The serum levels of NCC-ST-439, a monoclonal antibody raised against a huma
n gastric cancer xenograft (ST-439), were determined in 28 patients who had
undergone a curative resection of Dukes' C colorectal carcinoma. The preop
erative mean levels of NCC-ST-439 were 14.4 U/ml (range 1.0-280.0) and posi
tive (>7.0 U/ml for women under the age of 49, >4.5 U/ml for women over the
age of 50, and men at any age) in 6 patients. Recurrence of the disease af
ter a curative resection was encountered in 7 patients (serum NCC-ST-439 wa
s positive in 5 and negative in 2 patients). The positive serum NCC-ST-439
was associated,vith a significantly poorer disease-free survival time (P <
0.0001), In patients who had undergone a curative resection of Dukes' C col
orectal cancer, the sensitivity of NCC-ST-439 in the sera for recurrent dis
ease was 71.4% and specificity was 95.2%. The results of a preliminary stud
y suggested NCC-ST-439 to be a no, el marker for predicting recurrence afte
r a curative resection of Dukes' C colorectal carcinoma.