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Background: oestrogen receptor positive/ human epidermal growth factor receptor positive (ER+/HER2+) breast cancers (BCs) are less responsive to endocrine therapy than ER+/HER2- tumours. Mechanisms underpinning the differential behaviour of ER+HER2+ tumours are poorly characterised. Our aim was to identify biomarkers of response to 2 weeks’ presurgical AI treatment in ER+/HER2+ BCs. Methods: all available ER+/HER2+ BC baseline tumours (n=342) in the POETIC trial were gene expression profiled using BC360™ (NanoString) covering intrinsic subtypes and 46 key biological signatures. Early response to AI was assessed by changes in Ki67 expression and residual Ki67 at 2 weeks (Ki67 2wk). Time-To-Recurrence (TTR) was estimated using Kaplan-Meier methods and Cox models adjusted for standard clinicopathological variables. New molecular subgroups (MS) were identified using consensus clustering. Findings: HER2-enriched (HER2-E) subtype BCs (44.7% of the total) showed poorer Ki67 response and higher Ki67 2wk (p2wk. Five new MS that were associated with differential response to AI were identified. HER2-E had significantly poorer TTR compared to Luminal BCs (HR 2.55, 95% CI 1.14–5.69; p=0.0222). The new MS were independent predictors of TTR, adding significant value beyond intrinsic subtypes. Interpretation: our results show HER2-E as a standardised biomarker associated with poor response to AI and worse outcome in ER+/HER2+. HRD, TP53 mutational score and immune-tumour tolerance are predictive biomarkers for poor response to AI. Lastly, novel MS identify additional non-HER2-E tumours not responding to AI with an increased risk of relapse. Funding: Cancer Research UK (CRUK/07/015).

Background Immunotherapy is revolutionising the treatment of patients diagnosed with melanoma and other cancers. The first immune checkpoint inhibitor, ipilimumab (targeting cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4)), showed a survival advantage over standard chemotherapy. Subsequently the anti-programmed cell death protein 1 (PD-1) antibodies, nivolumab and pembrolizumab were shown to be more effective than ipilimumab. Ipilimumab combined with nivolumab gives an incremental gain in overall survival compared with nivolumab alone but increases the risk of severe, potentially life-threatening toxicities. In contrast to ipilimumab monotherapy, anti-PD-1 antibodies are licensed to be continued until disease progression. Follow-up of patients recruited to the first trials evaluating 2 years of pembrolizumab showed that three-quarters of responding patients continue responding after stopping treatment. Suggestive of early response, we hypothesised that continuing anti-PD-1 treatment beyond 1 year in progression-free patients may be unnecessary and so designed the DANTE trial. Methods DANTE is a multicentre, randomised, phase III, non-inferiority trial to evaluate the duration of anti-PD-1 therapy in patients with metastatic (unresectable stage III and stage IV) melanoma. It uses a two-stage recruitment strategy, registering patients before they complete 1 year of first-line anti-PD-1 +/− CTLA-4 therapy and randomising eligible patients who have received 12 months of treatment and are progression-free at 1 year. At randomisation, 1208 patients are assigned (1:1) to either 1) continue anti-PD-1 treatment until disease progression/ unacceptable toxicity/ for at least 2 years in the absence of disease progression/ unacceptable toxicity or 2) to stop treatment. Randomisation stratifies for baseline prognostic factors. The primary outcome is progression-free survival at 3, 6, 9 and 12 months and then, 6-monthly for up to 4-years. Secondary outcomes collected at all timepoints include overall survival, response-rate and duration and safety, with quality of life and cost-effectiveness outcomes collected 3-monthly for up to 18-months. Sub-studies include a qualitative analysis of patient acceptance of randomisation and sample collection to inform future translational studies into response/ toxicity biomarkers. Discussion DANTE is a unique prospective trial investigating the optimal duration of anti-PD-1 therapy in metastatic melanoma patients. Outcomes will inform future use of these high burden drugs. Trial registration ISRCTN15837212, 31 July 2018.

