OVX1 radioimmunoassay complements CA-125 for predicting the presence of residual ovarian carcinoma at second-look surgical surveillance procedures.

Abstract

PURPOSE:

At second-look surgical surveillance procedures, normal CA-125 levels can be associated with persistent disease in 50% to 60% of patients. A novel radioimmunoassay (RIA) has been evaluated for the ability to identify patients with persistent disease who have normal levels of CA-125.

MATERIALS AND METHODS:

The OVX1 double-determinant assay used a murine monoclonal antibody to detect an epitope on a high-molecular weight mucin-like glycoprotein.

RESULTS:

Apparently healthy individuals had serum OVX1 levels of 2.23 +/- 2.48 U/mL (mean +/- SD). Elevated serum OVX1 levels (> 7.2 U/mL) were found in 5% of 184 normal individuals and in 70% of 93 epithelial ovarian cancer patients with clinically evident disease. Among sera from these ovarian cancer patients, OVX1 was elevated in 68% of 76 samples with CA-125 levels more than 35 U/mL and in 76% of 17 samples with CA-125 levels less than 35 U/mL. In serum samples obtained at the time of positive second-look laparotomy, 59% of 41 patients with CA-125 levels less than 35 U/mL had elevated OVX1 antigen levels, whereas 41% of 22 patients with CA-125 levels more than 35 U/mL had elevated serum OVX1 levels. In patients with negative second-look laparotomies, false-positive results were eliminated by increasing the threshold of OVX1 to 10.5 U/mL. At this level, 32% of 41 patients with positive second-look operations had an elevated OVX1 level, despite a normal CA-125 level. When used in combination, CA-125 (> 35 U/mL) and OVX1 (> 10.5 U/mL) detected persistent disease in 56% of 63 patients with positive surveillance procedures, compared with 35% when CA-125 was used alone (P < .05).

CONCLUSION:

An elevated OVX1 level can alert oncologists to the possibility that ovarian cancer has persisted, despite the return of CA-125 to a normal range.

• Authors: F J Xu, Y H Yu, L Daly, K DeSombre, L Anselmino, G M Hass, A Berchuck, J T Soper, D L Clarke-Pearson, C Boyer
• Journal: Journal of clinical oncology : official journal of the American Society of Clinical Oncology (J Clin Oncol) Vol. 11 Issue 8 Pg. 1506-10 (Aug 1993) ISSN: 0732-183X [Print] United States
• PMID: 8336189 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antibodies, Monoclonal
• Antigens, Neoplasm
• Antigens, Tumor-Associated, Carbohydrate
• Biomarkers, Tumor
• Glycoproteins
• OVX1 antigen
• Proteins

Topics

• Animals
• Antibodies, Monoclonal
• Antigens, Neoplasm (blood)
• Antigens, Tumor-Associated, Carbohydrate (blood)
• Biomarkers, Tumor (blood)
• Female
• Glycoproteins
• Humans
• Mice
• Neoplasms (immunology)
• Ovarian Diseases (immunology)
• Ovarian Neoplasms (immunology, surgery)
• Predictive Value of Tests
• Proteins
• Radioimmunoassay
• Reference Values
• Regression Analysis
• Reoperation