title: Clinical significance of lymph node micrometastasis in ampullary carcinoma.
abstract: BACKGROUND
  This study aimed to clarify the clinical significance of lymph node micrometastasis in ampullary carcinoma.
  
  
  METHODS
  Pancreaticoduodenectomy with regional lymphadenectomy was performed for 50 consecutive patients with ampullary carcinoma. A total of 1,283 regional lymph nodes (median, 25 per patient) were examined histologically for metastases. Overt metastasis was defined as metastasis detected during routine histologic examination with hematoxylin and eosin. Micrometastasis was defined as metastasis first detected by immunohistochemistry with an antibody against cytokeratins 7 and 8. The median follow-up period was 119 months after resection.
  
  
  RESULTS
  Overt metastasis was positive in 90 lymph nodes from 27 patients. Micrometastasis was positive in 33 lymph nodes from 12 patients, all of whom also had overt nodal metastases. Patients with nodal micrometastasis had a larger number of lymph nodes with overt metastasis (median, 3.5) than those without (median, 0; P<0.001). Overt metastasis to distant nodes (superior mesenteric nodes, para-aortic nodes) was more frequent (P=0.001 and P=0.038, respectively) in patients with nodal micrometastasis. Nodal micrometastasis was found to be a strong independent prognostic factor on univariate (P<0.0001) and multivariate (relative risk, 5.085; P=0.007) analyses. From among the 27 patients with overt nodal metastasis, the outcome after resection was significantly worse in the patients with nodal micrometastasis (median survival time of 11 months) than in those without (median survival time of 63 months; P=0.0009).
  
  
  CONCLUSIONS
  Immunohistochemically detected lymph node micrometastasis indicates intensive lymphatic spread, and thus adversely affects the survival of patients with ampullary carcinoma.
authors.affiliation: Division of Digestive and General Surgery, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Niigata City 951-8510, Japan. shiray@med.niigata-u.ac.jp
authors.forename: Eiko
authors.initials: E
authors.lastname: Sakata
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Shirai
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Yokoyama
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Wakai
authors.forename: Jun
authors.initials: J
authors.lastname: Sakata
authors.forename: Katsuyoshi
authors.initials: K
authors.lastname: Hatakeyama
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014670:Ampulla of Vater; D014408:Biomarkers, Tumor / Q000032:analysis; D003138:Common Bile Duct Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007633:Keratins / Q000032:analysis; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000737:chemistry; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D016577:Pancreaticoduodenectomy; D011379:Prognosis; D015996:Survival Rate
chemical_list: D014408:Biomarkers, Tumor; D007633:Keratins