ACKR1 Alleles at 5.6 kb in a Well-Characterized Renewable US Food and Drug Administration (FDA) Reference Panel for Standardization of Blood Group Genotyping

The glycoprotein encoded by the ACKR1 gene expresses the Duffy blood group antigens and is a receptor for malaria parasites. We recently described 18 long-range ACKR1 alleles in an autochthonous population of a malaria endemic region. Extending this work, we sequenced the gene in a 53-sample repository established by the US Food and Drug Administration (FDA) as reference reagents for blood group genotyping. The FDA samples have been characterized for 19 genes; however, long-range haplotype information for these genes, including ACKR1, was lacking. We used a hybrid approach, novel for this type of gene, to characterize ACKR1 by combining two next-generation sequencing technologies, the short-read massively parallel sequencing and the long-read nanopore sequencing. The expedient integration of data from both next-generation sequencing systems were necessary and sufficient to allow determination of all 25 long-range ACKR1 alleles found in the 53 samples accurately. All 25 alleles identified in our current FDA cohort were novel and, unexpectedly, none had been observed among the 18 alleles in our previous study. The alleles will be useful for validation, calibration, and proficiency testing of red cell genotyping. The lack of any overlap between the ACKR1 alleles in the two studies documents differences in mutation rate and recombination frequency among populations. The exact haplotype and their interethnic or interpopulation dissimilarities can influence disease susceptibility and therapy.

Analysis of the StoRM cohort reveals physical activity to be associated with survival in metastatic breast cancer

Benefits of physical activity are widely demonstrated for early stage cancers but few studies have focused on metastatic disease. The purpose of this study was to determine the impact of physical activity on survival in patients with metastatic breast cancer. We conducted a secondary analysis of the national, multicentric, non-randomized, prospective cohort SNPs to Risk of Metastasis (StoRM) study. The level of physical activity was self-reported at inclusion and divided into three categories of physical activity: light level, moderate level, and vigorous level. Overall, 833 patients (56.2%) completed the physical activity questionnaire at baseline on average physical activity during the previous year: 11.6% had a light level of physical activity, 69.0% achieved moderate levels of physical activity and 19.3% reported vigorous levels of physical activity. After adjustment for confounding, physical activity was not statistically significantly associated with overall survival in the whole population. Subgroup analysis identified that both vigorous and moderate physical activity were associated with statistically significantly improved overall survival compared to light physical activity level only in the HER2 positive subgroup (HR 0.23; 95% CI 0.07-0.70, p = 0.01 and HR 0.38; 95% CI 0.15-0.96, p = 0.04). Physical activity done during the previous year was associated with survival in HER2 positive metastatic breast cancer patients. These results suggest that overall survival in metastatic breast cancer patients could be improved through physical activity which should be considered as a complementary intervention for these individuals. The study showed that moderate/vigorous levels of physical activity were associated with better overall survival, and that these associations remained statistically significant in multivariate analysis in the HER2 positive subgroup. These results have clinical relevance and justify the recommendations for physical activity interventions in metastatic breast cancer.

Genomic and Phylogenetic Analysis of Zika Virus Isolates from Asymptomatic Blood Donors in the United States and Puerto Rico, 2016

Zika virus (ZIKV) caused a public health threat in the United States in 2016, leading to rapid development and implementation of blood screening assays for ZIKV RNA. Several ZIKV sequences from clinical cases have been reported, but none from asymptomatic/pre-symptomatic infections. We isolated and sequenced ZIKV from asymptomatic/pre-symptomatic blood donor (ABD-ZIKV) samples and compared with reported clinical sequences. Twelve ABD-ZIKV isolates were produced from 67 cultivated samples, and isolates were genetically similar among themselves. Most isolates shared mutations with the clinical isolate PRVABC59 2015, whereas two ABD-ZIKV isolates shared specific mutations with U.S. clinical isolates from 2016. The ABD-ZIKV strains clustered into two distinct subclades: one comprised mostly ABD-ZIKV from Puerto Rico, and another one comprised ABD-ZIKV from Florida and QTX-02 isolate (Puerto Rico). In this study, we showed the circulation of two slightly distinct virus strains among Puerto Rico blood donors, one of which was also reported in Florida.

