Development of the NOGGO GIS v1 Assay, a Comprehensive Hybrid-Capture-Based NGS Assay for Therapeutic Stratification of Homologous Repair Deficiency Driven Tumors and Clinical Validation

The worldwide approval of the combination maintenance therapy of olaparib and bevacizumab in advanced high-grade serous ovarian cancer requires complex molecular diagnostic assays that are sufficiently robust for the routine detection of driver mutations in homologous recombination repair (HRR) genes and genomic instability (GI), employing formalin-fixed (FFPE) paraffin-embedded tumor samples without matched normal tissue. We therefore established a DNA-based hybrid capture NGS assay and an associated bioinformatic pipeline that fulfils our institution's specific needs. The assay´s target regions cover the full exonic territory of relevant cancer-related genes and HRR genes and more than 20,000 evenly distributed single nucleotide polymorphism (SNP) loci to allow for the detection of genome-wide allele specific copy number alterations (CNA). To determine GI status, we implemented an %CNA score that is robust across a broad range of tumor cell content (25-85%) often found in routine FFPE samples. The assay was established using high-grade serous ovarian cancer samples for which BRCA1 and BRCA2 mutation status as well as Myriad MyChoice homologous repair deficiency (HRD) status was known. The NOGGO (Northeastern German Society for Gynecologic Oncology) GIS (GI-Score) v1 assay was clinically validated on more than 400 samples of the ENGOT PAOLA-1 clinical trial as part of the European Network for Gynaecological Oncological Trial groups (ENGOT) HRD European Initiative. The "NOGGO GIS v1 assay" performed using highly robust hazard ratios for progression-free survival (PFS) and overall survival (OS), as well a significantly lower dropout rate than the Myriad MyChoice clinical trial assay supporting the clinical utility of the assay. We also provide proof of a modular and scalable routine diagnostic method, that can be flexibly adapted and adjusted to meet future clinical needs, emerging biomarkers, and further tumor entities.

Disseminated Primary Uterine Hepatoid Adenocarcinoma with α-Fetoprotein Production Demonstrated on 18F-FDG PET/CT

We present the 18F-Fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) findings in a 57-year-old woman with post-menopausal bleeding diagnosed with hepatoid adenocarcinoma (HAC) with a primary tumour in the uterine corpus and a highly elevated level of serum-α-fetoprotein (S-AFP) at presentation. HAC is a variant of adenocarcinoma with hepatic differentiation representing a heterogeneous group of neoplasms that morphologically and immunphenotypically resemble hepatocellular carcinoma (HCC) but are of extrahepatic origin. Microscopically, they are usually poorly differentiated adenocarcinomas proliferating in solid sheets or in a trabecular or cord-like arrangement. Primary uterine HAC is exceedingly rare with a general poor prognosis, and data is sparse and limited to case reports, making the clinical management challenging. Various primary anatomical sites have been reported in the literature, with the stomach being the most common primary site. 18F-FDG PET/CT plays an important role in staging and follow-up in many gynecological malignancies including uterine corpus cancer. To the best of our knowledge, this is the first report describing a primary uterine hepatoid adenocarcinoma with metastases to bone, vagina and lymph nodes on 18F-FDG PET/CT. By utilizing the ability of PET to detect early metabolic changes prior to visible structural changes on conventional imaging, this case illustrates a potential role of 18FDG-PET/CT in the staging of primary endometrial HAC by depicting distant metastasis that is not readily identifiable on CT alone.

Progression-free survival (PFS) and second PFS (PFS2) by disease stage in patients (pts) with homologous recombination deficiency (HRD)-positive newly diagnosed advanced ovarian cancer receiving bevacizumab (bev) with olaparib/placebo maintenance in the phase III PAOLA-1/ENGOT-ov25 trial

