title: Implications of peritoneal cytology for pancreatic cancer management.
abstract: OBJECTIVE
  To assess the implications of positive cytology for malignant cells (positive results) from peritoneal washings in the management of patients with pancreatic cancer.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  Referral practice in a university hospital.
  
  
  METHODS
  A total of 32 consecutive pancreatic cancer patients with positive results from peritoneal washings during a 4-year period, 17 with visible biopsy-proven intraabdominal metastases at the time of laparoscopy or laparotomy and 15 without visible metastases. A treatment-matched control group of 30 patients was randomly selected from a group of 105 patients with negative cytology for malignant cells (negative results) from peritoneal-fluid cytology.
  
  
  METHODS
  Eight of 17 patients with visible metastases underwent treatment with chemotherapy, radiation, or both; 13 of the 15 patients with no visible metastases underwent further treatment, including pancreatic resection in 2 patients and external beam radiation in 13 patients (3 with intraoperative radiation therapy).
  
  
  METHODS
  Time to metastases and mortality.
  
  
  RESULTS
  Median survival among patients with and without visible metastasis was 7.8 months and 8.6 months, respectively (P=.95), despite the fact that patients without visible metastases received more treatment. Patients without visible metastases at presentation were found to have metastatic disease as documented by computed tomographic scan or subsequent laparotomy at a median time of 2.9 months. The survival of treatment-matched patients with negative cytology was significantly longer (median, 13.5 months; P=.04).
  
  
  CONCLUSIONS
  Pancreatic cancer patients with peritoneal micrometastases have a dismal outcome even without macroscopic metastases. Since these patients do not benefit from local therapy, the finding of a positive result from peritoneal-fluid cytologic testing contraindicates further irradiation or surgery, except for specific complications.
authors.affiliation: Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston 02114, USA.
authors.forename: M A
authors.initials: MA
authors.lastname: Makary
authors.forename: A L
authors.initials: AL
authors.lastname: Warshaw
authors.forename: B A
authors.initials: BA
authors.lastname: Centeno
authors.forename: C G
authors.initials: CG
authors.lastname: Willet
authors.forename: D W
authors.initials: DW
authors.lastname: Rattner
authors.forename: C
authors.initials: C
authors.lastname: Fernández-del Castillo
mesh_terms: D015331:Cohort Studies; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D010533:Peritoneal Lavage; D010534:Peritoneal Neoplasms / Q000556:secondary*; D012189:Retrospective Studies; D016019:Survival Analysis; D015996:Survival Rate