title: Pattern of carcinoembryonic antigen drop after laparoscopic radiofrequency ablation of liver metastasis from colorectal carcinoma.
abstract: BACKGROUND
  Laparoscopic radiofrequency ablation (RFA) is being increasingly used for local control of hepatic metastasis from colorectal carcinoma (CRC). After surgical resection of colorectal liver metastasis, carcinoembryonic antigen (CEA) values fall within 2 weeks, making this a useful parameter to follow shortly after surgery. Little is known, however, about the expected pattern of the CEA drop after RFA.
  
  
  METHODS
  From September 1998 to October 2002, RFA to CRC liver metastasis was performed on 144 patients. A subset of 17 patients were studied who had no evidence of extrahepatic disease preoperatively, had all detectable tumor ablated intraoperatively, and who on long-term follow-up (up to 15 months) had no evidence of recurrent disease. Serum CEA was determined preoperatively, on the first postoperative day, at 1 week, and every 3 months afterwards. A computed tomography (CT) scan of the abdomen and pelvis was obtained every 3 months postoperatively.
  
  
  RESULTS
  Ten (58.8%) patients showed an increase in CEA on postoperative Day 1, averaging 38.3% compared with the preoperative value. CEA then fell to 50% of the preoperative value, on average, on Day 7 postoperatively and only reached its nadir at 3 months.
  
  
  CONCLUSIONS
  Unlike resection patients, those undergoing ablation show an initial rise in CEA, probably due to release from the ablated tissue. Although heating of RFA would be expected to destroy CEA, the initial rise and slow drop postoperatively argue for a release of immunoreactive CEA from the ablated zone. This slow decline in CEA indicates that several months should pass before assessing the extent of potential residual disease.
authors.affiliation: Department of General Surgery, The Cleveland Clinic Foundation, Cleveland, Ohio, USA. mghanamah@yahoo.com
authors.forename: Mohammed
authors.initials: M
authors.lastname: Ghanamah
authors.forename: Eren
authors.initials: E
authors.lastname: Berber
authors.forename: Allan
authors.initials: A
authors.lastname: Siperstein
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002272:Carcinoembryonic Antigen / Q000097:blood*; D002277:Carcinoma / Q000378:metabolism* / Q000556:secondary / Q000601:surgery*; D017115:Catheter Ablation; D015179:Colorectal Neoplasms / Q000378:metabolism* / Q000556:secondary / Q000601:surgery*; D005260:Female; D006801:Humans; D010535:Laparoscopy; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D011446:Prospective Studies; D013997:Time Factors
chemical_list: D002272:Carcinoembryonic Antigen