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Background: In the Phase III PAOLA-1/ENGOT-ov25 trial (NCT02477644), the addition of maintenance olaparib to bev in pts with newly diagnosed advanced high-grade ovarian cancer (HGOC) resulted in a significant PFS benefit, particularly in HRD-positive (HRD+) pts (hazard ratio [HR] 0.33; 95% CI 0.25–0.45) (Ray-Coquard et al. NEJM 2019). We explored efficacy in HRD+ pts by disease stage. Methods: Pts with newly diagnosed, FIGO stage III–IV HGOC in response after platinum-based chemotherapy + bev received bev (15 mg/kg q3w for 15 months [mo]) + either olaparib (300 mg bid for 24 mo) or placebo (pbo). This exploratory analysis evaluated PFS (data cut-off [DCO]: Mar 22 2019) and PFS2 (DCO: Mar 22 2020) in HRD+ pts (tumor BRCA1/ BRCA2 mutation [tBRCAm] or genomic instability score [Myriad myChoice HRD Plus] ≥42) by FIGO stage. Results: 387/806 randomized pts (48%) were HRD+; 272/387 (70%) had stage III disease and 115/387 (30%) had stage IV disease. 153 (56%) HRD+ stage III pts and 61 (53%) HRD+ stage IV pts had a tBRCAm. Among HRD+ stage III pts, 172 (63%) had upfront surgery (51/172 [30%] had residual disease) and 90 (33%) had interval surgery (19/90 [21%] had residual disease); 52 (45%) HRD+ stage IV pts had upfront surgery (34/52 [65%] had residual disease) and 55 (48%) had interval surgery (18/55 [33%] had residual disease). Median follow-up for PFS and PFS2 was respectively 24.8 and 37.2 mo in HRD+ stage III pts and 24.0 and 37.0 mo in HRD+ stage IV pts. Median PFS, PFS2 and HRs are in the Table. Among HRD+ stage III pts, 36-mo PFS2 (olaparib + bev vs pbo + bev) was 74% vs 60%; among HRD+ stage IV pts, 53% vs 30%. Among HRD+ stage III pts with no residual disease after upfront surgery, HR (95% CI) for PFS was 0.15 (0.07–0.30) and for PFS2 was 0.22 (0.06–0.67). Among HRD+ stage III pts with residual disease after upfront surgery or who received neoadjuvant chemotherapy, or HRD+ stage IV pts, HR (95% CI) for PFS was 0.38 (0.27–0.53) and PFS2 was 0.68 (0.46–1.03). Conclusions: In the PAOLA-1 study, maintenance olaparib + bev provided a PFS and PFS2 benefit over pbo + bev in HRD+ pts, irrespective of FIGO stage and residual disease after upfront surgery. Clinical trial information: NCT02477644. [Table: see text]

Maintenance olaparib plus bevacizumab (bev) after platinum-based chemotherapy plus bev in patients (pts) with newly diagnosed advanced high-grade ovarian cancer (HGOC): Efficacy by BRCA1 or BRCA2 mutation in the phase III PAOLA-1 trial

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Background: In PAOLA-1/ENGOT-ov25 (NCT02477644), adding the PARP inhibitor olaparib to maintenance bev after first-line platinum-based chemotherapy plus bev led to a statistically significant progression-free survival (PFS) benefit in pts with advanced HGOC (HR 0.59; 95% CI 0.49–0.72) (Ray-Coquard et al. 2019). Retrospective subgroup analysis in GOG-0218 (Norquist et al. 2018) suggested BRCA mutation (BRCAm) status did not significantly impact the PFS benefit provided by bev. We explored the efficacy of olaparib plus bev by BRCA1 mutation ( BRCA1m) or BRCA2 mutation ( BRCA2m) in PAOLA-1. Methods: PAOLA-1 is a randomized, double-blind, Phase III trial in pts with newly diagnosed, FIGO stage III–IV, high-grade serous or endometrioid OC, fallopian tube or primary peritoneal cancer receiving platinum-based chemotherapy plus bev then maintenance bev. Pts unrestricted by surgical outcome or BRCAm status and in response to first-line therapy were randomized to maintenance olaparib tablets (300 mg bid for up to 24 months) plus bev (15 mg/kg q3w for up to 15 months in total) or placebo plus bev, stratified by first-line treatment outcome and tumor BRCAm status. Investigator-assessed PFS (modified RECIST v1.1) by BRCAm was a predefined analysis. Results: Of 806 randomized pts, 160 (20%) had tumor BRCA1m, 76 (9%) had tumor BRCA2m and 1 (<1%) had both. Median PFS follow-up was 24.1 and 27.4 months in BRCA1m and BRCA2m pts, respectively. At primary data cutoff, PFS was prolonged with olaparib plus bev versus placebo plus bev in BRCA1m pts and BRCA2m pts (Table). The percentage of BRCA1m pts who received olaparib plus bev and were progression-free at 1 and 2 years was 95% and 73% (vs. 70% and 29% for placebo plus bev) and for BRCA2m pts was 89% and 84% (vs. 84% and 53%) (Kaplan-Meier estimates). Conclusions: In PAOLA-1, maintenance olaparib plus bev provided a significant PFS benefit versus placebo plus bev in all pts analysed, regardless of whether they had BRCA1m or BRCA2m. The median PFS in the control arm suggests a role for bev in this subgroup and the hazard ratio versus an active control arm shows the value of adding maintenance olaparib to bev. Clinical trial information: NCT02477644. [Table: see text]