Endocrine effects of adjuvant letrozole + triptorelin compared with tamoxifen + triptorelin in premenopausal patients with early breast cancer.
OBJECTIVE
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).


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-beta-estradiol (E2), follicle-stimulating hormone (FSH), luteinizing hormone (LH), Delta4-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.


CONCLUSIONS
Letrozole in combination with triptorelin induces a more intense estrogen suppression than tamoxifen + triptorelin in premenopausal patients with early breast cancer.
Rossi
Emanuela
E
Clinical Trials Unit, National Cancer Institute of Naples, Via Mariano Semmola, 80131, Napoli, Italy.
Morabito
Alessandro
A
De Maio
Ermelinda
E
Di Rella
Francesca
F
Esposito
Giuseppe
G
Gravina
Adriano
A
Labonia
Vincenzo
V
Landi
Gabriella
G
Nuzzo
Francesco
F
Pacilio
Carmen
C
Piccirillo
Maria Carmela
MC
D'Aiuto
Giuseppe
G
D'Aiuto
Massimiliano
M
Rinaldo
Massimo
M
Botti
Gerardo
G
Gallo
Ciro
C
Perrone
Francesco
F
de Matteis
Andrea
A
D000328:Adult; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy*; D017024:Chemotherapy, Adjuvant; D005260:Female; D042341:Gonadal Hormones / Q000097:blood*; D006801:Humans; D000077289:Letrozole; D008875:Middle Aged; D009570:Nitriles / Q000008:administration & dosage; D017697:Premenopause; D011446:Prospective Studies; D018709:Statistics, Nonparametric; D013629:Tamoxifen / Q000008:administration & dosage; D016896:Treatment Outcome; D014230:Triazoles / Q000008:administration & dosage; D017329:Triptorelin Pamoate / Q000008:administration & dosage
D042341:Gonadal Hormones; D009570:Nitriles; D014230:Triazoles; D017329:Triptorelin Pamoate; D013629:Tamoxifen; D000077289:Letrozole