Purpose: To determine serum levels of the soluble form of CD30 molecule (sCD30) in patients with Ki-1/CD30+ anaplastic large-cell lymphoma (ALCL), and to evaluate its correlation with clinical features at presentation and its possible role as a tumor marker to monitor response to treatment and subsequent follow-up.
Patients and methods: sCD30 serum levels were measured with an improved commercial sandwich enzyme-linked immunosorbent assay (ELISA) test kit in 24 patients with CD30+ ALCL at diagnosis and in 13 after treatment.
Results: Increased values (> 20 U/mL) at diagnosis were observed in 23 of 24 cases (median, 842.5 U/mL; range, 16 to 37,250) as compared with controls (P < .0001). These values were greater than those of 60 stage-matched cases of Hodgkin's disease (HD) (P < .0001). The highest median value was observed in patients with T-cell-type ALCL (1,690 U/mL), with a significant overall difference as compared with B- and null-cell types (P = .004). Phenotype maintained its significance when results were corrected for other parameters, such as age, sex, and stage (P = .03). sCD30 values returned to the normal range in complete remission (CR), but remained increased in one patient who only partially responded to treatment. Subsequent increases of sCD30 levels were recorded in four of four patients after relapse.
Conclusion: sCD30 appears to be a new biologic serum tumor marker of possible use in the clinical setting of CD30+ ALCL.