Serum immunoreactive and bioactive lactogenic hormones in advanced breast cancer patients treated with bromocriptine and octreotide.
6 patients with advanced breast cancer who had failed first and second line endocrine therapies received bromocriptine (1.25-2.5 mg twice daily per os) and octreotide (Sandostatin) via a continuous subcutaneous infusion (200-400 micrograms/24 h) until disease progression. Pre-treatment 24-h profiles of serum lactogenic hormones and their response to standard provocative tests were established and repeated at 2 weeks, and 3 and 6 months (or at tumour progression). Immunoreactive prolactin (ir-PRL), growth hormone (ir-GH) and insulin-like growth factor I (IGF-I) were measured by radioimmunoassay and bioactive lactogenic hormone levels (BLH) were estimated using the Nb2 rat lymphoma cell bioassay. Before treatment all patients showed episodic secretion of ir-PRL, ir-GH and BLH and provocative stimuli resulted in a peak of ir-GH and BLH maximal between 60 and 90 min after injection but no change in ir-PRL. After 2 weeks of treatment, ir-PRL levels were reduced to below the limit of detection in all 6 patients. Peaks of ir-GH and BLH were still apparent, although much reduced. Immunoreactive PRL continued to be profoundly suppressed in 3 of the 4 patients who remained on treatment for 3 to 6 months. Small pulses of ir-GH were still detectable in these patients with which BLH was, again, well correlated. After 2 weeks of treatment, serum IGF-I levels were reduced by 9-54% of the pretreatment values and generally remained suppressed throughout treatment. Clinically, 4 patients did not show disease progression for periods of up to 6 months and side-effects were minimal.
Anderson
E
E
Department of Clinical Research, Christie Hospital NHS Trust, Manchester, U.K.
Ferguson
J E
JE
Morten
H
H
Shalet
S M
SM
Robinson
E L
EL
Howell
A
A
D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000097:blood* / Q000188:drug therapy / Q000473:pathology; D001971:Bromocriptine / Q000008:administration & dosage; D005260:Female; D013006:Growth Hormone / Q000097:blood*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D008875:Middle Aged; D015282:Octreotide / Q000008:administration & dosage; D011388:Prolactin / Q000097:blood*; D013997:Time Factors
D001971:Bromocriptine; D007334:Insulin-Like Growth Factor I; D011388:Prolactin; D013006:Growth Hormone; D015282:Octreotide