The aromatase inhibitor
letrozole in advanced breast cancer: effects on serum insulin-like growth factor (IGF)-I and
IGF-binding protein-3 levels.
Bajetta E, Ferrari L, Celio L, Mariani L, Miceli R, Di Leo A, Zilembo N, Buzzoni R, Spagnoli I, Martinetti A, Bichisao E, Seregni E.
Medical Oncology B Division, Istituto Nazionale per lo Studio e la Cura dei Tumori, Milan, Italy.
Serum insulin-like growth factor (IGF)-I and
IGF-binding protein-3 levels were measured in two groups of postmenopausal women with advanced breast cancer, who received the aromatase inhibitor
letrozole 0.5 or 2.5 mg p.o. once daily. Blood samples were obtained from 15 patients in each dose group at baseline, and one and three months after starting therapy. Circulating IGF-I and IGFBP-3 concentrations were determined by means of radioimmunoassay. In both dosage groups a statistically significant increase in the IGF-I levels was observed during three months of letrozole treatment (P=0.003). In addition, the multiple testing procedure yielded in the whole patient population a significant result in the comparison between mean IGF-I values after three months of therapy and those observed at baseline (P=0.004), the estimated average increase being of 24%. No significant result was obtained in the analysis for the dose effect (P=0.077) and for the time x dose interaction (P=0.208). Circulating IGFBP-3 levels did not appear to be affected by letrozole treatment in either of the dose groups. This is the first report concerning the short-term effects of letrozole on components of the IGF system in breast cancer patients; further investigations are warranted in order to confirm these preliminary data.
Pediatrics. 1993 Apr;91(4):716-20. Related Articles, Links
Long-term results of treatment with low-dose fluoxymesterone in constitutional delay of growth and puberty and in genetic short stature.
Strickland AL.
Spartanburg Regional Medical Center, SC.
This prospective study was designed to assess growth response, side effects, other possible long-term effects, and final adult height in boys treated with the oral androgen, fluoxymesterone. From 1973 to 1984, eighty-two short boys (71 with constitutional delay of growth and puberty [CDGP] and 11 with genetic short stature [GSS]) were treated with daily oral doses of 2.5 mg of fluoxymesterone from 6 to 60 months. Final height assessment was made from 1989 to 1991. A group of 34 untreated boys (26 with CDGP and 8 with GSS) were also followed to assess the accuracy of the Greulich-Pyle and Bayley-Pinneau (GP-BP) and sexual maturity index height prediction methods. During treatment, each patient had a 1.7- to 2.5-fold increase in linear growth velocity. Accelerated velocity (over baseline) continued as long as the bone age was less than 14 years. No adverse androgenic effects (or undue acceleration of puberty) were observed. Final height exceeded pretreatment predictions for CDGP + GSS by 6.1 +/- 3.5 (SD) cm (GP-BP) and 5.4 +/- 3.2 cm (sexual maturity index). It is concluded that a daily oral dose of 2.5 mg of fluoxymesterone can be used to accelerate linear growth in boys with CDGP and GSS when needed to alleviate emotional problems secondary to slow growth and short stature without fear of compromising final adult height.
PMID: 8464656 [PubMed - indexed for MEDLINE]
IMHO they picked this steroid because it does not raise estrogen you did mention at higher dose & like I said I read something on that, but think it is false and a repeated to often as fact.
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