CA72-4 antigen levels in serum and peritoneal washing in gastric cancer: correlation with morphological aspects of neoplasia

BACKGROUND: Determining levels of tumor markers in peritoneal washing enables likelihood of peritoneal recurrence to be ascertained in patients with high marker levels, thereby allowing provision of more accurate adjuvant treatment and postoperative follow up. AIM: To analyze the relationship between levels of tumor marker CA72-4 in serum and peritoneal washing, and morphological aspects of gastric carcinoma. METHOD: This study analyzed 32 consecutively-operated patients with gastric carcinoma, who underwent subtotal, total or palliative gastrectomy. The variables studied were CA72-4 levels in serum and peritoneal washing, lesion site, stage, degree of cell differentiation, operation performed, and number of extirpated and involvement lymph nodes. Of the 32 patient sample, 21 (65.6%) were male and 11 (34.4%) female. Mean age was 62.6 ± 14.2 years (29 to 91 years). Following anesthetic induction, peripherical venous blood was collected through percutaneous punction of an upper limb vein. After the procedure, 50 mL of physiologic solution at 37ºC was introduced into the cul-de-sac. A 10 mL volume of this liquid was aspirated from the cavity and the peritoneal washing tested for CA72-4 levels. Normal values for CA72-4 levels in serum were considered <7 U/mL and high levels as >7U/mL, whilst for the peritoneal washing normal levels were <0.61 U/mL, and abnormal >0.61 U/mL. RESULTS: Mean pre-operative serum levels for CA72-4 were 6.55 U/mL ± 15.30 (0.3 to 75.30 U/mL) whilst the mean level of CA72-4 in peritoneal washing was 8.50 U/mL ± 26.72 (0.3 to 142.00 U/mL); correlation between these levels was significant. Lymph nodes involvement by the gastric carcinoma correlated significantly with higher CA72-4 levels in both serum and peritoneal wash. There was no statistically significant correlation between serum level of CA72-4 and invasion into serosa by the gastric carcinoma. There was however, significant correlation between peritoneal washing levels of CA72-4 and involvement of serosa by gastric carcinoma. There was also a significant correlation between more advanced stages of gastric carcinoma and higher levels of CA72-4 in the peritoneal washing, although serum levels of CA72-4 and more advanced stage of gastric neoplasia showed no significant correlation. Degrees of cellular differentiation in the gastric carcinoma did not differ significantly with CA72-4 levels in serum or peritoneal washing. CONCLUSION: High levels of CA72-4 in peritoneal washing correlated significantly with lymph node metastasis and serosa involvement by the neoplasia, and also with more advanced stage of gastric carcinoma. The levels of CA72-4 in the blood correlated significantly with lymph node involvement by the gastric carcinoma, but not with serosa invasion or more advanced stage of neoplasia.