title: Single punch, double biopsy.
abstract: OBJECTIVE
  In lethal primary metastatic prostate cancer, biopsy material is often the only accessible cancer tissue. Lack of tissue quantity limited the use of biopsy cores for analyzing higher numbers of molecular markers and standard histopathologic evaluation for clinical diagnosis simultaneously. Recent advances in single cell analytics have paved the way to characterize a tumor in more depth from minute input material such as biopsies. We therefore aimed to develop a biopsy needle, which generates two cores side by side from the same punch: one for standard histopathologic analysis to allow for routine diagnostics and the second one for single cell analytics.
  
  
  METHODS
  On the basis of a conventional punch biopsy needle we have milled two parallel longitudinal rifts into the needles shat which are separated by a 100 µm thick metal sheet. Each rift can harbor a single tissue core.
  
  
  RESULTS
  Two cores from the same punch were generated reproducibly from a radical prostatectomy specimen and showed congruent results in histopathologic analysis. Both cores yielded equally sufficient material for standard H&E staining and histopathological evaluation.
  
  
  CONCLUSIONS
  Our modified biopsy system will allow for simultaneous acquisition of tissue cores for diagnostic and scientific analysis from solid tumors or metastatic sites.
authors.affiliation: Department of Urology, University of Freiburg Medical Centre, Hugstetter Strasse 55, 79106 Freiburg, Germany.
authors.forename: Malte
authors.initials: M
authors.lastname: Krönig
authors.affiliation: Department of Radiation Oncology, University of Freiburg Medical Centre, Hugstetter Strasse 55, 79106 Freiburg, Germany.
authors.forename: Norbert
authors.initials: N
authors.lastname: Nanko
authors.affiliation: Department of Clinical Pathology, University of Freiburg Medical Centre, Breisacher Strasse 155a, 79106 Freiburg, Germany.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Drendel
authors.affiliation: Department of Clinical Pathology, University of Freiburg Medical Centre, Breisacher Strasse 155a, 79106 Freiburg, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Werner
authors.affiliation: Department of Urology, University of Freiburg Medical Centre, Hugstetter Strasse 55, 79106 Freiburg, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Schultze-Seemann
authors.affiliation: Department of Radiation Oncology, University of Freiburg Medical Centre, Hugstetter Strasse 55, 79106 Freiburg, Germany.
authors.forename: Anca L
authors.initials: AL
authors.lastname: Grosu
authors.affiliation: Department of Urology, University of Freiburg Medical Centre, Hugstetter Strasse 55, 79106 Freiburg, Germany.
authors.forename: A Cordula
authors.initials: AC
authors.lastname: Jilg
keywords: Needle biopsy; Primary tissue; Prostate cancer; Single cell; Tissue heterogeneity