Serum CA 125 is of clinical value in the staging and follow-up of patients with non-Hodgkin's lymphoma: correlation with tumor parameters and disease activity.

BACKGROUND

CA 125 is a glycoprotein produced by epithelial ovarian tumors and by mesothelial cells; its levels also have been shown to be elevated in patients with non-Hodgkin's lymphoma (NHL).

METHODS

The authors evaluated serum CA 125 levels in patients with NHL to elucidate the frequency of this finding, its relationship with other presenting features, and its potential role as tumor marker. One hundred and fifty-seven patients underwent the first CA 125 assessment at onset, 54 at disease recurrence or progression, and 62 during complete remission (CR).

RESULTS

Of the 157 patients evaluated at diagnosis (median CA 125: 26 U/mL; range, 2-1400 U/mL), 63 (40%) had increased CA 125 values. Higher CA 125 levels were associated with advanced disease, aggressive histology, mediastinal and/or abdominal involvement, bulky tumor, high tumor burden, effusions, contiguous extranodal extension, high serum lactate dehydrogenase (LDH) activity, and elevated beta2-microglobulin (beta2-M) levels. Parameters identified by multivariate analysis to be independently associated with high CA 125 were: aggressive histology, mediastinal and/or abdominal disease, bulky tumor, high serum LDH activity and beta2-M serum levels, and the presence of effusion (P = 0.0000; explained variation = 0.64). Of the patients presenting with abnormal CA 125 levels, all those who achieved a CR (35) and 3 of the 6 who achieved a partial response had normalization of CA 125 values by the end of treatment. Conversely, CA 125 remained above normal values in 18 nonresponders. All 62 patients evaluated during CR showed normal CA 125 levels. Among patients first evaluated at disease recurrence or progression, 22 of 54 (41%) showed increased CA 125 levels, which were associated with the same parameters of disease found in patients examined at diagnosis.

CONCLUSIONS

High serum CA 125 levels were found to correlate with mediastinal and/or abdominal involvement, high tumor mass, and effusions, reflecting the reaction of mesothelial cells to the tumor. Serum CA 125 is a reliable biologic marker for the staging and restaging of patients with lymphoma. Serial measurements are useful, in conjunction with other markers, for monitoring response to treatment.