title: Disseminated tumor cells in bone marrow following definitive radiotherapy for intermediate or high-risk prostate cancer.
abstract: BACKGROUND
  The purpose of this study was to explore the prevalence of disseminated tumor cells (DTCs) in bone marrow (BM) of clinically progression-free prostate cancer (PC) patients at least 2 years after curatively intended radiotherapy (RT) with or without adjuvant hormone treatment.
  
  
  METHODS
  All patients were T(1-3)N(0)M(0) with intermediate or high risk of progression. Median time from RT to BM sampling was 5 years (2-8). A standardized immunocytochemical method applying the anticytokeratin antibodies AE1/AE3 was used for DTCs detection in 130 patients. Morphological characterization of immunostained cells was performed to exclude false positive cells. The post-treatment BM was explored in relation to pre-treatment risk factors, treatment strategy and serum levels of Testosterone and PSA at the time of BM sampling. Longitudinal changes in BM status were studied in a sub-group of 109 patients who also had donated BM prior to treatment.
  
  
  RESULTS
  Post-treatment BM-aspirates were positive for DTCs in 17% of cases without correlation to any of the tested variables. Out of 14 patients who had DTCs in BM prior to treatment, all but one had become post-treatment negative. Out of 95 patients with pre-treatment negative BM status, 18 (19%) had become post-treatment positive.
  
  
  CONCLUSIONS
  DTCs in BM were found in 17% of clinically progression-free PC patients following RT. The detection of these cells may provide PSA-independent prognostic information remaining to be explored by prolonged follow-up.
authors.affiliation: Norwegian Radium Hospital, Faculty of Medicine, University of Oslo, Oslo, Norway. arne.berg@radiumhospitalet.no
authors.forename: Arne
authors.initials: A
authors.lastname: Berg
authors.forename: Øyvind S
authors.initials: ØS
authors.lastname: Bruland
authors.forename: Sophie D
authors.initials: SD
authors.lastname: Fosså
authors.forename: Jahn M
authors.initials: JM
authors.lastname: Nesland
authors.forename: Aasmund
authors.initials: A
authors.lastname: Berner
authors.forename: Cecilie
authors.initials: C
authors.lastname: Schirmer
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Lilleby
mesh_terms: D000368:Aged; D001853:Bone Marrow / Q000473:pathology*; D018450:Disease Progression; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011471:Prostatic Neoplasms / Q000473:pathology* / Q000532:radiotherapy*; D018570:Risk Assessment; D013194:Staining and Labeling; D013997:Time Factors