer treated with first-line platinum-based chemotherapy. However, limited research is documented on platinum-based treatment prediction with HRD as a biomarker in ovarian cancer patients, especially in the Chinese population.

METHODS

We investigated the association between HRD status and the response of platinum-based chemotherapy in 240 Chinese HGSOC patients.

RESULTS

The Pt-sensitive patients showed higher HRD scores than Pt-resistant ones, but this was not significant(median: 42.6 vs. 31.6, p = 0.086). (Pt)-sensitive rate was higher in HRD + BRCAm tumors and in HRD + BRCAwt tumors (HRD + BRCAm: 97%, p = 0.004 and HRD + BRCAwt: 90%, p = 0.04) compared with 74% in the HRD-BRCAwt tumors. We also found Pt-sensitive patients tend to be enriched in patients with BRCA mutations or non-BRCA HRR pathway gene mutations (BRCA: 93.6% vs 75.4%, p < 0.001; non-BRCA HRR: 88.6% vs 75.4%, p = 0.062). Patients with HRD status positive had significantly improved PFS compared with those with HRD status negative (median PFS: 30.5 months vs. 16.8 months, Log-rank p = 0.001). Even for BRCAwt patients, positive HRD was also associated with better PFS than the HRD-negative group (median: 27.5 months vs 16.8 months, Log-rank p = 0.010). Further, we found patients with pathogenic mutations located in the DNA-binding domain (DBD) of BRCA1 had improved FPS, compared to those with mutations in other domains. (p = 0.03).

CONCLUSIONS

The HRD status can be identified as an independent significance in Chinese HGSOC patients treated with first-line platinum-based chemotherapy.

Using species richness calculations to model the global profile of unsampled pathogenic variants: Examples from BRCA1 and BRCA2

There have been many surveys of genetic variation in BRCA1 and BRCA2 to identify variant prevalence and catalogue population specific variants, yet none have evaluated the magnitude of unobserved variation. We applied species richness estimation methods from ecology to estimate "variant richness" and determine how many germline pathogenic BRCA1/2 variants have yet to be identified and the frequency of these missing variants in different populations. We also estimated the prevalence of germline pathogenic BRCA1/2 variants and identified those expected to be most common. Data was obtained from a literature search including studies conducted globally that tested the entirety of BRCA1/2 for pathogenic variation. Across countries, 45% to 88% of variants were estimated to be missing, i.e., present in the population but not observed in study data. Estimated variant frequencies in each country showed a higher proportion of rare variants compared to recurrent variants. The median prevalence estimate of BRCA1/2 pathogenic variant carriers was 0.64%. BRCA1 c.68_69del is likely the most recurrent BRCA1/2 variant globally due to its estimated prevalence in India. Modeling variant richness using ecology methods may assist in evaluating clinical targeted assays by providing a picture of what is observed with estimates of what is still unknown.

Potential prognostic role of somatic mutations in a set of cancer susceptibility genes in ovarian carcinoma: A follow-up multicentric study from Pakistan

BACKGROUND

Genetic mutations, peritoneal metastasis and frequent development of chemoresistance worsen the prognosis of Ovarian carcinoma.

OBJECTIVE

The objective of the study is to determine mutations in cancer susceptibility genes in relation with chemotherapy response.

METHODS

In this follow up descriptive study, 47 consenting female patients diagnosed with surface epithelial ovarian cancer were observed for six months after completion of chemotherapy to see the treatment response. For genetic analysis, the DNA extraction was done and the genomic regions of different exons of BRCA1/2, PALB2, CHEK2, BAP1, CTNNB1, HOXB13, and PIK3CA were amplified using gene specific primers followed by Sanger Sequencing.

RESULTS

86.7% of the patients were sensitive to chemotherapy whereas 13.3% showed resistance. Genetic variants of BRCA1 in 7%, BRCA2 in 4.7%, PIK3CA in 9.3%, PALB2 in 7%, CHEK2 in 2.3%, BAP1 in 2.3%, and CTNNB1 in 2.3% of the patients were found. There was also a significant association between TNM stage and the treatment response (p< 0.01). Of the patients with no mutations, 90.9% showed chemosensitivity as opposed to 70% in mutations group.

CONCLUSION

Our study exhibits the pivotal role of genetic analysis in predicting the treatment response and paving pathway for patient tailored targeted therapy in Pakistani population.

Overview on population screening for carriers with germline BRCA mutation in China

Carriers with BRCA1/2 germline pathogenic variants are associated with a high risk of breast and ovarian cancers (also pancreatic and prostate cancers). While the spectrum on germline BRCA mutations among the Chinese population shows ethnic specificity, the identification of carriers with germline BRCA mutation before cancer onset is the most effective approach to protect them. This review focused on the current status of BRCA1/2 screening, the surveillance and prevention measures, and discussed the issues and potential impact of BRCA1/2 population screening in China. We conducted literature research on databases PubMed and Google Scholar, as well as Chinese databases CNKI and Wangfang Med Online database (up to 31 March 2022). Latest publications on germline BRCA1/2 prevalence, spectrum, genetic screening as well as carrier counseling, surveillance and prevention were captured where available. While overall 15,256 records were retrieved, 72 publications using germline BRCA1/2 testing were finally retained for further analyses. Germline BRCA1/2 mutations are common in Chinese patients with hereditary breast, ovarian, prostate and pancreatic cancers. Within previous studies, a unique BRCA mutation spectrum in China was revealed. Next-generation sequencing panel was considered as the most common method for BRCA1/2 screening. Regular surveillance and preventive surgeries were tailored to carriers with mutated-BRCA1/2. We recommend that all Chinese diagnosed with breast, ovarian, pancreatic or prostate cancers and also healthy family members, shall undergo BRCA1/2 gene test to provide risk assessment. Subsequently, timely preventive measures for mutation carriers are recommended after authentic genetic counseling.

The first Chinese National Union of Real-world Gynaecological Oncology Research and Patient Management Platform: A retrospective study

OBJECTIVE

To produce high-quality, real-world evidence for oncologists by collating scattered gynaecologic oncology (GO) medical records in China.

DESIGN

Retrospective study.

SETTING

The National Union of Real-world Gynaecological Oncology Research and Patient Management Platform (NUWA platform).

SAMPLE

Patient-centred data pool.

METHODS

The NUWA platform integrated inpatient/outpatient clinical, gene and follow-up data. Data of 11 456 patients with ovarian cancer (OC) were collected and processed using 91 345 electronic medical records. Structured and unstructured data were de-identified and re-collated into a patient-centred data pool using a predefined GO data model by technology-aided abstraction.

MAIN OUTCOME MEASURES

Recent treatment pattern shifts towards precision medicine for OC in China.

RESULTS

Thirteen first-tier hospitals across China participated in the NUWA platform up to 7 December 2021. In total, 3504 (30.59%) patients were followed up by a stand-alone patient management centre. The percentage of patients undergoing breast cancer gene (BRCA) mutation tests increased by approximately six-fold between 2017 and 2018. A similar trend was observed in the administration rate of poly(ADP-ribose) polymerase inhibitors as first-line treatment and second-line treatment after September 2018, when olaparib was approved for clinical use in China.

CONCLUSION

The NUWA platform has great potential to facilitate clinical studies and support drug development, regulatory reviews and healthcare decision-making.

What predicts the clinical benefits of PARP inhibitors in platinum-sensitive recurrent ovarian cancer: A real-world single-center retrospective cohort study from China

Objective

This study assessed the real-world application, effectiveness, and safety of olaparib and niraparib as maintenance therapies in patients with platinum-sensitive recurrent ovarian cancer (PSROC) in China and investigated clinical factors associated with prolonged benefits of poly ADP-ribose polymerase (PARP) inhibitors to help guide clinician treatment-decision making in daily practice.

Methods

This real-world single-center retrospective cohort study was conducted at the Shandong Cancer Hospital and Institute. Archival data of consecutive patients diagnosed with PSROC who achieved a complete response (CR) or partial response (PR) after the last platinum-based chemotherapy and treated with olaparib or niraparib as maintenance therapy from August 2018 to September 2021 were collected.