A phase II of gemcitabine combined with pazopanib followed by pazopanib maintenance, as second-line treatment in patients with advanced leiomyosarcomas: A unicancer French Sarcoma Group study (LMS03 study)

BACKGROUND

Options in second-line therapy after doxorubicin-based chemotherapy for metastatic/advanced leiomyosarcoma include gemcitabine (G), trabectedin and pazopanib (P) monotherapy. Currently, no combination therapy is better than monotherapy. LMS03 is an open-label multicentre single-group phase II study designed to assess the efficacy and tolerance of G + P in the second-line setting.

PATIENTS AND METHODS

Patients (pts), ECOG ≤2, with metastatic leiomyosarcomas (LMS) after first-line doxorubicin chemotherapy failure were eligible. Pts were treated with G 1000 mg/m² on days 1 and 8 of each 21 days (maximum eight cycles), in combination with oral daily P (800 mg), until disease progression/toxicity. 9-month progression-free survival (PFS) rate was the primary endpoint. Inacceptable and promising 9-month PFS rates were defined, in the intent-to-treat population, as 32% and 44%.

RESULTS

106 pts were included with a mean age of 59.8 years and an ECOG 0 in 63.5%; the primary tumour site was uterus in 61%. Pts were treated with P + G for a median of 3.8 mo, and P for a median of 4.2 mo. The 9-month PFS rate was 32.1% (95% CI 23.1-41.1). After a median follow-up of 14.2 months, the PFS was 6.5 months (95% CI 5.6-8.2), and the overall survival was 22.4 months (95% CI 16.9-26.5). The best response was 23.8%. The most frequent reported grade 3-4 adverse events were haematological.

CONCLUSIONS

LMS03 failed to show that second-line therapy, with gemcitabine combined with pazopanib, followed by pazopanib alone, was beneficial for advanced LMS patients. Eudract N°2011-001308-36 and NCT01442662.

Use of Monocyte-Derived Macrophage Culture Increases Zika Virus Isolation Rate from Human Plasma

Viral isolation is desirable for many reasons, including development of diagnostic assays and reference materials, and for virology basic research. Zika virus (ZIKV) isolation from clinical samples is challenging, but isolates are known to infect various cell lines. Here, we evaluated suitability of Vero, C6/36 and JEG-3 as host cells, for direct isolation of ZIKV from human plasma. We also assessed the use of primary monocyte-derived macrophages (MDMs) culture to enhance ZIKV isolation from human plasma samples followed by virus expansion in Vero, C6/36 and JEG-3 cultures. Direct inoculation of cell lines with 42 ZIKV-RNA positive samples resulted in isolation rates of 9.52% (4/42) in Vero and C6/36, and of 7.14% (3/42) in JEG-3 cells. Inoculation of plasma in MDMs followed by supernatant testing by TaqMan RT-PCR, resulted in 33/42 (78.57%) ZIKV-RNA-positive supernatants, which expansion in cell lines increased isolation rates to 24.24% (8/33) in Vero and to 27.27% (9/33) in C6/36 and JEG-3 regardless of the presence of ZIKV-antibody. Isolates generated in JEG-3 cells were also produced in Vero and C6/36 with similar viral titers. These results suggest that efficiency of ZIKV isolation from human plasma can be enhanced when MDM culture is used before viral expansion in cell lines.

Community engagement in public health emergency preparedness

Background

Communities that could be affected by infectious disease outbreaks are increasingly recognised as resources that may be effectively utilized by the authorities during public health emergencies.

Methods

This case study project, aiming to identify synergies between communities and authorities, was based on qualitative sources of evidence, including document and media review, stakeholder mapping, interviews and FGDs (N = 137). Four countries were selected for inclusion: Spain and the Netherlands on the basis of emerging tick-born disease incidents; Iceland and Ireland on the basis of acute gastroenteritis outbreaks.

