Purpose: Despite conflicting data regarding survival after curative surgery, little is known about the prognosis of metastatic gastric cancer (MGC) in young adults. The current study was performed to determine whether younger age is an independent prognostic factor among MGC patients receiving first-line chemotherapy and to evaluate how age relates to other known prognostic parameters.

Methods: The records of 1843 MGC patients who were consecutively treated with first-line combination chemotherapy at Samsung Medical Center (Seoul, Korea) between 2000 and 2007, including 570 patients aged 45 years or younger, were retrieved from a prospective cancer chemotherapy database.

Results: In the younger group, there were significantly more bone metastases, ascites, poor performance status, low albumin, elevated alkaline phosphatase, and resections that were non-curative than in the older patients. Progression-free survival (PFS) and overall survival (OS) was shorter in younger patients (PFS, 4.2 months; OS, 7.1 months) than in older ones (PFS, 5.1 months; OS, 8.4 months). Nonetheless, younger age did not show an independent association with PFS or OS. Stratified analyses showed that younger age was related with poor outcome in the subgroups of good performance status and no bone metastasis.

Conclusion: When matched for other prognostic factors, the prognosis of younger MGC patients receiving first-line combination chemotherapy does not differ from that of older patients. The poor survival of younger patients may be attributed to the association with other adverse prognostic factors.