Results

Overall, 106 women were included in the cohort. Seventy-two (68%) patients were treated with olaparib, while 34 (32%) received niraparib; 99.1% of the patients were diagnosed with high-grade serous carcinoma, and 73.6% had FIGO stages III–IV. Approximately 71.7% of the patients had received PARP inhibitors after the second platinum-based line and 44.3% of the patients achieved a CR in their last platinum-based therapy. The median platinum-free interval (PFI) after the penultimate platinum-based therapy was 10 (95% CI: 10–13.6) months. The median PFS was 21 (95% CI: 13–24.5) months and the median CFI was 22 (95% CI: 16–26.5) months. Consistent with the univariate analysis, the multivariate analysis identified three independent factors associated with prolonged progression-free survival (PFS) and chemotherapy-free interval (CFI): breast cancer susceptibility gene (BRCA) mutant type (p = 0.005 and p = 0.003); PFI ≥12 months (p = 0.01 and p = 0.006); and CR to last platinum-based therapy (p = 0.016 and p = 0.019). It was found that there was no appreciable difference in any grade 3–4 hematological AE between patients who received olaparib and niraparib.

Conclusion

Maintenance treatment with olaparib and niraparib is effective and well tolerated for PSROC patients in real-world clinical practice. Three clinical factors were identified that predicted prolonged survival under maintenance therapy with PARP inhibitors: BRCA mutant type, PFI ≥12 months, and CR to last platinum-based therapy. These findings should be further confirmed with an appropriately powered analysis in studies with larger sample sizes.

Analysis of Competitive Endogenous Mechanism and Survival Prognosis of Serum Exosomes in Ovarian Cancer Patients Based on Sequencing Technology and Bioinformatics

Background: We determined the competitive endogenous in serum exosomes of ovarian cancer patients via sequencing technology and raw signal analysis. We performed an in-depth study of the potential mechanisms of ovarian cancer, predicted potential therapeutic targets and performed survival analysis of the potential targets.

Methods: Serum exosomes from three ovarian cancer patients were used as the experimental group, serum exosomes from three patients with uterine fibroids were used as the control group, and whole transcriptome analysis of serum exosomes was performed to identify differentially expressed long noncoding RNAs (lncRNAs) and mRNAs in ovarian cancer. The miRcode database and miRNA target gene prediction website were used to predict the target genes. Cytoscape software was used to generate a competing endogenous RNA (ceRNA) network of competitive endogenous mechanism of serum exosomes in ovarian cancer, and the R language was used for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses of the target genes. Finally, the TCGA website was used to download clinical and expression data related to ovarian cancer, and the common potential target genes obtained previously were analyzed for survival.

Results: A total of 117 differentially expressed lncRNAs as well as 513 differentially expressed mRNAs (p < 0.05, |log2 fold change (FC)|≥ 1.0) were obtained by combining sequencing data and raw signal analysis, and 841 predicted target genes were reciprocally mapped by combining the data from the miRcode database and miRNA target gene prediction website, resulting in 11 potential target genes related to ovarian cancer (FGFR3, BMPR1B, TRIM29, FBN2, PAPPA, CCDC58, IGSF3, FBXO10, GPAM, HOXA10, and LHFPL4). Survival analysis of the above 11 target genes revealed that the survival curve was statistically significant (p < 0.05) for HOXA10 but not for the other genes. Through enrichment analysis, we found that the above target genes were mainly involved in biological processes such as regulation of transmembrane receptor protein kinase activity, structural molecule activity with elasticity, transforming growth factor-activated receptor activity, and GABA receptor binding and were mainly enriched in signaling pathways regulating stem cell pluripotency, bladder cancer, glycerolipid metabolism, central carbon metabolism of cancer, and tyrosine stimulation to EGFR in signaling pathways such as resistance to enzyme inhibitors.

Conclusions: The serum exosomal DIO3OS-hsa-miR-27a-3p-HOXA10 competitive endogenous signaling axis affects ovarian cancer development and disease survival by targeting dysregulated transcriptional pathways in cancer.

The Features of BRCA1 and BRCA2 Germline Mutations in Hakka Ovarian Cancer Patients: BRCA1 C.536 A>T Maybe a Founder Mutation in This Population

Objective

To investigate the frequencies of BRCA1 and BRCA2 mutations in Chinese Hakka patients with ovarian cancer.

Methods

The protein coding regions and exon intron boundary regions of the BRCA gene were sequenced using genomic DNA isolated from the lymphocytes of patients with next-generation sequencing. The patients’ family history and clinical records were collected.

Results

A total of 195 patients with ovarian cancer were included in the study, and 52 distinct variants of the BRCA gene were identified. It was found that 64 patients (64/195, 32.8%) had BRCA gene mutations, including 32 patients (50.0%) with BRCA1 mutation, 27 patients (42.2%) with BRCA2 mutation, and 5 patients (7.8%) with both mutations. Furthermore, 22 pathogenic mutations were detected in 26 patients, 2 likely pathogenic variants in 2 patients, 12 variants of uncertain significance in 20 patients, and 16 likely benign variants in 24 patients. The mutations were mainly found to occur in exons 8, 14, and 17 of BRCA1 and exons 10, 11, 14, and 15 of BRCA2. The results showed that the BRCA genes possess different mutation hotspots in different ethnic groups. In addition, recurrent mutations were noted in many patients. BRCA1 c.536 A>T, considered a founder mutation, was identified in 10 patients (15.63%, 10/64), followed by BRCA1 c.2635 G>T (6.25%, 4/64) and BRCA2 c.2566 T>C (6.25%, 4/64).

Conclusion

The BRCA1 c.536 A>T could be considered to be a founder mutation in this ovarian cancer population. This recurrent BRCA1 mutation has rarely been observed in other ethnic groups. Our findings are expected to provide valuable data for clinical consultation and for designing individualized treatment for ovarian cancer.

Mutation Landscape of Homologous Recombination Repair Genes in Epithelial Ovarian Cancer in China and Its Relationship With Clinicopathlological Characteristics

OBJECTIVE

The status of homologous recombination repair (HRR) gene mutations and their impact on the survival of patients with Chinese epithelial ovarian cancer (EOC) are still unclear. In this study, we retrospectively analyzed the mutations of HRR genes in tumor tissues and evaluated their values for predicting the survival of Chinese EOC patients.

METHODS

A total of 273 primary EOC patients from five different hospitals between 2015 and 2016 were recruited. All patients received staging surgeries or debulking surgeries combined with systemic platinum-based chemotherapy. DNA was extracted from formalin-fixed, paraffin-embedded sections and analyzed for mutations using a 21-gene panel (including 13 well-known HRR genes) by next-generation sequencing.

RESULTS

High-grade serous carcinoma (HGSOC) accounted for 76.2% of the cohort. A total of 34.1% (93/273) cases had 99 deleterious mutations in 9 HRR genes, namely, BRCA1 (56/273, 20.5%), BRCA2 (20/273, 7.3%), ATM (5/273, 1.8%), RAD51C (5/273, 1.8%), RAD51D (5/273, 1.8%), BRIP1 (2/273, 1.8%), CHEK2 (2/273, 0.7%), FANCI (2/273, 0.7%), and RAD54L (1/273, 0.4%). There is a strong mutual exclusion between HRR genes. The mutation landscape revealed several unappreciated deleterious variants in BRCA1/2 and other HRR genes reported previously. Estimated according to the mutation allele frequency, about 4.8% of the patients had potential somatic HRR gene mutations, which might be underestimated. Moreover, HRR mutations mainly exist in HGSOC (83/208, 39.9%), clear cell (2/30, 6.7%), and endometroid subtypes (8/20, 40%), but not seen in other rare subtypes. BRCA1 mutations tend to be present in younger patients with family history or multiple primary foci. Patients with BRCA1/2 mutations tend to have a longer progression-free survival and overall survival, while other HRR mutation carriers tend to have a shorter progression-free survival, but no significant difference in overall survival.

