Increased number of metastatic lymph nodes in adenocarcinoma of the ampulla of Vater as a prognostic factor: a proposal of new nodal classification.
BACKGROUND
Although the number of metastatic lymph nodes in most gastrointestinal carcinomas is correlated inversely with prognosis, the prognostic value of the number of metastatic lymph nodes in ampullary adenocarcinoma has not been well characterized.


METHODS
Lymph node metastasis was assessed in the Surveillance, Epidemiology and End Results database in 1,057 ampullary adenocarcinomas that were operatively resected and for which at least 12 lymph nodes were examined. A complex pattern of survival versus extent of lymph node metastasis was captured by censored local regression. The impact of the extent of lymph nodes metastasis on survival was investigated by use of the K-adaptive partitioning algorithm to identify the most significant cut-off points of metastatic lymph nodes affecting survival.


RESULTS
Two significant cut-off points (0 and 2) for the metastatic lymph node segregated patients into 3 groups with clinically important differences in median survival: patients with no metastatic lymph node (477 cases) had a median survival of 91 months, patients with 1-2 metastatic lymph nodes (279 cases) had a median survival of 29 months, whereas patients with ≥3 metastatic Lymph nodes (301 cases) had a median survival of 19 months (P < .0001). These results were validated with additional single institution dataset (318 cases, P < .0001).


CONCLUSIONS
The present results suggest that the nodal classification of ampullary adenocarcinoma should be categorized N0 (no metastatic lymph node), N1 (1-2 metastatic lymph nodes), and N2 (≥3 metastatic lymph nodes).
Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
Hyo Jeong
HJ
Kang
Department of Statistics, Korea University, Seoul, Republic of Korea.
Soo-Heang
SH
Eo
Division of Hepato-Biliary and Pancreatic Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
Song Cheol
SC
Kim
Division of Hepato-Biliary and Pancreatic Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
Kwang-Min
KM
Park
Division of Hepato-Biliary and Pancreatic Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
Young-Joo
YJ
Lee
Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
Sung Koo
SK
Lee
Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
Eunsil
E
Yu
Department of Statistics, Korea University, Seoul, Republic of Korea. Electronic address: hj4cho@korea.ac.kr.
Hyungjun
H
Cho
Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea. Electronic address: smhong28@gmail.com.
Seung-Mo
SM
Hong
D000230:Adenocarcinoma / Q000401:mortality / Q000473:pathology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014670:Ampulla of Vater / Q000473:pathology; D003138:Common Bile Duct Neoplasms / Q000401:mortality / Q000473:pathology*; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D055815:Young Adult