Predictive and prognostic value of serum AFP level and its dynamic changes in advanced gastric cancer patients with elevated serum AFP

Abstract

Aim: To investigate predictive and prognostic value of serum alpha-fetoprotein (AFP) level and its dynamic changes in patients with advanced gastric cancer with elevated serum AFP (AFPAGC).

Methods: One hundred and five patients with AFPAGC were enrolled in the study, and all of them underwent at least one cycle of systemic chemotherapy at our institute and had serum AFP ≥ 20 ng/mL at diagnosis or recurrence. Clinicopathologic features, serum AFP level at diagnosis and changes during treatment, first-line chemotherapy regimens, efficacy and toxicity, and survival information were collected. A Person's χ² or Fisher's exact test was used to measure the differences between variables. Survival prognostic factors were investigated using the Kaplan-Meier method and Cox regression.

Results: Median serum AFP level was 161.7 ng/mL (range, 22.9-2557110 ng/mL). Objective response rates (ORR) was significantly lower in the AFP ≥ 160 ng/mL group than in the AFP < 160 ng/mL group (30.4% vs 68.3%, P < 0.001). ORR to doublet regimens was significantly lower in the AFP ≥ 160 ng/mL group, whereas ORR to triplet regimens was similar between the two groups. Liver metastasis rate was significantly higher in the AFP ≥ 160 ng/mL group than in the AFP < 160 ng/mL (69.8% vs 50.0%, P < 0.001). Overall survival (OS) in the two cohorts did not show any significant difference (P = 0.712). Dynamic changes of AFP were consistent with response to chemotherapy, and median OS of patients with a serum AFP decline ≥ 50% and those with a serum AFP decline < 50% was 17.5 m and 10.0 m, respectively (P = 0.003). Hepatic (P = 0.005), peritoneal (P < 0.001), non-regional lymph node metastasis (P < 0.001), and portal vein tumor thrombus (PVTT) (P = 0.042) were identified as independent prognostic factors for AFPAGC.

Conclusion: Real-time examination of AFP has great predictive and prognostic value for managing AFPAGC. For those with markedly elevated AFP, triplet regimens may be a better choice.

Keywords: AFP-producing gastric cancer; Alpha-fetoprotein; Predictive factor; Prognostic factor; Triplet regimen.

Figure 1

The receiver operating characteristic curve analysis for predictive value of serum alpha-fetoprotein level. The area under the curve is 0.670.

Figure 2

Changes of serum alpha-fetoprotein levels at the time of diagnosis, evaluation, and progression. A: Dynamic changes of serum AFP in patients whose AFP declined by ≥ 50% when evaluated as PR; B: Dynamic changes of serum AFP in patients whose AFP declined by < 50% when evaluated as PR. PR: Partial response; PD: Progressive disease.

Figure 3

The median overall survival of patients with liver metastasis and those without was 16.7 m and 12.0 m, respectively (P = 0.048).

Figure 4

The median overall survival of patients with a ≥ 50% serum alpha-fetoprotein level decline and those with a < 50% decline was 17.5 mo and 10.0 mo, respectively (P = 0.003).