Oral high-dose progestins as treatment for advanced breast cancer.
Fifty-two postmenopausal, previously treated advanced breast cancer patients who received oral high-dose progestins (medroxyprogesterone acetate [MPA] and/or megestrol acetate [MA]) were retrospectively reviewed. MPA was given to 45 patients and MA to 17 (10 earlier treated with MPA); 48 were evaluable for clinical response to progestin treatment, 43 for MPA and 5 for MA. Two complete responses and 10 partial responses (25%) with median duration of 9.5 months were seen. Forty percent of the patients obtained stable disease greater than or equal to 6 months with a median duration of 8.0 months. In patients with estradiol receptor positive (n = 31) and estradiol and progesterone receptor positive (n = 19) tumors the response rates were 35% and 37% respectively. No differences in serum levels of MPA or MA were observed in the different responding groups. The serum levels of MA were twice as high as MPA in spite of a dose of 160 mg/day of MA compared to 1,000 mg/day of MPA. A long disease-free interval, and positive receptor status of primary or metastatic lesions seemed to predict response to endocrine therapy even late in a therapeutic sequence. Side effects occurred in 11/45 (24%) of MPA treated patients and in 1/15 (7%) of MA treated patients. No difference in serum levels of MPA was found between patients with side effects and patients without side effects.
Lundgren
S
S
Department of Medical Oncology, University of Bergen, Norway.
Kvinnsland
S
S
Utaaker
E
E
D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000401:mortality; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D008525:Medroxyprogesterone / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000097:blood; D017258:Medroxyprogesterone Acetate; D008535:Megestrol / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000097:blood; D019290:Megestrol Acetate; D008875:Middle Aged; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D012074:Remission Induction; D012189:Retrospective Studies
D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; D017258:Medroxyprogesterone Acetate; D008535:Megestrol; D008525:Medroxyprogesterone; D019290:Megestrol Acetate