OFS in Premenopausal Node+ Breast Cancer With Low Genomic Risk

Endocrine Therapies With Ovarian Function Suppression in Premenopausal Node+ Early Breast Cancer With Low Genomic Risk (INTERSTELLAR Trial, KBCSG-25)

Among ER+HER2- premenopausal patients with N1 who undergoes primary breast surgery, we will identify the patients with a genomic low risk using the multigene-assay (OncoFREE®).

In these, ovarian function suppression with endocrine therapies including either tamoxifen or aromatase-inhibitors will be administered for 5 years.

• Among ER+HER2- premenopausal patients with N1 who undergoes primary breast surgery, we will identify the patients with a genomic low risk using the multigene-assay (OncoFREE®).
• In these, ovarian function suppression (OFS) with endocrine therapies including either tamoxifen or aromatase-inhibitors will be administered for 5 years.
• Either goserelin acetate or leuprorelin Acetate is allowed.
• These patients are able to choose bilateral salpingo-oophorectomy instead of OFS.
• Chemotherapy is omitted in these patients.

Inclusion Criteria:

• ER+HER2- breast cancer
• Premenopausal and age <=50
• T1 or T2
• N1 including micrometastasis
• Genomic Low Risk by OncoFREE test® (1-20)

Exclusion Criteria:

• Postmenopausal women
• ER-negative breast cancer