CA-125 in ovarian cancer: relation between half-life, doubling time and survival.
In a retrospective study of 35 patients with stage III-IV ovarian cancer, the probability to reach a complete (CR) or partial remission (PR) was studied by comparing the initial level, half-life and normalisation time of CA-125 during chemotherapy. In 15 CR patients, pretreatment CA-125 level was lower (70 U/l, range 16-1500 U/l) than in 20 PR patients (800 U/l, range 60-9000 U/l). The median normalisation time (NT) was 6 weeks in CR (range 0.7-5.5 months) and 4 months in PR patients (range 1.2-9 months). Marker half-life was 12 days for the CR group (range 4.5-30 days) and 21 days for the PR group (range 5.5-39 days). Remission duration (r = 0.56) and log cell kill (r = 0.72) were correlated with survival. Combining initial tumour diameter, marker level and NT predicted CR in 87.5% and PR in 86%. Estimating log cell kill by combining marker half-life and doubling time gives more insight into tumour cell kinetics and individual survival.
Willemse
P H
PH
Department of Internal Medicine, University Hospital, Groningen, The Netherlands.
Aalders
J G
JG
de Bruyn
H W
HW
Mulder
N H
NH
Sleijfer
D T
DT
de Vries
E G
EG
D015295:Antigens, Tumor-Associated, Carbohydrate / Q000032:analysis*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D014408:Biomarkers, Tumor / Q000032:analysis*; D005260:Female; D006207:Half-Life; D006801:Humans; D010051:Ovarian Neoplasms / Q000188:drug therapy / Q000276:immunology* / Q000401:mortality; D011379:Prognosis; D012189:Retrospective Studies
D015295:Antigens, Tumor-Associated, Carbohydrate; D014408:Biomarkers, Tumor