Results

In the Netherlands and Spain strong synergies were identified in tick surveillance activities, and the value of pre-existing networks of interest groups for preparedness and response activities was recognised. The Icelandic norovirus event was unexpected and fast-moving, while VTEC in Ireland is a familiar and slower-burning challenge. As a relatively common disease in Ireland, VTEC-protocols are closely followed, while a generic all-hazards approach was taken in Iceland. There was considerable community support in the responses in both countries., and in Iceland community representatives also actively participated in producing institutional post-event evaluations.

Conclusions

An over-riding principle emerging from this study is that an informed, at-risk community understands the challenges to adopting effective preventive practices for themselves better than anyone. Additional good practices included the utilisation of pre-existing stakeholder networks for information dissemination; and of monitoring community perceptions of any public health incident, including through social media, in order to identify and manage misperceptions. Efforts to build on the community engagement activities that are already in place in the four countries could contribute to better preparedness planning and more efficient and timely responses in future outbreaks.

Key messages

Recognise the community as a real partner in outbreak preparedness, response, and recovery. Optimise communications with communities who may be affected by outbreaks.

UCBG 2-04: Long-term results of the PACS 04 trial evaluating adjuvant epirubicin plus docetaxel in node-positive breast cancer and trastuzumab in the human epidermal growth factor receptor 2-positive subgroup

PURPOSE

We conducted a double-randomised phase III trial to evaluate a concomitant taxane-anthracycline regimen in node-positive breast cancer and the efficacy of trastuzumab in the human epidermal growth factor receptor 2 (HER2)-positive subpopulation.

METHODS

A total of 3010 patients with node-positive breast cancer were randomly assigned to receive 6 cycles of 500 mg/m² of fluorouracil, 100 mg/m² of epirubicin and 500 mg/m² of cyclophosphamide (FEC) or 75 mg/m² of epirubicin and 75 mg/m² of docetaxel (ED). Patients with HER2-positive tumours were secondary randomly assigned to either trastuzumab or observation. The primary end-point was disease-free survival (DFS) in the two chemotherapy arms.

RESULTS

After a 115-month median follow-up, DFS was not significantly better in the ED arm (DFS: 70%, 95% confidence interval [CI]: 67-72) than in the FEC arm (DFS: 68%, 95% CI: 65-70; hazard ratio [HR] = 0.88, 95% CI: 0.77-1.01; p = 0.064). The OS was not different between FEC (OS: 80%, 95% CI: 78-83) and ED (OS: 81%, 95% CI: 79-83); HR = 0.97, 95% CI: 0.81-1.16; p = 0.729). ED appeared more toxic. In the 528 HER2-positive subset, there was trend for a higher DFS, in the intention-to-treat population, in the trastuzumab arm (DFS: 68%, 95% CI: 61-74) than in the observation arm (DFS: 60%, 95% CI: 54-66; HR = 0.77, 95% CI: 0.57-1.03; p = 0.079). In the per-protocol population, DFS was significantly higher in the trastuzumab arm (DFS: 70%, 95% CI: 63-76) than in the observation arm (DFS: 59%, 95% CI: 53-65; HR = 0.69, 95% CI: 0.51-0.94; p = 0.0156). The OS was not different between these 2 arms.

CONCLUSION

This study did not show superiority of the concomitant anthracycline-taxane arm which was more toxic in high-risk node-positive breast cancer patients. Long-term results of the HER2-positive subpopulation are in line with those of the other adjuvant trastuzumab trials but quantitatively less pronounced mostly because of lack of power.

