Relationship between Ki-67 labeling index and survival in high-grade glioma patients treated after surgery with tamoxifen.
BACKGROUND
The Ki-67 is a nuclear antigen expressed in the G1, S, G2, and M phases of the cell cycle recognizable by the monoclonal antibody MIB-1. The Ki-67 labeling index (LI) is considered as a marker of proliferation (growth fraction rate), even if its use as prognostic indicator of cerebral high-grade gliomas is still debated. The aim of this study is to correlate the Ki-67 LI with survival in patients operated on for a malignant glioma and treated postoperatively with tamoxifen.


METHODS
Using the MIB-1 antibody, the Ki-67 antigen staining of surgical specimens was obtained in 26 patients operated on for a malignant cerebral glioma. After operation, 9 patients started to receive 40 mg/day, 8 patients 80 mg/day, and 9 patients 120 mg/day of tamoxifen. In 20 cases one or more cycles of i.v. carboplatin was administered. All patients received radiotherapy (4500-6000 cGy).


RESULTS
The overall mean survival rate was 19.8 months and the median 12 months; the 12-month and 24-month survival rates were 47% and 23%, respectively. The Ki-67 LI ranged from 2.3% to 62% (mean 24.1%, median 20.5%). Excluding 2 patients who died during the postoperative period, we analyzed the survival rates of the remaining 24 patients in relation to the value of Ki-67 LI. In relation to the index, patients have been divided into 3 groups, with different survival rates: L) Ki-67 LI < or =10%, with mean survival rate of 30.7 months, M) from 10.1% to 30%, with mean survival rate of 15.8 months, and H) >30%, with mean survival rate of 20.2 months.


CONCLUSIONS
Our preliminary observations seem to confirm the efficacy of TAM in modifying the survival of malignant gliomas and seem to indicate that tumors with a lower LI and those with a LI >30% could be associated, if treated with TAM, with a better survival than gliomas belonging to group M, who could have a higher tumor proliferation rate in comparison to group L and a lower response to protein-kinase-C antagonists than group H.
Mastronardi
L
L
Civilian Hospital, Department of Neurological Sciences, Terni, Italy. mastro@tin.it
Guiducci
A
A
Puzzilli
F
F
Ruggeri
A
A
D000328:Adult; D000368:Aged; D034961:Antigens, Nuclear; D001254:Astrocytoma / Q000188:drug therapy* / Q000503:physiopathology / Q000601:surgery; D001932:Brain Neoplasms / Q000188:drug therapy* / Q000503:physiopathology / Q000601:surgery; D005260:Female; D005909:Glioblastoma / Q000188:drug therapy* / Q000503:physiopathology / Q000601:surgery; D006801:Humans; D019394:Ki-67 Antigen / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009687:Nuclear Proteins / Q000378:metabolism; D011379:Prognosis; D015996:Survival Rate; D013629:Tamoxifen / Q000008:administration & dosage* / Q000009:adverse effects
D034961:Antigens, Nuclear; D019394:Ki-67 Antigen; D009687:Nuclear Proteins; D013629:Tamoxifen