Purpose: Up to 30% of patients with breast cancer relapse after primary treatment. There are no sensitive and reliable tests to monitor these patients and detect distant metastases before overt recurrence. Here, we demonstrate the use of personalized circulating tumor DNA (ctDNA) profiling for detection of recurrence in breast cancer. Experimental Design: Forty-nine primary patients with breast cancer were recruited following surgery and adjuvant therapy. Plasma samples (n = 208) were collected every 6 months for up to 4 years. Personalized assays targeting 16 variants selected from primary tumor whole-exome data were tested in serial plasma for the presence of ctDNA by ultradeep sequencing (average >100,000X). Results: Plasma ctDNA was detected ahead of clinical or radiologic relapse in 16 of the 18 relapsed patients (sensitivity of 89%); metastatic relapse was predicted with a lead time of up to 2 years (median, 8.9 months; range, 0.5–24.0 months). None of the 31 nonrelapsing patients were ctDNA-positive at any time point across 156 plasma samples (specificity of 100%). Of the two relapsed patients who were not detected in the study, the first had only a local recurrence, whereas the second patient had bone recurrence and had completed chemotherapy just 13 days prior to blood sampling. Conclusions: This study demonstrates that patient-specific ctDNA analysis can be a sensitive and specific approach for disease surveillance for patients with breast cancer. More importantly, earlier detection of up to 2 years provides a possible window for therapeutic intervention.

Overall survival (OS) is a composite clinical endpoint in hepatocellular carcinoma (HCC) due to the mutual influence of cirrhosis and active malignancy in dictating patient's mortality. The ALBI grade is a recently described index of liver dysfunction in hepatocellular carcinoma, based solely on albumin and bilirubin levels. Whilst accurate, this score lacks cross-validation, especially in intermediate stage HCC, where OS is highly heterogeneous. We evaluated the prognostic accuracy of the ALBI grade in estimating OS in a large, multi-centre study of 2426 patients, including a large proportion of intermediate stage patients treated with chemoembolization (n=1461) accrued from Europe, the United States and Asia. Analysis of survival by primary treatment modality confirmed the ALBI grade as a significant predictor of patient OS after surgical resection (p<0.001), transarterial chemoembolization (p<0.001) and sorafenib (p<0.001). Stratification by Barcelona Clinic Liver Cancer stage confirmed the independent prognostic value of the ALBI across the diverse stages of the disease, geographical regions of origin and time of recruitment to the study (p<0.001). In this large, multi-centre retrospective study, the ALBI grade satisfied the criteria for accuracy and reproducibility following statistical validation in Eastern and Western HCC patients, including those treated with chemoembolization. Consideration should be given to the ALBI grade as a stratifying biomarker of liver reserve in routine clinical practice. Liver failure is a key determinant influencing the natural history of hepatocellular carcinoma (HCC). In this large multi-centre study we externally validate a novel biomarker of liver functional reserve, the ALBI grade, across all the stages of HCC.