A Zika Reference Panel for Molecular-Based Diagnostic Devices as a US Food and Drug Administration Response Tool to a Public Health Emergency

In 2015, Zika virus (ZIKV) appeared as an emerging pathogen, generating a global and urgent need for accurate diagnostic devices. During this public health crisis, several nucleic acid testing (NAT)-based Zika assays were submitted to the US Food and Drug Administration (FDA) for Emergency Use Authorization. The FDA's Center for Devices and Radiological Health, in collaboration with the FDA's Center for Biologics Evaluation and Research, responded to this Zika emergency by developing and producing a reference panel (RP) for Zika RNA (Zika FDA-RP) suitable for performance assessment of ZIKV NAT-based in vitro diagnostic devices. Reference panels are a fundamental tool for performance assessment of molecular tests. The panel is composed of five vials: two different heat-inactivated ZIKV strains (PRVABC59 and FSS13025) in concentrated stocks and three blinded concentrations prepared from those strains. The Zika FDA-RP was shared with developers who had devices in the final stages of validation. In vitro diagnostic developers tested the Zika FDA-RP using the FDA-provided protocol. Depending on sample type, 85% (12/14) of the NAT assays had analytical sensitivities between 500 and 5000 RNA NAT-detectable units/mL (NDUs/mL). One device showed better performance (100 NDUs/mL), and another one showed lower performance (10,000 to 30,000 NDUs/mL). Vials of the Zika FDA-RP are available on request to developers who have interacted with the FDA through the review process.

Evidence-based MR imaging follow-up strategy for desmoid-type fibromatosis

OBJECTIVES

To propose a follow-up strategy for desmoid-type fibromatosis (DF) based on tumor growth behavior and the signal on T2-weighted MRI.

METHODS

We retrospectively reviewed 296 MRI studies of 34 patients with histologically proven DF. In each study, tumor volume and T2 signal relatively normal striated muscle were assessed. Volume variation and monthly growth rates were analyzed to determine lesion growth behavior (progressing versus stable/regressing lesions). Growth behavior was correlated with T2 signal, tumor location, β-catenin status, treatment strategy, and follow-up duration. Interobserver variability of volume measurements and interobserver measurement variation ratio were assessed.

RESULTS

There were 25 women and 9 men with a mean age of 39.9 ± 19 (4-73) years. Mean follow-up time in the patients included was 55 ± 41 (12-148) months. In progressing lesions, the mean average monthly growth ratio was 10.9 ± 9.2 (1.1-42.5) %. Interobserver variability of volume measurements was excellent (ICC = 0.96). Mean interobserver measurement variation ratio was 20.4 ± 23.6%. The only factor correlated with tumor growth behavior was T2 signal ratio (p < 0.0001). Seventeen out of 34 (50%) patients presented a signal change over the threshold of 1 during follow-up. There were five occurrences of secondary growth after a period of stability with a mean delay until growth of 38.2 ± 44.2 (17-116) months.

CONCLUSION

DF growth rate was quantitatively assessed. A threshold for volume variation detection was established. DF growth behavior was significantly related to T2 signal. An evidence-based follow-up strategy is proposed.

KEY POINTS

• In progressing desmoid fibromatosis, the mean average monthly growth ratio was 10.9 ± 9.2%. • Lesions with muscle/tumor T2 signal ratios lower than 1 tended to be stable or regress over time. • Given the interobserver measurement variability and MRI in-plane spatial resolution, a variation higher than 42.6% in tumor volume is required to confirm punctual progression.

Results of API-AI based regimen in osteosarcoma adult patients included in the French OS2006/Sarcome-09 study

In the OS2006 study, patients younger than 18 years were treated with a methotrexate-based regimen (MTX), patients older than 25 years with a doxorubicin-cisplatin-ifosfamide-based regimen (API-AI), whereas patients aged 18-25 years received either API-AI or MTX. We herein report the prespecified subgroup analysis of the outcome of 106 patients treated with API-AI. Preoperative chemotherapy combined three doxorubicin-ifosfamide-cisplatin (API) and two doxorubicin-ifosfamide (AI) courses. Postoperative chemotherapy was assigned by risk group: localised patients with a good histological response (<10% viable cells) received two AI and two cisplatin-ifosfamide (PI) courses; patients with synchronous metastases, poor histological response or unresectable primary received five cycles of etoposide-ifosfamide (EI). Of the 106 patients, 61 were randomised to receive or not zoledronate. Median age was 30 years (range 18-67), 66 (62%) patients were >25 years. The primary tumours were axial in 28 patients (26%), and 28 (26%) presented with metastases. Ninety-six patients (91%) had surgery, conservative in 82 (85%); 36 patients (38%, 95% CI 28-48%) were good responders. Toxicity was manageable, with no significant difference in severe acute toxicity between patients aged >25 years and those younger. With a median follow-up of 4.8 years, the 5-year event-free survival and overall survival rates were 46% (95% CI 36-56) and 57% (95% CI 47-67), respectively. The primary tumour size and initial metastases correlated with a higher risk of event. In these 106 osteosarcoma adult patients, API-AI proved feasible with no excess of toxicity, and favourable activity despite poor-prognosis factors.

