Serum neural cell adhesion molecule in multiple myeloma and other plasma cell disorders.

Serum embryonic neural cell adhesion molecule (eNCAM) levels were measured at diagnosis in 92 patients with plasma cell disorders. Significantly elevated levels of serum eNCAM were detected in patients with multiple myeloma when compared to both normal controls and patients with monoclonal gammopathy of uncertain significance (MGUS). Very high levels of serum eNCAM were seen in patients with high tumour burdens. There was a significant correlation between serum eNCAM and beta 2-microglobulin (beta 2m) (r = 0.33; P = 0.002), but not between serum eNCAM and C-reactive protein or serum albumen. There was a trend towards longer survival for patients with low serum NCAM. The median survival of the low serum eNCAM group (eNCAM < 20 U/ml) was 36 months compared to 16 months for the high serum eNCAM group (log rank test chi 2 = 2.42, P = 0.1). Serum eNCAM is a new marker of tumour mass in multiple myeloma and correlates with clinical stage and beta 2m. Patients with low serum eNCAM levels may have a survival advantage. Serum eNCAM warrants further evaluation as a tumour marker and prognostic factor in multiple myeloma.