title: Increase in the incidence of peritoneal collagen balls over a 10-year period.
abstract: OBJECTIVE
  To describe the detection of collagen balls in peritoneal washings over a 10-year period, revealing an unexpected and unexplained higher incidence than in the past.
  
  
  METHODS
  Reports of routinely processed, Papanicolaou-stained smears and cytospins and hematoxylineosin-stained cell blocks from peritoneal washes and ascitic fluids seen over an 8-year period (1995-2002) were reviewed, and the percentage of specimens in which collagen balls were noted was determined. To rule out a learning curve phenomenon, the first 100 consecutive peritoneal washings and ascitic specimens from years 1993-2001 plus 2002 were rescreened, and the percentage of specimens containing collagen balls was determined.
  
  
  RESULTS
  The percentages of cases with collagen balls increased steadily beginning with 8 of 467 cases (3.2%) in 1995 to 185 of 650 (28.5%) in 2002, as reported in the case records. Rescreened cases also showed a similar increase, 4.0% in 1993 to 29% in 2002. No procedural modifications were made in specimen processing during this interval, nor are we aware of any procedural change in obtaining cytologic samples.
  
  
  CONCLUSIONS
  An unexplained 7-fold increase in the percentage of peritoneal samples with collagen balls occurred over a 10-year period. This increase cannot be attributed to changes in specimen handling or to a learning curve phenomenon. This finding is of unknown significance and may warrant further investigation.
authors.affiliation: Division of Cytopathology, Department of Pathology, Box 1194, Mount Sinai Medical Center, 1 Gustave L. Levy Place, New York, New York 10029, USA. arnold.szporn@mssm.edu
authors.forename: Arnold H
authors.initials: AH
authors.lastname: Szporn
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Chen
authors.forename: Maoxin
authors.initials: M
authors.lastname: Wu
authors.forename: Edmond
authors.initials: E
authors.lastname: Sabo
authors.forename: David E
authors.initials: DE
authors.lastname: Burstein
mesh_terms: D001202:Ascitic Fluid / Q000473:pathology*; D003094:Collagen / Q000032:analysis*; D005260:Female; D006801:Humans; D008297:Male; D065006:Papanicolaou Test; D010533:Peritoneal Lavage; D012189:Retrospective Studies; D013194:Staining and Labeling; D014626:Vaginal Smears
chemical_list: D003094:Collagen