BACKGROUND A substantial number of melanoma patients develop local or metastatic recurrence, and early detection of these is vital to maximise benefit from new therapies such as inhibitors of BRAF and MEK, or immune checkpoints. This study explored the use of novel DNA copy-number profiles in circulating cell-free DNA (cfDNA) as a potential biomarker of active disease and survival. PATIENTS AND METHODS Melanoma patients were recruited from oncology and dermatology clinics in Sheffield, UK, and cfDNA was isolated from stored blood plasma. Using low-coverage whole-genome sequencing, we created copy-number profiles from cfDNA from 83 melanoma patients, 44 of whom had active disease. We used scoring algorithms to summarize copy-number aberrations and investigated their utility in multivariable logistic and Cox regression analyses. RESULTS The copy-number aberration score (CNAS) was a good discriminator of active disease (odds ratio, 3.1; 95% CI, 1.5–6.2; P = 0.002), and CNAS above or below the 75th percentile remained a significant discriminator in multivariable analysis for active disease (P = 0.019, with area under ROC curve of 0.90). Additionally, mortality was higher in those with CNASs above the 75th percentile than in those with lower scores (HR, 3.4; 95% CI, 1.5–7.9; P = 0.005), adjusting for stage of disease, disease status (active or resected), BRAF status, and cfDNA concentration. CONCLUSIONS This study demonstrates the potential of a de novo approach utilizing copy-number profiling of cfDNA as a biomarker of active disease and survival in melanoma. Longitudinal analysis of copy-number profiles as an early marker of relapsed disease is warranted.

Introduction Treatment of recurrent and metastatic melanoma has been revolutionised by targeted therapy. Inhibitors of mutant BRAF are a systemic treatment offered for patients with stage III/IV melanoma who are known to carry a mutation in BRAF. Currently patients’ BRAF mutation status is assessed through molecular analysis of tissue specimens. Cell-free DNA (cfDNA) released from tumours can be used to non-invasively detect active disease and predict survival in melanoma. cfDNA also provides a method for detecting BRAF mutations. This project aimed to ascertain BRAF mutation status in cfDNA through digital droplet PCR (ddPCR) of plasma samples from patients with melanoma. We aimed to assess the relationship between cfDNA BRAF positivity and disease relapse and progression. Methods Plasma from 100 patients with active or recently resected melanoma was obtained during previous work. 85 samples had cfDNA extracted. Tissue BRAF status was known for 57 samples. cfDNA was extracted from 1–2 ml plasma with the QIAamp circulating nucleic acid kit (QIAGEN®) following manufacturer protocol, eluting cfDNA into 100µL. cfDNA was quantified with SYBR green quantitative real-time PCR (Life Technologies), based on an 87bp GAPDH gene amplicon. ddPCR™ was performed using the Bio-Rad QX200 Droplet Generator™ and Droplet Reader as per manufacturer protocol. Analysis was performed with Bio-Rad QuantaSoft Version 1.7.4. Results Median yield of cfDNA extracted from 85 samples was 1.97 ng/ml when eluted into 100µL. This was well-correlated with previous cfDNA extraction yields from this sample set (Pearson’s r=0.6687, p10,000 droplets and were included for analysis. 12 samples contained BRAF mutant positive droplets. A 74% concordance rate between tissue BRAF mutation status and the presence/absence of cfDNA BRAF mutant positive droplets was found. 7/18 tissue BRAF mutant samples contained BRAF mutant droplets, in comparison to 2/32 tissue BRAF wild-type samples. The presence of BRAF mutant positive droplets was significantly different between the tissue BRAF mutant and tissue BRAF wild-type groups (χ2 8.3145, p=0.004). Fractional abundance of BRAF mutant droplets in the samples containing mutant droplets ranged from 0.07–0.74%. When comparing BRAF mutant droplet-containing samples and samples without BRAF mutant droplets, there was no significant difference in rate of relapse (χ2 0.0948, p=0.758), nor mortality rate (χ2 3.3959, p=0.654). Conclusion cfDNA provides a non-invasive snapshot of the tumour genome and any potential therapeutic targets held within. This work demonstrates that a very low volume of cfDNA can be used to detect BRAF mutations in patients with melanoma through ddPCR. Previous work assessing BRAF status in cfDNA has used larger volumes of cfDNA. Though our concordance rates are comparable with other studies, it is possible that using a smaller amount of cfDNA in our ddPCR has resulted in some samples being below the limit of detection for ddPCR. Longitudinal study is warranted to monitor cfDNA BRAF status and mutant fractional abundance, and whether this better correlates with relapse of disease and disease progression.