CONCLUSION

This study revealed the distribution of HRR gene mutations in Chinese EOC tissues. BRCA1/2 account for the majority of HRR gene mutations and predict long prognosis in HGSOC. Non-BRCA HRR mutations also account for a very important proportion and might be associated with poor prognosis in HGSOC. It is suggested that HRR gene mutations need to be detected in EOC tissues and germline status be further clarified in clinical algorithm for potential targeted therapy, genetic screening, and prognosis prediction.

Effects of Neoadjuvant Chemotherapy in Ovarian Cancer Patients With Different Germline BRCA1/2 Mutational Status: A Retrospective Cohort Study

Background

Whether neoadjuvant chemotherapy (NAC) followed by interval debulking surgery (IDS) against primary debulking surgery (PDS) has a differential effect on prognosis due to Breast Cancer Susceptibility Genes (BRCA)1/2 mutations has not been confirmed by current studies.

Methods

All patients included in this retrospective study were admitted to Qilu Hospital of Shandong University between January 2009 and June 2020, and germline BRCA1/2 mutation were tested. Patients in stage IIIB, IIIC, and IV, re-staged by International Federation of Gynecology and Obstetrics (FIGO) 2014, were selected for analysis. All patients with NAC received 1-5 cycles of platinum-containing (carboplatin, cisplatin, or nedaplatin) chemotherapy. Patients who received maintenance therapy after chemotherapy were not eligible for this study. All relevant medical records were collected.

Results

A total of 322 patients were enrolled, including 112 patients with BRCA1/2 mutations (BRCAmut), and 210 patients with BRCA1/2 wild-type (BRCAwt). In the two groups, 40 BRCAmut patients (35.7%) and 69 BRCAwt patients (32.9%) received NAC. The progression-free survival (PFS) of BRCAmut patients was significantly reduced after NAC (median: 14.9 vs. 18.5 months; p=0.023); however, there was no difference in overall survival (OS) (median: 75.1 vs. 72.8 months; p=0.798). Whether BRCAwt patients received NAC had no significant effect on PFS (median: 13.5 vs. 16.0 months; p=0.780) or OS (median: 54.0 vs. 56.4 months; p=0.323). Multivariate analyses in BRCAmut patients showed that the predictors of prolonged PFS were PDS (p=0.001), the absence of residual lesions (p=0.012), and FIGO III stage (p=0.020); Besides, PARP inhibitor was the independent predictor for prolonged OS in BRCAmut patients (p=0.000), for BRCAwt patients, the absence of residual lesions (p=0.041) and history of PARP inhibitors (p=0.000) were beneficial factors for OS prolongation.

Conclusions

For ovarian cancer patients with FIGO IIIB, IIIC, and IV, NAC-IDS did not adversely affect survival outcomes due to different BRCA1/2 germline mutational status.

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

Homologous recombination deficiency (HRD) is an approved predictive biomarker for Poly (ADP-ribose) polymerase inhibitors (PARPi) in ovarian cancer. However, the proportion of positive HRD in the real world and the relationship between HRD status and PARPi in Chinese ovarian cancer patients remain unknown. A total of 67 ovarian cancer patients who underwent PARPi, either olaparib or niraparib, were enrolled and passed inclusion criteria from August 2018 to January 2021 in the Affiliated Cancer Hospital of Nanjing Medical University. HRD status correlation with Progression-free survival (PFS) was analyzed and summarized with a log-rank test. Univariate and multiple cox-regression analyses were conducted to investigate all correlated clinical factors. Approximately 68.7% (46/67) patients were HRD positive and the rest 31.3% (21/67) were HRD negative. The PFS among HRD-positive patients was significantly longer than those HRD-negative patients (medium PFS 9.4 m vs 4.1 m, hazard ratio [HR]: 0.52, 95% CI: [0.38–0.71], p <0.001). Univariate cox-regression found that HRD status, Eastern Cooperative Oncology Group (ECOG) status, BRCA status, previous treatment lines, secondary cytoreductive surgery and R0 resection were significantly associated with PFS after PARPi treatment. After multiple regression correction, HRD status and ECOG were the independent factors to predict PFS (HR: 0.67, 95% CI: [0.49–0.92], p = 0.01; HR: 2.20, 95% CI: [1.14–4.23], p = 0.02, respectively). In platinum sensitivity evaluable subgroup (N = 49), HRD status and platinum sensitivity status remain significant to predict PFS after multiple regression correction (HR: 0.71, 95% CI: [0.51–0.98], p = 0.04; HR: 0.49, 95% CI: [0.24–1.0], p = 0.05, respectively). This is the first real-world study of HRD status in ovarian cancer patients in China, and we demonstrate that HRD is an independent predictive biomarker for PARP inhibitors treatment in Chinese ovarian cancer patients.

Cancer-specific mortality in Asian American women diagnosed with gynecologic cancer: a nationwide population-based analysis

BACKGROUND

Cancer is the leading cause of death in Asian Americans (AA), the fastest-growing U.S. population group. Despite heterogeneity in socioeconomic status and health behaviors by ethnicity, few studies have assessed cancer outcomes across AA ethnic groups. We examined differences in gynecologic cancer mortality between AA ethnic groups and non-Hispanic Whites (NHW).

METHODS

Using the Surveillance, Epidemiology, and End Results database, we identified ovarian (n=69,113), uterine (n=157,340), and cervical cancer cases (n=41,460) diagnosed from 1991-2016. Competing risk regression was used to compare cancer-specific mortality for AAs by ethnicity, using NHW as the reference population.

RESULTS

In adjusted analyses, AAs had a lower risk of ovarian (hazard ratio [HR]: 0.90, 95% CI: 0.86-0.94) and cervical cancer death (HR: 0.80, 95% CI: 0.75-0.87) than NHWs, with stronger associations among those {greater than or equal to}50 years at diagnosis (HRovary: 0.87, 95% CI: 0.82-0.92; HRcervix: 0.74, 95% CI: 0.67-0.81). No overall difference was noted for uterine cancer death (HR: 1.03, 95% CI: 0.97-1.10); however, AAs <50 years at diagnosis had a higher risk of uterine cancer death than NHWs (HR: 1.26, 95% CI: 1.08-1.46). Patterns of cancer mortality were heterogeneous, with Filipino and Chinese women at the highest risk of uterine cancer death and Indian/Pakistani women at the lowest risk of ovarian and cervical cancer death.

CONCLUSIONS

There are significant differences in gynecologic cancer mortality between AAs and NHWs, with heterogeneity by AA ethnicity.

IMPACT

Disaggregated analysis of AA is needed to better understand the burden of gynecologic cancer and identify high-risk groups for cancer prevention efforts.

Probability of detecting germline BRCA1/2 pathogenic variants in histological subtypes of ovarian carcinoma. A meta-analysis

BACKGROUND

Histology restricted genetic predisposition testing of ovarian carcinoma patients is a topic of debate as the prevalence of BRCA1/2 pathogenic variants (PVs) in various histological subtypes is ambiguous. Our primary aim was to investigate the proportion of germline BRCA1/2 PVs per histological subtype. Additionally, we evaluated (i) proportion of somatic BRCA1/2 PVs and (ii) proportion of germline PVs in other ovarian carcinoma risk genes.

METHODS

PubMed, EMBASE and Web of Science were systematically searched and we included all studies reporting germline BRCA1/2 PVs per histological subtype. Pooled proportions were calculated using a random-effects meta-analysis model. Subsets of studies were used for secondary analyses.

RESULTS

Twenty-eight studies were identified. The overall estimated proportion of germline BRCA1/2 PVs was 16.8% (95% CI 14.6 to 19.2). Presence differed substantially among patients with varying histological subtypes of OC; proportions being highest in high-grade serous (22.2%, 95% CI 19.6 to 25.0) and lowest in clear cell (3.0%, 95% CI 1.6 to 5.6) and mucinous (2.5%, 95% CI 0.6 to 9.6) carcinomas. Somatic BRCA1/2 PVs were present with total estimated proportion of 6.0% (95% CI 5.0 to 7.3), based on a smaller subset of studies. Germline PVs in BRIP1, RAD51C, RAD51D, PALB2, and ATM were present in approximately 3%, based on a subset of nine studies.

