Comparison of gastric cancer survival following R0 resection in the United States and Korea using an internationally validated nomogram.
OBJECTIVE
To compare disease-specific survival (DSS) between the US and Korea following R0 resection for gastric carcinoma (GC).


BACKGROUND
Many studies have described decreased 5-year survival after curative gastrectomy for GC in the West compared with the East. Although clinicopathological presentations of GC are known to vary widely between Eastern and Western countries, including histology, tumor location, and stage at presentation, it remains unclear whether these factors account for differences in survival.


METHODS
All patients undergoing curative intent resections (R0) for GC (1995-2005) were evaluated in 2 independent, single-institution prospectively maintained databases from the US (711 patients) and Korea (1646 patients). Patients receiving neoadjuvant chemotherapy were excluded from this analysis. Patient, surgical and pathologic variables were compared. DSS was determined via multivariate analysis using prognostic variables from an internationally validated GC nomogram that estimates the probability of 5- and 9-year survival.


RESULTS
Age and body mass index were significantly higher in US patients. Location of tumors was more often proximal in the United States (39% vs. 9%, P < 0.0001) and distal in Korea (54% vs. 33%, P < 0.0001). Korean patients had more early stage tumors (42% vs. 28% stage Ia, P < 0.0001) with a higher number of lymph nodes identified (97% vs. 79%, >or=15 lymph nodes, P < 0.0001). The 5-year DSS was higher in Korea than in the United States. After multivariate analysis, applying factors used in the nomogram, DSS of Korean GC patients remained significantly better than that of US patients (HR = 1.3, 95% CI; 1.0-1.6, P = 0.008).


CONCLUSIONS
This study demonstrates better survival for GC patients in Korea compared with the US as determined by multivariate analysis with a validated gastric cancer nomogram. Multiple possibilities can explain this difference.
Strong
Vivian E
VE
Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, NY, USA.
Song
Kyo Young
KY
Park
Cho Hyun
CH
Jacks
Lindsay M
LM
Gonen
Mithat
M
Shah
Manish
M
Coit
Daniel G
DG
Brennan
Murray F
MF
D000230:Adenocarcinoma / Q000401:mortality* / Q000473:pathology / Q000556:secondary / Q000601:surgery; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018572:Disease-Free Survival; D005260:Female; D005743:Gastrectomy; D006801:Humans; D007723:Korea / Q000453:epidemiology; D008197:Lymph Node Excision; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D049451:Nomograms; D013274:Stomach Neoplasms / Q000401:mortality* / Q000473:pathology / Q000601:surgery; D015996:Survival Rate; D014481:United States / Q000453:epidemiology; D055815:Young Adult