Clinicopathological characteristics of alpha-fetoprotein-producing gastric cancer

Abstract

Purpose: α-fetoprotein (AFP)-producing gastric cancer is a rare tumor with high rates of liver metastasis and a poor prognosis. Many studies have been performed but there have been no comprehensive investigations of the clinicopathological and prognosis.

Materials and methods: Six hundred ninety four patients with gastric cancer who underwent a curative gastric resection in Hanyang University Hospital from February 2001 to December 2008 were evaluated retrospectively after excluding active or chronic hepatits, liver cirrhosis and preoperative distant metastasis. Among them, thirty five patients had an elevated serum level of AFP (>7 ng/ml) preoperatively. The clinicopathological features of AFP-producing gastric cancer were analyzed.

Results: There was poorer differentiation, a higher incidence of lymph node metastasis, more marked lymphatic and vascular invasion in the AFP-positive group than in the AFP-negative group. The 5-year survival rate of the AFP-positive group was significantly poorer than that in the AFP-negative group (66% vs. 80%, P=0.002). A significantly higher incidence of liver metastasis was observed in the AFP-positive group than in the AFP-negative group (14.3% vs. 3.6%, P=0.002) with a shorter median time period from the operation to the metachronous liver metastasis (3.7 months vs. 14.1 months, P=0.043). Multivariate survival analysis revealed the depth of invasion, degree of lymph node metastasis and AFP-positivity to be the independent prognostic factors.

Conclusions: AFP-producing gastric cancers have an aggressive behavior with a high metastatic potential to the liver. In addition, their clinicopathological features are quite different from the more common AFP-negative gastric cancer.

Keywords: Alpha-fetoproteins; Liver metastasis; Prognosis; Stomach neoplasms.

Fig. 1

Patients selection.

Fig. 2

Relationship between preoperative serum AFP level and N stage. There was a signifi cant increase of median serum AFP level according to each N stage (2.3 vs. 2.4 vs. 2.7 vs. 3.4, P=0.001). AFP = alpha-fetoprotein.

Fig. 3

Relationship between preoperative serum AFP level and liver metastasis. There was a signifi cant increase of median AFP level in liver metastasis positive group compared to liver metastasis negative group (6.5 vs. 2.3, P=0.000). AFP = alpha-fetoprotein.

Fig. 4

Overall survival curves of gastric cancer patients with liver metastasis according to AFP-positivity (5-year survival rate 20% vs. 0%, median survival time 26.4 months vs. 11.4 months). AFP = alpha-fetoprotein.