CONCLUSION

Germline BRCA1/2 PVs are most frequently identified in high-grade serous ovarian carcinoma patients, but are also detected in patients having ovarian carcinomas of other histological subtypes. Limiting genetic predisposition testing to high-grade serous ovarian carcinoma patients will likely be insufficient to identify all patients with a germline PV.

Detection of BRCA1/2 Mutation and Analysis of Clinicopathological Characteristics in 141 Cases of Ovarian Cancer

Breast cancer susceptibility genes 1 and 2 (BRCA1 and BRCA2) are known biomarkers for hereditary ovarian cancer (OC). However, a comprehensive association study between BRCA1/2 mutation spectrum and clinicopathological characteristics in Chinese ovarian cancer patients has not been performed yet to our best knowledge. To fill in this gap, we collected BRCA1/2 sequencing data and clinical information of 141 OC patients from Fujian Cancer Hospital between April 2018 and March 2020. The clinical information includes the age of onset, FIGO staging, pathological types, serum 125 detection level, lymph node metastasis, distant metastasis, the expression of Ki67, and disease history of the patient and his/her family. We then studied their associations by software SciPy 1.0. As a result, we detected pathogenic and potentially pathogenic BRCA1/2 mutations in 27 out of 141 patients (19.15%). Among the 27 patients with mutations, the major type of mutation was frameshift, which was observed in 12 patients (44.4%). Most of the mutation sites were distributed on exons 10 and 11, accounting for 48.1% (13/27) and 22.2% (6/27), respectively. In terms of histological classification, high-grade serous adenocarcinoma accounted for 79.43% of the 141 samples. The BRCA1/2 mutation group was all high-grade serous adenocarcinoma, accounting for 24.1% (27/112) of this group. The incidence of pathogenic mutation in BRCA1 and BRCA2 was 15.7% (19/112) and 7.27% (8/112), respectively. Univariate analysis showed that there was no significant difference between patients with BRCA1/2 mutation and others in age-of-onset, FIGO stage, pathological types, serum CA125 level, lymph node metastasis, the expression of Ki67, and personal and family disease history. However, there are significant differences between patients with BRCA1/2 mutation and others in distant metastasis rate (P < 0.002). In addition, the BRCA1/2 mutation rate in 141 ovarian cancer patients was similar to those reported in other studies in China. Nearly one-quarter of high-grade serous carcinomas had BRCA1/2 mutations. In conclusion, our study indicated that patients with BRCA1/2 mutations were more likely to undergo distant metastasis, and BRCA1/2 mutation detection should be performed for patients with high-grade serous adenocarcinoma to guide the selection of clinical treatment options.

Prevalence and clinical characterization of BRCA1 and BRCA2 mutations in Korean patients with epithelial ovarian cancer

This study was performed to investigate the prevalence, clinical characteristics, and treatment response according to BRCA1 and BRCA2 (BRCA) mutations in Korean patients with epithelial ovarian cancer (EOC). Two‐hundred and ninety‐eight Korean women diagnosed with high‐grade serous and/or endometrioid EOC from 2010 to 2015 were tested for germline and 86 specimens for somatic BRCA mutations, regardless of the family history. Clinical characteristics including survival outcomes were compared in patients with and without BRCA mutations (NCT02963688). A total of 43 different germline BRCA mutations were identified in 78 patients among 298 patients (26.2%). Somatic BRCA mutations were identified in 11 (12.8%) patients among patients without germline BRCA mutations. Haplotype analysis demonstrated no founder mutations in our Korean patient cohort. Insignificant differences in age at diagnosis, primary site, and residual disease after surgery were observed between patients with and without BRCA mutations. In multivariate analysis for overall survival (OS), the presence of BRCA mutation was significantly associated with OS (P = .049) in addition to platinum sensitivity (P < .001), indicating it is an independent prognostic factor for survival regardless of platinum sensitivity to first‐line chemotherapy. In addition, a higher response rate to subsequent chemotherapy after recurrence was observed in EOC patients with BRCA mutations resulting in better OS. In the current study, the prevalence of BRCA mutations in Korean patients with EOC was higher than previously reported in other ethnic groups. We demonstrated characteristics and treatment response in Korean EOC patients with BRCA mutations. These findings may provide valuable information to be considered in future clinical trials including Asian patients.

Research progress on the association between environmental pollutants and the resistance mechanism of PARP inhibitors in ovarian cancer

The occurrence and progression of ovarian cancer are closely related to genetics and environmental pollutants. Poly(ADP-ribose) polymerase (PARP) inhibitors have been a major breakthrough in the history of ovarian cancer treatment. PARP is an enzyme responsible for post-translational modification of proteins and repair of single-stranded DNA damage. PARP inhibitors can selectively inhibit PARP function, resulting in a synthetic lethal effect on tumor cells defective in homologous recombination repair. However, with large-scale application, drug resistance also inevitably appears. For PARP inhibitors, the diversity and complexity of drug resistance mechanisms have always been difficult problems in clinical treatment. Herein, we mainly summarized the research progress of DNA damage repair and drug resistance mechanisms related to PARP inhibitors and the impact of environmental pollutants on DNA damage repair to aid the development prospects and highlight urgent problems to be solved.

Identifying Sequence Variants of 18 Hereditary Ovarian Cancer-Associated Genes in Chinese Epithelial Ovarian Cancer Patients

Objectives

The causes of ovarian cancer (OC) have been confirmed to be closely related to genetic factors. Identifying sequence variants of hereditary ovarian cancer (HOC) susceptibility genes can increase clinical surveillance, facilitate early detection, and provide personalized treatment for patients. This study is aimed at investigating the variation frequency of HOC susceptibility genes in the Chinese population and providing information for the etiology and genetics of OC.

Methods

118 epithelial OC patients were recruited in this clinical study. Variants of 18-gene panel were detected in blood samples by next-generation sequencing (NGS) technology.

Results

Overall, 36.44% (43/118) of patients carried at least one pathogenic variant. Among these, BRCA1 pathogenic variants were detected in 31 (26.27%) patients, and 5 (4.24%) patients carried pathogenic variants of BRCA2. Moreover, 27.12% (32/118) of patients carried variants of unknown significance (VUSs). Importantly, we detected eight variants that were not reported previously.

Conclusions

Our study enlarged the spectrum of HOC-associated gene sequence variants in the Chinese population and also proved the necessity of multigene testing in epithelial OC patients. The identification of patients with HOC will allow family members to undergo cascade testing where identification of unaffected carriers can facilitate early detection, risk reduction, or prevention of OC and ultimately improve long-term outcomes.

Identification of BRCA1:c.5470_5477del as a Founder Mutation in Chinese Ovarian Cancer Patients

Predisposition of germline BRCA1/2 mutations (gBRCAMUT ) increases the risk of breast and ovarian cancer in females, but the mutation prevalence and spectrum are highly ethnicity-specific with different recurrent mutations being reported in different populations. Hereby, we performed hybridization-based target sequencing of BRCA1/2 in 530 ovarian cancer patients from Henan, the central region of China, followed by haplotype analysis of six short tandem repeat (STR) markers in the patients with recurrent mutations to determine their founder effect. About 28.3% (150/530) of the OC patients in our cohort harbored gBRCAMUT ; of the 151 mutations, 117 in BRCA1 and 34 in BRCA2, identified in this study, BRCA1:c.5470_5477del, c.981_982del, and c.4065_4068del are the top three mutants, recurrently detected in eight, seven, and six independent patients respectively. Haplotype analysis identified a region of 0.6 MB genomic length covering BRCA1 highly conserved across all eight carriers of BRCA1:c.5470_5477del, but not c.981_982del, suggesting a consequence of founder effect. Retrospective analysis in a subgroup of serous ovarian cancer patients revealed gBRCAMUT status was not associated with the progression-free survival (PFS); instead, an expression of Ki-67% ≥50% was associated with a shorter PFS (p = 0.041). In conclusion, patients with pathogenic or likely pathogenic gBRCAMUT account for 28.3% of the OC cases from Henan, and BRCA1:c.5470_5477del, the most frequently detected mutation in Henan patients, is a founder mutation in the population.

