Abstract P5-09-12: Germline mutation in TP53 gene in a cohort of 2,561 Chinese high-risk breast cancer patients using multigene panel testing

Background: Li-Fraumeni syndrome (LFS) is a rare autosomal genetic disorder with germline TP53 mutations. Patients with TP53 mutations have a higher risk of developing breast cancer than those harboring BRCA mutations. Although limited studies have shown that TP53 mutation carriers are less responsive to low dose radiation and more susceptible to induce new malignancies from radiotherapy. Moreover screening strategies allows early detection of a spectrum of cancers related to TP53 mutations. From work of BRCA mutations where over 40% novel mutations were detected in Chinese cohort, it is important to evaluate the frequency of TP53 mutation in Chinese to better understand the spectrum to guide appropriate clinical management of these high risk individuals.

Methods: TP53 gene mutation screening was performed on 2,561 high-risk breast cancer patients using multigene panel testing. The patients were accrued by Hong Kong Hereditary and High Risk Breast Cancer Program from March 2007 to May 2018. All detected pathogenic mutations were further validated by bi-directional DNA sequencing and analyzed by our in-house developed bioinformatics pipeline.

Results: Sixteen distinct pathogenic or likely pathogenic variants were identified, and 3 of them were de novo TP53 mutations (18.75%). The mean age of patients who harbored TP53 mutation was 30.44 years (range 18-44), and 50% of the tumors were bilateral breast cancer. Of sixteen different pathogenic mutations, majority of them were missense mutation (87.5%), and 2 were nonsense mutation (12.5%). Four of the sixteen TP53 mutation carriers had family history of breast cancer, while others had a family history of lung cancer (43.75%).

Conclusion: This study revealed that seven patients were found to habor TP53 mutation even when they did not meet the criteria of LFS of LFS-like phenotype, implicated the importance of using multigene panel test for probands and their relatives to offer a comprehensive surveillance programe for TP53 carriers.

Citation Format: Kwong A, Shin V, Au CH, Ho C, Slavin T, Weitzel J, Chan TL, Ma E. Germline mutation in TP53 gene in a cohort of 2,561 Chinese high-risk breast cancer patients using multigene panel testing [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 P5-09-12.

Open Transcervical Fracture of Femur Resulted from Gunshot Injury: A Case Report

Gunshot injury (GSI) is rare in Hong Kong, and local experience on the management of GSIs is limited. There is yet a worldwide consensus on the classification system or management guidelines for the management of GSIs. We report a case of open transcervical fracture of right femur resulting from a GSI. The management of GSIs, including the classification of these injuries, corresponding fracture and soft tissue management, the indications of bullet removal and antibiotics use will be discussed.

EU/US/CTAD Task Force: Lessons Learned from Recent and Current Alzheimer's Prevention Trials

At a meeting of the EU/US/Clinical Trials in Alzheimer's Disease (CTAD) Task Force in December 2016, an international group of investigators from industry, academia, and regulatory agencies reviewed lessons learned from ongoing and planned prevention trials, which will help guide future clinical trials of AD treatments, particularly in the pre-clinical space. The Task Force discussed challenges that need to be addressed across all aspects of clinical trials, calling for innovation in recruitment and retention, infrastructure development, and the selection of outcome measures. While cognitive change provides a marker of disease progression across the disease continuum, there remains a need to identify the optimal assessment tools that provide clinically meaningful endpoints. Patient- and informant-reported assessments of cognition and function may be useful but present additional challenges. Imaging and other biomarkers are also essential to maximize the efficiency of and the information learned from clinical trials.

Canadian Lung Cancer Conference 2018

The 2018 Canadian Lung Cancer Conference (CLCCO) took place 8–9 February in Vancouver, British Columbia. A highly anticipated event, the CLCCO attracts lung cancer professionals from across Canada to review the latest advances in lung cancer research in a multidisciplinary setting. It also brings world-renowned experts to share their knowledge. Some of the highlights this year included an overview of the remarkable advances in immuno-oncology, stereotactic radiotherapy, and navigational tools in bronchoscopy.

