Correspondence

Imaging of the Hepatobiliary Tract

N Engl J Med 1997; 337:1391-1392November 6, 1997

Article

To the Editor:

The excellent review of imaging of the hepatobiliary tract by Saini (June 26 issue)1 does not mention an important new combined radiologic and surgical method for the examination of the hepatobiliary tract — diagnostic laparoscopy combined with laparoscopic ultrasonography. This imaging technique is now being used to stage hepatic, pancreatic, and biliary tumors.2-4 It can also improve the accuracy of the selection of patients suitable for curative resection.

As Saini explained, helical computed tomography cannot easily detect liver lesions smaller than 2 cm or tumor ingrowth in surrounding structures and vascular structures. Laparoscopic ultrasonography can detect liver lesions as small as 4 mm.4 It can also provide staging information supplementary to that obtained by laparoscopy in 42 percent of patients with liver tumors, 43 percent of those with proximal bile-duct tumors, and 53 percent of those with pancreatic-head tumors.2-4 Laparoscopy can identify superficial liver metastases and peritoneal deposits, both of which are difficult to visualize with helical computed tomography or other preoperative imaging techniques. In one series, cirrhosis, which was not suspected preoperatively, was diagnosed and confirmed during laparoscopy in 12 percent of the patients with liver tumors.2 Laparoscopy has a high diagnostic yield, up to 91 percent, with respect to the diagnosis of benign as well as malignant liver abnormalities.5

In our department, patients with resectable hepatic, pancreatic, and biliary neoplasms after radiologic staging with ultrasonography and computed tomography undergo diagnostic laparoscopy combined with laparoscopic ultrasonography as a separate staging procedure. The surgeon performs the laparoscopy and then performs laparoscopic ultrasonography together with the radiologist. Only pathologically confirmed unresectable disease is an exclusion criterion for further exploration. In the period 1992–1996, we used this combined approach in 308 patients with hepatic, pancreatic, and biliary tumors.

The benefits of diagnostic laparoscopy combined with laparoscopic ultrasonography were large in patients with tumors of the hepatobiliary tract, whereas in our series the advantage of this approach (in terms of avoiding laparotomy) in patients with periampullary tumors was only 15 percent.6 The sensitivity of this method for the detection of metastases was 95 percent for proximal bile-duct tumors, 80 percent for primary and 79 percent for secondary liver tumors, and 59 percent for periampullary tumors. Therefore, among patients with resectable hepatic, pancreatic, and biliary tumors after conventional radiologic staging, this procedure should be performed in those with proximal bile-duct tumors and liver tumors.

Els J.M. Nieveen van Dijkum, M.D.
Laurens T. de Wit, M.D.
Dirk J. Gouma, M.D.
Academic Medical Center, 1105 AZ Amsterdam, the Netherlands

6 References

1. 1

   Saini S. Imaging of the hepatobiliary tract. N Engl J Med 1997;336:1889-1894
   Full Text | Web of Science | Medline

2. 2

   John TG, Greig JD, Crosbie JL, Miles WF, Garden OJ. Superior staging of liver tumors with laparoscopy and laparoscopic ultrasound. Ann Surg 1994;220:711-719
   CrossRef | Web of Science | Medline

3. 3

   John TG, Greig JD, Carter DC, Garden OJ. Carcinoma of the pancreatic head and periampullary region: tumor staging with laparoscopy and laparoscopic ultrasonography. Ann Surg 1995;221:156-164
   CrossRef | Web of Science | Medline

4. 4

   van Delden OM, de Wit LT, Nieveen van Dijkum EJ, Smits NJ, Gouma DJ, Reeders JW. Value of laparoscopic ultrasonography in staging of proximal bile duct tumors. Ultrasound Med 1997;16:7-12
   Web of Science | Medline

5. 5

   Vargas C, Jeffers LJ, Bernstein D, et al. Diagnostic laparoscopy: a 5-year experience in a hepatology training program. Am J Gastroenterol 1995;90:1258-1262
   Web of Science | Medline

6. 6

   van Dijkum EJ, de Wit LT, van Delden OM, et al. The efficacy of laparoscopic staging in patients with upper gastrointestinal tumors. Cancer 1997;79:1315-1319
   CrossRef | Web of Science | Medline

Author/Editor Response

Dr. Saini replies:

To the Editor: Technical advances in imaging of the liver and biliary tract are proceeding at an ever-increasing pace. Examples include those related not only to the miniaturization of tools for direct and indirect visualization but also to the formulation of novel diagnostic pharmaceutical agents, which can permit imaging of anatomy as well as physiology.1 However, these new imaging strategies should be incorporated into the routine practice of medicine at a relatively slower pace and only after their benefits in terms of outcomes have been established. The experience of Dr. Nieveen van Dijkum and colleagues with combined diagnostic laparoscopy and laparoscopic ultrasonography suggests that the approach deserves further clinical evaluation.

Sanjay Saini, M.D.
Massachusetts General Hospital, Boston, MA 02114

1 References

1. 1

   Van Beers BE, Gallez B, Pringot J. Contrast-enhanced MR imaging of the liver. Radiology 1997;203:297-306
   Web of Science | Medline