Endocrine therapies for patients with recurrent breast cancer: predictive factors for responses to first- and second-line endocrine therapies.
Breast cancer patients have been treated with four different hormonal agents, antiestrogen, progestin, luteinizing hormone-releasing hormone agonist and aromatase inhibitor, during the past 7 years in Japan. To investigate the efficacy of these agents for the treatment of recurrent breast cancer patients, we conducted a retrospective multi-institute survey in Japan. The clinico-pathological data of 131 patients, who received endocrine therapy as first-line treatment between 1993 and 1998, were collected from seven institutes. The median age of the patients was 55 (range 27-92) years, 75% of their primary tumors were estrogen receptor (ER)-positive or unknown, and 95% of the dominant metastatic sites were bone, soft tissue or lungs. The objective response rate to first-line endocrine therapy was 42.7%, and that to second-line therapy 42.5% (17 of 40 patients). Multiple regression analyses of predictive factors for a response to first- and second-line endocrine therapies indicated two independent factors, ER status of the primary tumors and dominant site of metastasis, for the former, and one independent factor, a response to first-line endocrine therapy, for the latter. Analysis of relationships between sequences of use of hormonal agents and objective response rates revealed that the choice of first-line hormonal agent did not influence the overall efficacy of first- and second-line endocrine therapies. Overall survival after first recurrence in patients with tumors exhibiting an objective response or stable disease to first-line endocrine therapy was significantly better than that in patients with tumors exhibiting progressive disease (p < 0.01). These findings suggest that an adequate selection of recurrent breast cancer patients referring the ER status, dominant site of metastasis and a prior response to endocrine therapy may contribute to better clinical outcomes of the patients.
Kurebayashi
J
J
Department of Breast and Thyroid Surgery, Kawasaki Medical School, Kurashiki, Okayama, Japan. kure@med.kawasaki-m.ac.jp
Sonoo
H
H
Inaji
H
H
Nishimura
R
R
Iino
Y
Y
Toi
M
M
Kobayashi
S
S
Saeki
T
T
D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000473:pathology; D018572:Disease-Free Survival; D020847:Estrogen Receptor Modulators / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D009364:Neoplasm Recurrence, Local; D011237:Predictive Value of Tests; D012044:Regression Analysis; D012307:Risk Factors; D016896:Treatment Outcome
D018931:Antineoplastic Agents, Hormonal; D020847:Estrogen Receptor Modulators