Next Generation Sequencing-Based Germline Panel Testing for Breast and Ovarian Cancers in Pakistan

Background:

Pathogenic germline mutations in BRCA1/2 constitute the majority of hereditary breast and/or ovarian cancers worldwide. Incidence and mortality rate of breast and ovarian cancers in Pakistani women is high. Thus, to establish the diagnosis for targeted therapy in Pakistan, we conducted Next-generation sequencing-based germline testing for the detection of BRCA1/2 oncogenic variants associated with breast and ovarian cancer subtype.

Methods:

Peripheral blood of 24 women, diagnosed with breast and epithelial ovarian cancers, was taken from the recruited cases with the consent of performing germline genetic testing. DNA was isolated from the peripheral blood and subjected to indexed BRCA Panel libraries. Targeted NGS was performed for all coding regions and splicing sites of BRCA1 and BRCA2 genes using AmpliSeq for Illumina BRCA Panel and Illumina MiSeq sequencer (placed at AFIP). Analysis of the sequencing results has been done by using Illumina bioinformatics tools.

Results:

We detected 421 variants having a quality score of 100 in all cases under study. The list of identified variants in BRCA1 and BRCA2 genes was narrowed down after filtering out those which did not pass q30 and those with a minor allele frequency (MAF) > 0.05 based on gnomAD browser. To classify these variants, clinical significance was predicted using external curated databases. As a result, we interpreted (n = 4) 16.7% pathogenic variants in BRCA1 and (n = 6) 25% variants of uncertain significance (VUS) in both genes. Descriptive statistics depicted that the age and BMI of BRCA positive cases are less than BRCA negative cases.

Conclusion:

Our findings exhibit an initial report for the NGS based cancer genetic testing in Pakistan. This will enable us to pursue screening and diagnosis of hereditary BRCA mutation utilizing the latest state-of-the-art technique locally available in Pakistan ultimately resulting in targeted cancer therapy.

Germline and tumor BRCA1/2 mutations in Chinese high grade serous ovarian cancer patients

Background

Studies on the prevalence of BRCA1/2 mutations in ovarian cancer mainly focused on germline single-nucleotide variant (SNV)/insertion/deletion (indel). The status of large genomic rearrangement (LRG) and somatic mutation were poorly investigated.

Methods

Paired blood and tumor DNA from an unselected cohort of 115 Chinese high grade serous ovarian cancer (HGSOC) patients were collected and analyzed for BRCA1/2 SNV and indel by NGS. BRCA1/2 LRG was detected by MLPA. Clinicopathological characteristics including age at diagnosis, FIGO stage, family history and follow-up data were collected for further analysis.

Results

A total of 115 HGSOC patients were screened. Among them, 30 (26.1%) had germline BRCA1/2 mutations, including 19 (16.5%) SNV/indels, 5 (4.3%) LGRs in BRCA1, and 6 (5.2%) SNV/indels in BRCA2. Ten (8.7%) had somatic BRCA1/2 mutations, including 5 (4.3%) in BRCA1 and 5 (4.3%) in BRCA2. The entire tumor BRCA1/2 mutation frequency was 34.8%. No patients were found with two or more deleterious BRCA1/2 mutations. The proportion of germline (66.7%) and tumor (75%) mutation carriers was significantly increased for patients with family history when compared with those without (P<0.05). Patients with germline BRCA1/2 mutation appeared to be younger than non-carriers (mean age, 50.9 vs. 54.4 years, P=0.004) and somatic mutation carriers (mean age, 50.9 vs. 58.7 years, P=0.009). No significant association was found between BRCA1/2 status and clinicopathological characteristics including stage and family history of other cancer than breast and ovarian cancer. In univariate and Cox regression analysis, patients with tumor BRCA1/2 mutations had significant improvements than non-carriers in overall survival in the first two years after surgery (P<0.05). No significant impacts were found between various mutation status in PFS.

Conclusions

There is a high germline and tumor BRCA1/2 mutation incidences in Chinese HGSOC patients. Germline mutations were associated with family history and age at diagnosis, whereas somatic mutations were not. In our study, tumor BRCA1/2 mutations showed a time-depended improved survival outcome. A larger cohort should be examined to clarify the relation between BRCA1/2 mutation and survival outcomes.

Homologous recombination repair gene mutations show no survival benefits in Chinese high-grade serous ovarian cancer patients

Background

The purpose of our study was to identify germline and somatic homologous recombination repair (HRR) pathway gene mutations and their clinical-prognostic impact in Chinese high-grade serous ovarian cancer (HGSC) patients.

Methods

We applied next-generation sequencing (NGS) in consecutive patients who underwent primary surgery for HGSC in November and December 2015 at our institution. Paired peripheral blood (or para-carcinoma tissue) samples and tumor samples from 42 Chinese women were tested to identify both germline and somatic deleterious mutations through all exons in BRCA1/2 and 22 other core HRR genes. Clinic-pathological data were collected until February, 2020. Associations between HRR gene mutations and clinical characters and outcomes were also evaluated.

Results

Deleterious germline HRR mutations were identified in 16.7% (7/42) of the HGSC patients. One patient had both germline BRCA2 and ATM mutations. Six patients had only somatic mutations, increasing the HRR mutation rate to 31.0% (13/42). Neither germline nor somatic HRR gene mutations were related with residual disease (P=0.233) nor platinum sensitivity (P=0.851). In the univariate and multivariate analyses, germline HRR gene mutation status was not associated with progression-free survival (PFS) or overall survival (OS). In addition, no prognostic differences between somatic HRR mutated patients and wild-type patients were found.

Conclusions

Our results suggest that the HRR gene defect was not associated with improved survival in our Chinese HGSC patient cohort.

Frequency of germline BRCA1/2 mutations and association with clinicopathological characteristics in Turkish women with epithelial ovarian cancer

AIM

This study aims to determine the frequency of germline BRCA 1/2 mutations in Turkish women with epithelial ovarian cancer (EOC) and evaluate its relationship with clinicopathological characteristics.

METHODS

In this cross-sectional study, all women with recently diagnosed EOC presenting to Zekai Tahir Burak Women's Health Training and Research Hospital Medical Oncology Clinic between 2016 and 2019 were referred for BRCA testing. Peripheral blood samples were obtained from 76 patients applying to Medical Genetics and BRCA1/2 genes were sequenced using next-generation sequencing. The American College of Medical Genetics and Genomics 2015 criteria were followed for classification of genetic variants.

RESULTS

Twenty-four women (31.6%) had pathogenic germline BRCA1/2 mutations. Of these, 17 patients (22.4%) harbored germline BRCA1 mutations and 7 (9.2%) had BRCA2 mutations. When we compared the patients with and without BRCA mutations, there was significant difference in terms of family history (41.7% vs 9.6%, respectively, P = .001). Among all patients, 15 (19.7%) had history of breast or ovarian cancer in first- or second-degree relatives. Germline BRCA1/2 mutations were detected in 66.7% of patients with family history, while these mutations were found in 22.9% of patients without family history (P = .001).

CONCLUSION

In this sample 31.6% of Turkish women with EOC harbored germline BRCA1/2 mutations, which seems higher compared to other ethnic groups except for the Ashkenazi Jews population. All women with EOC should be referred for BRCA testing regardless of family history, age at diagnosis, and histological subtype.

An Open-label, Multicenter, Single-arm, Phase II Study of Fluzoparib in Patients with Germline BRCA1/2 Mutation and Platinum-sensitive Recurrent Ovarian Cancer

PURPOSE

Fluzoparib (PARP inhibitor) showed promising antitumor activity for advanced ovarian cancer in a phase I study. This study aimed to assess the efficacy and safety of fluzoparib in patients with germline BRCA1/2-mutated recurrent ovarian cancer.

