title: Detection of cancer DNA in plasma of patients with early-stage breast cancer.
abstract: OBJECTIVE
  Detecting circulating plasma tumor DNA (ptDNA) in patients with early-stage cancer has the potential to change how oncologists recommend systemic therapies for solid tumors after surgery. Droplet digital polymerase chain reaction (ddPCR) is a novel sensitive and specific platform for mutation detection.
  
  
  METHODS
  In this prospective study, primary breast tumors and matched pre- and postsurgery blood samples were collected from patients with early-stage breast cancer (n = 29). Tumors (n = 30) were analyzed by Sanger sequencing for common PIK3CA mutations, and DNA from these tumors and matched plasma were then analyzed for PIK3CA mutations using ddPCR.
  
  
  RESULTS
  Sequencing of tumors identified seven PIK3CA exon 20 mutations (H1047R) and three exon 9 mutations (E545K). Analysis of tumors by ddPCR confirmed these mutations and identified five additional mutations. Presurgery plasma samples (n = 29) were then analyzed for PIK3CA mutations using ddPCR. Of the 15 PIK3CA mutations detected in tumors by ddPCR, 14 of the corresponding mutations were detected in presurgical ptDNA, whereas no mutations were found in plasma from patients with PIK3CA wild-type tumors (sensitivity 93.3%, specificity 100%). Ten patients with mutation-positive ptDNA presurgery had ddPCR analysis of postsurgery plasma, with five patients having detectable ptDNA postsurgery.
  
  
  CONCLUSIONS
  This prospective study demonstrates accurate mutation detection in tumor tissues using ddPCR, and that ptDNA can be detected in blood before and after surgery in patients with early-stage breast cancer. Future studies can now address whether ptDNA detected after surgery identifies patients at risk for recurrence, which could guide chemotherapy decisions for individual patients.
authors: The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21287.
authors: Julia A
authors: JA
authors: Beaver
authors: The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21287.
authors: Danijela
authors: D
authors: Jelovac
authors: Christian Medical College Vellore, Tamil Nadu, India 632004.
authors: Sasidharan
authors: S
authors: Balukrishna
authors: The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21287.
authors: Rory
authors: R
authors: Cochran
authors: The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21287.
authors: Sarah
authors: S
authors: Croessmann
authors: The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21287.
authors: Daniel J
authors: DJ
authors: Zabransky
authors: The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21287.
authors: Hong Yuen
authors: HY
authors: Wong
authors: The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21287.
authors: Patricia Valda
authors: PV
authors: Toro
authors: The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21287.
authors: Justin
authors: J
authors: Cidado
authors: The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21287.
authors: Brian G
authors: BG
authors: Blair
authors: The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21287.
authors: David
authors: D
authors: Chu
authors: University of Pittsburgh Hillman Cancer Center, Pittsburgh, PA 15213-1863.
authors: Timothy
authors: T
authors: Burns
authors: Massachusetts General Hospital, Boston, MA 02114-2696.
authors: Michaela J
authors: MJ
authors: Higgins
authors: The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21287.
authors: Vered
authors: V
authors: Stearns
authors: The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21287.
authors: Lisa
authors: L
authors: Jacobs
authors: The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21287.
authors: Mehran
authors: M
authors: Habibi
authors: The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21287.
authors: Julie
authors: J
authors: Lange
authors: The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21287.
authors: Paula J
authors: PJ
authors: Hurley
authors: The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21287.
authors: Josh
authors: J
authors: Lauring
authors: The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21287.
authors: Dustin
authors: D
authors: VanDenBerg
authors: The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21287.
authors: Jill
authors: J
authors: Kessler
authors: The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21287.
authors: Stacie
authors: S
authors: Jeter
authors: RainDance Technologies, Billerica, MA 01821.
authors: Michael L
authors: ML
authors: Samuels
authors: Bio-Rad Laboratories, Digital Biology Center, Pleasanton, CA 94566.
authors: Dianna
authors: D
authors: Maar
authors: The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21287.
authors: Leslie
authors: L
authors: Cope
authors: The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21287.
authors: Ashley
authors: A
authors: Cimino-Mathews
authors: The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21287.
authors: Pedram
authors: P
authors: Argani
authors: The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21287.
authors: Antonio C
authors: AC
authors: Wolff
authors: The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21287.
authors: Ben H
authors: BH
authors: Park
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000235:genetics* / Q000601:surgery; D058534:Class I Phosphatidylinositol 3-Kinases; D004252:DNA Mutational Analysis / Q000379:methods; D004273:DNA, Neoplasm / Q000097:blood* / Q000737:chemistry / Q000235:genetics*; D005091:Exons / Q000235:genetics; D005260:Female; D006801:Humans; D008875:Middle Aged; D009154:Mutation; D009367:Neoplasm Staging; D019869:Phosphatidylinositol 3-Kinases / Q000235:genetics; D016133:Polymerase Chain Reaction / Q000379:methods; D011184:Postoperative Period; D057234:Preoperative Period; D011446:Prospective Studies; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D004273:DNA, Neoplasm; D019869:Phosphatidylinositol 3-Kinases; D058534:Class I Phosphatidylinositol 3-Kinases; C484760:PIK3CA protein, human