Surgery in reference centers improves survival of sarcoma patients: a nationwide study

BACKGROUND

NETSARC (netsarc.org) is a network of 26 sarcoma reference centers with specialized multidisciplinary tumor boards (MDTB) aiming to improve the outcome of sarcoma patients. Since 2010, presentation to an MDTB and expert pathological review are mandatory for sarcoma patients nationwide. In the present work, the impact of surgery in a reference center on the survival of sarcoma patients investigated using this national NETSARC registry.

PATIENTS AND METHODS

Patients' characteristics and follow-up are prospectively collected and data monitored. Descriptive, uni- and multivariate analysis of prognostic factors were conducted in the entire series (N = 35 784) and in the subgroup of incident patient population (N = 29 497).

RESULTS

Among the 35 784 patients, 155 different histological subtypes were reported. 4310 (11.6%) patients were metastatic at diagnosis. Previous cancer, previous radiotherapy, neurofibromatosis type 1 (NF1), and Li-Fraumeni syndrome were reported in 12.5%, 3.6%, 0.7%, and 0.1% of patients respectively. Among the 29 497 incident patients, 25 851 (87.6%) patients had surgical removal of the sarcoma, including 9949 (33.7%) operated in a NETSARC center. Location, grade, age, size, depth, histotypes, gender, NF1, and surgery outside a NETSARC center all correlated to overall survival (OS), local relapse free survival (LRFS), and event-free survival (EFS) in the incident patient population. NF1 history was one of the strongest adverse prognostic factors for LRFS, EFS, and OS. Presentation to an MDTB was associated with an improved LRFS and EFS, but was an adverse prognostic factor for OS if surgery was not carried out in a reference center. In multivariate analysis, surgery in a NETSARC center was positively correlated with LRFS, EFS, and OS [P < 0.001 for all, with a hazard ratio of 0.681 (95% CI 0.618-0.749) for OS].

CONCLUSION

This nationwide registry of sarcoma patients shows that surgical treatment in a reference center reduces the risk of relapse and death.

6 months versus 12 months of adjuvant trastuzumab in early breast cancer (PHARE): final analysis of a multicentre, open-label, phase 3 randomised trial

BACKGROUND

In 2013, the interim analysis of the Protocol for Herceptin as Adjuvant therapy with Reduced Exposure (PHARE) trial could not show that 6 months of adjuvant trastuzumab was non-inferior to 12 months. Here, we report the planned final analysis based on the prespecified number of occurring events.

METHODS

PHARE is an open-label, phase 3, non-inferiority randomised trial of patients with HER2-positive early breast cancer comparing 6 months versus 12 months of trastuzumab treatment concomitant with or following standard neoadjuvant or adjuvant chemotherapy. The study was undertaken in 156 centres in France. Eligible patients were women aged 18 years or older with non-metastatic, operable, histologically confirmed adenocarcinoma of the breast and either positive axillary nodes or negative axillary nodes but a tumour of at least 10 mm. Participants must have received at least four cycles of a chemotherapy for this breast cancer and have started receiving adjuvant trastuzumab-treatment. Eligible patients were randomly assigned to either 6 months or 12 months of trastuzumab therapy duration between the third and sixth months of adjuvant trastuzumab. The randomisation was stratified by concomitant or sequential treatment with chemotherapy, oestrogen receptor status, and centre. The primary objective was non-inferiority in the intention-to-treat population in the 6-month group in terms of disease-free survival with a prespecified hazard margin of 1·15. This trial is registered with ClinicalTrials.gov, number NCT00381901.

