We evaluated the clinical usefulness of the
squamous cell carcinoma antigen (SCC) and CA 125,
serum markers of epithelial
cancer cells, in comparison with the serum concentration and tissue distribution of the aminoterminal propeptide of
type III procollagen (
PIIINP), a marker of connective tissue metabolism, in 31 patients with vulvar
carcinoma. The SCC concentration was increased in 42%, that of CA 125 in 14% and that of
PIIINP in 36% of the cases. The combination of SCC and
PIIINP increased the detection rate to 57% and that of all three to 64%. None of the
tumor markers correlated with the clinical stage of the disease. The initial values of the
serum markers did not discriminate between different patterns of the clinical behavior of the disease. Six patients were followed with serial determinations of the markers. In each case at least one of the markers correlated with the
clinical course of the disease. SCC did so in 5 cases,
PIIINP in 3 cases and CA 125 in 2 cases. The mean concentrations of SCC and CA 125, but not that of
PIIINP, were significantly lower during the periods of response to
therapy than during the nonresponsive periods. Immunohistochemistry of
PIIINP showed vulvar
carcinoma to be associated with a distinct collagenous stroma. In the junctional area of the stroma around the malignant epithelium, the
PIIINP positive fibers grew more sparse and irregular with decreasing differentiation of the
tumor. The present data suggest that SCC, CA 125 and
PIIINP are useful, especially SCC, in monitoring the clinical behaviour of the advanced
vulvar cancer, less so in predicting its prognosis.