Significance of early changes in the serum CA-125 antigen level on overall survival in advanced ovarian cancer.
OBJECTIVE
The relationship between survival and early changes in the serum level of the CA-125 antigen in patients with advanced ovarian cancer remains poorly defined.


METHODS
To explore this issue, the serum CA-125 values from 101 patients with advanced ovarian cancer who participated in a Southwest Oncology Group trial (SWOG 8412), which compared the systemic delivery of cisplatin/cyclophosphamide vs. carboplatin/cyclophosphamide (both delivered every 28 days for 6 cycles) in suboptimal residual stage III and IV ovarian cancer, were evaluated. All patients in this analysis had CA-125 values available for at least 8 weeks following initiation of chemotherapy. Cox proportional hazards regression was used in multivariate analysis to determine the prognostic significance of the CA-125 concentration.


RESULTS
While pretreatment CA-125 values did not correlate with survival, the concentration of this tumor marker 8 weeks after initiation of therapy was a powerful independent prognostic factor. The median survivals for patients (n = 51) with a CA-125 < 35 U/ml, vs. patients (n = 50) with a CA-125 > 35 U/ml, at this time point, were 26 months and 15 months, respectively (P = 0.0001). Further, women with serum CA-125 values <50% of their pretreatment concentration at 8 weeks experienced a median survival of 21 months, compared to only 10 months for individuals with tumor marker levels >50% of their baseline value (P = 0.0003).


CONCLUSIONS
Reduction in the serum CA-125 concentration over the initial two cycles of platinum-based chemotherapy is a powerful independent predictor of survival for patients with suboptimal stage III or IV ovarian cancer. Patients without significant declines in CA-125 after two cycles of platinum-based chemotherapy have a particularly poor prognosis.
Markman
Maurie
M
University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA. mmarkman@mdanderson.org
Federico
Massimo
M
Liu
P Y
PY
Hannigan
Edward
E
Alberts
David
D
D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D018394:CA-125 Antigen / Q000097:blood*; D016190:Carboplatin / Q000008:administration & dosage; D002945:Cisplatin / Q000008:administration & dosage; D017326:Clinical Trials, Phase III as Topic; D003520:Cyclophosphamide / Q000008:administration & dosage; D005260:Female; D006801:Humans; D008875:Middle Aged; D009367:Neoplasm Staging; D010051:Ovarian Neoplasms / Q000097:blood* / Q000188:drug therapy / Q000473:pathology; D011379:Prognosis; D016016:Proportional Hazards Models; D016032:Randomized Controlled Trials as Topic; D015996:Survival Rate
D018394:CA-125 Antigen; D003520:Cyclophosphamide; D016190:Carboplatin; D002945:Cisplatin