FINDINGS

3384 patients were enrolled and randomly assigned to either 12 months (n=1691) or 6 months (n=1693) of adjuvant trastuzumab. One patient in the 12-month group and three patients in the 6-month group were excluded, so 1690 patients in each group were included in the intention-to-treat analysis. At a median follow-up of 7·5 years (IQR 5·3-8·8), 704 events relevant to disease-free survival were observed (345 [20·4%] in the 12-month group and 359 [21·2%] in the 6-month group). The adjusted hazard ratio for disease-free survival in the 12-month group versus the 6-month group was 1·08 (95% CI 0·93-1·25; p=0·39). The non-inferiority margin was included in the 95% CI. No differences in effects pertaining to trastuzumab duration were found in any of the subgroups. After the completion of trastuzumab treatment, rare adverse events occurred over time and the safety analysis remained similar to the previously published report. In particular, we found no change in the cardiac safety comparison, and only three additional cases in which the left ventricular ejection fraction decreased to less than 50% have been reported in the 12-month group.

INTERPRETATION

The PHARE study did not show the non-inferiority of 6 months versus 12 months of adjuvant trastuzumab. Hence, adjuvant trastuzumab standard duration should remain 12 months.

FUNDING

The French National Cancer Institute.

Prognosis value of a genetic score based on germline genetic variants in a prospective cohort of early triple-negative breast cancer patients

1529

Background: Triple-negative breast cancers (TNBC) are a heterogeneous group of tumors with poor outcome. In this study, the association between germline genetic variants and invasive disease-free survival (iDFS) was analyzed in TNBC patients. Methods: A genome wide-association study (GWAS) aimed to identify variants (single nucleotide polymorphisms – SNPs) associated with prognosis in 1121 patients with TNBC in the SIGNAL prospective cohort. Associations between gene variants and iDFS were assessed in univariate Cox regression models. Variants were combined in a score to identify risk categories. A prognostic model based on breast cancer stage and genetic variants was estimated using a multivariate Cox regression. Interaction between stage and genetic score was tested. Discrimination of the model was assessed by the Harrell’s C statistic and internal validity by bootstrap method. Results: The characteristics of the 1121 patients were representative of a population with early TNBC. Four SNPs on chromosomes 9 and 2 were found significantly associated to iDFS in univariate Cox models. Homozygous status for the most frequent allele was associated with poorer iDFS for two SNPs and this status was present in 50% and 57% of the population. For the two other SNPs, the most frequent allele was associated with more favorable iDFS. Three prognostic categories were derived from the genetic score. The following table presents the results from the multivariate Cox model including genetic score and disease stage. Clinical trial information: RECF1098. Conclusions: In a prospective cohort of 1121 patients with early TNBC, 4 genetic variants (SNPs) were associated with iDFS. A score involving SNPs provided similar prognostic indications as breast cancer stages. A search assessing the function and the role of the involved genes is ongoing.[Table: see text]

Sarcomas in patients over 90: Natural history and treatment-A nationwide study over 6 years

