Faculty Collaboration Database

Comparison of a lymph node ratio-based staging system with the 7th AJCC system for gastric cancer: analysis of 18,043 patients from the SEER database. Ann Surg 2012 Mar;255(3):478-85

Date

02/15/2012

Pubmed ID

22330040

DOI

10.1097/SLA.0b013e31824857e2

Scopus ID

2-s2.0-84862813216 (requires institutional sign-in at Scopus site)   171 Citations

Abstract

OBJECTIVES: The American Joint Committee on Cancer (AJCC) staging system for gastric cancer bases N status on absolute number of metastatic nodes, regardless of the number of examined nodes. We examined a modified staging system utilizing node ratio (Nr), the ratio of metastatic to examined nodes.

METHODS: A total of 18,043 gastric cancer patients who underwent gastrectomy were identified from the US Surveillance, Epidemiology, and End Results (SEER) database. A training set was divided into 5 Nr groups, and a TNrM staging system was constructed. Median survival and overall survival, based on 7th edition AJCC and TNrM staging systems, were compared, and the analysis was repeated in a validation set.

RESULTS: Median examined nodes were 10 to 11. For the training set, overall survival for all 5 AJCC N categories was significantly different when subgrouped into 15 or fewer versus more than 15 examined nodes, but overall survival was similar regardless of the number of examined nodes in 4 of 5 Nr categories. Seven AJCC stages had statistically different overall survival between subgroups, whereas only 1 TNrM stage had statistically different overall survival between subgroups. When misclassification was defined as any subgroup in which median survival fell outside the 95% confidence interval of the group's overall median survival, AJCC staging misclassified 57% of patients and TNrM staging misclassified only 12%. Similar results were found in the validation set.

CONCLUSIONS: The AJCC system classifies SEER gastric cancer patients into stages in which subgroups often have wide variations in survival. For patients undergoing limited lymph node analysis, the proposed TNrM system may predict survival more accurately.

Author List

Wang J, Dang P, Raut CP, Pandalai PK, Maduekwe UN, Rattner DW, Lauwers GY, Yoon SS

Author

Ugwuji N. Maduekwe MD Associate Dean, Associate Professor in the Surgery department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Aged
Female
Humans
Lymph Nodes
Lymphatic Metastasis
Male
Neoplasm Staging
SEER Program
Stomach Neoplasms