Tumor-associated antigen TA90 immune complex assay predicts recurrence and survival after surgical treatment of stage I-III melanoma.
OBJECTIVE
Immune complexes (IC) containing the tumor-associated antigen TA90 can be identified in the sera of melanoma patients. We have shown that an enzyme-linked immunosorbent assay for TA90-IC can detect subclinical metastasis before surgical treatment of early-stage melanoma. We assayed the TA90-IC levels of postoperative sera from patients with melanoma and evaluated their relationship to recurrence and survival.


METHODS
Multiple archival serum samples prospectively collected during postoperative surveillance of 166 patients with American Joint Committee on Cancer stage I, II, or III melanoma were analyzed for TA90-IC in a blinded fashion. Results were correlated with disease recurrence and survival determined by database and chart review.


RESULTS
TA90-IC status in the early postoperative period was strongly correlated with survival. Five-year overall survival rates were 84% for TA90-IC-negative patients and 36% for TA90-IC-positive patients (P =.0001). Respective 5-year disease-free survival rates were 74% and 24% (P =.0001). The TA90-IC assay was a significant predictor of survival for both stage II and III patients. Multivariate analysis identified TA90-IC status as the strongest independent prognostic factor for both overall and disease-free survival. The TA90-IC assay was elevated in 54 (77%) of 78 patients who developed recurrent disease, becoming positive 19 +/- 7 months before clinical evidence of recurrence. Overall, the assay detected recurrence with a sensitivity of 78% and specificity of 77%. Exclusion of patients receiving postoperative immunotherapy with a polyvalent melanoma cell vaccine increased sensitivity and specificity to 92% and 86%, respectively.


CONCLUSIONS
The TA90-IC assay can accurately predict survival and detect the presence of subclinical disease after surgery for melanoma, which should be useful in selecting patients for adjuvant therapy. Because the TA90-IC assay detected recurrence on an average of 19 months sooner than did routine clinical and radiographic evaluation, it may allow more timely therapeutic interventions.
Kelley
M C
MC
Sonya Valley Ghidossi Vaccine Laboratory, John Wayne Cancer Institute, Saint John's Health Center, Santa Monica, CA 90404, USA.
Gupta
R K
RK
Hsueh
E C
EC
Yee
R
R
Stern
S
S
Morton
D L
DL
D000951:Antigens, Neoplasm / Q000032:analysis*; D005260:Female; D006801:Humans; D008297:Male; D008545:Melanoma / Q000175:diagnosis* / Q000401:mortality / Q000601:surgery; D009364:Neoplasm Recurrence, Local; D015996:Survival Rate
D000951:Antigens, Neoplasm; C113885:TA90 immune complex