Melatonin versus chloral hydrate as the sedating agent in performing electroencephalogram in paediatric patients

Electroencephalography (EEG) is a valuable tool in the diagnosis of epilepsy. The attainment of a high quality EEG requires patient's co-operation which is particularly difficult in children. Chloral hydrate has been used as a sedating agent in EEGs but it has potential serious adverse effects and anti-epileptic activity. Melatonin is used increasingly in different investigations as a safe alternative. Our study is to compare their effectiveness as sedating agents in performing EEGs and the detection rate of abnormal EEGs. This is a retrospective study performed in a regional hospital in Hong Kong. One hundred and ninety two EEG studies were included from December 2010 to July 2014. One hundred and two children were given chloral hydrate (50 mg/Kg) in the first half of the period and 90 children were given melatonin (3 mg for =< 5 years or 6 mg for >= 5 year) in the later half. The two groups are compared with Pearson's Chi-squared test with Yates’ continuity correction. The successful rate in sedation was similar between the two groups while the pick up rate of abnormal EEGs was 52.56% in the melatonin group and 21.57% in the chloral hydrate group (p < 0.05). Subgroup analysis among patients with epilepsy or mental retardation and intellectual disability shared same findings with higher detection rate of abnormal EEGs in the melatonin group. No side effect was documented in the study. Compare with chloral hydrate, melatonin is a safe and effective alternative and probably has less interference with the electrographic activity.

Successful targeting of the NRG1 pathway indicates novel treatment strategy for metastatic cancer

Background

NRG1 fusion-positive lung cancers have emerged as potentially actionable events in lung cancer, but clinical support is currently limited and no evidence of efficacy of this approach in cancers beyond lung has been shown.

Patients and methods

Here, we describe two patients with advanced cancers refractory to standard therapies. Patient 1 had lung adenocarcinoma and patient 2 cholangiocarcinoma. Whole-genome and transcriptome sequencing were carried out for these cases with select findings validated by fluorescence in situ hybridization.

Results

Both tumors were found to be positive for NRG1 gene fusions. In patient 1, an SDC4-NRG1 gene fusion was detected, similar gene fusions having been described in lung cancers previously. In patient 2, a novel ATP1B1-NRG1 gene fusion was detected. Cholangiocarcinoma is not a disease type in which NRG1 fusions had been described previously. Integrative genome analysis was used to assess the potential functional significance of the detected genomic events including the gene fusions, prioritizing therapeutic strategies targeting the HER-family of growth factor receptors. Both patients were treated with the pan HER-family kinase inhibitor afatinib and both displayed significant and durable response to treatment. Upon progression sites of disease were sequenced. The lack of obvious genomic events to describe the disease progression indicated that broad transcriptomic or epigenetic mechanisms could be attributed to the lack of prolonged response to afatinib.

Conclusion

These observations lend further support to the use of pan HER-tyrosine kinase inhibitors for the treatment of NRG1 fusion-positive in both cancers of lung and hepatocellular origin and indicate more broadly that cancers found to be NRG1 fusion-positive may benefit from such a clinical approach regardless of their site of origin.

Clinical trial information

Personalized Oncogenomics (POG) Program of British Columbia: Utilization of Genomic Analysis to Better Understand Tumour Heterogeneity and Evolution (NCT02155621).

Project HELP: a study protocol to pilot test a shared decision-making tool about treatment options for patients with hepatitis C and chronic kidney disease

BACKGROUND

Recent advances in treatment have given patients with chronic kidney disease (CKD) access to safer and more effective medications to treat comorbid hepatitis C virus (HCV) infection. Given the variety and complexity of treatment options that depend on patients' clinical characteristics and personal preferences, education and decision support are needed to prepare patients better to discuss treatment options with their clinicians.

METHODS

Drawing on International Patient Decision Aids Standards guidelines, literature reviews, and guidance from a diverse expert advisory group of nephrologists, hepatologists, and patients, we will develop and test a HCV and CKD decision support tool. Named Project HELP (Helping Empower Liver and kidney Patients), this tool will support patients with HCV and CKD during decisions about whether, when, and how to treat each illness. The tool will (1) explain information using plain language and graphics; (2) provide a step-by-step process for thinking about treating HCV and CKD; (3) tailor relevant information to each user by asking about the individual's stage of CKD, stage of fibrosis, prior treatment, and comorbidities; (4) assess user knowledge and values for treatment choices; and (5) help individuals use and consider information appropriate to their values and needs to discuss with a clinician. A pilot study including 70 individuals will evaluate the tool's efficacy, usability, and likelihood of using it in clinical practice. Eligibility criteria will include individuals who understand and read English, who are at least 18 years old, have a diagnosis of HCV (any genotype) and CKD (any stage), and are considering treatment options.