Background Targeted therapy has revolutionised the systemic treatment of melanoma. Patients with stage III/IV melanoma with a mutation in BRAF are treated with BRAF inhibitors, with BRAF mutation status being assessed by tissue analysis. Cell-free DNA (cfDNA) released from tumours provides a method for detecting BRAF mutations. This project analysed BRAF status in cfDNA through digital droplet PCR (ddPCR). We aimed to assess the relationship between cfDNA BRAF status and disease relapse and progression. Methods Plasma from 100 patients with active or recently resected melanoma was obtained during previous work. 85 samples had cfDNA extracted. Tissue BRAF status was known for 57 samples. cfDNA was extracted from 1-2ml plasma with the QIAamp circulating nucleic acid kit (QIAGEN®) following manufacturer protocol, eluting cfDNA into 100µL. cfDNA was quantified with SYBR green quantitative real-time PCR (Life Technologies), based on an 87bp GAPDH gene amplicon. ddPCR™ was performed using the Bio-Rad QX200 Droplet Generator™ and Droplet Reader as per manufacturer protocol. Analysis was performed with Bio-Rad QuantaSoft Version 1.7.4. Results Median yield of cfDNA was 1.97ng/ml. This correlated well with other yields from this sample set (Pearson’s r = 0.6687, p 10,000 droplets and were included for analysis. 12 samples contained BRAF mutant positive droplets. Concordance rate between tissue BRAF status and the presence/absence of cfDNA BRAF mutant droplets was 74%. 7/18 tissue BRAF mutant samples were cfDNA BRAF mutant positive, in contrast to 2/32 tissue BRAF wild-type samples. The presence of BRAF mutant positive droplets in cfDNA was significantly different between tissue BRAF mutant and wild-type groups (p = 0.004). The presence of BRAF mutant droplets did not confer any significant difference in rate of relapse (p = 0.758) or mortality rate (p = 0.654). Conclusions A very low volume of cfDNA can be used to detect BRAF mutations in patients with melanoma through ddPCR. Having used small yields of cfDNA, it is possible that some samples fell below the limit of detection for ddPCR. Longitudinal study is warranted to monitor cfDNA BRAF status, and whether this correlates with relapse and disease progression. Legal entity responsible for the study The authors. Funding Weston Park Cancer Charity. Disclosure All authors have declared no conflicts of interest.

The development of targeted therapies in lung cancer (mainly non-small cell lung cancer) has led to improvement in clinical outcomes and a more personalized approach to the management of these patients. This article discusses the main categories of novel targeted agents and the evidence behind their use.

Over a third of patients with lung cancer will develop bone metastases during the course of their disease, resulting in symptoms of pain and immobility, and skeletal-related events (SREs) such as fracture, hypercalcaemia, surgery or radiotherapy to bones, and malignant spinal cord compression. These reduce quality of life and increase mortality. Preclinical research has identified the interactions between tumour cells and bone that are key to tumour cell survival and associated osteolysis. These data have led to the development of drugs to prevent osteoclast-mediated bone breakdown, such as zoledronic acid and denosumab, which are now licensed for use in patients with bone metastases from solid tumours. Both zoledronic acid and denosumab reduce the risk of SREs and increase time to first SRE, with minimal side effects. In addition, denosumab improved survival in patients with lung cancer compared with zoledronic acid. Ongoing trials are testing whether these drugs can prevent the development of bone metastases from lung cancer. New bone-targeted agents showing promise in breast and prostate cancer include radium-223, cabozantinib and Src inhibitors. These agents require further evaluation in patients with lung cancer.