PATIENTS AND METHODS

This open-label, multicenter, single-arm, phase II study enrolled patients with platinum-sensitive recurrent ovarian cancer and germline BRCA1/2 mutation who had previously received two to four lines of platinum-based chemotherapy. Fluzoparib 150 mg was administered orally twice daily. The primary endpoint was independent review committee (IRC)-assessed objective response rate per RECIST v1.1.

RESULTS

A total of 113 patients were enrolled and received at least one dose of fluzoparib. As of data cutoff on March 21, 2020, the median follow-up period was 15.9 months (interquartile range, 13.5-18.5). The IRC- and investigator-assessed objective response rates were 69.9% [95% confidence interval (CI), 60.6-78.2] and 70.8% (95% CI, 61.5-79.0), respectively. The objective response rates were similar across all prespecified subgroups. The median IRC- and investigator-assessed progression-free survival was 12.0 months (95% CI, 9.3-13.9) and 10.3 months (95% CI, 9.2-12.0), respectively. The 12-month survival rate was 93.7% (95% CI, 87.2-96.9). Grade ≥3 adverse events occurred in 63.7% (72/113) of the patients, with the most common one being anemia/decreased hemoglobin. Adverse events that led to treatment interruption, dose reduction, and discontinuation occurred in 39.8%, 34.5%, and 0.9% of patients, respectively. One treatment-related death occurred.

CONCLUSIONS

Fluzoparib demonstrated promising antitumor activity and acceptable safety profile in germline BRCA1/2-mutated, platinum-sensitive relapsed ovarian cancer. Thus, fluzoparib might be a novel treatment option for this population.

Niraparib maintenance therapy in patients with platinum-sensitive recurrent ovarian cancer using an individualized starting dose (NORA): a randomized, double-blind, placebo-controlled phase III trial☆

BACKGROUND

This study evaluated maintenance treatment with niraparib, a potent inhibitor of poly(ADP-ribose) polymerase 1/2, in patients with platinum-sensitive recurrent ovarian cancer.

PATIENTS AND METHODS

In this phase III, double-blind, placebo-controlled study conducted at 30 centers in China, adults with platinum-sensitive recurrent ovarian cancer who had responded to their most recent platinum-containing chemotherapy were randomized 2 : 1 to receive oral niraparib (300 mg/day) or matched placebo until disease progression or unacceptable toxicity (NCT03705156). Following a protocol amendment, patients with a bodyweight <77 kg or a platelet count <150 × 10³/μl received 200 mg/day, and all other patients 300 mg/day, as an individualized starting dose (ISD). Randomization was carried out by an interactive web response system and stratified by BRCA mutation, time to recurrence following penultimate chemotherapy, and response to most recent chemotherapy. The primary endpoint was progression-free survival (PFS) assessed by blinded independent central review.

RESULTS

Between 26 September 2017 and 2 February 2019, 265 patients were randomized to receive niraparib (n = 177) or placebo (n = 88); 249 patients received an ISD (300 mg, n = 14; 200 mg, n = 235) as per protocol. In the intention-to-treat population, median PFS was significantly longer for patients receiving niraparib versus placebo: 18.3 [95% confidence interval (CI), 10.9-not evaluable] versus 5.4 (95% CI, 3.7-5.7) months [hazard ratio (HR) = 0.32; 95% CI, 0.23-0.45; P < 0.0001], and a similar PFS benefit was observed in patients receiving an ISD, regardless of BRCA mutation status. Grade ≥3 treatment-emergent adverse events occurred in 50.8% and 19.3% of patients who received niraparib and placebo, respectively; the most common events were neutrophil count decreased (20.3% versus 8.0%) and anemia (14.7% versus 2.3%).

CONCLUSIONS

Niraparib maintenance treatment reduced the risk of disease progression or death by 68% and prolonged PFS compared to placebo in patients with platinum-sensitive recurrent ovarian cancer. Individualized niraparib dosing is effective and safe and should be considered standard practice in this setting.

Age-related copy number variations and expression levels of F-box protein FBXL20 predict ovarian cancer prognosis

About 70% of ovarian cancer (OvCa) cases are diagnosed at advanced stages (stage III/IV) with only 20–40% of them survive over 5 years after diagnosis. A reliably screening marker could enable a paradigm shift in OvCa early diagnosis and risk stratification. Age is one of the most significant risk factors for OvCa. Older women have much higher rates of OvCa diagnosis and poorer clinical outcomes. In this article, we studied the correlation between aging and genetic alterations in The Cancer Genome Atlas Ovarian Cancer dataset. We demonstrated that copy number variations (CNVs) and expression levels of the F-Box and Leucine-Rich Repeat Protein 20 (FBXL20), a substrate recognizing protein in the SKP1-Cullin1-F-box-protein E3 ligase, can predict OvCa overall survival, disease-free survival and progression-free survival. More importantly, FBXL20 copy number loss predicts the diagnosis of OvCa at a younger age, with over 60% of patients in that subgroup have OvCa diagnosed at age less than 60 years. Clinicopathological studies further demonstrated malignant histological and radiographical features associated with elevated FBXL20 expression levels. This study has thus identified a potential biomarker for OvCa prognosis.

Modeling the Diversity of Epithelial Ovarian Cancer through Ten Novel Well Characterized Cell Lines Covering Multiple Subtypes of the Disease

Cancer cell lines are amongst the most important pre-clinical models. In the context of epithelial ovarian cancer, a highly heterogeneous disease with diverse subtypes, it is paramount to study a wide panel of models in order to draw a representative picture of the disease. As this lethal gynaecological malignancy has seen little improvement in overall survival in the last decade, it is all the more pressing to support future research with robust and diverse study models. Here, we describe ten novel spontaneously immortalized patient-derived ovarian cancer cell lines, detailing their respective mutational profiles and gene/biomarker expression patterns, as well as their in vitro and in vivo growth characteristics. Eight of the cell lines were classified as high-grade serous, while two were determined to be of the rarer mucinous and clear cell subtypes, respectively. Each of the ten cell lines presents a panel of characteristics reflective of diverse clinically relevant phenomena, including chemotherapeutic resistance, metastatic potential, and subtype-associated mutations and gene/protein expression profiles. Importantly, four cell lines formed subcutaneous tumors in mice, a key characteristic for pre-clinical drug testing. Our work thus contributes significantly to the available models for the study of ovarian cancer, supplying additional tools to better understand this complex disease.

Prevalence of Tissue BRCA Gene Mutation in Ovarian, Fallopian Tube, and Primary Peritoneal Cancers: A Multi-Institutional Study

BACKGROUND AND OBJECTIVE

Ovarian, fallopian tube, or primary peritoneal cancer patients with BRCA gene mutation have enhanced sensitivity to platinum-based regimens and PARP inhibitors. However, the knowledge regarding BRCA mutation in Thai patients is limited. This study aimed at identifying the prevalence and characteristics of somatic and germline BRCA 1 and 2 mutations in Thai patients with these cancers.

MATERIALS AND METHODS

The paraffin blocks of tumors with histology of high grade serous, high grade endometrioid, or clear cell carcinoma obtained between June 2016 and December 2017 were analyzedto evaluate BRCA mutation using next-generation sequencing system. Blood or normal tissue paraffin blocks of positive patients were further tested for germline BRCA mutation.

RESULTS

Tissue paraffin blocks of 178 patients were collected but only 139 were analyzed. Positive BRCA mutation was identified in 24 patients (17.3%): BRCA1 in 13 cases, BRCA2 in 10 cases, and BRCA1 and 2 in the rest one. Germline mutation study in blood or normal tissue in 23 positive patients revealed BRCA mutation in 14 cases, BRCA1 in 8 cases and BRCA 2  in 6 cases. Overall, the prevalence of somatic and germline mutation was 6.5% (9 out of 138 patients) and 8.7% (14 out of 138 patients), respectively. The most common histology associated with BRCA mutation was high grade serous cancer (27.3%). No significant difference was found between patients with or without BRCA mutation in terms of stage, outcome, platinum status, and survival outcome.

