title: EUS-guided FNA of peritoneal carcinomatosis in patients with unknown primary malignancy.
abstract: BACKGROUND
  EUS-guided FNA is a well-recognized technique for sampling the pancreas, peri-intestinal lymph nodes, and mass lesions. The role of EUS-guided FNA in the diagnosis of peritoneal carcinomatosis has not been well studied.
  
  
  OBJECTIVE
  We aimed to determine the feasibility and success in sampling lesions in the peritoneum suspicious for carcinomatosis without a primary source.
  
  
  METHODS
  An observational study.
  
  
  METHODS
  A tertiary referral center.
  
  
  METHODS
  Consecutive patients who underwent EUS-guided FNA of peritoneal deposits.
  
  
  RESULTS
  During a span of 3 years, 4 patients underwent transgastric or transduodenal EUS-guided FNA of peritoneal lesions with a curvilinear echoendoscope. All of these lesions were imaged by abdominal CT scan. The EUS findings of the nodules appeared round, relatively hypoechoic to the surrounding tissue, but hyperechoic when compared with the surrounding low-volume ascites where the lesions floated. Four passes were performed per case, and the diagnosis was achieved on a median of 2 passes (range 1-4). All patients received intravenous antibiotics during the procedure. Two patients had metastatic adenocarcinoma, 1 patient had lymphoma, and 1 patient had metastatic breast carcinoma. Diagnostic laparoscopy/laparotomy was avoided in all patients. No complications, particularly peritonitis, were encountered.
  
  
  CONCLUSIONS
  Observational study with a small sample size.
  
  
  CONCLUSIONS
  Transgastric or transduodenal EUS-guided FNA for peritoneal carcinomatosis is feasible and safe. In the setting of an unknown primary cancer, EUS-guided FNA facilitates acquisition of tissues for treatment allocation, thus avoiding the need for laparoscopy or laparotomy.
authors.affiliation: Department of Medicine, Division of Gastroenterology and Hepatology, University of Alabama in Birmingham, Birmingham, Alabama 35294-0007, USA.
authors.forename: Shajan
authors.initials: S
authors.lastname: Peter
authors.forename: Isam
authors.initials: I
authors.lastname: Eltoum
authors.forename: Mohamad A
authors.initials: MA
authors.lastname: Eloubeidi
mesh_terms: D000328:Adult; D000368:Aged; D044963:Biopsy, Fine-Needle / Q000379:methods*; D002277:Carcinoma / Q000473:pathology*; D019160:Endosonography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009382:Neoplasms, Unknown Primary / Q000473:pathology*; D010534:Peritoneal Neoplasms / Q000473:pathology*