DISCUSSION

This study can identify particular characteristics of individuals or groups that might experience challenges initiating treatment for HCV in the CKD population. This tool could provide a resource to facilitate patient-clinician discussions regarding HCV and CKD treatment options.

Abstract PD3-04: Complete pathologic response rate to neoadjuvant chemotherapy increases with increasing HER2 ratio in HER2 over-expressing breast cancer: Analysis of the National cancer database (NCDB)

Background: HER2-positive (HER2+) breast cancer is an aggressive subtype that overexpresses human epidermal growth factor receptor 2 promoting cancer cell growth. Monoclonal antibodies targeting the HER2 receptor have improved survival for this patient population, and current NCCN guidelines recommend consideration of neoadjuvant anti-HER2 therapy (NAC) in Stage 2 & 3 HER2+ breast cancer. Pathologic complete response (pCR) to NAC has correlated with longer disease free survival in multiple trials.

Per ASCO-CAP guidelines tumors are considered HER2+ if HER2 copy number≥ 6/cell, HER2/CEP17 ratio≥ 2, or ratio&lt;2 & HER2 copy number ≥6/cell. We hypothesize that patients with higher HER2 ratios will have higher rates of pCR after NAC.

Methods: The National Cancer Database is supported by the American College of Surgeons and the American Cancer Society containing de-identified patient treatment data from over 1,500 US facilities. We performed a retrospective review comparing pCR rates after NAC based on HER2 ratio. Patients were excluded if they were HER2 negative, did not undergo NAC, or if the HER2 ratio was not recorded. Chi-squared and Fisher's exact test were used to compare pCR versus partial response between deciles of HER2 ratios.

Results: The NCDB included 237,118 patients with HER2 equivocal or HER2+ breast tumors. 29,291 of these patients underwent NAC, and HER2 ratios were recorded in 14,597 of the NAC cases. The majority (98%) of included cases were from 2010-2014. A pCR was noted in 9,752 patients and 11,402 patients had a partial response. No response was observed in 1,735 patients and 6,402 patients had a response but the degree was not recorded.

HER2 ratios were significantly different between pCR vs. partial response groups, p &lt;0.001. We identified a direct relationship between increasing HER2 ratio and response to NAC. For ratios 2-2.9, 23.6% achieved pCR and 44.7% had a partial response. For ratio of 5-5.9, 40.7% achieved pCR and even higher rates of pCR were noted for ratios 8-8.9; 49.5% achieved pCR. While both estrogen receptor (ER) positive and ER negative tumors demonstrated this trend, ER negative tumors had higher rates of pCR (ER negative pCR range 37.6% to 59.4% vs ER positive pCR range 16.9% to 42.3%, p&lt;0.01).

Conclusion: Contrary to current dogma, not all HER2+ tumors respond similarly to NAC. We demonstrate a linear relationship between HER2 ratio and pCR in over 14,000 patients. Those with HER2 ratios ≥5.0 were more likely to achieve pCR compared to patients with ratio ≤4.9. The NCDB reflects current clinical practice across the country not restricted to confines of clinical trials, and in this population higher HER2 ratios are predictive of pCR after NAC.

Response to NAC by Her2 Ratio- Complete vs Partial Response  Response to NAC   p ValueHER2 Ratio Complete Response- pCR (N) Partial Response (N)   1.00- 1.99141819.5%343047.2%&lt;0.01 2.00- 2.9951423.6%97444.7%&lt;0.01 3.00- 3.9928328.7%41942.4%&lt;0.01 4.00- 4.9926533.2%30638.2%&lt;0.01 5.00- 5.9929940.7%24333.1%&lt;0.01 6.00- 6.9929241.0%25435.5%&lt;0.01 7.00- 7.9924746.2%17432.5%&lt;0.01 8.00- 8.9918749.5%12132.0%&lt;0.01 9.00- 9.87 and greater44143.9%31431.3%&lt;0.01TOTAL 394627.0%623542.7%&lt;0.01

Citation Format: Greenwell K, Hussain L, Ho C, Dunki-Jacobs E, Lee D, Bramlage M, Bills G, Mehta A, Jones J, Jackson A, Wexelman B. Complete pathologic response rate to neoadjuvant chemotherapy increases with increasing HER2 ratio in HER2 over-expressing breast cancer: Analysis of the National cancer database (NCDB) [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr PD3-04.