Phase II parallel group study showing comparable efficacy between premenopausal metastatic breast cancer patients treated with letrozole plus goserelin and postmenopausal patients treated with letrozole alone as first-line hormone therapy.
OBJECTIVE
Goserelin and letrozole in premenopausal patients can result in clinical outcomes comparable to those obtained by letrozole alone in postmenopausal patients with metastatic breast cancer (MBC).


METHODS
A total of 73 patients with hormone-responsive MBC were included. Of those, 35 premenopausal patients received goserelin (3.6 mg subcutaneously every 28 days) plus letrozole (2.5 mg orally daily), and 38 postmenopausal patients received letrozole alone as their first-line endocrine therapy in a metastatic setting.


RESULTS
Baseline characteristics were similar in the two groups, except for a younger age (median, 41 v 53.5 years; P < .001) and a shorter disease-free interval (median, 1.8 v 3.3 years; P = .03) in the premenopausal group. Clinical benefit rates were comparable between the two groups (77% v 74%; P = .77). With the median follow-up of 27.4 months, there was no statistical difference in the median time to progression between the two groups (9.5 months [95% CI, 6.4 to 12.1 months] v 8.9 months [95% CI, 6.4 to 13.3 months]). In patients who did not receive bisphosphonate, letrozole +/- goserelin caused a greater loss of bone mineral density at 6 months compared with that of patients receiving bisphosphonate treatment (premenopausal group, -16.7% v 53.9%; P = .002 and postmenopausal group, -13.3% v 17.4%; P = .04 at the lumbar spine).


CONCLUSIONS
Clinical efficacies in premenopausal MBC patients with combined letrozole and goserelin therapy were comparable to those in postmenopausal patients treated with letrozole alone. Although letrozole +/- goserelin resulted in a modest increase in bone resorption, concurrent treatment with bisphosphonate could prevent bone loss at 6 months.
Park
In Hae
IH
Center for Breast Cancer, National Cancer Center, 323 Ilsan-ro, Gyeonggi-do, Korea.
Ro
Jungsil
J
Lee
Keun Seok
KS
Kim
Eun-A
EA
Kwon
Youngmee
Y
Nam
Byoung-Ho
BH
Jung
So-Youn
SY
Lee
Seeyoun
S
Kim
Seok Won
SW
Kang
Han Sung
HS
D000284:Administration, Oral; D000328:Adult; D000368:Aged; D018931:Antineoplastic Agents, Hormonal / Q000008:administration & dosage* / Q000009:adverse effects; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage* / Q000009:adverse effects; D001707:Biopsy, Needle; D015519:Bone Density / Q000187:drug effects; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000401:mortality* / Q000473:pathology; D018450:Disease Progression; D018572:Disease-Free Survival; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005260:Female; D017273:Goserelin / Q000008:administration & dosage* / Q000009:adverse effects; D006801:Humans; D007150:Immunohistochemistry; D007279:Injections, Subcutaneous; D053208:Kaplan-Meier Estimate; D000077289:Letrozole; D020714:Maximum Tolerated Dose; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000473:pathology*; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D009570:Nitriles / Q000008:administration & dosage* / Q000009:adverse effects; D017698:Postmenopause / Q000187:drug effects / Q000502:physiology; D017697:Premenopause / Q000187:drug effects / Q000502:physiology; D011336:Probability; D011379:Prognosis; D016016:Proportional Hazards Models; D018570:Risk Assessment; D018709:Statistics, Nonparametric; D016019:Survival Analysis; D016896:Treatment Outcome; D014230:Triazoles / Q000008:administration & dosage* / Q000009:adverse effects
D018931:Antineoplastic Agents, Hormonal; D009570:Nitriles; D014230:Triazoles; D017273:Goserelin; D000077289:Letrozole