Soft tissue sarcomas (STS) are rare tumors accounting for less than 1% of human cancers. While the highest incidence of sarcomas is observed in elderly, this population is often excluded or poorly represented in clinical trials. The present study reports on clinicopathological presentation, and outcome of sarcoma patients over 90 recorded in the Netsarc.org French national database. NETSARC (netsarc.org) is a network of 26 reference sarcoma centers with specialized multidisciplinary tumor board (MDTB), funded by the French National Cancer Institute to improve the outcome of sarcoma patients. Since 2010, presentation to an MDTB, second pathological review, and collection of sarcoma patient characteristics and follow‐up are collected in a database Information of patients registered from January 1, 2010, to December 31, 2016, in NETSARC were collected, analyzed and compared to the younger population. Patients with sarcomas aged >90 have almost exclusively sarcomas with complex genomics (92.0% vs. 66.3%), are less frequently metastatic (5.3% vs. 14·7%) at diagnosis, have more often superficial tumors (39.8% vs. 14.7%), as well as limbs and head and neck sites (75.2% vs. 38.7%) (all p < 0.001). Optimal diagnostic procedures and surgery were less frequently performed in patients over 90 (p < 0.001). These patients were less frequently operated in NETSARC centers, as compared to those of younger age groups including aged 80–90. However, local relapse‐free survival, metastatic relapse‐free survival and relapse‐free survival were not significantly different from those of younger patients, in the whole cohort, as well as in the subgroup of operated patients. As expected overall survival was worse in patients over 90 (p < 0.001). Patients over 90 who were not operated had worse overall survival than younger patients (9.9 vs. 27.3 months, p < 0.001). Patients with STS diagnosed after 90 have distinct clinicopathological features, but comparable relapse‐free survival, unless clinical practice guidelines recommendations are not applied. Standard management should be proposed to these patients if oncogeriatric status allows.

What's new?

While the highest incidence of soft‐tissue sarcoma (STS) is observed in the elderly, this population is often excluded or poorly represented in clinical trials. Therefore, little is known about the characteristics, treatment, and outcomes of STS in these patients. In this study, the authors analyzed numerous clinical characteristics of patients with sarcoma diagnosed at age 91 or older. They conclude that standard STS management and clinical practice guidelines should be followed for these patients if possible.

Validated Reference Panel from Renewable Source of Genomic DNA Available for Standardization of Blood Group Genotyping

Extended blood group genotyping is an invaluable tool used for prevention of alloimmunization. Genotyping is particularly suitable when antigens are weak, specific antisera are unavailable, or accurate phenotyping is problematic because of a disease state or recent transfusions. In addition, genotyping facilitates establishment of mass-scale patient-matched donor databases. However, standardization of genotyping technologies has been hindered by the lack of reference panels. A well-characterized renewable reference panel for standardization of blood group genotyping was developed. The panel consists of genomic DNA lyophilized and stored in glass vials. Genomic DNA was extracted in bulk from immortalized lymphoblastoid cell lines, generated by Epstein-Barr virus transformation of peripheral blood lymphocytes harvested from volunteer blood donors. The panel was validated by an international collaborative study involving 28 laboratories that tested each DNA panel member for 41 polymorphisms associated with 17 blood group systems. Overall, analysis of genotyping results showed >98% agreement with the expected outcomes, demonstrating suitability of the material for use as reference. Highest levels of discordance were observed for the genes CR1, CD55, BSG, and RHD. Although limited, observed inconsistencies and procedural limitations reinforce the importance of reference reagents to standardize and harmonize results. Results of stability and accelerated degradation studies support the suitability of this panel for use as reference reagent for blood group genotyping assay development and standardization.

Abstract OT1-03-02: CICLADES: Monitoring of ESR1, PIK3CA and AKT1 ctDNA mutations during real-life follow-up of patients with advanced breast cancer treated with endocrine therapy

Activating ESR1 mutations have recently been reported as a key mechanism leading to Aromatase Inhibitor (AI) resistance. ESR1 mutations occur rarely in primary breast cancers. However, in large retrospective studies, ESR1 mutations occurred in up to 39% of Estrogen-Receptor(ER)-positive metastatic breast cancer resistant to AI. Numerous hotspot mutations have been identified, most of them affecting the ligand-binding domain (LBD) and leading to ligand-independent activation of the ER and to resistance to AI.

Phosphatidylinositol 3-kinase (PI3K)/AKT pathway is involved in key Cellular Mechanisms and mutations in PIK3CA and AKT1 are frequently reported in breast cancer.

In this study, we propose to use a capture-based Next Generation Sequencing (NGS) assay and to use the barcoding and polishing features in our analysis pipeline. This assay will be able to detect all mutations on AKT1, PIK3CA, ESR1 and other genes on circulating tumor DNA (ctDNA) extracted from blood samples of patients with breast cancer. We consider that this exon-screening strategy is relevant according to the recent knowledge.

