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Purpose The expanding number of targeted therapeutics for non-small cell lung cancer (NSCLC) necessitates real-time tumor genotyping, yet tissue biopsies are difficult to perform serially and often yield inadequate DNA for next-generation sequencing (NGS). We evaluated the feasibility of using cell-free circulating tumor DNA (ctDNA) NGS as a complement or alternative to tissue NGS. Experimental Design 112 plasma samples obtained from a consecutive study of 102 prospectively enrolled patients with advanced NSCLC were subjected to ultra-deep sequencing of up to 70 genes and matched with tissue samples, when possible. Results We detected 275 alterations in 45 genes, and at least one alteration in the ctDNA for 86 of 102 patients (84%), with EGFR variants being most common. ctDNA NGS detected 50 driver and 12 resistance mutations, and mutations in 22 additional genes for which experimental therapies, including clinical trials, are available. While ctDNA NGS was completed for 102 consecutive patients, tissue sequencing was only successful for 50 patients (49%). Actionable EGFR mutations were detected in 24 tissue and 19 ctDNA samples, yielding concordance of 79%, with a shorter time interval between tissue and blood collection associated with increased concordance (p=0.038). ctDNA sequencing identified 8 patients harboring a resistance mutation who developed progressive disease while on targeted therapy, and for whom tissue sequencing wasn’t possible. Conclusions Therapeutically targetable driver and resistance mutations can be detected by ctDNA NGS, even when tissue is unavailable, thus allowing more accurate diagnosis, improved patient management, and serial sampling to monitor disease progression and clonal evolution.

The Vitatex cell-adhesion matrix (CAM) platform allows for isolation of invasive circulating tumor cells (iCTCs). Here we sought to determine the utility of prostate-specific membrane antigen (PSMA) as a metastatic castration-resistant prostate cancer (mCRPC) iCTC biomarker, to identify solitary cells and clusters of iCTCs expressing either epithelial, mesenchymal, or stem cell markers, and to explore the feasibility of iCTC epigenomic analysis. CTCs were isolated and enumerated simultaneously using the Vitatex and CellSearch platforms in 23 men with mCRPC. CAM-avid iCTCs were identified as nucleated cells capable of CAM uptake, but without detectable expression of hematopoietic lineage (HL) markers including CD45. iCTCs were enumerated immunocytochemically (ICC) and by flow cytometry. Whole-genome methylation status was determined for iCTCs using the Illumina HumanMethylation27 BeadChip. Thirty-four samples were collected for iCTC analysis. A median of 27 (range 0-800) and 23 (range 2-390) iCTCs/mL were detected by ICC and flow, respectively. In a subset of 20 samples, a median of seven CTCs/ mL (range 0-85) were detected by the CellSearch platform compared to 26 by the CAM platform. iCTC clusters were observed in 17% of samples. iCTCs expressing PSMA as well as markers of EMT and stemness were detectable. The iCTC methylation profile highly resembled mCRPC. More CTCs were recovered using the CAM platform than the CellSearch platform, and the CAM platform allowed for the detection of iCTC clusters, iCTCs expressing EMT and stem-cell markers, and characterization of the iCTC methylome. Correlation with clinical data in future studies may yield further insight into the functional significance of these findings.Metastatic castration-resistant prostate cancer (mCRPC) is the lethal form of the disease. Although new treatments improve survival, 1-3 none are curative and all patients eventually develop treatment resistance followed by disease progression. mCRPC biopsies are seldom performed since they are rarely medically necessary. Thus, relatively less is known about the later genetic changes that allow mCRPC to grow and survive despite treatment with hormonal-and chemotherapeutics.Isolation, enumeration and genomic profiling of circulating tumor cells (CTCs) is a fairly non-invasive means to characterize and discover the genetic changes that occur in advanced cancer. The CellSearch V R assay by Veridex was approved by the United States Food and Drug

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Background Women with a BRCA mutation have significantly elevated breast cancer risk which can be reduced by >90% with bilateral prophylactic mastectomies (BPMs). We sought to compare a cohort of BRCA mutation carriers choosing BPM versus breast surveillance to better elucidate factors that may impact decision making. Methods Women with a BRCA mutation were retrospectively identified from a prospectively maintained database. The surveillance cohort (n=313) consisted of women seen in a high-risk clinic between 2014–2016; the surgery cohort (n=142) consisted of women who underwent BPM between 2010–2016. Clinical and familial factors were compared between the groups. Results Women choosing BPM were more likely to have a BRCA1 than BRCA2 mutation compared to the surveillance group (57% vs 45%, p=0.02) and were less likely to have a personal history of ovarian cancer (10% vs 20%, p=0.01). Women undergoing BPM were more likely to be married (78% vs 62%, p=0.01), to have more children (median 2 vs 1, p<0.001), and to have undergone a prophylactic oophorectomy (61% vs 37%, p<0.001). Women choosing BPM had more first-degree relatives (63% vs 48%, p=0.01) or a sister (23% vs 14%, p=0.02) with a history of breast cancer and were more likely to have a family member with ovarian cancer under age 40 (9% vs 4%, p=0.03). There was no difference in the number of prior breast biopsies or history of atypia/LCIS. Conclusion The decision to undergo BPM appears multifactorial, with gene mutation, family history, and relationships appearing to have the strongest influence on decision making.