CONCLUSION

BRCA mutation was demonstrated in less than 10% of Thai ovarian cancer patients. Higher rate of mutation was found in high grade serous cancer.
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Patient-derived ovarian cancer organoids capture the genomic profiles of primary tumours applicable for drug sensitivity and resistance testing

The use of primary patient-derived organoids for drug sensitivity and resistance testing could play an important role in precision cancer medicine. We developed expandable ovarian cancer organoids in < 3 weeks; these organoids captured the characteristics of histological cancer subtypes and replicated the mutational landscape of the primary tumours. Seven pairs of organoids (3 high-grade serous, 1 clear cell, 3 endometrioid) and original tumours shared 59.5% (36.1–73.1%) of the variants identified. Copy number variations were also similar among organoids and primary tumours. The organoid that harboured the BRCA1 pathogenic variant (p.L63*) showed a higher sensitivity to PARP inhibitor, olaparib, as well as to platinum drugs compared to the other organoids, whereas an organoid derived from clear cell ovarian cancer was resistant to conventional drugs for ovarian cancer, namely platinum drugs, paclitaxel, and olaparib. The overall success rate of primary organoid culture, including those of various histological subtypes, was 80% (28/35). Our data show that patient-derived organoids are suitable physiological ex vivo cancer models that can be used to screen effective personalised ovarian cancer drugs.

Germline and Somatic BRCA1/2 Mutations in 172 Chinese Women With Epithelial Ovarian Cancer

Objective: Despite several nationwide cohort studies of germline BRCA1/2 mutations and several small cohort studies of somatic BRCA1/2 mutations in Chinese epithelial ovarian cancer (EOC) patients, little is known about the impact of these findings on survival outcomes in this population. In this study of 172 retrospectively recruited Chinese EOC patients, germline and somatic BRCA1/2 mutations and their value for predicting survival outcomes were evaluated.

Methods: Unselected patients who visited the study center from January 1, 2011, to January 1, 2015, were recruited and asked to provide peripheral blood samples for this study if they were pathologically confirmed to have primary EOC. All patients received staging surgeries or debulking surgeries involving systemic platinum-based chemotherapy, and the patients were then followed up to December 1, 2017. DNA was extracted from formalin-fixed, paraffin-embedded (FFPE) sections and peripheral blood and sequenced for somatic and germline testing, respectively. The demographic and clinicopathological characteristics of the patients were collected to analyze the distribution of BRCA mutations in subgroups. Survival outcomes were compared among various BRCA mutation statuses using univariate and multivariate models.

Results: In 58 (33.7%) patients, 63 variants were identified, including variants of unknown significance (VUS) in 18 patients (10.5%) and pathogenic or likely pathogenic variants in a partially overlapping set of 41 patients (23.8%). Germline BRCA mutations, somatic BRCA mutations, BRCA1 mutations in general, and BRCA2 mutations in general were found in 35 (20.3%), 7 (4.1%), 28 (16.3%), and 13 (7.6%) patients, respectively. Five recurrent mutations were identified. Personal and family cancer histories as well as hereditary breast and ovarian cancer (HBOC) criteria were associated with deleterious BRCA mutations both overall and in the germline specifically, whereas only age at diagnosis of EOC was associated with somatic BRCA mutations. In univariate and Cox regression analyses, patients with BRCA1/2 mutations in general had significant improvements in progression-free survival (PFS) and overall survival (OS).

Conclusions: In Chinese EOC patients, the distributions and risk factors associated with germline and somatic BRCA1/2 mutations were similar to those previously reported in international studies. Deleterious BRCA mutations in general were associated with improved survival outcomes in this cohort.

Expression of PD-L1 in ovarian cancer and its synergistic antitumor effect with PARP inhibitor

BACKGROUND

Ovarian cancer samples were studied to determine the expression of programmed death ligand-1 (PD-L1) and its relationship with prognosis, and to explore the effect and potential mechanism of a PARP inhibitor combined with PD-L1 monoclonal antibody for the treatment of ovarian cancer.

MATERIALS AND METHODS

PD-L1 expression in paraffin-embedded tissues of ovarian cancer was detected by immunohistochemistry (IHC). Flow cytometry was used to detect PD-L1 expression in TILs. Furthermore, we investigated the mechanism of the upregulation of PD-L1 expression by PARP inhibitors in vitro and verified the combined effect in vivo.

RESULTS

Our study demonstrated that PD-L1 expression in ovarian cancer tissues was associated with the FIGO stage (P = 0.026). OS was significantly lower in high PD-L1 expression group than in the low expression group (P = 0.0005, HR = 2.689), PD-L1 high expression (P = 0.023, HR = 2.275) and FIGO stage (P = 0.024, HR = 11.229) were independent risk factors affecting the survival and prognosis of ovarian cancer patients. Flow cytometry test suggested that PD-L1⁺ expression was negatively correlated with CD8⁺ T cell count in ovarian cancer cells (P = 0.054, r = -0.624). In vitro experiments revealed that PD-L1 expression of ovarian cancer cell lines was upregulated after intervention with PARP inhibitors through the Chk1 pathway. The results of in vivo experiments suggested that the growth volume and quality of tumors in the combination group were significantly lower than those in control group (P < 0.05).

CONCLUSIONS

PARP inhibitors could induce upregulation of PD-L1 expression by promoting phosphorylation of chk1. Antagonistic PD-L1 could reverse the inhibitory effect of PARP inhibitors on CD8⁺T cells, and had synergistic antitumor effect with PARP inhibitors.

Comprehensive profiling of BRCA1 and BRCA2 variants in breast and ovarian cancer in Chinese patients

The identification and interpretation of germline BRCA1/2 variants become increasingly important in breast and ovarian cancer (OC) treatment. However, there is no comprehensive analysis of the germline BRCA1/2 variants in a Chinese population. Here we performed a systematic review and meta-analysis on such variants from 94 publications. A total of 2,128 BRCA1/2 variant records were extracted, including 601 from BRCA1 and 632 from BRCA2. In addition, 414, 734, 449, and 307 variants were also recorded in the BIC, ClinVar, ENIGMA, and UMD databases, respectively, and 579 variants were newly reported. Subsequent analysis showed that the overall germline BRCA1/2 pathogenic variant frequency was 5.7% and 21.8% in Chinese breast and OC, respectively. Populations with high-risk factors exhibited a higher pathogenic variant percentage. Furthermore, the variant profile in Chinese is distinct from that in other ethnic groups with no distinct founder pathogenic variants. We also tested our in-house American College of Medical Genetics-guided pathogenicity interpretation procedure for Chinese BRCA1/2 variants. Our results achieved a consistency of 91.2-97.6% (5-grade classification) or 98.4-100% (2-grade classification) with public databases. In conclusion, this study represents the first comprehensive meta-analysis of Chinese BRCA1/2 variants and validates our in-house pathogenicity interpretation procedure, thereby providing guidance for further PARP inhibitor development and companion diagnostics in the Chinese population.

Germline mutations in Thai patients with nonmucinous epithelial ovarian cancer

BACKGROUND

Genetic testing is widely recommended for all epithelial ovarian cancer (EOC) patients. However, an increased probability of identifying germline mutations has been reported in selected patients with risk factors such as a family history or personal history of cancer and high-grade serous carcinoma (HGSC) subtype. HGSC has been reported to be the most common subtype of EOC worldwide (approximately 70%). However, this subtype is less prevalent in Thai patients (reported as only 20%). The difference in the distribution of various subtypes of EOC may reflect the incidence of germline mutations in Thai EOC patients.

AIM

To evaluate the frequencies of germline mutations in EOC patients and to compare the frequencies in those with and without clinical risk factors for hereditary ovarian cancer.

