Francesco Perrone, Maria Carmela Piccirillo, Francesca Di Rella, Ermelinda De Maio, G. Landi, Emanuela Rossi, Gerardo Botti, Ciro Gallo, V. Labonia, Andrea de Matteis, Giuseppe D'Aiuto, Francesco Nuzzo, Massimiliano D’Aiuto, Massimo Rinaldo, Adriano Gravina, Giuseppe Esposito, Alessandro Morabito, Carmen Pacilio, Rossi, E, Morabito, A, DE MAIO, E, DI RELLA, F, Esposito, G, Gravina, A, Labonia, V, Landi, G, Nuzzo, F, Pacilio, C, Piccirillo, Mc, D'Aiuto, G, D'Aiuto, M, Rinaldo, M, Botti, G, Gallo, Ciro, Perrone, F, and DE MATTEIS, A.
Purpose To compare the endocrine effects of 6 months of adjuvant treatment with letrozole + triptorelin or tamoxifen + triptorelin in premenopausal patients with early breast cancer within an ongoing phase 3 trial (Hormonal Adjuvant Treatment Bone Effects study). Patients and Methods Prospectively collected hormonal data were available for 81 premenopausal women, of whom 30 were assigned to receive tamoxifen + triptorelin and 51 were assigned letrozole + triptorelin ± zoledronate. Serum 17-β-estradiol (E2), follicle-stimulating hormone (FSH), luteinizing hormone (LH), Δ4-androstenedione, testosterone, dehydroepiandrosterone-sulfate, progesterone, adrenocorticotropic hormone (ACTH), and cortisol were measured at baseline and after 6 months of treatment. For each hormone, 6-month values were compared between treatment groups by the Wilcoxon-Mann-Whitney exact test. Results Median age was 44 years for both groups of patients. Letrozole + triptorelin (± zoledronate) induced a stronger suppression of median E2 serum levels (P = .0008), LH levels (P = .0005), and cortisol serum levels (P < .0001) compared with tamoxifen + triptorelin. Median FSH serum levels were suppressed in both groups, but such suppression was lower among patients receiving letrozole, who showed significantly higher median FSH serum levels (P < .0001). No significant differences were observed for testosterone, progesterone, ACTH, androstenedione, and dehydroepiandrosterone between the two groups of patients. Conclusion Letrozole in combination with triptorelin induces a more intense estrogen suppression than tamoxifen + triptorelin in premenopausal patients with early breast cancer.