Gastric cancer: tumor markers as predictive factors for preoperative staging

CEA, CA 19-9, and CA 72-4 are tumor markers commonly used for gastric neoplasms. The clinical importance of the preoperative serum levels of these tumor markers in gastric cancer (GC) is not well known. Even less is known about the predictive value of the preoperative serum levels of the β-subunit of human chorionic gonadotropin (hCGβ).

We designed a prospective study to evaluate the significance of the preoperative values of these tumor markers in GC. The serum levels that we considered as positive are as follows: CA 72-4, >4 U/ml; CEA, >5 ng/ml; CA 19-9, >37 U/ml; hCGβ-free subunit, <5 mUI/ml. These levels were correlated by pathological stage, lymph node status, and histology.

We studied 66 (42 male and 24 female) patients prospectively. Twenty-seven patients had stage I and stage II GCs, while 39 patients had stage III and stage IV GCs. Two patients tested positive for hCGβ. The preoperative positivity rates of CA 72-4 in patients at the early stages (stages I and II) and in patients with advanced disease (stages III and IV) were 0 and 28 patients, respectively. The preoperative positivity rates of CEA/CA 19.9 were 0/5 and 7/12 patients in early stages and advanced disease, respectively. The serum levels of these markers were not correlated with the histological type or tumoral grade of GC.

The preoperative serum level of CA 72-4 has the best predictive value in indicating advanced disease in patients diagnosed with GC. A combination of these four markers is better in predicting this situation.