We plan to prospectively include women with advanced breast cancer about to begin standard-of-care first line endocrine therapy (ET). Patients will be required to have histologically confirmed ER-positive, HER2-negative breast cancer and documented loco-regionally advanced or metastatic disease, not amenable to surgery or radiation with curative intent. Patients with endocrine sensitive disease (no prior ET or relapse more than 12 months after completing adjuvant ET) as well as patients with endocrine resistant disease (relapse while on adjuvant ET or within 12 months of completing adjuvant ET) will be enrolled.

ET can be prescribed alone or in combination with a targeted therapy. Nevertheless, we will recruit at least 25% of patients with exclusive ET in the endocrine sensitive group.

Peripheral-blood samples, for analysis of ctDNA, will be obtained from participating patients at pre-specified time points: at start of ET to determine the baseline mutational status of ESR1, PIK3CA, AKT1 and other genes included in a panel of genes of interest in solid tumors, and then, at evaluation of response to therapy until disease progression or end of study.

Patients will be followed for 36 months or until disease progression. Determination of progression will be done per local investigator.

The primary objective is to describe the prevalence of activating ESR1 mutations affecting the LBD, using NGS, from the start of ET to progression or end of study. Secondary objectives include to describe the prevalence of ESR1 mutations affecting other domains, the prevalence of ESR1 mutations in patients with and without endocrine resistance at enrolment and the prevalence of PIK3CA and AKT1 mutations, to demonstrate that ESR1, PIK3CA and AKT1 mutations whatever their times of onset are predictors of progression free survival.

As of June 2018, 8 sites were opened to recruitment and 18 pts were included; the target enrollment is 146. The trial is supported by AstraZeneca.

Citation Format: Massard V, Uwer L, Salleron J, Deblock M, Kieffer A, Rios M, Gilson P, Lesur A, Harle A, Merlin JL. CICLADES: Monitoring of ESR1, PIK3CA and AKT1 ctDNA mutations during real-life follow-up of patients with advanced breast cancer treated with endocrine therapy [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT1-03-02.

EPIGIST: An observational real-life study on patients with metastatic gastrointestinal stromal tumors receiving imatinib

Background

Gastrointestinal stromal tumors (GISTs) are rare, but represent the most common mesenchymal neoplasms of the gastrointestinal tract. EPIdemiology GIST, is an observational multicenter longitudinal follow-up cohort study reporting the prescribing patterns of imatinib in patients with GIST and the impact of the treatment in a real-world (standard clinical) setting.

Methods

Eligible patients had a confirmed diagnosis of unresectable or metastatic KIT-positive GIST and started treatment with imatinib for the first time between May 24, 2002, and June 30, 2010. During routine visits, annual collection of clinical characteristics was requested, i.e., age, GIST stage at diagnosis, history, imatinib treatment duration and dosage, adherence, and concomitant medications. Survival outcomes were estimated using the Kaplan-Meier method. Other data were analyzed using descriptive statistics.

Results

Of 151 patients enrolled, imatinib was initiated for 126 patients before enrollment and for 25 patients on the day of enrollment or soon after. The patient characteristics were similar to those in published prospective trials. The estimated 1-, 2-, 3-, and 4-year overall survival rates were 90.4% (95% confidence interval [CI; 84.8%-94.0%]), 84.7% (95% CI [78.1%-89.4%]), 73.0% (95% CI [65.0%-79.4%]), and 60.7% (95% CI [51.4%-68.8%]), respectively. The most common adverse events (AEs) were diarrhea (39%), asthenia (39%), eyelid or periorbital edema (32%), abdominal pain (23%), and anemia (21%). Eight of 126 serious AEs were possibly related to the treatment as assessed by investigators.

Conclusions

Study results showed that patients in real-life populations are generally treated in accordance with national and international clinical recommendations and have outcomes comparable to those of patients in clinical trials.