METHODS

This cross-sectional study included 112 nonmucinous EOC patients who underwent primary surgery at our tertiary care hospital. Clinical risk factors for hereditary ovarian cancer were defined as follows: Age below 40 years, a significant family history of cancer, synchronous ovarian and endometrial cancer, and HGSC. Comprehensive germline mutations were detected by next-generation sequencing.

RESULTS

Of a total of 112 patients, 82 (73.2%) patients had ≥ 1 risk factor and 30 (26.8%) patients had no risk factors. Germline mutations were detected in 26 patients: 20 (17.8%) patients had BRCA1/2 mutations, but 6 (5.4%) patients had mutations in other genes, including 1 in MLH1, 1 in MSH2, 1 in RAD51C, 2 in ATM and 1 in CDH1. Germline mutations were only detected in patients with risk factors (26 of 82, 31.7%), not in patients without risk factors (P < 0.001). A significant family history of cancer and HGSC were the only two significant risk factors associated with a higher proportion of germline mutations (56.3% vs 10% for those with and without a history of cancer, respectively, 40.8% vs 9.5% for those with and without HGSC). Germline BRCA mutations were detected in 38.8% of patients with HGSC but in only 1.6% of those with non-HGSC. An age below 40 years, personal history of breast cancer, and synchronous ovarian and endometrial cancer were not significant factors (14.3% vs 23.5%, 33.3% vs 21%, 22.2% vs 22.3%).

CONCLUSION

Approximately one-third of EOC patients with risk factors had germline mutations. Almost all germline BRCA mutations were found in patients with the HGSC subtype. Selected patients with HGSC and a family history of cancer should be initially considered for genetic analysis in Thailand.

Pathological findings following risk-reducing salpingo-oophorectomy in BRCA mutation carriers: A systematic review and meta-analysis

OBJECTIVE

To evaluate the benefit of risk-reducing salpingo-oophorectomy (RRSO) by estimating the pathological positive rate of occult lesions, including serous tubal intraepithelial carcinoma (STIC) and occult cancers (OCCs).

METHODS

BRCA1/2 mutation carriers who underwent RRSO in a Chinese study center between 2014 and 2018 were included. A literature review was performed, followed by a meta-analysis of the literature to further validate the findings.

RESULTS

Twenty-four BRCA1/2 mutation carriers who underwent RRSO were identified; one patient (4.2%) had STIC, and one patient (4.2%) had occult fallopian tube cancer complicated by STIC. Thirty-four articles were ultimately included in the meta-analysis. Of the reported cases of OCC, 61.3% occurred in the fallopian tubes and 32.3% in the ovaries, and 81.5% were in the early stages. The estimated rate of overall pathological positive events was 5%. The estimated rates of overall STIC events and OCC were 1% and 3%, respectively. The rates of STIC and OCC were 1% and 3%, respectively, for BRCA1 mutation carriers and 1% and 1%, respectively, for BRCA2 mutation carriers. No significant difference was observed between the results of a routine examination of pathological sections and those of the Sectioning and Extensively Examining the Fimbriae (SEE-FIM) protocol.

CONCLUSIONS

This study is the first report of RRSO results in China. In this systematic review, the positive rates of STIC or OCC after RRSO were no more than 3%, which are 200-fold higher than the risk of the general population. The use of a strict SEE-FIM protocol would likely increase positive results.

A family pedigree of malignancies associated with BRCA1 pathogenic variants: a reflection of the state of art in China

Background

Little is known about the status of genetic counseling for ovarian cancer in China.

Case presentation

We report a four-generation Chinese family with several types of cancer. The proband was a patient with high-grade serous ovarian cancer (HGSOC) who was found to harbor a pathogenic BRCA1 variant. Cosegregation analysis identified 7 of 9 relatives with the same deleterious variant. One month after the genetic test, one female carrier 54 years of age was diagnosed with stage IVB HGSOC, and another female 55 years of age accepted risk-reducing salpingo-oophorectomy, which revealed occult cancer of the fallopian tube (Stage IA).

Conclusions

Genetic counseling and testing for ovarian cancer in China have fallen behind international trends. Innovative studies and practices are urgently needed to establish models for cancer screening, prevention and treatment.

Germline and somatic mutations of multi-gene panel in Chinese patients with epithelial ovarian cancer: a prospective cohort study

Background

Multiple targeted gene sequencing is seldom performed in both germline and somatic testing for ovarian cancer. This study is to evaluate the specific genetic alterations, including both somatic and germline mutations, in Chinese patients with epithelial ovarian cancer (EOC) in a prospective cohort study.

Materials and methods

Mutations in a customed 21-gene panel that included BRCA1, BRCA2, and 19 other tumor suppressor genes related to homologous recombination (HR) deficiency or non-HR deficiency were detected by targeted exon capture and next-generation sequencing (NGS) technology across all coding exons and exon-intron (±20 base pairs) boundaries. Patients were enrolled consecutively and unselectively without age or family history consideration. Sixty-two unselected patients with epithelial ovarian cancer were enrolled in our study to be tested for paired somatic and germline mutations. All patients were tested using a 21-gene panel that included BRCA1, BRCA2, CHEK2, PALB2, BRIP1, TP53, PTEN, STK11, CDH1, ATM, BARD1, MLH1, MRE11A, MSH2, MSH6, MUTYH, NBN, PMS1, PMS2, RAD50, and RAD51C.

Results

Mutation analysis revealed that 77.4% (48/62) of patients carried one or more of 64 identified genetic alterations, including 19 germline and 45 somatic deleterious mutations. Twelve individuals shared both germline and somatic mutations. BRCA mutants existed in 17 of 62 (27.4%) patients. Of the 64 mutations detected, 46 (74.2%) were in 7 other HR or non-HR genes, including TP53, PTEN, ATM, CHEK2, PALB2, RAD51C, and STK11. In somatic mutation analysis, TP53 showed frequent pathogenic or likely pathogenic mutations in 56.5% (35/62) of enrolled cases, among which six cases harbored a loss of heterozygosity.

Conclusions

This is the first report of multi-gene panel testing for germline and somatic mutations among Chinese EOC patients, which revealed a broader deleterious variants than only BRCA testing.

Registration

Registration No. NCT03015376, clinicaltrials.gov, registered on January 10, 2017.

Electronic supplementary material

The online version of this article (10.1186/s13048-019-0560-y) contains supplementary material, which is available to authorized users.

BRCA mutation frequency and clinical features of ovarian cancer patients: A report from a Chinese study group

AIM

Subjects with germline BRCA1/2 mutations (gBRCAm) have an increased risk of developing breast cancer and ovarian cancer. At present, knowledge of BRCA1/2 mutation frequency in Chinese patients with ovarian cancer is still insufficient, and the detailed clinical information of these patients is poorly understood.

METHODS

A total of 547 unselected ovarian cancer patients were enrolled, and their gBRCAm status was detected. Clinical characteristics including age, personal and family history, histopathologic diagnosis, carbohydrate antigen 125 (CA-125) level, ascites, Federation International of Gynecology and Obstetrics (FIGO) stage, residual lesions, platinum sensitivity, recurrence interval and survival information were collected. Accurate assessments of disease response were based on the RECIST standard or CA-125 level.

RESULTS

In 547 patients with ovarian cancer, we detected 129 (23.6%) patients with pathogenic mutations, 84 patients with BRCA1 mutations (15.4%) and 45 patients with BRCA2 mutations (8.2%). Twenty-five novel mutations were identified, and the mutation of BRCA1, c.5470_5477del8, was the most common mutation in this study. BRCA1/2 mutations were significantly associated with age; personal and family history; FIGO stage; secondary recurrence interval; sensitivity to platinum in 1st, 2nd and 3rd line treatment; and response to doxorubicin liposomes. Patients with BRCA1/2 mutations showed significant advantages in 3- and 5-year survival rates but no advantage in long-term survival.

CONCLUSION

BRCA1/2 mutation prevalence in Chinese ovarian cancer patients is higher than the international rate. We recommend BRCA1/2 testing for patients with family histories and personal histories of malignancy and genetic counseling for cancer in healthy people with high-risk family histories.